Concomitant coronary artery disease (CAD) and valvular heart disease is a common problem in the ageing population. It is estimated that the prevalence of mitral regurgitation and aortic stenosis in individuals over the age of 70 is 10 % and 4 %, respectively.1,2 Among patients presenting with symptomatic aortic stenosis, concurrent CAD occurs in over 50 % of those over 70 years of age and over 65 % of those over 80 years of age.3,4 However, elderly patients often have more co-morbidities, are more likely to have had a previous cardiac operation, and are less tolerant of complex cardiac surgery. Furthermore, the addition of coronary artery bypass grafting (CABG) at the time of valve surgery doubles the operative risk of the procedure.5-8 Interest in hybrid procedures, defined for the purpose of this review as surgical valve repair/replacement and percutaneous coronary intervention (PCI) (hybrid valve), has intensified with the emergence of minimally invasive surgical techniques, improved coronary stent technology, increased collaboration between cardiac surgeons and interventional cardiologists, and the introduction of hybrid operating suites. The complementary goals of minimising the morbidity of surgical procedures and optimising resource utilisation have driven development of new solutions for concurrent valvular and coronary heart disease.
Indications and Patient Selection
The primary purpose of a hybrid valve/PCI is to substitute PCI for bypass grafting with saphenous vein grafts (SVGs), particularly for lesions not in the left anterior descending (LAD) coronary artery.5 With the current excellent performance of drug-eluting coronary stents (DES), restenosis and thrombosis rates of DES may be less than the estimated rate of SVG failure of 20 % at 12 months.9,10 The two most common clinical objectives of hybrid procedures are to facilitate minimally invasive surgery and to reduce overall operative morbidity and mortality by transforming a single, high-risk surgery into two less risky procedures. Minimally invasive valve surgery, via upper hemisternotomy for the aortic valve or right mini-thoracotomy for the mitral valve, has been shown to reduce operative pain, to require less blood transfusion, to provide a superior cosmetic result, and to be associated with faster recovery and a shorter hospital length of stay.5,10,11
Reoperative coronary bypass grafting in a patient with valvular disease poses a particular challenge in cardiac surgery. The hybrid approach is of particular benefit in reoperative patients who have had prior CABG with patent grafts.5,9,12 The technical difficulty of accessing lateral wall targets, safely dissecting patent bypass grafts and obtaining exposure often precludes safe surgery, and these risks are not reflected in traditional scoring systems. Hybrid valve/PCI may be particularly useful in this regard and can dramatically simplify a challenging open valve and CABG surgery by substituting PCI for reoperative bypass grafting in lesions amenable to PCI.5
Hybrid procedures offer a reasonable alternative to traditional surgery for patients who meet the following basic criteria: