DETERMINANTS OF SUCCESS OF CORONARY ANGIOPLASTY IN PATIENTS WITH A CHRONIC TOTAL OCCLUSION - A MULTIPLE LOGISTIC-REGRESSION MODEL TO IMPROVE SELECTION OF PATIENTS

Objective-To study the determinants of success of coronary angioplasty in patients with chronic total occlusions, and to formulate a multipl e logistic regression model to improve selection of patients. Design-A retrospective analysis of clinical and angiographic data on a consecu tive series of patients. Patients-312 patients (mean age 55, range 31 to 79 years, 86% men) who underwent coronary angioplasty procedure for a chronic total occlusion between 1981 and 1992. Results-Procedural s uccess was achieved in 191 lesions (61.2%). A major complication occur red in six patients (1.9%). Multiple stepwise logistic regression anal ysis identified the presence of bridging collaterals (p < 0.001), the absence of a tapered entry configuration (p < 0.001), estimated durati on of occlusion of greater than three months (p = 0.001), and a vessel diameter of less than 3 mm (p = 0.003) as independent predictors of p rocedural failure. The logistic regression model was used to classify patients into groups of high, intermediate, and low probability of pro cedural success with cut off points of 70% and 30%. The predictive val ue for procedural success (probability greater-than-or-equal-to 70%) w as 91% (95% confidence intervals (95% CI) 83% to 96%) and predictive v alue for procedural failure (probability <30%) was 81% (95% CI 64% to 92%). Conclusions-Percutaneous transluminal coronary angioplasty of ch ronic total occlusions is associated with a low risk of acute complica tion. Procedural success is influenced by easily identifiable clinical and angiographic features and the multiple regression model described may help to improve selection of patients.