Joey Wahler (Host): It can obstruct blood flow from the heart. So we're discussing hypertrophic cardiomyopathy, also called HCM. Our guest is Dr. Robbie Wu. He's Assistant Professor of Medicine and Medical Director of the Hypertrophic Cardiomyopathy Program at Tampa General Hospital and University of South Florida's Heart and Vascular Institute. This is Community Connect presented by TGH. Thanks so much for joining us. I am Joey Wahler. Hi there, Dr. Wu. Welcome.

Robby Wu, DO, FACC: Hi Joey. Thanks so much for having me today.

Host: No, great to have you board. We appreciate the time. So first, what is hypertrophic cardiomyopathy?

Robby Wu, DO, FACC: So hypertrophic cardiomyopathy, and we call it HCM for short, is thick heart disease. Now a lot of things can cause a thick heart, and it's a cardiologist's job to rule out the other causes. But in HCM, it's an overgrowth of heart muscle that can significantly limit a patient's exercise capacity and cause a lot of symptoms.

It's really underdiagnosed. Really under-recognized, but extremely prevalent. So our population studies estimate that up to one in 200 people worldwide have this disease and it affects people without any regards to age, sex, ethnicity. We really see it everywhere on planet Earth, and it's really important to diagnose because it's associated with sudden cardiac death, and there are some genetic implications as well.

Host: Absolutely. And so speaking of which, can you tell us about the risk of sudden cardiac death?

Robby Wu, DO, FACC: Well, HCM is the most common cause of sudden cardiac death in young athletes. So when you see young baseball players dying on the field, suddenly, or young basketball players dying on the court, whether it's high school, collegiate, or even professional sports; it's usually because of HCM, and we see a lot about it in the news.

In high risk individuals, we really recommend an ICD or a defibrillator to protect against sudden cardiac death. And so if you have HCM, it's really important to speak with your specialist to see if you need an ICD. Now, not everyone does, but everyone with HCM really needs a thorough assessment to see if they do.

Host: Yeah, no question. To your point, we've heard in the news in recent years a number of occasions where high school and college athletes seemingly healthy on the outside, have died unexpectedly. So you'd mentioned doctor, genetic implications as well. Can you tell us about that?

Robby Wu, DO, FACC: Yeah, so about 30 to 50% of patients with HCM have an underlying genetic predisposition. So this is a disease that can affect generations of families. And in general, the recommendation is to genetically test the patient that has the disease. And if that patient is positive, all first degree family members then should receive testing.

Now, HCM has what we call variable penetrance, meaning if you have the gene, it can cause different outcomes in different patients. So some patients have no symptoms or physical expression, and some patients have profound symptoms and a lot of expression. And then there are those patients that fall somewhere in between that spectrum.

So all that to say, even if you're genetically positive, it doesn't automatically mean that you're going to definitely develop the disease, but it does mean that you should be screened with electrocardiograms and echocardiograms a little more frequently. And if the patients are genetically positive, this is how we approach surveillance with their family members as well too.

Host: And so Doc, I would imagine those joining us are wondering at this point, what are some signs or symptoms of HCM?

Robby Wu, DO, FACC: So everyone describes HCM a little bit differently. Most patients feel shortness of breath, especially when they exert themselves. Some patients feel chest pain. Others describe palpitations. Spells of passing out, or even fluid retention, so it could be really variable. And symptoms are usually due to what we call obstruction, as you mentioned earlier, where the heart is so thick that the blood is having trouble ejecting out of the heart to supply the rest of the body. So a lot of our management is directed towards relieving this obstruction.

Host: And speaking of management, you led me beautifully into my next question before we get to treatment options, how about the management options here?

Robby Wu, DO, FACC: So there are several management and treatment options for HCM now, and first of all, we always encourage patients to stay really well hydrated and drink lots of water, because that alone sometimes can help with obstruction and symptoms. Traditionally, we've used medications called beta blockers and calcium channel blockers to treat this disease.

And these relax the heart and allow for better filling and blood flow. There's a new class of medications called cardiac myosin inhibitors that we've been recently using, and they've been really effective in helping to manage symptoms of obstruction. As I mentioned, we've been prescribing these medications a lot at TGH now, and they've been extremely effective.

But they are a little on the newer side. Then if patients continue to have symptoms despite medical therapy, there are some procedural options as well too. So things like alcohol septal ablation, open heart surgical myectomy. As you can imagine, these are more last resort options. But they do, sometimes really help patients feel a lot better.

Very, very rarely, patients will go on to need a heart transplant because of HCM. But that's really less than 5% of all patients with HCM that will require a heart transplant.

Host: Gotcha. Now, as for treatment, So who treats HCM?

Robby Wu, DO, FACC: In general, most cardiologists treat HCM, but because of the complexities of the disease and all the things that we just talked about, the American College of Cardiology and the American Heart Association do recommend that patients with HCM seek expert care in a multidisciplinary HCM Center of Excellence.

And this has been really shown to improve outcomes and lead to better care. I'm really happy to announce that our HCM program at TGH and USF has recently been recognized as an HCMA Center of Excellence. We're the only medical center on the west coast of Florida to achieve this designation, and we're really proud of that.

We have a really great multidisciplinary team. We're really patient focused and we're able to take care of the whole spectrum of the disease process. We do work together with cardiologists from all over the state of Florida. We really take pride in offering the highest levels of care to our patients with HCM.

Host: Well, congratulations on that great designation, right?

Robby Wu, DO, FACC: Thank you very much.

Host: Absolutely. And finally, in summary here, Doc, where can patients go for more information on all this?

Robby Wu, DO, FACC: Yeah. So if you Google, TGH HCM, one of the first links that pops up is our HCM program at the TGH and USF Heart and Vascular Institute. That's got a lot of good information about the disease, our team, and even how to get a referral if you need one. Another website I always recommend to patients is the HCMA website.

The HCM Association is a really great patient advocacy group. It's an international resource for patients, families, and the whole medical community really for HCM. Their website is the number four, so 4hcm.org. And there's lot of good patient-centric information on that website.

Host: So four, as the doctor mentioned, the number 4hcm.org. And certainly a great resource available there. Well, folks, we trust you are now more familiar with hypertrophic cardiomyopathy. Dr. Wu, valuable information indeed. Keep up all your great work and thanks so much again.

Robby Wu, DO, FACC: Thanks so much for having me.

Host: Absolutely. For more information folks, please visit tgh.org/heart.

If you enjoyed this episode, please be sure to like, subscribe, and follow Community Connect presented by TGH on your favorite podcast platform. I'm Joey Wahler. Thanks again for being part of Community Connect presented by Tampa General Hospital.