IJCS | Volume 31, Nº2, March / April 2018

154 Study or Subgroup Stent Events Total Events Total CABG Weight Risk Difference Risk Difference M-H, Fixed, 95% CI M-H, Fixed, 95% CI –0.2 –0.1 0.2 0 0.1 Favours stent Favours CABG Heterogeneity: Chi 2 = 3.65, df = 6 (p = 0.72); I 2 = 0% Test for overall effect: Z = 2.83 (p = 0.005) Total events 26 51 BEST 2015 3 438 7 442 9.7% –0.01 [–0.02, 0.00] Boudriot et al. 2011 0 100 1 101 2.2% –0.01 [–0.04, 0.02] EXCEL 2010 9 948 10 957 21.9% –0.00 [–0.01, 0.01] FREEDOM 2012 8 953 15 947 20.9% –0.01 [–0.02, 0.00] NOBLE 2016 2 592 7 592 13.0% –0.01 [–0.02, 0.00] Subtotal (95 CI) 3383 74.7% 3392 –0.01 [–0.01, –0.00] PRECOMBAT 2011 4 300 9 300 6.6% –0.02 [–0.04, 0.01] LE MANS 2008 0 52 2 53 1.2% –0.04 [–0.10, 0.02] Figure 1 – Mortality at 30 days: stent versus coronary artery bypass grafting. The size of the squares is proportional to the number of patients. The bars represent 95% confidence intervals. The diamond represents the synthesis of the results. Abbreviations: CABG: coronary artery bypass grafting; LE MANS: Left Main Coronary Artery Stenting; FREEDOM: Future Revascularization Evaluation in Patients with Diabetes Mellitus; BEST: Bypass Surgery and Everolimus-Eluting Stent Implantation in the Treatment of Patients with Multivessel Coronary Artery Disease; PRECOMBAT: Premier of Randomized Comparison of Bypass Surgery versus Angioplasty Using Sirolimus-Eluting Stent in Patients with Left Main Coronary Artery Disease; EXCEL: Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization; NOBLE: Nordic-Baltic-British Left Main Revascularization; Boudriot: study by Boudriot et al.: J Am Coll Cardiol. 2011; 57: 538-545 . Graph obtained using the software Review Manager (RevMan), version 5.3. Andrade et al. Stent versus surgery: randomized trials Int J Cardiovasc Sci. 2018;31(2)152-162 Original Article score (reported in seven studies) was 26. In regards to the number of affected vessels, 7%affected only two vessels, 43% affected only three vessels, and 50%presented obstruction of the left main coronary artery, associated or not with disease in other vessels. Some characteristics of the studies deserve special mention: the LE MANS 1 used drug-eluting and bare-metal stents, reserving the drug-eluting stents for left main coronary arteries with a reference diameter < 3.8 mm; CARDia 4 used initially bare-metal stents and only assessed patients with diabetes and multivessel disease; SYNTAX 2 evaluated left main coronary artery obstruction and multivessel disease and used first‑generation drug-eluting stents (TAXUS); FREEDOM 8 and VA CARDS 7 exclusively assessed patients with diabetes and multivessel disease; BEST 9 evaluated patients withmultivessel disease and used only everolimus-eluting stents; the study by Boudriot et al. 5 evaluated left main coronary artery obstruction and used only sirolimus-eluting stents; EXCEL 11 evaluated left main coronary artery obstruction and used only everolimus- eluting stents; NOBLE 10 evaluated left main coronary artery obstruction and used mostly a biolimus‑eluting stent. Outcomes The outcomes are summarized in Figures 1 to 6. The incidence of stroke up to 1 year had a low heterogeneity (I 2 = 0). The results favored PCI (0.4% versus 1.5%, p < 0.00001). In regards to 30-day mortality, the studies showed low heterogeneity (I 2  = 0) and favored the stent group (0.8% versus 1.5%, p = 0.005). As for mortality up to 1 year, the studies presented low heterogeneity (I 2  = 0%) and no difference between the groups (3.4% versus 3.5%, p = 0.50). In late mortality, the studies showed low heterogeneity (I 2  = 0%) and favored CABG (10.1% versus 8.5%, p = 0.01). After exclusion of patients with diabetes from four studies (SYNTAX, 2 FREEDOM, 8 BEST, 9 and CARDIa 4 ), the differences in late mortality tended to disappear (8.5% versus 8.1%, p = 0.6). In the six studies evaluating left main coronary artery obstruction (LE MANS, 1 SYNTAX LEFT MAIN, 12 PRECOMBAT, 6 EXCEL, 11 NOBLE, 10 and the study by Boudriot et al. 5 ) totaling 4700 patients, there was no difference in mortality at 30 days (0.8% versus 1.4%, p = 0.15), 1 year (3.0% versus 3.7%, p = 0.18), or in late mortality (8.1% versus 8.1%). There was a significant difference in favor of the stent group in the incidence of stroke (0.3% versus 1.5%, p < 0.0001). Four studies reported late mortality in patients with diabetes (SYNTAX, 3 CARDIa, 4 FREEDOM, 8 andBEST 9 ). In the combined results (n = 3223), mortality up to 5 years was 12.5% in the stent group versus 9.7% in the surgery group (p< 0.0001). Five studies provided the outcomes of the late incidence of combined adverse events (MACCE) divided into subgroups, which are represented in Figure 7. The combined MACCE outcomes in these subgroups (Figure 7) show that a SYNTAX