INFLUENCE OF CONTINUED SMOKING AND SOME BIOLOGICAL RISK-FACTORS ON RESTENOSIS AFTER PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY

Objectives. To identify possible biological risk factors for restenosi s following successful percutaneous transluminal coronary angioplasty (PTCA) in patients having single or multivessel disease. The effect of continued smoking on restenosis was also evaluated. Design. In this p rospective smoking controlled study all subjects had a routine angiogr aphic restudy after 6 months. The biological risk factors assessed bef ore angioplasty were adrenaline, endothelin, fibrinogen, lipoprotein ( a) and tissue plasminogen activator. Subjects. The study population co nsisted of 122 patients of whom 25% were current smokers. Main outcome measures. Angiographic restenosis was defined as at least 50% diamete r stenosis on the follow-up angiogram after an initially successful pr ocedure. Results. Restenosis was observed in 43 % of patients. The res tenosis rate was significantly lower among current smokers, but they w ere significantly younger and also had significantly less dilated sten oses. Multivariate analysis revealed the number of dilated stenoses, t he mean inflation time, post-PTCA percentage diameter stenosis and lef t anterior descending coronary artery to be predictive of restenosis, while continued smoking was not. When only the lesion with the greates t loss in luminal diameter of each patient was considered, the multipl e linear regression analysis revealed high endothelin level to be pred ictive of restenosis. Conclusions. This study revealed high endothelin levels to be predictive of luminal narrowing after angioplasty. In ad dition, the number of dilated stenoses, the mean inflation time, post- PTCA percentage diameter stenosis and stenosis location in the left an terior descending artery were found to be predictive of restenosis. Ho wever, continued smoking after angioplasty did not emerge as a risk fa ctor for restenosis.