RESUMO
The purpose of this study was to define the spectrum of left ventriculographic (LV) abnormalities in 60 patients with isolated Greater Than or Equal To 90% diameter narrowing of the left anterior descending artery (LAD). The patients were divided into three groups: Group I (26 patients) had normal left ventricular (LV) function with ejection fraction (EF) of Greater Than 60% and no akinetic-dyskinetic segment representing abnormal contracting segments (ACS) of the left ventricular wall; Group II (15 patients) had mild to moderate LV dysfunction with EF of 40-60% and an akinetic-dyskinetic segment of Less Than 30% of the end diastolic perimeter (0-30%; mean, 11.6%) and Group III (19 patients) had severe LV dysfunction with EF Less Than 40%, or an akinetic-dyskinetic segment of Greater Than or Equal To 30% (30-81%; mean, 41.5%) or both. The data obtained from the history, physical examination, electrocardiogram (ECG), chest x-ray studies, hemodynamic studies, left ventriculography, and coronary arteriography were entered and filed on a memory disc in an IBM 370-168 computer. Analysis of the results showed: 1) more severe LV dysfunction is associated with increased incidence of large hearts, gallops, decreased cardiac output, and occlusion of the LAD. 2) ECG evidence of infarction is also associated with higher incidence of the abnormalities of the indices of LV dysfunction. 3) LAD occlusion (versus stenosis) has a higher incidence of severe LV dysfunction and prior infarction. 4) The site of LAD disease did not predict the extent of left ventricular dysfunction. 5) Collaterals did not protect against severe LV dysfunction.