Hello! My name is Dr. John Grehan and I am a cardiac surgeon having graduated from University of Minnesota in 1995. To date, I have performed approximately 1,000 cardiac surgeries, of which 600 involved heart valve procedures. I regularly perform surgery at United Heart & Vascular Clinic. Read more...
I believe my greatest strength is my passion for helping patients with valve disease.
That passion helped me develop a unique, team-based approach to heart valve surgical care that provides patients, their family, and friends, a comfortable surgical experience with great, long-term results. I am able to effectively communicate with you in a manner that allows you to fully understand what is wrong with your heart and how that has led to your current condition, and what may lay ahead for you if surgery is not undertaken. I also am able to provide you with a clear understanding of the procedure required to fix your heart and what to expect in the post-operative period.
The extensive exposure to, and experience in performing heart valve surgery I received during my cardiothoracic surgical training at the University of Michigan, provided me with a solid foundation to build a practice specific to heart valve surgery. Using these fundamentals, I have been able to modify my practice to utilize minimally invasive approaches for treating valve disorders including aortic stenosis and mitral regurgitation (also known as a leaking heart valve) in order to help patients recover faster. I have experienced great success with these approaches and have found the process of implementing these techniques into my practice very rewarding.
"Dr. Grehan was very informative before and after the surgery. I highly recommend him."
-- Kent Christopherson, heart valve surgery patient
"Dr. Grehan was excellent!"
-- Tom Cohoon, Aortic Valve, Mitral Valve, Valve Repair, 08/18/2016
-- Tim Peterson, Aortic Valve, Valve Repair, 04/25/2016
-- Jeffrey Kile, Aortic Valve, Root Replacement, Maze Procedure, 02/04/2016
-- Rita weiss, Mitral Valve, Valve Repair, 11/09/2015
I would definitely recommend Dr Grehan and his staff!"
-- Steve Beyl, Mitral Valve, Valve Repair, 11/03/2015
-- Sarmita Peterson, Mitral Valve, Tricuspid Valve, Valve Repair, Maze Procedure, 08/28/2015
-- Wayne Weierke, Aortic Valve, Valve Replacement, 08/19/2015
-- Karen Meyers, Aortic Valve, Valve Replacement, 08/10/2015
-- Robert Garrison, Mitral Valve, Valve Repair, 08/07/2015
Thank you Dr. Grehan, doing well in my recovery and I'm sure it's aided by your attention to details and skills during my surgery and in hospital recovery."
-- Gary Houghton, Mitral Valve, Valve Repair, 08/06/2015
-- Robert Bergstrom, Aortic Valve, Valve Replacement, 03/03/2014
Our family was quite apprehensive to go thru the surgery again. He did an aortic root replacement, put in a tissue aortic valve, did a single bypass, and put a clip in her heart. She is a 74 year old women. The surgery lasted 7 hours and the recovery has went well. Dr. Grehan and his entire staff were wonderful.
I'm happy to report that my Mom is recovering quite nicely and we look forward to having her with us for many more years. I would highly recommend Dr. Grehan."
-- Gloria Peterson, Aortic Valve, Valve Replacement, Root Replacement, 02/28/2014
-- JANICE MATZEK, Aortic Valve, Valve Replacement, Median Sternotomy, 02/04/2014
Dr. Mahoney recommended that we take this conversation to Dr. John Grehan who does heart valve replacement/repair with great success. My family and I were impressed with Dr. Grehan's knowledge, experience and compassion to help a patient who was in heart failure. He explained in depth the detail and with patience and confidence the procedure and the risks that could be involved. After he explained the whole process there was no doubt in my mind or of of my family that he was the doctor to do the surgery.
I came through the surgery with welcoming success. Dr. Grehan and his team monitored my recovery and progress daily and most often twice a day. We came to know Dr. Grehan well because he was always willing to take time to answer our questions and talk about my future. He is, without a doubt, knowledgeable and compassionate about his work to help patients come through heart surgery with success. His bedside manner comes with a wonderful spirit. It was easy to feel like I was his only patient.
Several months after the aortic valve replacement success, the doctors discovered that my tricuspid valve had developed a leak, regurgitation, and again my heart was not working properly. The only way to fix this leak was to have another valve replacement/repair surgery. I was retaining fluid. Not much time left to wait. Again, we discussed the surgery with Dr. Grehan and Dr. Mahoney. In his calm and and reassuring manner, Dr. Grehan explained that this surgery would be even more difficult and involved more risks as well as more painful. He would have to do a thoracotomy; enter the heart between the ribs on the right side. He talked about what needed to be done and how he would accomplish it. He spoke with confidence of knowledge that assured me that he was the doctor who knew how to do this job.
Knowing that this was, again, a difficult decision for my family, we were advised to seek a second opinion. We did. We were advised that we couldn't have a smarter surgeon for this job. On January 25th, 2014 mission accomplished with success! Dr. Grehan and his team continued to monitor my recovery with daily visits and updates to my family and me.
My family and I highly recommend Dr. Grehan as the doctor who knows how to give more life to a failing heart. I felt that he gave me the same kind of care that he would give his father. Dr. Grehan's knowledge and compassion for his work is can be reassuring to any patient with heart failure. He works with an excellent team of doctors, nurses and assistants. When I was ready to be dismissed from the hospital, Dr. Grehan came with his whole team to wish me well. I could not have asked for a better team."
-- William (Bill) Schunk, Aortic Valve, Tricuspid Valve, Valve Repair, Valve Replacement, 01/25/2014
-- paul prusak, Aortic Valve, Valve Replacement, 01/09/2014
-- Tim Simon, Aortic Valve, Valve Replacement, 12/02/2013
Should anyone I know need a recommendation, I will not hesitate to refer them to him for their heart procedure.
Thank you for making the biggest decision of my life easy, the result routine, and for allowing me to return to the quality of life I'm accustomed to."
-- Dave Monn, Mitral Valve, Valve Repair, 11/27/2013
-- James Tjornhom, Aortic Valve, David Procedure, 09/10/2013
-- Kent Christophersen, Mitral Valve, Valve Repair, 09/06/2013
-- Nancy Johnson, Aortic Valve, Valve Replacement, 05/29/2013
-- David Lindberg, Aortic Valve, Valve Replacement, Mini-Thoracotomy / Port Access, 01/02/2013
Either way it had to be done however if there was a chance for a replacement I had to make a decision very quickly. After talking with Dr. Grehan, his level of confidence lead me to believe that if there was a chance he was the man to do the procedure. I came through wonderfully and the repair was a complete success! Following the surgery and 12 hours into recovery my lungs filled with fluid and John was summoned to the ICU. Within minutes John was able to put a drainage tube into each of my lungs to drain the fluid and I was able to breath normally again. It ended up being only a minor set back and he and his staff regularly checked in on my to make sure that the drainage was well under control.
I can not say enough about this surgeon and if I had to do this procedure all over again John Grehan would be my surgeon of choice. My recovery was quick and I was already working from my home on my computer 2 weeks later. 7 weeks to the day I had my surgery I was back at work full time feeling better than ever. I travel for my career and at 8 weeks I was walking through the airport and getting on a plane.
At first when they suggested that I have the surgery immediately I tried to prolong it using work as an excuse. It was really more the fear of the surgery. My biggest fear was the breathing tube that you wake up with following the procedure. I am very claustrophobic and had a lot of anxiety about waking up with that tube. The pre-op nurse mentioned to my husband that when I awake he should ask the ICU nurse how much longer it would be before it could be removed so that my husband could say..."the tube will come out in about an hour". That actually helped put me at ease and between that and the groggy state I was in I honestly don't even remember it being in or anyone removing it. I was kept very comfortable and before I knew it I was going home. My fear about the whole process was for nothing. I won't say that there isn't any pain involved with recovery and those first few weeks I felt pretty rough, but considering what I had gone through it was pretty minimal and now 10 months later I don't really remember much of it. I'm just great full that I feel so good. My breathing problems for the most part have subsided. I can now walk up steps without huffing and puffing and my energy level has improved greatly.
I was told that my life-expectancy has gone back to a normal healthy women in my age category and for that I applaud everyone that had a hand in my care.
Eight months after the surgery I was out riding my Harley and going on regular daily walks with my dog, a yellow lab that pulls too hard on the leash. Life couldn't be better! "
-- Linda McCann-Rugo, Mitral Valve, Valve Repair, Median Sternotomy, 12/15/2012
-- Michael Dressen, Aortic Valve, Valve Replacement, Root Replacement, 03/26/2012
Specific to heart valve surgery, you should know that I have several specialties including:
In addition, I have research and clinical interests specific to:
Dr. John Grehan, heart surgeon, graduated from University of Minnesota in 1995.
In 2004, Dr. Grehan completed a General Surgery Residency at the University of Minnesota. He then attended the University of Michigan in Ann Arbor, Michigan for his Cardiothoracic Surgical Residency successfully completing this in 2006.
Dr. Grehan is board certified by both the American Board of Surgery and the American Board of Thoracic Surgery.
Additionally, Dr. Grehan is a Fellow of the American College of Surgeons and a member of the Society of Thoracic Surgeons.