In our family we have variations on "the endless summer". Last year the kids dubbed it the endless summer of fun (ESOF 2012) and this year they have the endless summer of horses (ESOH 2013). The two daughters are spending the summer together in Berkeley. Older is in grad school and spending a lot of time training horses. Younger is visiting older down from college and running a summer horse camp for horse-crazy girls at the same barn. Yup, what were we thinking when put them as toddlers on top of the slow ponies in the roundabout at Griffith Park? Seems to have worked out well: they've got horses and they've got each other.
My summer is the endless summer of sports (ESOS 2013) now that my wonky valve is long fixed. I can't imagine what it would be like if I hadn't done that. Likely huffing and puffing just walking to the car. Glad I sidestepped that badness.
Lately it's been a lot of ultimate frisbee - played on a football field - about 6 to 8 hours a week. And hiking too. For my OHS/MV-repair anniversary I do what I call my "walkabout", which is a long weekend of mountain solo dayhiking in the Sierras. This year I put in 50 miles in 3 days. Then went back out a couple of weeks later for a 29 mile overnight mountain backpack to see if I could do it. Crazy thing, even though I was lugging a pack (to be fair, was going ultralight) I polished it off in one day. Gotta love the results now 26 months post-surgery.
My honey's summer isn't ESOS 2013 since she's still recovering from a broken leg she picked up while adventure skiing last winter. And I mean adventure. We splinted up and self-rescued out of the back country at dusk and drove down the mountain to the ER. Luckily it was a non-displacement fracture. But still it is taking a while. We're now going on 3 mile hikes together pretty routinely, and hope to get back to a higher cadence and longer distances in the fall. We've done several long weekends of car-camping / day-hiking and visiting the kids up in Berkeley. She's off on travel at the moment, with 4 more weeks of trips planned - so I think her summer is more like ESOT 2013 (endless summer of travel). I'll be joining her for parts of those trips, so maybe I'm having a combined sports/travel endless summer.
One thing it has not been is the endless summer of blogging (ESOB 2013 - not). So all that water under the bridge has left me with a short pile of topics I'd like to write about over the next while. Aortic valve repair is becoming more and more prevalent for aortic insufficiency and has excellent outcomes, similar to the excellent results for mitral valve repair. That seems like a good topic to tackle. There is exciting work in tissue engineering, which aims to surgically implant new valves grown using a patient's own stem cells. I still haven't done the "what's on my bookshelf?" journal entry. And there are some interesting developments in rheumatic fever prevention in developing nations which promises to dramatically reduce the global burden of valve disease. This reduction has already taken place in developed countries and is part of the ongoing global revolution in overall health that has lifespans improving in almost every country (except those whose leaders are so despotic they actively prevent people from improving their lives) . Finally, I recently came across some research that hints at connections between diet, our gut microbiomes and heart disease that may lead to therapies reducing our risks of clogged arteries and resulting badness.
Well, with that I'll return you to your own endless summers.
Deb Ziegler asked me on my guestbook page about where researchers get their information about morbidity and complications following heart valve surgery.
Let me first say that there are privacy rules<sup>1</sup> that generally prevent associating patients with data without consent. So the statistics are usually just that: statistics, rather than full records.
Next, there are 2 basic kinds of data sets: retrospective and prospective.
Retrospective studies use medical records that are generated as a matter of course by physicians regarding their patients. They cull the relevant data and assemble it into tables etc. The medical records are a hodge-podge of formats, notes, images, and so on and expensive to work with. Often studies using them will be of patients at a single hospital where there is some uniformity of format, but then the sample size is relatively small.
The Society of Thoracic Surgeons maintains a database for cardiac surgery<sup>2</sup>. From their website: "The Adult Cardiac Surgery Database, now containing more than 4.5 million surgical records, represents an estimated 94 percent of all adult cardiac surgery centers across the U.S." This represents a large set of statistics. It is hard to use though, requiring a proposal, evaluation/screening, and queries performed by the database administrators. Its large size and uniformity make it a potential gold mine for generating "evidence-based" knowledge. Surgeons submit data to the database, but once patients pass out of the reporting surgeon's care I'd assume it becomes rather incomplete.
Another example of a retrospective database, but grim, is the Social Security Deaths Database<sup>3</sup>. It lists the names and social security numbers of people whose deaths have been reported to the Social Security Administration. It is often used to assess survivorship in retrospective studies when patients have been lost track of in the medical records themselves. You do not want to be in this database!
Then finally, there are "case studies" which dive into a particular patient's details. Case studies are a popular feature in the medical journals.
Prospective studies are designed before the fact and patients are "enrolled". Consent is often obtained (required in fact under many circumstances). The data formats are rigorous and uniform. A famous example is the Framingham Heart Study<sup>4</sup>, which first showed the high heart disease risk of cigarette smoking. In prospective studies patients typically receive special exams, undergo interviews, and, in clinical trials, receive a variety of treatments to test their effects. Clinical trial studies are subject to rigorous oversight to ensure the Hippocratic oath - "do no harm" - is being upheld.
In general, retrospective studies cover more patients (millions in some cases), are less specific, less costly, and result in associations between risk factors and health effects.
Prospective studies cover fewer patients, are more specific, more costly, and can result in direct cause and effect relationships.
Authors of each paper in a medical journal describe in detail where they got their data from. Part of understanding the results is understanding the source of the data. Obviously data quantity and quality are important issues. There is a whole field of biostatistics whose subject is the degree to which reliable conclusions can be drawn from medical data.
We are all unique and our health trajectories are especially so. Our own medical data is highly valuable to each of us personally as it guides our own treatments. But it can also be used to guide the treatments of others when combined into large datasets and properly understood. So think of your medical data as a gift to the world to make life better all around.
Wow Deb, I wasn't expecting to turn this into a full-fledged journal post, but your question was interesting and needed more than a superficial answer.
1. In the USA, the <a href= "http://www.hhs.gov/ocr/privacy/">Health Information Privacy Protection Act</a> governs the collection and dissemination of patient medical information.
2. <a href="http://www.sts.org/national-database">Society of Thoracic Surgeons Database</a>
3. <a href="http://www.ntis.gov/products/ssa-dmf.aspx">Social Security Administration's Death Master File</a>
4. <a href="http://en.wikipedia.org/wiki/Framingham_Heart_Study">Framingham Heart Sudy Wikipedia artcle.</a>
If you've been diagnosed with severe mitral regurgitation, raise your hand. This post is for you.
When they do various tests on you and tell you the results you are probably thinking something like: lots of people before me had these same test results, what happened to them?
It's a darned hard question to answer, but you are in luck because there's been some work on exactly this question for mitral regurgitation patients. These studies are hugely useful for planning your future, so let's dive in to one<sup>1</sup> that has been influential.
First off, this was a prospective study, which means that the study participants were chosen before being poked, prodded, and results tallied. 456 patients were given echocardiograms and then their medical histories were followed for years. This is a powerful method for exploring correlations between diagnostic data and outcomes, in this case the correlations between various quantitative measures from their echo exams and their heart health.
You can measure a lot of things off an echo and some of these are more useful than others. A useful number is one that can be used to guide treatment for good outcomes. And according to this paper the most useful number<sup>2</sup> is the "effective regurgitant orifice" area (ERO), which is a measure of the size of the opening between your mitral leaflets that the wrong-way blood is going through. It makes sense that the bigger this opening the worse things are, and this is borne out by the statistics.
When the study participants are <i>stratified</i>, or grouped in ERO ranges, the picture that emerges is dramatic. Here I am linking to Kaplan-Meier aka survival curves<sup>3</sup> for the study participants in various ERO bins.
These curves are for overall survival, which means that those that dropped out did so for heart-related reasons as well as other causes of death. They show very clearly that larger ERO values are worse, and that those of us with ERO values larger than 40 square millimeters have only a slightly better than even chance of being around five years on.
A companion figure in the paper zeroes in on the rates of death in the study group from cardiac causes only (below)<sup>4</sup>.
If your ERO is less than 20 square millimeters, then you are running a 3% risk of death from cardiac causes over the next 5 years. 40 or over? 36% chance.
That doesn't sound so hot if your ERO is over 40, like mine was. But the good news is that surgical mitral valve repair prior to the onset of symptoms restores normal life span<sup>5</sup>.
So there's the value of your ERO measurement. It lets you know which of these cohorts you are in, and then looking at the survival curves what the historical experience of that cohort is.
The bottom line here is be sure your cardiologist gives you your ERO number since it contains high quality information needed to guide your course of treatment.
Keep the beat -- DVB
1. The paper is freely available: <a href="http://www.nejm.org/doi/pdf/10.1056/NEJMoa041451">Enriquez-Sarano, Avierinos, Messika-Zeitoun, Detaint, Capps, Nkomo, Scott, Schaff and Tajik, <i>Quantitative Determinants of the Outcome of Asymptomatic Mitral Regurgitation</i>, New England Journal of Medicine volume 352, page 875 (2005).</a>
2. The authors considered a large number of quantitative measures and determined which had the best utility in terms of predicting outcomes using statistical methods.
3. See my journal entry on July 3, 2012 titled "I was expecting more time with you my love".
4. If you carefully compare these two figures you will also note that the death rate from <i>non-cardiac</i> causes is significantly higher in the larger ERO groups, even though the average age was younger. This means that severe mitral regurgitation makes you more susceptible to other potentially fatal problems.
5. See my journal entry on July 15, 2012 titled, "What happens if I don't get my mitral valve fixed?"
While waiting waiting for permissions to include some graphics in the journal entry I'm crafting on echo numbers I wanted to give everyone a happy holidays greeting. It seems a particularly crazy end-of-year this year, what the with Mayan apocalypse, fiscal cliff, and sadly Sandy Hook. And then on top of it all we have our heart valve wonkiness to various degrees. Hug your kids, hug your folks.
The Mayan apocalypse passed uneventfully with the begin of its new cycle, which is just a page-turn of an obscure calendar. The fiscal cliff will turn out more or less OK for most folks as the system adapts to its latest round of craziness. Though lets be mindful of those who will be hurt by it. And Sandy Hook will hopefully spark the public health debate over guns that we've needed for a long time as we contemplate how precious each child is. And adult.
For all of us on the journal our valves continue to be a focus. As time goes on and our surgeries recede into the past, life for the most part gets back closer to normal. We can be thankful for the advances of modern medicine. Surgeries and treatments get better, more is researched and learned, and those who pay attention lead more heart-healthy lives. Each year's crop of valve patients faces an easier road than the year before's. Thats a good holiday gift.
What can we be looking forward to on behalf of future valve patients? Better minimally invasive methods to replace open heart access and reduce the fear factor. Further improvement and more widespread application of repair techniques for aortic valves. Better medical risk management. Tissue regeneration therapies. Eventually progress toward prevention. In the old days valve problems were a substantial killer. Now not so much in the first world, but still expensive and traumatic. One day, they will be only a distant memory. So as the old year gives way to the new, let's look forward to the good things to come.
Just in time for Thanksgiving I completed a new personal "Challenge". A capital-C Challenge like this is one where you set a goal, announce it out loud, it takes place over a specific time period, and has something to measure it by. Oh, and it's hard to do.
In this case it was a diet challenge. Not my usual gig, but my last couple of blood tests showed borderline high glucose at or just above 100 milligrams of glucose per deciliter of blood. OK, jargon, but anyone who tests their blood sugar knows what that is. Normal is 65-99, and a little bit high is a hint of insulin intolerance, which is a very common pre-diabetic condition. That didn't sound so good to me since diabetes is one of the top killers nationwide<sup>1</sup>.
Being a real believer in nipping things in the bud I took on the Challenge: for a month no added sugar, none in my coffee, none in my tea. No soda, no juice, no sweet pastries, no candy. No ice cream, no chocolate. Then at the end of the month check my blood glucose level to see how I did.
Having the Challenge end just before Thanksgiving turned out to be a good motivator for staying the course. Every time I was tempted to waver the thought came "Arg, then the Challenge will reset and go over Thanksgiving. That won't be fun. Arg."
Well, I stuck with it. When I went in to get my blood tested<sup>2</sup> the other day, what do you know. 89 mg/ml. Right in range for normal. That's a Challenge met and a good result. Now I know changing what I eat makes a difference and how big a difference it makes.
I'll probably be making some permanent changes to keep that glucose level down, but it looks like being a little less spartan will still be OK. That's nice because I still have one of the world's original sweet tooths.
Happy Thanksgiving -- DVB
1. One of the Center for Disease Control's latest publications, <a href="http://www.cdc.gov/nchs/data/nvsr/nvsr61/nvsr61_07.pdf">Deaths: Leading Causes for 2009</a>, lists diabetes as the 7th ranked cause of death in the US. Heart disease is 1st.
2. Turns out you can order your own blood test, I had mine done by LabCorp.
When I went for my initial consult at UCLA, a bunch of magic occurred. I wrote earlier about listening to my heart beat. Another piece of magic happened when I asked if there was anything to do pre-surgery that would help cut risks.
I'd already learned from my study of survival curves that the average mortality risk for patients diagnosed with severe mitral regurgitation is about 1/2% per month. Since I was facing a probable 1-2 month wait for surgery, this meant that I had roughly as much chance of dying before the surgery as during or after it.
So when my consulting cardiolgist said we might consider an afterload reducing drug, like those used by patients with high blood pressure, that sounded good to me. Afterload just has to do with the amount of work the heart has to do pumping blood to the rest of the body. It pumps against a pressure, and that is called the afterload. At the time the evidence that this was beneficial was rather thin, only a couple of papers, but the drugs are safe (used by millions to reduce blood pressure) so I got myself a prescription. Not much to lose, but to gain was cutting my overall mortality risk by up to half. Not a bad deal.
Then a year after my surgery there appears a study of studies that demonstrates what I'd call significant benefit for mitral valve regurgitation patients who take ACE inhibitors or angiotensin II receptor blockers (ARBs)<sup>1</sup>.
The problem is that mitral regurgitation is a progressive disease and doesn't get better by itself. As the valve becomes less and less effective, the left ventrical's ejection fraction decreases (the fraction of blood that gets pumped in the right direction). If this goes on too long, well, let's just say it is not good. As in fatal.
This study of studies found that the amount of regurgitation was reduced in patients who took the drugs. Patients who don't take drugs increase their regurgitant fraction (that's bad). So the drugs demonstrated a significant beneficial effect. In the studies that measured it, patients' left ventrical volumes were also reduced. That means the progressive enlargement that's part of valve disease was reversed.
These improvements don't mean that mitral regurgitation can be cured by the drugs - more likely they just gave some breathing room to these patients by reducing the amount of work their heart was doing pumping blood the wrong way. Enough breathing room to temporarily allow some reversal of damage to the heart. That reversal could translate directly to a reduction in mortality risk.
So what does this mean for you? Well, I'm not a medical doctor, but I can suggest putting this on your list of topics to discuss with your cardiologist if you are facing mitral valve repair: "Do you think I might benefit from an afterload reducing drug like an ACE inhibitor or ARB between now and surgery?".
And how about folks with aortic regurgitation? Here the literature is thin, but there are hints of benefits<sup>2</sup>. So you guys might want to put the same question on your discussion list. Hopefully more studies will come out soon to clarify the picture. Some of you may even already be on an afterload reducer for high blood pressure or other reasons.
Be your own advocate! -- DVB
1. <a href="http://www.icr-heart.com/journal/content/2012/may/abstracts/article.php?id=1289"><i>Pharmacotherapy in the Treatment of Mitral Regurgitation: A Systematic Review</i>, Craig E. Strauss, Sue Duval, Dan Pastorius, Kevin M. Harris, The Journal of Heart Valve Disease 2012;21:275-285.</a> This article, like many others is behind a paywall, but the abstract is available for free. Don't get me started on paywalls. I feel that to the extent taxpayer's dollars are used in research, the results should be freely available.
2. <a href="http://content.onlinejacc.org/article.aspx?articleid=1146944"><i>The Impact of Renin-Angiotensin-Aldosterone System Blockade on Heart Failure Outcomes and Mortality in Patients Identified to Have Aortic Regurgitation: A Large Population Cohort Study</i>, Douglas H.J. Elder et al, J Am Coll Cardiol. 2011;58(20):2084-2091.</a> However, an accompanying editorial notes that at least part of the effect seen may be because some patients may be benefiting from these drugs acting on high blood pressure and other non-valve diseases. That is a good thing too.
#1 <input type="checkbox"> Win an Olympic Gold Medal
#2 <input type="checkbox"> Have open heart surgery
Yeah, who picks #2?
No wonder a bunch of us who undergo heart surgery become depressed, not really a surprise. And if it were just "something to get through" that would be bad enough because of the unpleasantness. But depression is associated with increased mortality risk in heart patients, which is worse than unpleasant, so this is a big deal.
I'm writing this because new HVJer <a href="http://www.heart-valve-surgery.com/journals/user/dianababcock">Diana Babcock</a> asked if anyone had any ideas for dealing with cardiac depression and because the latest issue of Nature Cardiology Reviews arrived in my mailbox today. And right there, inside is a blurb reporting on the results of a clinical study looking at exercise (and drugs) to combat cardiac depression<sup>1</sup>.
Now mind you, this study is of patients with coronary artery disease, not valve disease. But wonky hearts are wonky hearts and let's just consider that what goes on in your head is similar.
Here's the scoop: depressed patients who complete a 16 week program consisting of thirty minute sessions of aerobic exercise three times a week feel just as good as those who take anti-depressants and a whole ton better than those who take a placebo pill.
So what does this mean to you if you're feeling blue after your valve surgery? It means there's a good chance you'll benefit from some structured exercise at this modest level. And the benefits could be as large as the benefits from taking anti-depressant medications (but hey, no nasty side-effects). Just check in with your doctor before hand if you don't already have unlimited clearance.
There was a bonus prize for those who were in the exercise arm of the clinical trial. They had better heart rhythm too, and that's associated with better long-term outcomes.
Yes! Two more reasons to get exercise. Good for your mind as well as good for your body.
Keep movin' -- DVB
1. <a href="http://content.onlinejacc.org/article.aspx?articleid=1305794">Blumenthal et al. <i>Exercise and pharmacological treatment of depressive symptoms inpatients with coronary heart disease</i>, Journal of the American College of Cardiologists, volume 60, page 1053 (September 18, 2012)</a>
I didn't know much about heart valves when I found out I needed mine fixed. I guess I'd heard you could get one replaced if things were bad. It didn't sound like fun, but better than the alternative. And that about sums it up.
I needed to know more, and fast. Crash course. Because this is a big deal, and its complicated, and my background is not really medicine. Yeah, I'd done some work a while back with building medical X-ray machines, imaging with them, and figuring out new algorithms to tease information from them. But that didn't give me any particular insight to heart valves.
So I did what I do when I need to learn fast: Google, Amazon, consult. I swear, Google boosts your IQ by 10 points. Getting the right stuff<sup>1</sup> from Amazon a similar amount. Consulting<sup2</sup> gels up what you know, fills in gaps, and gives you new pointers. I'm a firm believer in getting educated.
If you are reading this, you've already found Adam's site and know about his book. Explore the links here and what links from them. Google and use wikipedia to explore further using keywords. If you are technically minded Google Scholar will bring up the medical literature, much of which is free access. Be sure you locate "the Guidelines"<sup>3</sup> (see my June 30 post). Track down some books you'd like to read, maybe even get a hold of online excerpts. I'll post later on about what's on my bookshelf. Note down a list of questions and discussion topics for your consults and go through them systematically. It may help to take someone along to help keep on track or take notes for you<sup>4</sup>.
Smart people live longer, presumably because they make better health decisions<sup>5</sup>. It's smart to be smart. And happily you can smarten yourself up with time and resources.
<i>Get smart!</i> -- DVB
1. If your credit card is fat, you can just click away online - new or used. Other choices are to visit your state university's medical school library, use interlibrary loan at your local library, or borrow from your cardiologist.
2. Learn as much as you can <i>before</i> your big consultation. That way you can get the most out of the conversation.
3. The "Guidelines" are the collected wisdom of how to treat valve disease, published by the American Heart Association and American College of Cardiologists: <a href="http://tinyrul.com/7gw25lb">
The American Heart Association and American College of Cardiologists Guidelines for the Management of Patients with Valvular Heart Disease</a>.
4. Having someone there to keep the conversation on track can be very helpful. Do some conversation planning too so you know what track to keep it on. It will help avoid those "Doh! I forgot to ask!" moments.
5. This is amazingly difficult to rigorously test. What ethical experiments would you run? So it's one of those "correlation hints at causation" things.
You've got a plan for your surgery, right? How about recovery? That's something that's often missing: your recovery plan.
It's something that you should think about. A good plan well carried out is likely to get you on the road to healing and out of the hospital sooner, leave less opportunity for complications to arise, have you be stronger and more resilient if they do, and just all-around making you fell better.
So in this blog entry I want to motivate the idea of your recovery plan by giving evidence that its a good idea, and I'm going to focus on exercise as a key component. You see, exercise "exercises" primal<sup>1</sup> metabolic and healing pathways by generating chemical and mechanical signals that in turn reduce inflammation, promote tissue repair, boost the immune system, and improve your cells' oxygen utilization and energy production. While the detailed mechanisms for how this all works are still being actively and vigorously researched, what is evident is the beneficial results that are possible.
So, what is the evidence?
The first evidence is long-standing and flies in the face of common sense. Or maybe it's just that common sense has lost touch with our animal basics. Simply: getting out of bed and moving around at the earliest speeds recovery. This is called early ambulation in a 1938 journal article<sup>2</sup> which pretty much leads with this great anecdote:
"The value of the method was brought to Dr. Leithauser's attention by a young man on whom he had done and appendectomy in 1938. The patient insisted on going home on his first post-operative day. On the next day, he drove 30 miles into town to do some shopping. He passed the following days by working in his garden. When he strode into Dr. Leithausers's office after a 40-mile drive on his fifth post-operative day, Dr. Leithauser was impressed with the most apparent effect of early ambulation. This was the patient's rapid return of strength and free activity."
The paper goes on to describe a rigorous study demonstrating scientifically that there are definite and measurable benefits to patients.
So now, all of us heart surgery patients are rousted out of bed before 24 hours have passed to take some steps. I gotta say, those were the hardest steps I ever took. Shaking and hurting, I could hardly put one foot in front of the other. It took me 5 minutes to go 50 feet. Then I had to sit down and recuperate. And do it again. By the time another 24 hours was up I clocked a mile total. Two the day after, and three in the morning of the next before they sent me home. Hey, not much else to do in there.
Which brings me to the TV. If you think the TV sucks the life out of you at home (we chucked ours years ago), then think about what it does in the hospital. My hospital room had a TV, maybe a few hundred channels on it. Yours will too. Best advice, unplug it. Your job #1 is to recover fully, and as fast as you can. A British study<sup>4</sup> found that bypass and valve surgery patients who had no TV walked 2 to 3 times more during their hospital stays and were discharged on average one day earlier. That is a huge immediate benefit and could translate into a long term survival benefit as well. Not to mention the cost of a day's extra stay. Just right there you can do your part to keep medical costs down.
You can get volunteers to do almost anything in the name of medical science it seems. In order to study the effects of exercise on wound healing, volunteers were given intentional wounds on their arms and divided into two groups, one sedentary and one following an exercise program<sup>3</sup>. The folks who followed the exercise program, moderate exercise three times a week for an hour, healed <i>weeks</i> faster than those who did not. Wow! That is huge.
How does that work with valve patients? It's hard to tell because how do you non-invasively and inexpensively check how fast a heart is healing? Well, you can use exercise tolerance as a proxy. A French study<sup>5</sup> found that early exercise after mitral valve repair improved cardiovascular performance significantly. Patients who followed a 6-7 week program including calisthenics and stationary bicycle training improved their maximum oxygen uptake by 20%. A main result of this study was to show that a pretty decent exercise level (5 days a week for 60-80 minutes) is safe and had no ill effects in their sample of 251 patients.
There is a gap between walking the corridors in the days before being discharged and when most cardiac rehab plans will take you at about 4 weeks post-surgery. It may be smart to fill that gap with ongoing exercise that builds your strength and promotes healing. Reading the blogs, there are plenty of HVJ folks who are walking a a mile or two a day after being discharged. I'm sure it's not easy, but I'm equally sure it really helps.
One reason its not easy is because it hurts. Exercise improves pain tolerance<sup>6</sup>, so it will hurt less as you keep doing it. This is also a good reason, aside from the conditioning and immune system resiliency you get from it, to have an exercise program going in to surgery if you doctor advises. You will already have raised your pain tolerance threshold and that will benefit you from the moment you begin your recovery.
Now, I am not a medical doctor, so you will want to discuss exercise and your recovery plan with your cardiologist. I hope I've given you some discussion topics that will be helpful.
1. These biochemical pathways have evolved gradually over billions of years since life formed on earth. There are two key ideas in evolution. The first main idea is that offspring vary slightly from the parent, which is directly observable. There are a number of well-understood processes that change, add, mix, and delete DNA (the molecule that governs genetic heredity) accounting for these differences. The second main idea is that not all offspring themselves reproduce - also directly observable - so only those that do pass on their DNA to the following generation. The combination of these two obvious facts means variations resulting in DNA changes that reduce the chance of reproduction are lost and those that enhance reproductive success are amplified. Over time - billions of years - by keeping the good changes and losing the bad changes evolution proceeds to create DNA-encoded mechanisms that enhance reproductive success. Like those involved in healing.
2. E. Reise in 1899 first reported the benefits of early ambulation, as referenced in a very readable and prescient paper by James Blodgett in 1948 available <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1929770/pdf/bullnyacadmed00468-0049.pdf">here</a>. Blodgett even noticed the reduced infection rates of folks who got up and walked around soon after surgery.
3. S. Papaspyros, S. Uppal, S. A. Khan, S. Paul, D. J. O’Regan, <a href="http://ejcts.oxfordjournals.org/content/34/5/1022.full.pdf+html">Analysis of bedside entertainment services’ effect on post cardiac surgery physical activity: a prospective, randomised clinical trial</a>, European Journal of Cardio-thoracic Surgery 34, 1022 (2008).
4. Charles F. Emery,1,2,5,6 Janice K. Kiecolt-Glaser,1,3,5,6 Ronald Glaser,4,5,6 William B. Malarkey,2,4,5,6 and David J. Frid <a href="http://biomedgerontology.oxfordjournals.org/content/60/11/1432.full">Exercise Accelerates Wound Healing Among Healthy Older Adults: A Preliminary Investigation</a>, Journal of Gerontology: MEDICAL SCIENCES, 2005, Vol. 60A, No. 11, 1432–1436.
5. <a href="http://journal.publications.chestnet.org/article.aspx?articleid=1083766">Early Exercise Training After Mitral Valve Repair</a> Philippe Meurin, MD; Marie Christine Iliou, MD; Ahmed Ben Driss, MD, PhD; Bernard Pierre, MD; Sonia Corone, MD; Pascal Cristofini, MD; and Jean Yves Tabet, MD; Chest 2005;128;1638-1644.
6. <a href="http://www.springerlink.com/content/d481205hw3671313/">Does aerobic exercise improve pain perception and mood? A review of the evidence related to healthy and chronic pain subjects</a> Current Pain And Headache Reports, Volume 11, Number 2 (2007), 93-97.
What happens if my severe aortic stenosis is not treated?
Journal posted on July 21, 2012
Once symptoms develop, it's not good. Let me show you the evidence.
These are a couple of Kaplan-Meier curves from a study of severe aortic stenosis patients<sup>1</sup>. First take a look at the time axis and be alarmed. In previous charts the time was in years. Here it is in months. So get your game face on and focus, this is a new ballgame. The curves show that as long as a patient doesn't have symptoms, they experience a 5% per year risk (top line). Pretty high, about the same as untreated severe mitral valve regurgitation and a higher risk than smoking. It means these asymptomatic patients have 10 years on average. That's the answer to the question, "Doc, how long have I got?": 10 years<sup>2</sup>. Before their stenosis is graded as "severe", the risk is lower and they have longer. Aortic stenosis may take 10, 20, 30 years to progress to severe.
But once symptoms develop and no surgery done, that's the lower curve. On average those folks only had 3 more years (50% gone at 3 years) after the onset of symptoms. The downhill slide is so fast, in fact, that about 4 or 5 percent of patients who scheduled surgery at this point died while waiting<sup>1,3</sup>. Oof.
The bottom line here is: if you have aortic stenosis, have a frank discussion with your doctors about the timing of surgery. Take a copy of "The Guidelines" (see my June 30 post) as a conversation prop and ask the doctor to go through the charts and recommendations. The choices will typically be between scheduling surgery once the grade is "severe" (when you start experiencing a 5% per year risk), or when symptoms develop - when you have a 15-20% risk per year<sup>4</sup>. In some cases surgery may not be an option. I am not a medical doctor, but in my view earlier surgery is better than later<sup>5</sup>. By a lot.
Keep the beat -- DVB<sup>6</sup>
1. DS Bach, D Siao, SE Girard, C Duvernoy, BD McCallister, Jr, SK Gualano, Evaluation of Patients With Severe Symptomatic Aortic Stenosis Who Do Not Undergo Aortic Valve Replacement: The Potential Role of Subjectively Overestimated Operative Risk, Circ Cardiovasc Qual Outcomes. 2009;2:533-539. Available as a pdf <a href="http://circoutcomes.ahajournals.org/content/2/6/533.full.pdf">here</a>.
2. Here's the calculation. How long do I have means what is my life expectancy, that is when have half of the people in my condition have died. At a loss rate of 5% per year it takes 10 years to lose 50%: 5% per year x 10 years = 50%.
3. DS Bach, N Cimino, Unoperated Patients With Severe Aortic Stenosis, ournal of the American College of Cardiology Vol. 50, No. 20, 2007. This is an unrefereed correspondence, available <a href="http://content.onlinejacc.org/data/Journals/JAC/23106/08011.pdf">here</a> as a pdf.
4. Suppose you have just scheduled surgery for AVR (aortic valve replacement) because symptoms have developed. The surgery date is 3 months in the future, a quarter of a year. Since your mortality risk is as high as 20% per year and you are experiencing that risk for 1/4 of a year it stands to reason that there is a 5%-ish chance that you will die before your surgery date: 20% risk per year x (1/4) year = 5% risk. This pre-operative wait risk is <i>bigger</i> than your operative risk!
5. I'd think that there is an opportunity here to significantly enhance overall survival by adopting a different way of scheduling AVR surgery that decreased the time between deciding surgery was needed and the surgery itself. This could save up to 5 patients per 100, which really matters if you are one of them! But my reading of these journal pages is that most folks are waiting months. It would pay off to jump at any chance to move AVR surgery up (that didn't add some other, bigger risk).
6. Debbie A asked for my take on aortic stenosis with and without surgery. This post is about what happens without surgery, I'll show the improvement in survival odds with surgery later on. The improvement is quite impressive, but not quite as good as for mitral valve repair. However, new valve-sparing surgery options and catheter-based valve replacement techniques are coming on line that keep getting better.
What happens if I don't get my mitral valve fixed?
Journal posted on July 15, 2012
This post is for you if you are diagnosed with severe mitral regurgitation and are facing surgery. You may be having thoughts like this: "Heart surgery is scary, and I'm getting really anxious. It is going to be beyond unpleasant and will take me months to recover. And I might die. Do I really have to have surgery?" Yes, you do. Here's why.
First of all, you are not alone. We're here for you on the HV journals. And every year tens of thousands of folks in the US have their mitral valves repaired or replaced. We've all faced the same thoughts, anxieties, and decisions that you face right now. By now there are hundreds of thousands of us. Choosing to live.
There are 2 aspects to making the choice. First is, consider what happens if you don't have surgery. Second, consider what happens if you do.
In a nutshell, patients who decline surgery have a roughly 5 times higher death rate than those who undergo surgery, and they have a life expectancy of maybe 10 years. That's far worse than smoking, which increases risk of cardiac death by 3 times<sup>1</sup>. Hate to think about smoking with a bad valve - don't do that. On the happy side, patients whose mitral valves are repaired prior to onset of symptoms have their full life expectancies restored.
So that's the nutshell and likely what your cardiologist told you. But if you are like me, just being told the facts in a nutshell is a little too pat and doesn't help allay the anxiety. To do that, I have to <i>know</i> in my bones the what-if's, ponder them, mull them over, do the math, come to terms, and really understand that the choice of surgery is the best, smartest, even most exciting thing I can chose. I mean, it is exciting isn't it? I've got this fatal disease and there's a full cure available. Too bad it's not as simple as a pill. I can live with that. In fact, whatever it takes. Bring it on.
Here's the scoop on untreated severe mitral regurgitation. While mild regurgitation is fairly common and often quite stable, for an unlucky few of us it progresses to severe status. Often this is the result of a ruptured cord, which allows the valve to prolapse, as in my case. Once the regurgitation is severe, which essentially means that a significant fraction of the heart's pumped blood volume is going backwards from the left ventricle to the left atrium, over time the structure of the heart adapts, and then eventually runs out of adaptation. Basically the heart has to enlarge so it can pump enough blood forward considering so much is going backward. Atrial fibrillation commonly begins when the left atrium enlarges as a result of the backwash. As time goes on the left ventricle continues to enlarge to maintain enough forward flow. Eventually heart muscle dysfunction sets in, which diminishes the heart's ability to pump at all. At this point common symptoms are angina, shortness of breath, and strong palpitations. Over time further loss of heart function leads to heart failure and the damage becomes irreversible. In four studies described in the classic textbook "Brunwald's Heart Disease"<sup>2</sup> all initially untreated patients were dead or forced into surgery after 10 years. So, if you ask the doctor how long you have without surgery: 5 years, 10 at the most. Patients with severe mitral regurgitation who do not undergo surgery at all have 55% survival at 10 years<sup>4</sup>. And since they are living with declining heart function, their quality of life is constantly becoming less and less. End stage heart failure ultimately ends their lives. That's up to 10 years of ever increasing anxiety, with a point of no return along the way. Don't choose that.
And here's the scoop on full restoration of normal life expectancy. This conclusion comes from a 1994 study<sup>4</sup> that looked at, among other things, late term survival of 409 mitral valve repair and replacement patients (average age 64) who underwent surgery between 1980 and 1989. In other words, a long time ago when practices were not as advanced as today. So the story today is very likely better than what they reported. First some preliminaries. In a previous post (July 3, 2012) I described how to read and understand survival curves. They show how many patients are left from an initial population as time goes on and they drop out. Here's the survival curve aka Kaplan-Meier curve for mitral valve repair <i>and</i> replacement patients.
The solid line shows the survival curve for an age-matched reference population, normal people. They slowly die off as time goes on. Since the average age of the group was 64, their mortality rate was about 3% per year. The dashed curve shows the surgical patients' survival curve. A couple of things to note. First there is a sharp drop of about 7% right at the beginning. This was the operative and near-operative risk back then, about 25 years ago. It is now much better, and in some centers has recently been zero over many hundreds of surgeries, so don't be scared off by that. Second, after the sharp drop the curve is parallel to the reference population curve. That means patients are dropping out at the same rate as the reference population, and that means that their life expectancy is the same as the reference population once they survive the surgery. This chart is the origin of the wisdom that successful surgery gives you back your life expectancy, on average.
That on average bit is interesting. Patients in the study who were asymptomatic and had healthy ejection fractions did significantly better than the reference population! Even after accounting for peri-operative (operative and near-operative) mortality. Wow. And remember, the perioperative mortality rate is now much lower. The authors did not venture to explain why the ongoing mortality risk is lower than average in this group, but one idea is that these folks learned a lot about heart health in the aftermath of their "adventure" and adopted heart-healthy practices. Whether it was by this manner or another, they reduced their overall mortality rates by about 30% compared to average. Talk about a bonus prize - available to those who bite the bullet and have surgery before symptoms arise.
Another aspect of on average is that the study group contained a large number of mitral valve replacements (214) compared to the number of repairs (195). We now know that repair is superior to replacement<sup>5</sup>, so current patients who undergo repair prior to the onset of symptoms have most excellent outcomes, especially if they have their surgery done at a center of excellence.
Now that's something to get excited about!
1. See <a href="http://www.cdc.gov/tobacco/data_statistics/fact_sheets/health_effects/tobacco_related_mortality/">the CDC page on smoking and mortality</a>. Smokers live 14 years less on average than non-smokers and smoking-related economic costs exceed 150 billion dollars a year (data from 1995 to 1999), about two to three times the size of the US tobacco products market.
2. I bought this textbook when diagnosed. Pricey but incredibly broad, deep, and useful. <a href="http://www.amazon.com/Braunwalds-Heart-Disease-Cardiovascular-Braunwald/dp/1437727085">Amazon page</a>.
3. JF Aviernos, BJ Gersh, LI Melton et al, Natural history of asymptomatic mitral valve prolapse in the community, Circulation 106, 1355 (2002). PDF available <a href="http://circ.ahajournals.org/content/106/11/1355.full.pdf">here</a>.
4. M Enriquez-Sarano, AJ Tajik, HV Schaff, TA Orszulak, KR Bailey and RL Frye, Echocardiographic prediction of survival after surgical correction of organic mitral regurgitation, Circulation 90, 830 (1994). PDF available <a href="http://circ.ahajournals.org/content/90/2/830.full.pdf">here</a>.
5. Robert R. Moss, Karin H. Humphries, Min Gao, Christopher R. Thompson, James G. Abel, Guy Fradet and Brad I. Munt, Outcome of Mitral Valve Repair or Replacement: A Comparison by Propensity Score Analysis, Circulation 108, II-90 - II-97 (2003). PDF available <a href="http://circ.ahajournals.org/content/108/10_suppl_1/II-90.full.pdf">here</a>. By now you are an old hand at understanding survival aka Kaplan-Meier curves. Here's the one from this paper with my annotation showing that repairs are superior to replacement (be aware however that a repair is not always possible). The advantage is significant and is thought to be because in a repair the tissues are left intact and this leads to long term heart health.
Some of us are luckier than others. We get told we have a severe heart problem before symptoms kick in. Of course that makes it hard to believe. "Doc, you've got to be kidding." Or. "Must be somebody else's echo you're looking at."
Ah, denial. A river in Egypt.
Why is it that my leaky mitral valve wasn't apparent to me? After all, a goodly amount of the blood from every contraction was going the wrong way. Ought to have some effect, you'd think.
Well, there are a couple of reasons. The first is that my left ventricle, that's the large chamber of my heart that pumps the blood through my body, had slightly enlarged. It's volume was enough bigger that the amount of blood going the right way was still enough to give me enough oxygen except under extreme exertion<sup>1</sup>.
The second is that the heart has an amazing range of capacity. A well conditioned heart/lung combination can deliver 20 or so times the amount of oxygen to the body under maximum exertion than at rest. Wow<sup>2</sup>. So losing only some modest capacity might only affect you when exercising at the top end of your range. And unless you hit that exercise zone regularly, you won't notice until you've lost more than just a little heart function. That's why a treadmill stress test is so telling - it takes you to the limit and shows you where it is.
The day before my stress test I went for an awesome run. It was around the Arroyo Seco flood plain and upcanyon. I remember feeling really good. In the back of my mind though was the thought that I might be having my last workout for a while, so I cranked it out. The next day I made it through minute 12 in the Bruce protocol treadmill test<sup>3</sup>. That's not too shabby. Average for men my age is 9 minutes. But still, looking at the echo the verdict was in: no more working out for me until I was fixed.
I <i>need</i> to move. Trail running, ultimate frisbee, back country skiing, swimming, whatever. Gotta, otherwise I start feeling a little low and slow after a while. Ask my honey. She's been known to push me out the door, "go for a run!" So the no more workouts edict was huge motivation to get myself fixed asap. Plus the not dying part.
At that point I knew I was on the clock. No more workouts meant no more conditioning. And no more conditioning in fact means de-conditioning. De-conditioning meant my extra heart capacity would shrink as I approached surgery. The longer I waited, the less capacity<sup>4</sup>. The less capacity, the bigger the risk. So that was even more motivation to get on the stick and figure out my surgery plan.
I did get my cardiologist to agree it was OK to take a stroll around the block. So I did lots of those, a couple a day. Parked at the way far corner of the parking lot at work. Best of all were the "strolls" on skis around a "block" of the forest on old abandoned snow-covered roads<sup>5</sup>. Probably cheating on that one a bit. But it kept me somewhat conditioned and my heart capacity above the critical line, and I knew that would be important for the surgery. I also knew exercise would be the key part of my recovery plan and the better base I started with, the better that would go.
My most recent stress test was this last October, five and half months post mitral valve repair. I went 13 minutes with the Bruce protocol, about 16% higher exertion level than my before test. That's average for a 25 year old guy, under half my age. Not bad. Thanks to my ongoing exercise program I could probably do even better today. And, by the way, the exercise is keeping me healthier. I haven't been sick since surgery - 14 months, maybe it's because exercise boosts the immune system. Gotta love it.
<i>keep the beat</i> -- DVB
1. I did feel I was slowing down a bit under maximal exercise, but chalked it up to normal aging. In retrospect though, that dizzy feeling when doing suicides was probably a warning sign.
2. A big car engine might put out 25 horsepower at idle (800 RPM) and 300 hp at 6000 RPM. If it were like your body then for the same idle speed and idle power, at max that engine would be 500 hp at 2,000 RPM. Monstrous!
3. This is a treadmill test where they start you slow and level and increase the speed and incline every 3 minutes until you cry "Uncle!" See the <a href="http://en.wikipedia.org/wiki/Bruce_protocol">wikipedia article</a>.
4. Capacity drops about 4% per week when going from jogging to just walking: R. H. Dressendorfer, B. A. Franklin, J. L. Smith, S. Gordon and G.C. Timmis, Rapid Cardiac Deconditioning in Joggers Restricted to Walking, Chest 112, 1107 (1997); pdf <a href="http://chestjournal.chestpubs.org/content/112/4/1107.full.pdf">here</a>. After 2 months, there's a 20% reduction in VO<sub>2</sub>max in highly conditioned subjects who stop exercising: W. H. Martin III, MD, E. F. Coyle, S. A. Bloomfield, A. A. Ehsani, Effects of Physical Deconditioning After Intense Endurance Training on Left Ventricular Dimensions and Stroke Volume, Journal of the American College of Cardiologists 7, 982 (1986); pdf <a href="http://tinyurl.com/6pm9pmh">here</a>.
5. Yup, it snows in LA. Up at 7000 feet in the mountains north of town.
The sudden shock of learning I had a serious heart problem was because I was expecting more time with my wife and kids. I wasn't ready to go, not by a long shot. What a jolt.
I was thinking I'd have a lot more time because for a while I've been keeping track of life expectancy. Two things had me curious about how long we all had. Firstly, life expectancy is increasing - life expectancy at birth grew by over 28 years between 1900 and 2007<sup>1</sup> and continues growing. Secondly, if medical advances cause life expectancy to grow fast enough<sup>2</sup> then instead of growing by two or three months per year, it will eventually grow by a full year per year. Think of that. Every year puts off the inevitable for a year. Makes it not so inevitable. I expect my kids to see this inflection point. I even had a hope I'd see it too. But then WHAM. Severe heart badness in that wonky mitral valve. Not what I was expecting. I thought we'd have longer, my sweet.
Happily mitral valve wonkiness is fixable for most and restores normal life expectancy when repaired. They really should tell you that your heart problem is ninety-some percent fixable to good as new before they tell you the horror story<sup>3</sup>.
All this is a prelude to introducing one of the most powerful tools for evaluating the value of medical treatments, lifestyle choices, etc: survival curves, also known as Kaplan-Meier curves. I'll be using these in future posts to look at surgical outcomes and whatnot, so listen up. The curves show how many individuals are left from an initial population as time passes. Computing them is pretty complicated<sup>4</sup>. Luckily we just have to look at them, and that's easy. Let me walk you through an example. It's not directly valve related but has much broader relevance:
These are Kaplan-Meier curves for men's survival against all causes of death according to a 2009 study using half a million people. This is a real eye-opening study. First notice that the data are <i>stratified</i> according to BMI (a measure of under/overweight-ness), that's why there are multiple curves. The curves show the chance of reaching a given age for various BMI cohorts. Here's how to read the plot. At each year the height of a curve says what fraction of men in that curve's BMI cohort are still alive with that age. As time goes on, men die in each cohort and the curve drops to the right. For example, at age 60, 91 percent of the blue population of men (top curve) are still alive. Those are the guys who have optimum BMI, around 24 kg/m<sup>2</sup>. It's a just-right number, you don't want your BMI to be much larger or much smaller. Knowing your height and weight you can <a href="http://www.nhlbisupport.com/bmi/">calculate your own BMI</a><sup>5</sup> easily. Hey, mine's 23, not bad. What's considered obese? That would be BMI over 30.
Now here's the eye-opening thing. Check out how many of the very most obese guys (BMI over 40) are still alive at age 60. It's only 76%. They are represented by the lowest curve, the one with little red circles. They are two and half times more likely to die by age 60as the guys with optimum BMI<sup>6</sup>. 60 is not even retirement age. Thanks very much for your Social Security contributions, sorry you don't get any back.
BMI over 40? Only about a third as likely to hit 80. And only one fifteenth as likely to hit 90. Ouch. This is why the obesity epidemic is considered a public health crisis. For you ladies the situation is a little better, but you're nowhere near off the hook. As for skinny skinny, skinny folks - the chart doesn't show your curve, but according to the paper having a BMI of 17 is as bad as having a BMI of 37. That's between the bottom two curves, pretty ouch too<sup>7</sup>.
This brings me pretty close to full circle from where I started. And looking at the length of this post it's about time. The life expectancies published by the government are population averages, they include obese people. Obesity rates are increasing. Why? Calorie-rich low cost foods are more available and there are more opportunities for sedentary lifestyles. Maybe for other reasons too. All else being equal, increasing obesity would be shortening the average lifespan. But nationwide, on average, we are living longer. Given that the obesity rate is already 30%<sup>8</sup> it means the optimum BMI folks are gaining life expectancy way faster than the average of two or three months per year<sup>9</sup>.
That's a club I want to be in! You too, I'll bet. Glad I got that wonky valve fixed. My darling, I'm hoping we still have a long, long time together.
<i>stayin' alive</i>-- DVB
1. Your tax dollars at work produce the <a href="http://www.cdc.gov/nchs/products/life_tables.htm">US Life Tables</a>, an annual publication by the CDC.
2. With the advent of DNA sequencing and related technologies, medical science is becoming an information science. As such it will become subject to a kind of Moore's law of exponential growth, like computer technology's rapid advancement. Only two factors of two are needed for the average life expectancy to reach the 1-for-1 inflection point. In the computer realm that amount of improvement only takes 3 or 4 years.
3. Average lifespan after diagnosis of severe mitral regurgitation is 5-10 years, give or take. Bah. Subject of a future post.
4. Kaplan, E. L.; Meier, P.: Nonparametric estimation from incomplete observations. J. Amer. Statist. Assn. 53:457–481, 1958. Available as a PDF <a href="http://tinyurl.com/7496uv7">here</a> for the geekiest among us.
5. More of your tax dollars at work. Explore that site. Tools to live by.
6. Here's the math: 100%-91%=9% gone in the optimum BMI group (blue line/squares) vs 100%-76%=24% in the high BMI group (red dashed line/circles). Then the ratio 24% divided by 9% is about 2.5.
7. These curves say there is a clear correlation of lifespan on BMI, that very high and very low BMI are mortality risk indicators. The curves do not say that changing your BMI will alter your lifespan directly. To show that rigorously would require studying people who changed their BMI and looked at how that change affected their lifespans compared to people who didn't alter their BMI's. On the other hand, the simplest explanation for the data is that indeed BMI does directly affect lifespan, so a prudent approach would be to <i>safely</i> modify your BMI to be in the optimal range. Because of human biology, this is very difficult for some people to do, but as you can see has large potential payoff.
8. The Center for Disease Control's <a href="http://www.cdc.gov/obesity/data/adult.html">page on obesity in America</a> includes a year-by-year animated map showing the spread of the obesity epidemic.
9. I haven't done the calculation or gathered up the right data to do it, but I'd expect the cohort with BMI between roughly 20 and 30 to be extending lifespan faster than average while those below 20 or above 30 to be extending lifespan less than average. Obese people are probably living longer now than obese people used to, but the obesity epidemic means that non-obese people with longer life expectancies are becoming obese people with shorter life expectancies as they gain weight.
I got a couple of good things out of my first cardiologist. Now mind you he was pretty gruff. And literally never heard of listening. Not much for explaining either. Nope, not exactly my kind of guy. But he did motivate me to be my own advocate and he did point me to The Guidelines<sup>1,2</sup>. If you've read Adam's book and visited a bunch of websites and are still thirsty for more, then The Guidelines are for you.
The American Heart Association and American College of Cardiologists Guidelines for the Management of Patients with Valvular Heart Disease</a>
Frankly it's a hard read, end to end. Written by cardiologists for cardiologists so quite a slog. Here's how I approached it: picked out just the parts needed using the fantastic table of contents then used wikipedia to decode the secret society jargon. Ah, just like studying for college all over again!
But its real value is as a conversation prop. Print it out and take it with you to your cardiologist, or have them dredge up their dog-eared copy. They've read it and know it inside out. Ask them to take you to the right section and go through it with you while discussing your own valves. Make notes on it. Have them thoroughly explain the what's and the why's. Make sure you are satisfied that you understand.
These are just guidelines and every patient is different. Every doctor is different. Sometimes the best thing to do might not be one of the guidelines, it might be a deviation from the guidelines. Like it might be new and not yet rolled in. But you deserve to know that the judgement behind the deviation is sound. Confident that it's backed up by evidence. And that's where my first cardiologist strayed. He strayed away from The Guidelines without convincing me it was sound. That's why I have a new cardiologist.
The Guidelines are the distilled wisdom and knowledge from decades of heart valve medicine. Vast treasures were spent learning what's in the guidelines. Trials, errors, studies, science, engineering, art, careers and lives. Millions of patients, thousands of doctors. Each patient bearing a gift of experience and knowledge for the doctors. Each doctor bearing a gift of care and cure for the patients. Yin and Yang. All tied together into a book of goodness and life.
<i>Learn and live</i> -- DVB
1. I've pointed out The Guidelines in a bunch of HVJers Guestpages. I'd appreciate hearing from any who've used them and what your experience was.
2. The American Heart Association requests that this document be cited as follows: Bonow RO, Carabello BA, Chatterjee K, de Leon AC Jr, Faxon DP, Freed MD, Gaasch WH, Lytle BW, Nishimura RA, O’Gara PT, O’Rourke RA, Otto CM, Shah PM, Shanewise JS. 2008 Focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients With Valvular Heart Disease). Circulation. 2008;118:e523–e661.
Many, if not most of us got started on the journey that led us here when the doctor heard a murmur when doing a stethoscope exam. "Heh, you got a murmur!". That's what happened to me - I was told I had a murmur when I was a kid.
Murmurs are fairly common, and often the doctor will tell you not to be concerned, its only a slight one, benign. But if you're reading this chances are your murmur is now fairly prominent, no longer benign. Or, in my case, you could <a href="http://tinyurl.com/6sc4c8o" target="_blank">hear</a> it across the room.
Sounds, of course are vibrations, which in turn are motions. The heart is in continuous motion as it beats, blood is in continuous motion as it flows, and valves are in continuous motion as they open and close (or just flop around, bah). There's a lot going on! A trained ear can pick out all sorts of things from listening to the beat. I have this image in my mind of cardiologists-in-training spending hours upon hours listening to audio recordings and roaming hospital halls cornering hapless visitors to listen in and hone their skills. "Yup, the guy visiting in 233 has a galloping systolic whack-thwap grade 3, you ought to check it out."
The day my second opinion cardiologist put the earpieces on me and had me listen was the day it all became real. Not much is more primal than the old heart beat. Going awry. Talk about convincing. And it sets you up for a huge joy when you listen to your fixed heart. I highly recommend giving yours a listen. Let your honey listen too, before and after. Wow.
<a href="http://depts.washington.edu/physdx/audio/normal.mp3" target="_blank">This</a> is what a normal heartbeat sounds like, two well-separated beats with near silence between<sup>1</sup> . And here below is a time-trace of the sound from a single heartbeat, which shows the pressure variations on millisecond timescales over a period of about one second<sup>2</sup>.
The heart is a well-honed organ. Hundreds of millions of years of natural selection have weeded out variations that are less than the fittest, so the blood's flow through the heart has minimal turbulence and minimal resistance. That's why the interval between the beats in a normal heart are pretty silent and the beats themselves are short and well defined. Turbulent flow is noisy, takes a while to decay, and gives rise to murmurs. Bad valves make turbulent flow, lots of it. Ergo, bad valves produce heart murmurs. And lucky for us, dangerous heart murmurs are easy to find using a stethoscope.
<i>Listen to the beat</i> -- DVB
1. Always an adventure to embed links in a blog since the "away file" could disappear. I found these sounds using the google search terms: heartbeat audio files murmur. Man, I love Google. The linked file is from the University of Washington Department of Medicine site, which provides a whole <a href=http://depts.washington.edu/physdx/heart/demo.html>collection</a> of sounds for various valve disorders.
2. From Debbal and Bereksi-Reguig, "Frequency analysis of the heartbeat sounds", Biomedical Soft Computing and Human Sciences, volume 13, page 85 (2008). PDF version available <a href="http://www.f.waseda.jp/watada/BMFSA/IJBSCHS/Vol13N1/BSCHV13N01_PR13.pdf">here</a>.
After the doctor tells you that you have a fatal condition if left untreated and then tells you that with surgery the survival odds are 98% that sounds pretty good. A hundred people walk in the door with your same condition and 98 walk out. Survival odds are what doctors experience.
Your thoughts rightfully should be on the remaining 2%. Which was your first thought: "Yay! I've got a 98% shot!" or "There's a 2% chance I don't make it."? Most of us go right to the 2% side of the equation. Mortality rates are what heart valve patients experience and are rightfully concerned about.
Here's the deal. Heart valve surgery is already good enough that there's no further room to double the survival odds. It only has to fix half the patients to do that. Heck, it started out being better than that in the 1960's.
But the mortality risk has indefinite room for being cut in half time and time again. Eventually the mortality risk just equals that for living another day with a bad valve. Won't that be cool: just as risky to go in to get your valve fixed as to do anything else that day. Nobody would think twice about it. Maybe it will be free and won't hurt either!
Well, we're not there yet and it will take quite a while at the same average percentage-wise improvement in the death rate per year we've had since the beginning, which accounted for about a 10x improvement in the average mortality risk over 50 years<sup>1</sup>. Facing valve surgery? Wouldn't you like to travel 25 years into the future and get it done when the death rate is down by more than 3x?
There is a time machine for this, it turns out, and it's called managing your medical risk. It comes about because you can do better than the average. Half of all patients do already! By actively seeking out the best options and making the best choices from among them you can reduce the odds of your dying before, during, or shortly after your surgery by a factor of few - compared to going with the flow and letting events happen as they will.
You owe it to yourself and your loved ones to get this advantage, so always be thinking about what you can do to get an even better edge. So do some research, ask questions, particularly about choices and risks. Being educated is known to improve lifespan<sup>2</sup>, presumably because then you make better choices, so get educated. Knocking your mortality risk down by a percent or a few tenths is hugely worthwhile. <i>It's your life!</i> -- DVB
1. I am planning on discussing the actual risk numbers in a future jounral entry. For now be aware that numbers that doctors quote are backward looking, they are the results from studies that were done in the past. Your odds are forward looking, and to the extent there are improvements, your odds will be better than experienced in the past by others with your condition.
2. Being educated significantly lowers your overall mortality risk. Plug in to some targeted education and get even more of this edge. Read a <a href=http://tinyurl.com/8xhlwmq>news item</a> on this topic, or the <a href=http://tinyurl.com/78ac6wj>statistical report</a> from the CDC.
I'll tell you, facing heart surgery really got me thinking about risk. The risk of dying stops being an abstract thing when you're facing the possibility. In my work I deal a lot with the other kind of risk, the risk of not meeting some goal, or the risk of loss. Not quite the same thing. Risk of dying is personal. Real stark and real personal.
On our projects we talk about "buying down risk". It works OK with things that aren't so important like time and money and goals, at least when the risks are understood.
But its not a smart strategy at all when dealing with your life. Nope, when you are dealing with existential threats you need to play a different game. The name of that game is work like a dog to discover all the risks and do whatever you can to eliminate them, whatever it takes. And keep doing this until you run out of time or resources. This is the strategy game-theory geeks call <i>minmax</i>. As a heart patient minmax strategies are among your best friends because they <i>min</i>imize the <i>max</i>imum bad that can happen to you.
A simple example: The phone rings and it is your surgeon's assistant. There's an opening for surgery tomorrow. You should take the offer because with your valve condition you could die before your scheduled surgery in 2 weeks. Now, it is kind of sudden and maybe you haven't taken care of your will yet, or made arrangements at work, or you really wanted to be at daughter's graduation next week. No matter, none of those things can outweigh the benefit of sidestepping the chance of dying while awaiting surgery (which is about 1/4% in this case).
So when making choices, think: am I avoiding a risk without taking on a new one? If the answer is yes, then it's a good choice. On the other hand if you are accepting a risk for convenience or comfort, then that's a bad choice from a survival perspective.
Hello my friends. After lurking in your guest pages for over a year it's time for me to start my own journal. Here I'll explore being a heart valve patient from an experiential and evidence-based perspective. But before starting off on this new journey I give thanks to Adam and all you HVJ bloggers for helping me through my own valve repair one year ago. Our community is an incredible example of the human spirit's grace and generosity in the face of adversity. Words cannot say how much you've enriched my life with your courage, wisdom, humor, tenacity and compassion. Thank you all. -- DVB