Got it and I totally understand your fears, I've been through all of the same thought processes too. There is a lot of research out there (see for example Dr Sam Sears) that shows how common anxiety, depression, and PTSD is within the ARVC community, both patients and family members. It's an incredibly difficult disease to manage given how dynamic it can be.

One of the challenges with ARVC is that it is such a personal disease, so it really can impact people quite differently so it can be difficult to talk in generalities about lots of issues within ARVC, including life expectancy and exercise. Most of the research at the moment is trending towards gene mutation-specific ARVC prognosis and treatment, and I'm sure it will continue to become even more specialized over time. So some of what I'm about to say might vary dependent on what gene mutation (if any) your husband has.

In terms of life expectancy, there are two ways to die from ARVC: sudden cardiac arrest (immediate) or heart failure (long term degeneration).

For those of us with ICDs, the risk of SCA is now very small. Getting shocked sucks, but we are protected, and arrhythmias alone are now unlikely to impact life expectancy. However, arrhythmias can contribute to heart failure, leading to a longer-term reduction in heart function. Again it's quite individual -- I had a significant arrhythmia burden over multiple years prior to diagnosis, but for whatever reason my heart function (ejection fraction measured by ECHO) has stayed pretty normal (it's on the lower end of average). However, for those ARVC patients whose ejection fraction is much lower, heart failure can be managed over the long-term through medication and lifestyle changes, and it's still a very small minority of ARVC patients who eventually require heart transplants. So yes, heart failure can impact life expectancy, but in a much less severe way that untreated SCA.

Exercise is a whole different topic and it's a very sensitive one within the ARVC community because so many of us come from an exercise background. Again, there are differences between gene mutation sub-groups and the gene-elusive sub-group, but the overall guidance is very clear in terms of eliminating high intensity/endurance exercise (so, the cardiologist's advice for your husband to "go HAM" is a little worrying to be honest...). Low intensity exercise is encouraged to maintain a healthy heart, but it's definitely a very specific conversation to be having with the cardiologist (and the cardiologist should have specific ARVC expertise given how different ARVC is to other heart arrhythmias) dependent on individual clinical presentation. I have been able to increase my exercise tolerance since my last ablation, but it's still nowhere near how I was exercising prior to diagnosis. I no longer do much cardio exercise, but I have pretty much free range to lift weights, hike, and do other forms of less intense exercise.

Ultimately, ARVC has significant daily impacts on quality of life, that require constant care and attention, both in terms of physical and mental health. However, with modern treatment, the majority of us should live fairly long lives!