Smoking continuation and earlier relapse were more frequent among PCI patients than CABG patients after revascularization for acute coronary syndrome

Smoking cessation after acute coronary syndrome (ACS) and revascularization is a critical secondary prevention strategy. This study examined smoking behavior patterns and their associations with cardiovascular outcomes in patients who underwent percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) following ACS. This retrospective cohort study included 128 patients who were active smokers at the time of the index ACS event and subsequently underwent PCI (n = 74) or CABG (n = 54) between 2018 and 2022. Patients were followed for a mean of 36.4 ± 12.8 months. Smoking behavior, demographic characteristics, and cardiovascular events were assessed through medical records and structured interviews. The smoking continuation rate was 81.3% (104/128) and was significantly higher in the PCI group than in the CABG group (89.2% vs. 70.4%, p = 0.007). Among patients who continued smoking, time to relapse was shorter in the PCI group (2.8 ± 1.6 vs. 5.7 ± 2.4 months, p < 0.001), and post-relapse cigarette consumption was higher (15.3 ± 6.7 vs. 12.1 ± 5.9 cigarettes/day, p = 0.018). The composite cardiovascular outcome (33.3% vs. 13.2%, p = 0.024) and repeat revascularization (43.9% vs. 7.9%, p < 0.001) were more frequent in the PCI group. Recurrent ACS was numerically more frequent in the PCI group, but the difference was not statistically significant (28.8% vs. 13.2%, p = 0.068). Smoking continuation was frequent after ACS-related coronary revascularization, particularly among PCI patients, who also experienced earlier relapse. Less favorable cardiovascular outcomes were observed among PCI patients who continued smoking; however, these findings should be interpreted as exploratory associations because of the retrospective, non-randomized design and potential residual confounding. The results highlight the need for structured, sustained, and individualized smoking cessation and relapse-prevention support after coronary revascularization.