Impact of coronary bypass or stenting on mortality and myocardial infarction in stable coronary artery disease.

BACKGROUND

To assess whether coronary bypass (CABG) or stenting reduce the risk of mortality and myocardial infarction (MI) compared with optimal medical therapy (OMT) in stable coronary artery disease (CAD).

METHODS

We performed a systematic review and network meta-analysis of contemporary randomized controlled trials comparing OMT, CABG and different stent types in stable CAD. All-comer trials were included if the rate of patients with acute myocardial infarction (AMI) was≤20%. Endpoints were all-cause mortality and MI.

RESULTS

Ninety-seven trials including 75,754 patients were analyzed at a weighted mean follow up of 42.5 months. Compared to OMT, CABG was associated with a lower risk of death (OR = 0.84; 95%CI:0.71-0.97). After exclusion of trials in left main and/or multivessel disease(LM/MVD) this benefit was not statistically significant (OR = 0.89; 95%CI:0.74-1.06). CABG was associated with a lower risk of MI (OR = 0.67;95%CI: 0.49-0.91) showing, however, a certain degree of inconsistency (p=0.10). None of the stent types included was associated with a lower risk of death. However, durable-polymer-CoCr-everolimus-eluting stent, by mixed evidence, after exclusion of either LM/MVD (OR = 0.73;95%CI: 0.54-0.98) or all-comer/post-MI trials (OR = 0.62;95%CI:0.39-0.98) was associated with a lower risk of MI than OMT. Similar findings, by indirect evidence, were confirmed for bio-absorbable-polymer-CoCr-sirolimus eluting stent (LMV/MVD trials excluded OR = 0.46; 95%CI = 0.29-0.74, all-comer/post-MI trials excluded: OR = 0.41;95%CI:0.22-0.79).

CONCLUSIONS

In stable CAD, CABG reduces the risk of mortality and MI compared to OMT, especially in patients with higher extent of CAD. Our study suggests that some of second and latest-generation drug-eluting stents may reduce the risk of MI. Future research should confirm these latter findings.