Disappearance of giant negative T waves in patients with the Japanese form of apical hypertrophy.

Abstract

The present study investigated the long-term changes in the electrocardiographic (ECG) hallmarks of the Japanese form of apical hypertrophy. Giant negative T waves and tall R waves in the left precordial leads are the ECG hallmarks of the Japanese form of apical hypertrophy. However, the long-term course is largely unknown. Twenty-nine patients with apical hypertrophy (26 men, 3 women, mean age +/- SD 50.4 +/- 8.2 years) who showed left precordial giant negative T waves (< or = -10 mm) and tall R waves (> or = 26 mm) and spade configuration in the left ventriculogram were followed up for 10.9 +/- 3.7 years. The intermediate follow-up ECGs (5 to 9 years) showed disappearance of giant negative T waves in 31% and of tall R waves in lead V5 in 6%. At the long-term follow-up study (> or = 10 years), loss of giant negative T waves increased to 71%, with average T wave negativity in lead V4 or V5 decreasing from -16.5 +/- 5.1 to -6.9 +/- 4.2 mm. These T wave changes were associated with decreases in R wave amplitude in lead V5 from 40.7 +/- 9.6 to 26.1 +/- 13.8 mm, with loss of tall R waves in lead V5 in 38% of patients and development of abnormal Q waves in two patients. During the long-term follow-up of the Japanese form of apical hypertrophy, giant negative T waves disappeared in association with decreases in R wave amplitude in lead V5, indicating that these ECG hallmarks are clinical features that evolve progressively during the natural course of the disease.