Objectives-To assess the influence of smoking on restenosis after coronary angioplasty. Design and patients-The incidence of smoking on restenosis was investigated in 2948 patients. They were prospectively enrolled in four major restenosis trials in which quantitative angiography was used before and immediately after successful angioplasty and again at six months. Results-Within the study population there were 530 current smokers, 1690 ex-smokers, and 728 non-smokers. Smokers were more likely to be men (85.9% v 87.5% v 65.3%, current v exv non-, p < 0.001), to be younger (54.0 (9.0) v 57.0 (9.1) v 59.9 (9.4) years, p < 0.001), to have peripheral vascular disease (7.2% v 5.5% v 2.3%, p < 0.001), and have sustained a previous myocardial infarction (42.9% v 43.9% v 37.9%, p = 0.022), but were less likely to be diabetic (9.1% v 9.5% v 12.6%, p = 0.043) or hypertensive (24.9% v 29.3% v 37.2, p < 0.001). There was no significant diVerence in the categorical restenosis rate (> 50% diameter stenosis) at six months (35.28% v 35.33% v 37.09%, current v ex-v non-), or the absolute loss (0.29 (0.54) v 0.33 (0.52) v 0.35 (0.55) mm, respectively; p = 0.172). Conclusions-Although smokers have a lower incidence of known predisposing risk factors for atherosclerosis, they require coronary intervention almost six years earlier than non-smokers and three years earlier than ex-smokers. Once they undergo successful coronary angioplasty, there appears to be no evidence that smoking influences their short term (six month) outcome, but because of the known long term eVects of smoking, patients should still be encouraged to discontinue the habit. (Heart 2000;84:299-306)

Complex morphological changes induced by intervention may contribute to discordance between the two quantitative imaging techniques. In the absence of ICUS, VID may be a complementary technique to ED in lesions with complex morphology after balloon angioplasty and directional atherectomy.

These results indicate that successfully dilated coronary occlusions, both total and functional, have a higher rate of angiographic restenosis at 6 months than stenoses. This is due chiefly to a higher rate of occlusion at follow-up angiography in this group of lesions. Measures aimed at reducing restenosis after successful dilatation of coronary occlusion should be focused in this direction.