HCM for 30 years recently tested positive for MYBPC3 gene

@npfl Thank you for sharing that you had a DNA screening, and it was found that you have the MYBPC3 gene. Did you feel relief that it was found (my naughty gene is as yet unknown)? Your post is extremely informative, especially "...notified my first degree relatives to obtain genetic testing" and the parts about your son and your father. That type of action and observation is what we all need to be mindful of. How did you know to find out if you had HCM over 30 years ago?

Can you explain what you mean by a multi- level conduction disorder? You will be in excellent hands at Mayo Jacksonville! I was diagnosed in my mid-late 50's and had no problems with moderate exercise (walking, gym, paddling, bicycling) until I was 75. When I needed a septal myectomy at that time, my physical shape made for a surprisingly easy recovery - at 6 weeks I was walking 3.1 mph on a treadmill and walking 5K with my walking club. As a retired NP, you have learned much about this terrible disease and probably know excellent questions to ask your doctor. Please stay in the loop and share your experiences as you progress on this journey.

I was diagnosed on my retirement physical from the Navy in 1995. I had become increasingly dyspneic while on the Nordic Track. My echo findings were consistent with HCM. That diagnosis was confirmed at NIH in 1996 where NIH postulated my father probably had HCM since he went into chronic afib at age 51. He subsequently needed a pacemaker in his 70s. In 2004 a LGE MRI confirmed HCM though my echo was WNL, probably from the Atenolol 50 mg that had been started. I was asymptomatic at the time. I continued to exercise as per NIH recommendations on the Nordic Track, then elliptical until the late 2000s when I once again became symptomatic. My NT-proBNP was found to be in
300s and I had developed a 1rst degree AV block. UF postulated I was obstructing while using all four limbs and exercising upright. UF did encourage genetic testing, which I refused. My son was a very good student and my husband and I thought he might be interested in the USNA; positive results would preclude that. Additionally, I didn’t think it would change anything in my treatment. I switched to a recumbent bike and ultimately , after another complete cardiac w/u to a water rower. By the early 2020s I developed a progressive conductive disorder including SSS, very long AV delay and a strong possibility of a delay distal to the AV node. Ultimately I required a dual chamber pacemaker.
I agreed to genetic testing at Mayo primarily for my son, who was looking at life long cardiac monitoring . I thought I would probably be VUS but turned up positive for MYBPC3. On initial screening my son’s ECG was abnormal and he was referred for an echo. His ECG looks disturbingly like mine at diagnosis. I’m sure he is genotype positive. There is increased penetrance with males, so I am concerned. Fortunately, no SCD in my family. I live in Jacksonville and I have transferred my cardiac care to Mayo as my conductive disorder is unusual in HCM patients without septal reduction procedures. My current cardiologist and EP feel my long history of vigorous exercise has provided some protection from the adverse effect of HCM. That is very different from when I was diagnosed 30 years ago.

Glad you are being watched so closely and receiving excellent care.

Prior to my diagnosis last year, as my exercise capabilities diminished — I thought it was aging — the last exercise to decline was rowing. I suspect it was because my heart was closer to the horizontal plane of the rest of my body so it was easier to circulate blood to the muscles needing oxygen, but the complex interactions of blood pressure, exercise, obstruction, etc. remain a mystery to me. By comparison, just bending down to pick up a rock at the beach could leave me feeling slightly faint and breathless. One myectomy later and I’m back to “normal.”