[Influence of the severity of coronary stenosis on the course of left ventricular function in case of subsequent coronary occlusion. Longitudinal coronarographic study].

In order to evaluate the consequences concerning left ventricular function of the spontaneous occlusion of coronary stenoses, the authors studied the clinical and angiographic characteristics of 30 consecutive patients (25 men, 5 women, mean age: 54) undergoing successive coronary arteriograms showing progression to complete occlusion of the anterior interventricular or right coronary between the two investigations. Two groups of patients were identified: Group I (n = 19) with occlusion of a previously moderate (< or = 50%) stenosis; Group II (n = 11) with occlusion of an initially tight stenosis (> 50%). At the time of the first angiogram, left ventricular ejection fraction (LVEF) was 60 +/- 13% in Group I and 58 +/- 9% in Group II (NS). Times between the two investigations were similar in the two groups (58 +/- 43 months and 54 +/- 57 months, NS). Between the two coronary arteriograms, 7 patients of Group I sustained an infarction as against 3 in Group II (NS). Impairment of LVEF developed in 16 patients of Group I (84%) as against 5 of Group II (45%) (p < 0.005). Global LVEF varied on average by -10.4 +/- 13.3% (p < 0.005) in Group I and -0.1 +/- 9.5% (NS) in Group II. This difference in variation in LVEF between the two groups was significant (p < 0.04). Spontaneous occlusion of moderate coronary stenoses results in certain cases in greater impairment of left ventricular function than the occlusion of tight stenoses. The development of a collateral circulation probably plays a protective role in the second group.