PCI or CABG equally good revascularization strategy for left main disease in patients with or without ACS

The pooled analysis of four RCTs (randomized clinical trials) revealed that ACS patients had higher rates of early cardiovascular death and more comorbidities over five years. CABG and PCI resulted in similar all-cause death rates over five years, irrespective of ACS.

Patients presenting with left main coronary artery disease and an ACS represent a high-risk group of patients with atherosclerosis. The optimal revascularization strategy, however, remains debated, and theoretical arguments have been made to support both surgical and percutaneous revascularization strategies in ACS.

Previous studies evaluating coronary revascularization in ACS patients have almost excluded those with the left main disease. No RCTs have been comparing cardiovascular (CV) outcomes after CABG versus PCI, particularly in patients with the left main disease and ACS. Prakriti Gaba, Harvard Medical School, Boston, Massachusetts, and colleagues aimed to assess clinical outcomes after PCI vs CABG in patients with the left main disease with vs without ACS to address the knowledge gap.

For this purpose, the researchers pooled data from four trials comparing PCI with drug-eluting stents versus CABG in patients with left main disease considered equally suitable candidates for either strategy. Patients were categorized as presenting with or without acute coronary syndrome. Patients were enrolled in individual trials from 2014 to 2015. The authors pooled individual patient data from the trials and reconciled them from 2020 to 2021, and the analyses of the ACS subgroup were performed.

The study's primary outcome was death over five years. Secondary outcomes were spontaneous myocardial infarction (MI), cardiovascular death, stroke, repeat revascularization, and procedural MI.

The study revealed the following findings:

• Among 4394 patients (median age, 66 years; 76.7% male) randomized to receive PCI or CABG, 33% had ACS.
• ACS patients were likelier to have diabetes, prior MI, left ventricular ejection fraction less than 50%, and higher SYNTAX scores.
• At 30 days, patients with ACS had higher all-cause death (hazard ratio [HR], 3.40) and cardiovascular death (HR, 3.21) compared with those without ACS. Patients with ACS also had higher rates of spontaneous MI (HR, 1.70) through 5 years.
• All-cause mortality rates through 5 years with PCI vs CABG were 10.9% vs 11.5% (HR, 0.93) in patients with ACS and 11.3% vs 9.6% (HR, 1.19) among patients without ACS.
• The risk of early stroke was lower with PCI vs CABG (ACS: HR, 0.39; no ACS: HR, 0.35), whereas the 5-year risks of spontaneous MI and repeat revascularization were higher with PCI vs CABG (spontaneous MI: ACS: HR, 1.74; no ACS: HR, 3.03; repeat revascularization: ACS: HR, 1.57; no ACS: HR, 1.90), irrespective of ACS status.

"Among largely stable patients undergoing left main revascularization and with predominantly low to intermediate coronary anatomical complexity, those with ACS had higher rates of early death," the researchers wrote. "Nonetheless, all-cause mortality rates through 5 years were similar with PCI versus CABG in this high-risk subgroup."

"The relative disadvantages and advantages of PCI versus CABG regarding early stroke, long-term spontaneous MI, and repeat revascularization were consistent irrespective of ACS status."

"Our findings suggest that both CABG and PCI appear to be reasonable options for a heart team discussion in patients with left main disease presenting with or without ACS who do not require emergent revascularization," they concluded.

Reference:

Gaba P, Christiansen EH, Nielsen PH, et al. Percutaneous Coronary Intervention vs Coronary Artery Bypass Graft Surgery for Left Main Disease in Patients With and Without Acute Coronary Syndromes: A Pooled Analysis of 4 Randomized Clinical Trials. JAMA Cardiol. Published online May 31, 2023. doi:10.1001/jamacardio.2023.1177