Treatment of left main coronary artery disease: an unresolved question

Atherosclerotic disease of the left main coronary artery (LMCA) is found in a considerable percentage of patients undergoing diagnostic coronary angiography. The optimal revascularization strategy for these lesions remains a topic of debate. Evidence over time has shown conflicting and opposing results regarding the best treatment approach for such patients. Among the most relevant studies to consider is the SYNTAX trial, which compared coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) and found no significant difference in mortality among patients with LMCA disease. Similar findings were reported in the EXCEL study, which included only patients with LMCA lesions, whereas the NOBLE study demonstrated superior outcomes with CABG in terms of cardiovascular events during follow-up. For this reason, we aimed to conduct an analysis of patients undergoing different revascularization strategies within our own setting.

The aim of this study was to describe the characteristics of the study population and the five-year survival of patients with LMCA disease treated with PCI or CABG.

A retrospective observational study was conducted, comparing a group of 213 patients treated for LMCA disease with a 5-year follow-up. Patients were divided into two groups: 96 patients underwent PCI and 117 underwent CABG. Clinical characteristics were obtained from electronic medical records, and follow-up was performed through both medical records and telephone calls. Events considered included all-cause mortality and acute myocardial infarction (AMI), both during hospitalization and in follow-up. An adjusted Cox model was used to compare events between groups, employing the likelihood ratio test. A p-value < 0.05 was considered statistically significant. All calculations were performed using R version 4.3.0.

The characteristics of both patient groups are shown in Table 1. Intravascular imaging techniques (IVUS) were used in 94.8% of PCI cases. The overall five-year mortality was 13.5% in the PCI group and 13.7% in the CABG group. Figure 1 (Panel A) shows the Kaplan-Meier survival curves. In the adjusted Cox model, no statistically significant difference was found for this outcome (HR 0.89, 95% CI 0.44–2.77, p=0.82). Conversely, the overall incidence of AMI during follow-up was 9.4% in the PCI group and 3.0% in the CABG group, as shown in Figure 1 (Panel B), with a statistically significant difference observed in the adjusted Cox model (HR 0.10, 95% CI 0.01–0.87, p = 0.037).

The findings of our analysis are consistent with those of meta-analyses of randomised clinical trials, showing that the risk of death is similar between CABG and PCI in patients with LMCA disease, although PCI is associated with a higher long- term risk of myocardial infarction.