Diagnosis and Evaluation of Hypertrophic Cardiomyopathy
Barry J. Maron, Milind Y. Desai, Rick A. Nishimura, Paolo Spirito, Harry Rakowski, Jeffrey A. Towbin, Ethan J. Rowin, Martin S. Maron, Mark V. Sherrid
Abstract
Hypertrophic cardiomyopathy (HCM) is a relatively common often inherited global heart disease, with complex phenotypic and genetic expression and natural history, affecting both genders and many races and cultures. Prevalence is 1:200-1:500, largely based on the disease phenotype with imaging, inferring that 750,000 Americans may be affected by HCM. However, cross-sectional data show that only a fraction are clinically diagnosed, suggesting under-recognition, with most clinicians exposed to small segments of the broad disease spectrum. Highly effective HCM management strategies have emerged, altering clinical course and substantially lowering mortality and morbidity rates. These advances underscore the importance of reliable HCM diagnosis with echocardiography and cardiac magnetic resonance. Family screening with noninvasive imaging will identify relatives with the HCM phenotype, while genetic analysis recognizes preclinical sarcomere gene carriers without left ventricular hypertrophy, but with the potential to transmit disease. Comprehensive initial patient evaluations are important for reliable diagnosis, accurate portrayal of HCM and family history, risk stratification, and distinguishing obstructive versus nonobstructive forms.