Advances in Treatment of Obstructive Hypertrophic Cardiomyopathy - Episode 4
John A. Spertus, MD, MPH, comments on the effect of oHCM on health status and quality of life for patients.
James Januzzi, MD: We’ve heard a lot about symptoms and how loud the symptoms may be in these individuals. John, you’re the world’s leading expert on health status in heart disease. You think about health status in general, and not just quality of life. I’m curious to hear your perspective as someone who thinks a lot about this with respect to the impact of HCM [hypertrophic cardiomyopathy] on health status in patients who are affected.
John A. Spertus, MD, MPH: I got interested in health status in large part taking a very patient-centered view of their disease. When patients come to us for help making a diagnosis and figuring out why they’re doing poorly and trying to get better, it’s often these symptoms that they’re seeking relief from. My thinking about this says it’s evolved over time, and the greater the symptoms, the more a mandate there is to come up with ways to treat them and try to address them. Conversely, the less the symptoms, the less aggressive we ought to be in treating. That applies to ischemic heart disease as well as hypertrophic obstructive cardiomyopathy.
I’ve been thinking more about how we start to identify, and I believe we aren’t as efficient in systematically measuring the impact of disease on patients, symptoms, function, and quality of life. It’s sometimes difficult to elicit that from patients because we’re busy. We don’t have time, or they’re hesitant to interrupt us. I’ve grown increasingly interested in the idea of formally measuring these. Doing this on a population health basis can be very important.
HCM is a little unusual in that patients, when the diagnosis is made, often will get referred to a cardiologist or advanced specialist, but a lot of times they aren’t. Having ways of systematically understanding the burden of disease from the patient’s perspective can be very helpful in accelerating their referral to experts like Steve and Martin, who can help us think through the best treatment options available.
James Januzzi, MD: That’s really useful. For the viewers, the Kansas City Cardiomyopathy Questionnaire [KCCQ], a tool that we use for assessing health status, is generally useful for that application in heart disease. John, can you give us a 10,000-foot view of what the KCCQ tells us in HCM and whether different domains in the questionnaire can inform different decisions?
John A. Spertus, MD, MPH: The KCCQ was developed for heart failure. As we’ve already heard, there are some important symptoms in HCM that differ a little from standard HFrEF [heart failure with reduced ejection fraction] and HFpEF [heart failure with preserved ejection fraction]. The baseline ischemia and chest pain isn’t specifically asked for. Exertional lightheadedness isn’t something that we ask in the KCCQ. The KCCQ was designed to ask the questions that an experienced heart failure specialist would ask of their patients at a routine clinical visit in the exact same way. How often are you having symptoms of fatigue and shortness of breath? How much does it bother you? How limited are you at doing activities because of your heart failure symptoms? How does that impact your quality of life or your social functioning?
We have been studying it quite a bit in the HCM population because first of all, patients with HCM don’t consider themselves to have heart failure. They consider themselves to have HCM. The Kansas City Cardiomyopathy Questionnaire asks about your heart failure, and it turns out that while patients don’t necessarily view their HCM as heart failure, they didn’t have much difficulty filling out the questionnaire.
I don’t want to be too technical, but we were very concerned about if something like the KCCQ is going to work well in HCM. Does it capture all the relevant domains that mean something to a patient with HCM? As I mentioned before, it doesn’t capture chest pain. It doesn’t capture exertional dyspnea or palpitations. We have recently done a lot of validation work in the HCM population and, as you’ve heard already, the predominant symptoms are fatigue, shortness of breath, and then less frequent but still common are chest pain, exertional lightheadedness, and palpitations.
It turns out that there was a specific instrument developed for that, the HCMSQ [Hypertrophic Cardiomyopathy Symptom Questionnaire]. It correlated well with what the KCCQ captured, in large part because—you probably would agree—it’s unusual for somebody to have chest pain or exertional lightheadedness or palpitations and not also have fatigue or shortness of breath. The KCCQ isn’t capturing those symptoms per se, but it’s capturing other important manifestations of the disease. It works well. There’s room to improve.
All of our assessments of patients’ health status are going to continually evolve, especially as we get new technologies and other approaches for understanding what our patients are feeling. The KCCQ is an interim solution to allow us to systematically understand how our patients are feeling from their own perspective and their own words, which opens up lots of advantages as a cardiologist to understand how my entire population of patients is doing and to speed up my clinic visit. Before I walk in the room, I can know how they’re doing. There are advantages, but there are some gaps that it doesn’t capture. But for the time being, it’s a good substitute, a good fill-in.
Martin S. Maron, MD: John, I have a question to ask you, too. Symptom burden is so important. We’re going to be talking more about that because that’s probably the predominant goal for treatment. We’re going to probably get to that in a minute. But given that symptom burden is so important, what we’ve been relying on in HCM for so long is the NYHA [New York Heart Association] class designation, which was taken from other forms of heart failure and applied to HCM because that’s how clinical cardiologists relate, through NYHA. I think what you’re saying is that these tools, which you’ve been a major part of developing, may give us a much more detailed assessment of symptom burden that goes beyond NYHA.
John A. Spertus, MD, MPH: Yes. I strongly believe that. The NYHA is very coarse and not exactly linear. The difference between III and IV is a lot smaller than II and III. But the biggest limitation of the New York Heart Association classification, in my mind, is that it’s the clinicians’ assessment of what the patient is telling them, and the exact same patient seeing 3 different clinicians will be called Class I by 1, Class II by another, and Class III by the third. That’s a real problem. Especially as cardiologists, with the degree of precision we want in phenotyping, cardiac anatomy, and physiology with echocardiography, strain, and MRI. We keep wanting finer tools, yet we’re happy with just the New York Heart Association classification for assessing symptoms. It drives me nuts because it’s internally inconsistent with what we otherwise want.
James Januzzi, MD: We make decisions about treatment on the basis of that poorly calibrated tool, which is an issue.
Transcript Edited for Clarity