[Ventricular arrhythmias in left coronary main branch stensosis].

It is far from clear whether ischemia plays a major role in the genesis of ventricular arrhythmias in patients with chronic coronary heart disease. Since patients with left main coronary artery disease suffer from transient or even chronic ischemia including significant parts of the left ventricular muscle mass, it seems worthwhile looking for spontaneous arrhythmias in this particular clinical setting. Therefore we studied 56 patients (53 males, 3 females) with documented left main coronary artery disease (20 patients (35%) with 30-50% luminal narrowing, 36 patients (65%) with greater than or equal to 50% stenosis) using 24-hour continuous ambulatory electrocardiography. Only 5 patients were without ectopic activity. 32 patients (57%) showed ventricular extrasystoles (VES) of uniform or multiform configuration according to Lown class I-III, whereas 19 patients (34%) demonstrated consecutive VES equivalent to Lown class IV. In ten of the latter short runs of ventricular tachycardia (Lown IVb) were the maximal finding. No relation could be assessed between spontaneous ventricular arrhythmias and the extent of coronary artery disease, neither with regard to the degree of narrowing of the left main coronary artery, nor with regard to the additional coronary involvement in terms of 1-, 2- or 3-vessel disease. In contrast, there was a significant relationship between impaired left ventricular function in terms of biplane left ventricular ejection fraction and frequent VES (chi 2 = 11.272; p less than 0.01) as well as complex, namely consecutive forms (chi 2 = 9.548; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)