Investigators from the SWEDEHEART nationwide observational study aimed to analyze the outcomes of patients with unprotected left main coronary artery (LMCA) disease who underwent either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI). The study included 11,137 patients registered in the Swedish national registry between January 2005 and December 2015. Excluded were patients with previous CABG, ST-elevation myocardial infarction (MI), or cardiac shock. The study assessed the occurrence of death, MI, stroke, and new revascularization during follow-up until December 2015, using national registries.
The results showed that patients undergoing PCI were older and had a higher prevalence of comorbidity but a lower prevalence of three-vessel disease compared to those who underwent CABG. After adjusting for known confounders with inverse probability weighting (IPW) analysis, PCI patients had higher mortality compared to CABG patients, with a hazard ratio of 2.0. Adjusting for known and unknown confounders using instrumental variable (IV) analysis also demonstrated higher mortality for PCI patients, with a hazard ratio of 1.5. Moreover, PCI was associated with a higher incidence of major adverse cardiovascular and cerebrovascular events (MACCE) than CABG, with an IV analysis hazard ratio of 2.8. Interestingly, diabetic patients showed a significant quantitative interaction, indicating that CABG provided longer median survival time compared to PCI in patients with diabetes.
In conclusion, this non-randomized study suggests that CABG in patients with LMCA disease is associated with lower mortality and fewer MACCE compared to PCI, even after adjusting for various confounding factors. The findings highlight the potential benefits of CABG as a preferred treatment option for patients with LMCA disease, particularly in terms of long-term survival. However, it’s important to note that this study has limitations inherent to its observational design, and further research, including randomized controlled trials, is needed to validate these findings and guide clinical decision-making.
Original article: Persson J et al. Eur Heart J. 2023 Jun 8.