Intraventricular conduction disturbances and coronary artery disease: Clinical, hemodynamic and angiographic study

Abstract

The clinical, hemodynamic and angiographic findings of 42 patients with coronary artery disease and electrocardiographic and vectorcardiographic evidence of an intraventricular conduction disturbance are reported. All patients were evaluated because of symptomatic heart disease, and they represent 7 percent of patients with coronary artery disease studied. Right bundle branch block was present in 6, left anterior hemiblock in 18, left anterior hemiblock with right bundle branch block in 9 and left bundle branch block in 8 patients; only 1 patient had right bundle branch block with left posterior hemiblock. Angina pectoris was present in 79 percent. Congestive heart failure and cardiomegaly were common in patients with left bundle branch block and left anterior hemiblock with right bundle branch block. Transmural myocardial infarction on electrocardiogram and vectorcardiogram was common (55 percent), involving the anterior wall of the left ventricle in 72 percent. Eight patients with left bundle branch block or left anterior hemiblock with right bundle branch block had a prolonged P–R interval. Patients with right bundle branch block had normal left ventricular function, end-diastolic volume and ejection fraction, and predominant three vessel coronary disease. In the absence of a transmural myocardial infarction, left anterior hemiblock was associated with normal end-diastolic volume and ejection fraction. More than half of the patients with left anterior hemiblock had single vessel disease. Patients with left bundle branch block or right bundle branch block with left anterior hemiblock had almost uniformly abnormal left ventricular hemodynamics, end-diastolic volume and ejection fraction, and the majority had double or triple vessel disease. The single patient with left posterior hemiblock and right bundle branch block had normal left ventricular function. All the patients with abnormal left ventricular function had abnormal anterior or apical systolic wall abnormalities, or both. All the patients, except the one with left posterior hemiblock and right bundle branch block, had significant disease of the left anterior descending coronary artery. We conclude that the hemodynamic derangements found are correlated more with the intraventricular conduction disturbance than with the extent of the coronary artery disease. The only significant relation with coronary artery disease was the finding of major disease of the left anterior descending coronary artery in all but one patient.