Procedures of nuclear cardiology are applied to the diagnosis and follow-up of hypertrophic cardiomyopathy in two aspects: (a) in the determination of myocardial thickening and (b) to document functional response to therapy. For morphological studies, T1-201 myocardial scintigraphy was introduced by Bulkeley in 1975 (7). Using a gated SPECT technique for myocardial scintigraphy, the wall thickening in different myocardial regions could be recorded (25). Soon after their introduction, gated blood pool studies were utilized to image regional dimension and motion of the myocardial wall (17). Later, instead of gated blood pool studies, one and two dimensional echocardiography were employed (8, 16). Besides morphological parameters, regional functional data at rest are available which enable one to quantify regional disorders and responses to drugs (6, 9, 21, 24). Nuclear cardiological measurements of global left ventricular functions, based on analysis of the left ventricular volume curve (time activity curve), were introduced by Bonow (3) in patients with hypertrophic cardiomyopathy before and during verapamil treatment.