Impacts of smoking status on the clinical outcomes of coronary non-target lesions in patients with coronary heart disease: a single-center angiographic study.

Background: Coronary atherosclerotic plaque could go through rapid progression and induce adverse cardiac events. This study aimed to evaluate the impacts of smoking status on clinical outcomes of coronary non-target lesions.
Methods: Consecutive patients with coronary heart disease who underwent two serial coronary angiographies were included. All coronary non-target lesions were recorded at first coronary angiography and analyzed using quantitative coronary angiography at both procedures. Patients were grouped into non-smokers, quitters, and smokers according to their smoking status. Clinical outcomes including rapid lesion progression, lesion re-vascularization, and myocardial infarction were recorded at second coronary angiography. Multivariable Cox regression analysis was used to investigate the association between smoking status and clinical outcomes.
Results: A total of 1255 patients and 1670 lesions were included. Smokers were younger and more likely to be male compared with non-smokers. Increase in percent diameter stenosis was significantly lower (2.7 [0.6, 7.1] % vs. 3.5 [0.9, 8.9]%) and 3.4 [1.1, 7.7]%, P = 0.020) in quitters than those in smokers and non-smokers. Quitters tended to have a decreased incidence of rapid lesions progression (15.8% [76/482] vs. 21.6% [74/342] and 20.6% [89/431], P = 0.062), lesion re-vascularization (13.1% [63/482] vs. 15.5% [53/432] and 15.5% [67/431], P = 0.448), lesion-related myocardial infarction (0.8% [4/482] vs. 2.6% [9/342] and 1.4% [6/431], P = 0.110) and all-cause myocardial infarction (1.9% [9/482] vs. 4.1% [14/342] and 2.3% [10/431], P = 0.128) compared with smokers and non-smokers. In multivariable analysis, smoking status was not an independent predictor for rapid lesion progression, lesion re-vascularization, and lesion-related myocardial infarction except that a higher risk of all-cause myocardial infarction was observed in smokers than non-smokers (hazards ratio: 3.00, 95% confidence interval: 1.04-8.62, P = 0.042).
Conclusion: Smoking cessation mitigates the increase in percent diameter stenosis of coronary non-target lesions, meanwhile, smokers are associated with increased risk for all-cause myocardial infarction compared with non-smokers.