Cardiomyocyte Apoptosis Following Antegrade and Retrograde Cardioplegia

Retrograde cardioplegia during heart surgery is associated with inadequate myocardial protection. In experimental animal study retrograde cardioplegia induces more cardiomyocyte apoptosis when compared to antegrade cardioplegia. 20 volunteer patients under going elective aortic valve surgery will be divided in to two groups: 10 patients receiving only antegrade cardioplegia and 10 patients receiving only retrograde cardioplegia. Pre- and post-operatively cardiac MRI and cardiac ultrasound will be performed. During the surgery ventricular muscle samples will be taken in order to assess cardiomyocyte apoptosis. Aims of the study: 1. whether the cardiomyocyte apoptosis is significantly more induced after retrograde cardioplegia than antegrade cardioplegia, 2. whether the amount of apoptotic cardiomyocytes correlates to conventional markers of myocardial injury after cardiac surgery, 3. whether the extent of irreversible myocardial damage by apoptosis correlates to post-ischemic contractile dysfunction after cardiac surgery, as measured with echocardiography, 4. whether the amount of cardiomyocyte apoptosis correlates to long term outcome and cardiac function as measured with MRI.