Effects of Warm Cardioplegic Induction on Postoperative Left Ventricular Performance

A prospective study was performed in two groups of patients, to check the effectiveness of warm and cold cardioplegic induction in myocardial protection. Each group comprised 15 cases, and we used blood cardioplegia as a cardioplegic solution. In the first group warm induction, cold maintenance and terminal warm cardioplegia was used. In the second group, the only difference was cold cardioplegic induction. Cardiac index, pulmonary artery pressure, left ventricular stroke work index, pulmonary capillary wedge pressure measurements were done just after the operation, first postoperative day and the same day after volume loading. Findings were compared statistically by using Student t- test. Cardiac index and stroke work indices of patients in group 1 were found higher (p<0.01) than the patients in group 2. Furthermore, pulmonary artery pressures in group 1 were found lower (p<0.01). No patients in both groups had shown findings of postoperative myocardial infarction or low cardiac output. Thus in patients in whom warm induction was used, the myocardium appeared to be better protected and its response to volume loading was better. This confirms that cardioplegia with warm induction is superior to cardioplegia with cold induction in myocardial protection.