Angiographic features associated with acute coronary artery occlusion during elective angioplasty

To examine the morphologic features of stenotic segments developing abrupt coronary occlusion during elective angioplasty, 36 cases occurring at the Toronto General Hospital between January 1985 and December 1989 were evaluated and compared with a temporally matched successful group. Quantitative arteriographic analysis was performed, including estimates of arterial tortuosity (proximal-stenotic axis deviation) and qualitative assessment for dystrophic calcification, residual lumen eccentricity and intimal irregularity. Acute occlusion occurred more frequently in the mid-arterial segment (success, mid 14 versus occlusion 21, P less than 0.05). Stenosis severity assessed by minimum stenotic diameter did not affect outcome (success 0.42 mm versus occlusion 0.37 mm, not significant or relative percentage diameter stenosis (success 86% versus occlusion 86%, not significant). Average stenotic length was equal (success 14.3 mm versus occlusion 13.6 mm, not significant), although coronary arterial tortuosity was increased in the acute occlusion group (success 27 degrees versus occlusion 34 degrees, P less than 0.05). Residual lumen eccentricity score was increased (success 1.66 versus occlusion 2.69, P less than 0.001), with greater dystrophic calcification in the occlusion group (success 0.31 versus occlusion 0.69, P less than 0.05). In addition, intimal irregularity was significantly greater (success 1.65 versus occlusion 2.5, P less than 0.001), although major arterial side branches failed to predict outcome (success 28% versus occlusion 36%, not significant). These data suggested that a mid-coronary anatomic location, arterial tortuosity, lumen eccentricity, dystrophic calcification and intimal irregularity increased the probability of acute occlusion during elective coronary angioplasty.