[Disturbances of myocardial perfusion by exertion scintigraphy in patients with hypertrophic cardiomyopathy and their relationship with sudden death risk factors].
Heart muscle perfusion was studied by exertion scintigraphy Tal-201 in 24 patients, 16M and 8F, aged 16-45 years, means--28 +/- 7.4 years with hypertrophic cardiomyopathy. The relationship between perfusion disturbances and sudden death risk factors occurring in this group of patients was evaluated. Disturbances of heart muscle perfusion were found in 20 pts (83%); 2 pts had permanent perfusion defects, in 18 pts these defects were completely or partially reversible at rest. Only 4 pts (17%) had normal heart muscle perfusion. In patients with perfusion disturbances there was found a significantly more frequent occurrence of the following sudden death risk factors: 1. syncope (p less than .01) 2. ventricular arrhythmia of IV b class according to Lown (p less than .01) 3. advanced hypertrophy of intraventricular septum (p less than .01) 4. sudden death in patients families (p less than .05) The evaluation of the heart muscle perfusion confirmed the occurrence of myocardial ischemia in most of the examined patients. Normal coronaro-angiography in all the patients over 35 years as well as the young age of the other patients exclude atherosclerosis as the cause of myocardiac ischemia in the group under study. This is a confirmation of nonatherosclerotic etiology of myocardiac ischemia in hypertrophic cardiomyopathy patients. The correlation between perfusion disturbances and sudden death risk factors points to the role of ischemia in the natural course of disease and the value of exertion scintigraphy TI-201 in prognosing patients with hypertrophic cardiomyopathy.