My septal myectomy decision, and 10 things I've learned since.

I had a septal myectomy, with related mitral valve repair, on July 24, 2025, 23 days ago. I’ll relate below how I decided on a septal myectomy and some of what I learned from the surgery.

What follows is a lengthy post, apparently too long for one post on this site, so I’m breaking it into 3 posts, which I hope will work.

This is post 1 of 3.

First, some background:

I am a 73-year-old man. I was told I had a heart murmur when I was in my twenties. From college days forward I have always been physically active. I rode my bicycle across the U.S. at age 22, and regularly rode long and short distances throughout my life (cutting back significantly in the past few years only because of knee pain and neuropathy in my arms). I also regularly skied, downhill and cross-country, and did a fair amount of mountain hiking, swimming, running, gym memberships, and aerobics classes. I had no HCM symptoms (and had barely heard of the condition, if at all) throughout all of this, up until I was in my 60s.

Around 7 or 8 years ago my heart murmur became more pronounced (to my PCP; I never felt it), so I was referred to a cardiologist and after tests including a transthoracic echocardiogram (TTE) and cardiac MRI I was diagnosed with HCM and received regular follow-up monitoring and tests. I still felt no symptoms, despite worsening gradients and other test results, including a septum thickness of 2.3 cm (I believe the high end of the normal range is 1.1 cm).

In June 2024 I first felt HOCM symptoms, an unexplained shortness of breath (SOB) while doing a mild hike at a tourist spot in Italy. I managed fine for the rest of that two-week vacation, as long as I took it slow and regularly rested while walking. When I returned home in July 2024 my cardiologist introduced me to my future septal myectomy surgeon, but I wasn’t ready to agree to surgery where I had been symptom-free until just a few weeks earlier.

Eventually, I reluctantly decided to try mavacamten (Camzyos). I was resistant to the prospect of taking an (expensive) medication, probably for life if it worked at easing HOCM symptoms, without directly treating the underlying cause of the SOB (in my case the over-thick septum and a defective mitral valve). I was on mavacamten from October 2024 till April 2025, but it did not relieve my SOB symptoms enough (or improve my gradients and other test results enough on repeated TTEs and another MRI) to satisfy me or my health providers that it was efficacious, so I opted for the surgery.

Up until my surgery date I had been going to the gym four or five times a week, mostly using an elliptical machine for aerobics and engaging in some light weight-lifting. I hadn’t been pushing as hard as I had been before I first felt symptoms a year ago, but until the surgery I was still getting in a good workout. In the past year, the times when I felt sudden SOB were random and unpredictable, like maybe when I would bend over to tie my shoe, or if I were walking downtown, carrying my laptop in my briefcase maybe a few extra blocks because I couldn’t find a parking space near my destination. The one time I fully fainted (lost consciousness for a couple of seconds) happened to be in July 2025, two weeks before my already-scheduled surgery. I had leaned over to take something out of the refrigerator, and when I stood up I felt woozy. I held on to the nearby countertop, and thought the moment would pass, but then woke up (unharmed) on the kitchen floor after losing consciousness for 3 to 5 seconds (my husband was in the room and heard me fall).

End of post 1. Two more posts to follow.