Holter system electrocardiographic studies on 617 cases.

Holter system electrocardiograms were recorded for 617 patients who were treated at the Department of Cardiology, Tokai University Hospital. In cases of arrhythmia, ventricular premature contraction (VPC) was the most predominant, in 291 cases (69%) out of 423 with arrhythmia, followed by 59 (14%) with supraventricular premature contraction (SVPC), 23 (5.4%) with paroxysmal atrial tachycardia, 17 (4%) with second degree A-V block and 10 (2.3%) with transient atrial fibrillation (AF). In addition, nine (2.1%) cases of ventricular tachycardia (VT), one (0.2%) of transient ventricular fibrillation (VF) and one (0.2%) of third degree A-V block were found in particularly severe arrhythmia cases. Six out of nine cases of VT were cases of acute myocardial infarction (AMI) and all died suddenly while in the hospital or after discharge. Mild or moderate changes in ST-T were often observed even in normal subjects. Of the 617 cases, only 18 (2.9%) showed a significant elevation or depression of ST. Among these, three definitely had variant angina pectoris (Prinzmetal type). The above results indicate Holter EKGs are very useful for the diagnosis of arrhythmia and can also be used as a means of evaluating the prognosis in some cases, but there still are some problems in connection with its use for the diagnosis of ischemic heart disease except for the diagnosis of variant angina pectoris.