CLINICAL, ANGIOGRAPHIC, AND PROCEDURAL DETERMINANTS OF MAJOR AND MINOR CORONARY DISSECTION DURING ANGIOPLASTY

Angiographic evidence of coronary dissection after angioplasty is foun d in 25% to 30% of cases. Although patients are usually asymptomatic, in a small percentage angioplasty-induced coronary dissection results in luminal impairment and ischemic complications. The present study wa s undertaken to identify factors responsible for a predisposition to c oronary dissection after angioplasty and to determine whether major an d minor dissections share the same underlying risk factors. Clinical r ecords and angiograms from 363 patients with 489 lesions were retrospe ctively graded for the presence and severity of dissection and complic ations. Both major and minor angiographic dissections were noted in 30 .3%, and in 8.8% they were major. On multivariate analysis the most si gnificant correlates of any dissection included a balloon-to-artery ra tio >1.1 (p = 0.0001), calcification (p = 0.003), presence of other le sions in the angioplasty vessel (p = 0.018), and lesion length (p = 0. 02). However, in a multivariate model there were no variables that cou ld predict whether a dissection would be major or minor. Only the mean total number of inflations was significantly different, but this was likely the result rather than the cause of dissection. Thus a number o f variables can predict the occurrence of angiographic coronary dissec tion after angioplasty. Major dissections constitute a small fraction of the total number but are difficult to predict differentially.