Purpose: The purpose of this investigation was to find out whether the addition of aspartate and glutamate improved the myocardial protection afforded by a normothermic blood cardioplegia solution given anterograde, at 20 minute intervals. Methods: After a 60 minute period of amino-acid enriched cardioplegic arrest, 10 rabbit hearts were processed for metabolic studies (phase1), while another 10 were reperfused parabiotically with arterial blood and then submitted to biochemical and functional analyses (phase 2). Ventricular myocardium glycogen concentration and mitochondrial respiration were determined for both phases. Left ventricular contractility (dP/dtmax) was assessed during reperfusion in phase 2 animals. Results: Compared to control levels, non reperfused (phase 1) with and without aminoacids hearts showed a similar and significant drop in glycogen levels (53 % and 58%, respectively). There was no significant difference concerning mitochondrial respiration and myocardial contractility (dP/dtmax) between the experimental groups with and without aminoacids and between these and the control groups. Conclusion: The addiction of aspartate and glutamate to an "in vitro" intermittent anterograde normothermic (37°C) blood cardioplegia rabbit model did not improve myocardial protection in this study.
Pressão ventricular; Heart arrest; Heart arrest; Amino acids; Myocardium; Myocardium; Myocardium; Ventricular pressure
