Smoking Cessation as an Effective Component of Secondary Prevention in Patients at Very High Cardiovascular Risk After Acute Coronary Syndrome

INTRODUCTION: The study aims to assess clinical, laboratory, and instrumental outcomes depending on smoking status in patients undergoing Cardiac Rehabilitation (CR) after Acute Coronary Syndrome (ACS). METHODS: The prospective cohort study involved 124 post-ACS patients (aged 28-77 years; Me = 57, IQR: 48-64). Data collection occurred at three stages: during inpatient CR, after 3-6 months, and one year post-ACS. Patients underwent clinical evaluation, smoking status assessment, laboratory tests (complete blood count, lipid profile, PCSK9 levels), and instrumental studies (echocardiography, bicycle ergometry, coronary angiography). RESULTS: The proportion of smokers decreased by 47.6 ± 10.8% after one year of CR. Smoking patients had significantly higher ESV values [70.0 (61.2,84.0) mL] than non-smokers [52.5 (45.3,61.3) mL] (p = .003). Patients who quit smoking showed no significant difference in ESV or ESVI compared to non-smokers at 3-6 months, suggesting stabilization of remodeling. Nonsmokers and quitters had favorable lipid dynamics: PCSK9 levels decreased after physical exertion (512.0 to 467.5 ng/mL; p = .001) and remained lower throughout the year (p = .036). At one year, total cholesterol was lower in quitters, 3.80 (3.35,4.10) mmol/L, than in smokers, 4.60 (3.73,5.68) mmol/L, p = .03; LDL-C was also lower in quitters, 2.07 (1.55,2.73) mmol/L vs. smokers, 2.71 (2.13,3.96) mmol/L, p = .02. DISCUSSION: These findings may suggest that smoking status could influence recovery patterns after ACS during СR. CONCLUSION: In this observational cohort, both smoking cessation during cardiac rehabilitation and the absence of smoking tended to be associated with more favorable echocardiographic parameters and lipid profile, including lower levels of total cholesterol, LDL-C, and PCSK9, in patients after ACS.