[Are the spontaneous coronary recanalization and the coronary collateral circulation really important in the left ventricular preservation in acute myocardial infarct?].

PURPOSE: To determine if maintenance of residual blood flow to culprit coronary artery in acute myocardial infarction is important in preserving left ventricular systolic function.

METHODS: Prospective study of 63 consecutive survivors of acute myocardial infarction in the prethrombolytic era that were submitted to cinecoronary angiography and 30 degrees RAO left ventriculography on the 4th week. Culprit coronary artery patency and collateral circulation were correlated with global and segmental left ventricular contractility.

RESULTS: Spontaneous coronary recanalization correlated significantly with better left ventricular systolic function only in patients with anterior wall myocardial infarction. This relationship was stronger with segmental than with global contractility. Besides, it was seen that absence of recanalization of pre-septal left anterior descending coronary artery occlusion resulted in significantly worse global and segmental left ventricular systolic function than post-septal occlusion, resulting in left ventricular aneurysm in all patients (2/3 of recanalized patients versus 1/3 of post-septal occlusions). Collateral circulation to culprit coronary artery correlated significantly with better global and segmental left ventricular contractility only in patients with inferior wall myocardial infarction.

CONCLUSION: In acute anterior wall myocardial infarction spontaneous coronary artery recanalization is associated with better global and segmental left ventricular systolic function, specially if the occlusion is of pre-septal localization, while collateral circulation is not related to better contractility. In acute inferior wall myocardial infarction one sees the reverse.