Despite the increasing popularity of electronic cigarettes (E-cigarettes), the prognostic impact of switching to E-cigarettes in smokers with coronary artery disease (CAD) who underwent percutaneous coronary intervention (PCI) remains uncertain.

Recently, several studies have reported that, although lower than combustible cigarette users, E-cigarette users had a significantly higher risk of future myocardial infarction (MI) or cardiovascular disease compared with non-smokers or quitters. However, because all previous studies has focused on the general healthy population, these results cannot be extrapolated for patients who already proven atherosclerotic cardiovascular disease (ASCVD), such as undergoing percutaneous coronary intervention (PCI) for coronary artery disease (CAD). Although Busch et al. previously reported that a significant minority of patients are using E-cigarettes post-acute coronary syndrome smokers, a paucity of data exists regarding the impact of such transitions on clinical outcomes in current smoker patients with CAD who have undergone PCI. In light of these considerations, the current study sought to address this gap in knowledge by evaluating the prognostic implications of smoking habit changes, including E-cigarette use, among CAD patients with current smoking status following PCI.

Inclusion Criteria:

• patients who underwent health screening 3 years before and after the PCI

Exclusion Criteria:

• history of cancer
• history of ischemic stroke
• died within the first 3 months of follow-up from the index date
• Newly developed acute MI or received additional PCI or CABG from the index PCI date to the study index date

patients with coronary artery disease who underwent health screening 3 years before and after the PCI