Relationship Between Exercise-Induced Myocardial Ischemia and Reduced Left Ventricular Distensibility in Patients with

Many studies have demonstrated that reduced left ventricular (LV) diastolic distensibility plays a key role in the pathophysiol-ogy of hypertrophic cardiomyopathy (HCM). However, the rela-tionship between myocardial ischemia and reduced LV disten-sibility in HCM remains unclear. We aimed to clarify the relationship between exercise-induced ischemia and reduced LV distensibility in patients with HCM. Methods: Twenty pa-tients with HCM and 5 age-matched control subjects underwent stress-redistribution 201Tl myocardial scintigraphy and biven-tricular cardiac catheterization and echocardiography at rest and during exercise. Scintigraphic defect analysis was inter-preted using Berman’s 20-segment model. The summed stress score (SSS) was calculated as the sum of scores of the 20 LV segments and the summed difference score (SDS) was calcu-lated as the sum of differences between each of the 20 L