Aims: To study the impact of smoking on the change in exercise capacity in patients treated with coronary angioplasty.
Methods: Three hundred and sixty-eight men below 70 years of age eligible for percutaneous transluminal coronary angioplasty without previous coronary interventions were consecutively enrolled. Of the 334 patients (90.8%) who completed the study 77 (23.1%) were current smokers. Exercise tests were performed before percutaneous transluminal coronary angioplasty, 2 and 19 +/- 2.4 weeks after percutaneous transluminal coronary angioplasty. Coronary angiography was done in 333 patients (99.7%) (at mean 19 +/- 2.4 weeks). The angiograms were analysed quantitatively.
Results: There were no differences in the clinical and angiographic characteristics among the groups except for age. The non-smokers were older than the smokers (55.7 vs 52.4 years (P = 0.001)). Exercise capacity was equal before percutaneous transluminal coronary angioplasty in both groups (17.6 vs 16.5 W x min-1 x kg-1). Non-smokers had a significantly higher increase in exercise capacity than smokers from baseline to 2 weeks after percutaneous transluminal coronary angioplasty (mean difference 4.3 W x min-1 x kg-1 (95% CI: 2.3 to 6.2; P < 0.001)), and from baseline to 19 weeks after percutaneous transluminal coronary angioplasty (mean difference 3.9 W x min-1 x kg-1 (95% CI: 1.6 to 6.2; P < 0.001).
Conclusion: A clinical benefit from percutaneous transluminal coronary angioplasty was seen in both groups as judged from exercise testing. Smokers had a substantially lower increase in exercise capacity than non-smokers, indicating an attenuated benefit from percutaneous transluminal coronary angioplasty among smokers.