Percutaneous vs. surgical revascularization for patients with unprotected left main stenosis: a meta-analysis of 5-year follow-up randomized controlled trials

Abstract

Aims: A 5-year survival of patients with unprotected left main (ULM) stenosis according to the choice of revascularization (percutaneous vs. surgical) remains to be defined.

Methods and results: Randomized controlled trials (RCTs) comparing percutaneous coronary intervention (PCI) vs. coronary artery bypass graft (CABG) with a follow-up of at least 5 years were included. All-cause death was the primary endpoint. MACCE [a composite endpoint of all-cause mortality, myocardial infarction (MI), stroke, and repeat revascularization] along with its single components and cardiovascular (CV) death were the secondary ones. Analyses were stratified according to the use of first- vs. last-generation coronary stents. Subgroup comparisons were performed according to SYNTAX score (below or above 33) and to age (using cut-offs of each trial's subgroup analysis). Four RCTs with 4394 patients were identified: 2197 were treated with CABG, 657 with first generation, and 1540 with last-generation stents. At 5-year rates of all-cause death did not differ [odds ratio (OR) 0.93, 95% confidence interval (CI) 0.71-1.21], as those of CV death and stroke. Coronary artery bypass graft reduced rates of MACCE (OR 0.69, 95% CI 0.60-0.79), mainly driven by MI (OR 0.48, 95% CI 0.36-0.65) and revascularization (OR 0.53, 95% CI 0.45-0.64). Benefit of CABG for MACCE was consistent, although with different extent, across values of SYNTAX score (OR 0.76, 95% CI 0.59-0.97 for values < 32 and OR 0.63, 95% CI 0.47-0.84 for values ≥ 33) while was not evident for 'younger' patients (OR 0.83, 95% CI 0.65-1.07 vs. OR 0.65, 95% CI 0.51-0.84 for 'older' patients).

Conclusion: For patients with ULM disease followed-up for 5 years, no significant difference was observed in all-cause and cardiovascular death between PCI and CABG. Coronary artery bypass graft reduced risk of MI, revascularization, and MACCE especially in older patients and in those with complex coronary disease and a high SYNTAX score.

Keywords: Coronary artery bypass graft; Coronary artery disease; Meta-analysis; Percutaneous coronary intervention; Unprotected left main.

Figure 1

Five-year rates of all-cause death in coronary artery bypass graft vs. percutaneous coronary intervention. Random effect risk estimates with 95% confidence intervals for all-cause death and stroke. CABG, coronary artery bypass graft; CI, confidence intervals; DES, drug-eluting stents; PCI, percutaneous coronary intervention.

Figure 2

Five-year major adverse cardiovascular and cerebrovascular events (A), myocardial infarction (B), and revascularization (C) rates in patients treated on unprotected left main coronary artery with coronary artery bypass graft vs. percutaneous coronary intervention. Random effect risk estimates with 95% confidence intervals for major adverse cardiovascular and cerebrovascular events, myocardial infarction, and revascularization. Major adverse cardiovascular and cerebrovascular events included the original primary endpoint of PRECOMBAT, NOBLE, and SYNTAX LM (all-cause death, myocardial infarction, stroke, and revascularization), whereas, for EXCEL, a secondary prespecified endpoint was adopted to include revascularization. In NOBLE trial data about periprocedural myocardial infarction were not collected, PRECOMBAT and SYNTAX LM provided only aggregate data of procedural and non-procedural myocardial infarction; thus the myocardial infarction outcome is shown in B embrace all myocardial infarction occurring during follow-up for studies with first-generation drug-eluting stents (PRECOMBAT and SYNTAX LM) and only non-procedural myocardial infarction for randomized controlled trials with second-generation drug-eluting stents (NOBLE and EXCEL). CABG, coronary artery bypass graft; CI, confidence intervals; DES, drug-eluting stents; PCI, percutaneous coronary intervention.

Figure 3

Five-year cardiovascular death (A) and stroke (B) in patients with unprotected left main coronary disease treated with coronary artery bypass graft vs. percutaneous coronary intervention. Random effect risk estimates with 95% confidence intervals for cardiovascular death. CABG, coronary artery bypass graft; CI, confidence intervals; DES, drug-eluting stents; PCI, percutaneous coronary intervention.

Figure 4

Major adverse cardiovascular and cerebrovascular events in patients with ULMCAD treated with coronary artery bypass graft or percutaneous coronary intervention according to SYNTAX score. Random effect risk estimates with 95% confidence intervals for trial-defined major adverse cardiovascular and cerebrovascular events in low and intermediate SYNTAX score (SYNTAX score 0–32, A, above) and high SYNTAX score (SYNTAX score ≥ 33, B, below). Primary endpoints of each included trial were adopted for the outcome ‘trial-defined MACCE’ (i.e. not including revascularization in EXCEL trial). CABG, coronary artery bypass graft; CI, confidence intervals; DES, drug-eluting stents; PCI, percutaneous coronary intervention.

Figure 5

Major adverse cardiovascular and cerebrovascular events in patients with ULMCAD treated with coronary artery bypass graft or percutaneous coronary intervention according to age. Random-effect risk estimates with 95% confidence intervals for major adverse cardiovascular and cerebrovascular events in ‘older’ patients (A) and ‘younger’ patients (B). ^aSubgroup analysis for age was not provided in SYNTAX LM. NOBLE and EXCEL compared outcomes in patients younger or older than 67 years old, whereas PRECOMBAT used age cut-off of 65 years old. CABG, coronary artery bypass graft; CI, confidence intervals; DES, drug-eluting stents; PCI, percutaneous coronary intervention.