Hypertrophic nonobstructive cardiomyopathy with giant negative T waves (apical hypertrophy): Ventriculographic and echocardiographic features in 30 patients

Abstract

In 30 of 1,002 consecutive patients who had left heart catheterization and cineangiography for evaluation of either ischemic heart disease or cardiomyopathy the electrocardiogram showed giant negative T waves (greater than 10 mm) associated with high QRS voltage (R wave greater than 26 mm in lead V5 or the sum of the S wave in lead V1 and the R wave in lead V5 35 mm or more) in the precordial leads despite absence of hypertension or significant coronary artery disease. In all 30 patients a characteristic spade-like configuration (concentric apical hypertrophy) was observed in the right anterior oblique ventriculogram at end-diastole as well as in the long axis two dimensional echocardiogram. The average apical thickness in these patients (24.8 ± 6.6 mm) was significantly greater than that in normal subjects (9.4 ± 3.1 mm) (P < 0.001) or in patients with hypertrophic obstructive cardiomyopathy (14.7 ± 5.0 mm) (P < 0.001). Values for both the mid anterior free wall thickness (13.9 ± 4.1 mm) and the mid posterior free wall thickness (14.3 ± 3.0 mm) were greater than values in normal subjects (8.9 ± 1.8 mm and 8.2 ± 2.0 mm, respectively) (P < 0.001). However, the ratio between the apical and the mid anterior free wall thickness in these 30 patients (1.86 ± 0.53) was significantly greater than the ratio in normal subjects (1.05 ± 0.24), patients with hypertrophic obstructive cardiomyopathy (0.96 ± 0.15) (P < 0.001) and patients with types of nonobstructive hypertrophic cardiomyopathy (1.26 ± 0.24) (P < 0.005) other than apical concentric hypertrophy. Obstruction of the tract did not occur because the upper half of the septem remained rather thin in systole and did not bulge into the left ventricle during systole. Pressure study with proper provocations as well as two dimensional echocardiograms revealed no peak systolic pressure gradient or obstruction within the outflow tract of the left ventricle. It is concluded that these 30 patients have nonobstructive hypertrophic cardiomyopathy with marked concentric hypertrophy in the apex (apical hypertrophic type) and with a different septal shape and contraction pattern from those seen in the obstructive type. This type of hypertrophy appears to be a fairly common type of hypertrophic cardiomyopathy in Japan.