Preservation of left ventricular function in patients with total occlusion of the left anterior descending coronary artery and wide‐caliber distal vessel filling by collateral vasculature

The segmental ventricular function of 76 patients with total occlusion of the left anterior descending coronary artery (LAD) was analyzed to establish the relationship between ventricular function and the presence and angiographic appearance of the collateral circulation. The relationship between function and collateral supply was found to be significant (P less than .01). The only angiographic feature of the collateral vasculature that was associated with preserved function was the caliber of the distal LAD. Wide-caliber vessels were more likely to be associated with preserved ventricular function than thin vessels (P less than .01). In contrast, both rapidly filling collateral arteries and slow filling vessels were associated with preserved ventricular function. Collateral supply maintenance was significantly associated with preserved ventricular function, even when the collaterals arose from stenotic coronary arteries. Furthermore, despite marked differences in ventricular function between the base and apex of the heart, there was a true relationship between preserved ventricular function and the presence of collateral vessels for all segments of the anterior wall. These findings may be relevant to clinical decision making and to proper interpretation of studies of ventricular function following LAD occlusion.