Influence of continued smoking and some biological risk factors on restenosis after percutaneous transluminal coronary angioplasty

Objectives. To identify possible biological risk factors for restenosis 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 prospective smoking controlled study all subjects had a routine angiographic restudy after 6 months. The biological risk factors assessed before angioplasty were adrenaline, endothelin, fibrinogen, lipoprotein (a) and tissue plasminogen activator.
Subjects. The study population consisted of 122 patients of whom 25% were current smokers.
Main outcome measures. Angiographic restenosis was defined as at least 50% diameter stenosis on the follow-up angiogram after an initially successful procedure.
Results. Restenosis was observed in 43% of patients. The restenosis rate was significantly lower among current smokers, but they were significantly younger and also had significantly less dilated stenoses. Multivariate analysis revealed the number of dilated stenoses, the mean inflation time, post-PTCA percentage diameter stenosis and left anterior descending coronary artery to be predictive of restenosis, while continued smoking was not. When only the lesion with the greatest loss in luminal diameter of each patient was considered, the multiple linear regression analysis revealed high endothelin level to be predictive of restenosis.
Conclusions. This study revealed high endothelin levels to be predictive of luminal narrowing after angioplasty. In addition, the number of dilated stenoses, the mean inflation time, post-PTCA percentage diameter stenosis and stenosis location in the left anterior descending artery were found to be predictive of restenosis. However, continued smoking after angioplasty did not emerge as a risk factor for restenosis.