CABG in 2012: Evidence, practice and the evolution of guidelines.
In the management of coronary artery disease (CAD) it is important to ensure that all patients are receiving optimal medical therapy irrespective of whether any intervention, by stents or surgery, is planned. Furthermore it is important to establish if a proposed intervention is for symptomatic and/or prognostic reasons. The latter can only be justified if there is demonstration of a significant volume of ischaemia (>10% of myocardial mass). Taking together evidence from the most definitive randomized trial and its registry component (SYNTAX), almost 79% of patients with three vessel CAD and almost two thirds of patients with LMS disease have a survival benefit and marked reduction in the need for repeat revascularisation with CABG in comparison to stents, implying that CABG is still the treatment of choice for most of these patients. This conclusion which is apparently at odds with the results of most previous trials of stenting and surgery but entirely consistent with the findings of large propensity matched registries can be explained by the fact that SYNTAX enrolled 'real life' patients rather than the highly select patients usually enrolled in previous trials. SYNTAX also shows that for patients with less severe coronary artery disease there is no difference in survival between CABG and stents but a lower incidence of repeat revascularisation with CABG. At three years, SYNTAX shows no difference in stroke between CABG and stents for three-vessel disease but a higher incidence of stroke with CABG in patients with left main stem disease. In contrast the PRECOMBAT trial of stents and CABG in patients with left main stem disease showed no excess of mortality or stroke with CABG in comparison to stents in relatively low risk patients. Finally the importance of guidelines and multidisciplinary/heart teams in making recommendations for interventions is emphasised.