Hybrid coronary revascularization: a mainstream revascularization strategy in the future?

In stable patients with multivessel coronary artery disease (CAD), coronary bypass operation (coronary artery bypass grafting [CABG]) has been found to be superior to percutaneous coronary intervention (PCI) using drug-eluting stents (DES) [1–3]. The finding is based on wellpowered randomized studies [4,5] and large-scale registries [6,7]. The superiority of CABG is demonstrated by lower shortand long-term rates of repeat revascularization, myocardial infarction (MI) and death, which were pronounced in patients with complex coronary artery lesions. With equal consistency, short-term stroke rates have been found to be lower in PCIthan in CABG-treated patients [4,5,8]. Coronary revascularization is a moving target. Coronary stents are undergoing continuous improvements resulting in enhanced deliverability and long-term safety as compared with the first-generation sirolimus-eluting CypherTM (Cordis, FL, USA) and paclitaxel-eluting TaxusTM (Boston Scientific, MA, USA) stents used in the SYNTAX [5] and the FREEDOM [4] trials, respectively. Similarly, up-to-date antithrombotic treatment is likely to improve the short-term outcome of catheter-based revascularization [3]. On the surgical side, the combination of off-pump techniques and total arterial grafting promises a strategy to improve long-term outcome and reduce neurologic complications by avoidance of aortic manipulation [9–11]. In addition, minimally invasive techniques diminish the surgical trauma and bleeding [12,13]. These changes are not likely to change the overall results of the abovementioned landmark trials. Substantial evidence indicates that left internal mammary artery (LIMA) grafting of the left anterior descending coronary artery (LAD) is the main determinant of the beneficial survival effect of CABG [14,15]. Therefore, current revascular ization guidelines recommend CABG as the preferred treatment in patients with CAD with the exception of patients with oneor two-vessel disease without proximal LAD involvement [1–3]. The benefit of nonmammary artery conduits to non-LAD vessels is less clear, and the poor longevity, especially of saphenous vein grafts (SVG), may favor the use of PCI using DES in non-LAD territories [16,17]. The possible superiority of DES treatment as compared with grafting of non-LAD lesions using SVGs or arterial conduits remains to be addressed in randomized clinical trials. The fundamental rationale of hybrid coronary revascularization (HCR) is to combine the prognostic benefits of the LIMA-to-LAD graft with minimal invasiveness and reduction of stroke risk. The concept of HCR has been assessed in a number of case reports and registry studies [18–30]. To date, HCR has mainly been used in patient subsets with a Revascularization by coronary artery bypass grafting is superior to percutaneous coronary intervention in cases of complex multivessel coronary artery disease. The superiority is demonstrated by reduced rates of repeat revascularization, myocardial infarction and all-cause death. By contrast, stroke occurs more frequently after coronary artery bypass grafting. Hybrid coronary revascularization combines the survival benefits of left internal mammary artery-to-left anterior descending coronary artery grafting, fast recovery and minimized surgical trauma, reduced risk of stroke by avoidance of aortic manipulation and the longterm patency of drug-eluting stent treatment of left anterior descending coronary artery lesions. Accordingly, results from registry studies are compatible with the shortand long-term superiority of hybrid coronary revascularization as compared with conventional revascularization using percutaneous coronary intervention or coronary artery bypass grafting.