What Do Patients With Hypertrophic Cardiomyopathy Die from?

Hypertrophic cardiomyopathy (HC) has become a contemporary and treatable genetic heart disease, now with disease-related mortality reduced to as low as 0.5% per year, based largely on more effective risk stratification and the use of the implantable cardioverter-defibrillator for primary prevention of sudden death. This paradigm change in the natural history of HC has caused us to reconsider the overall mortality risk in this disease. We interrogated the databases of 2 HC referral centers, Minneapolis Heart Institute and Tufts Medical Center. Of 1,902 consecutive patients evaluated between 1992 and 2013, 1,653 patients (87%) have survived to the end of follow-up and 249 patients (13%) have died. Most deaths (178 of 249; 72%) were unrelated to HC, commonly because of cancer and predominantly in older patients. Non-HC mortality was significantly more common in adults presenting ≥ 60 years and least common in the youngest patients aged <30 years (p <0.001). Notably, deaths from non-HC causes substantially exceeded HC-related causes by 2.6-fold (p <0.001). In conclusion, only about 25% of patients with HC ultimately died of their disease, including predominantly those who were <30 years of age. These data allow patients with HC to develop a more realistic and reassured perception of their disease.