Does simultaneous antegrade and retrograde cardioplegia improve functionalrecovery and myocardial homeostasis?

Background: The purpose of our research was to evaluate the functional reco very and homeostasis of myocardium during simultaneous continuous retrograd e and antegrade cardioplegia versus continuous retrograde cardioplegia. Met hods: Forty patients who underwent elective coronary artery bypass grafting (CABG) were prospectively assigned to two clinically matched groups and an alyzed in respect to cardioplegia protocol. Group I consisted of 24 patient s who received continuous retrograde blood cardioplegia; Group II consisted of 16 patients who received simultaneous continuous ante- and retrograde c ardioplegia. Hydrogen ion release, carbon dioxide, lactate concentration ox ygen content, and oxygen extraction were measured from coronary sinus efflu ent and from the arterial line before and after cross-clamping of the aorta . Median changes of these parameters were reported. Cardiac output was meas ured and left and right ventricle stroke works were calculated. Incidence o f low cardiac output, ventricular fibrillation, raised cardiac enzymes, and ischemic changes on electrocardiogram (ECG) were noted. Results: In the si multaneous group, oxygen content and oxygen extraction recovered well after cross-clamping. The same parameters did not recover to the same extent in the retrograde group. These changes were notable between groups. Hydrogen i on, carbon dioxide, and lactate releases were comparable between groups. Tr end toward better recovery of left ventricle stroke work index was encounte red in the simultaneous group. Conclusions: Viability of myocardium measure d with oxygen utilization and functional recovery is better preserved with simultaneous antegrade and retrograde cardioplegia. However, there is no di fference in anaerobic metabolism markers. Thus simultaneous ante- and retro grade cardioplegia is probably advantageous over retrograde alone.