The transstenotic pressure gradient trend as a predictor of acute complications after percutaneous transluminal coronary angioplasty

Abstract

The transstenotic pressure gradient recorded during coronary angioplasty (PTCA) reflects the dynamic relationship that exists between coronary blood flow and the effective cross-sectional area of the arterial lumen. An apparent relationship between the dynamic behavior of the pressure gradient and subsequent acute vessels closure was observed in our catheterization laboratory. We therefore examined the usefulness of the pressure gradient trend in predicting acute complications after 463 attempted PTCA procedures. Two pressure gradient trend patterns were identified: (1) a rising trend pattern identified by an increasing pressure gradient in the interval after deflation of the angioplasty, and (2) a stable trend pattern identified by a constant or decreasing pressure gradient. The incidence of acute vessel closure (17% vs 4%, p = .0001), emergency CABG (5.6% versus 1%, p < .05), and myocardial infarction (13% versus 2%, p < .0001) after the PTCA procedure was significantly higher among patients with rising trend patterns when compared with patients with stable trend patterns. Multivariate analysis identified independent predictors for an acute closure event as a rising trend pattern (p < .001), post-PTCA gradient (p < .05), and post-PTCA percent diameter stenosis (p < .02). Independent predictors for emergency coronary artery bypass grafting and myocadial infarction were post-PTCA gradient (p < .001) and a rising trend pattern (odds ratio = 2.91, p < .001), respectively. The dynamic behavior of the gradient trend provides additional useful information about the results of dilatation. This information is available beofre completion of dilatation and may assist in clinical decision making by identifying those patients who may be at risk for developing acute complications in the post-PTCA period.