The effect of myocardial preservation technique on operative mortality in complex valvular heart disease.

Between November, 1964 and January, 1983, 70 consecutive patients underwent primary repair of complex valvular heart disease, defined as repair or replacement of two or more cardiac values alone or with other concomitant cardiac procedures. A total of 163 operative procedures were performed on the 70 patients for an average of 2.33 procedures per patient. Review of these cases allowed the patients to be divided into two distinct groups, those receiving systemic hypothermia and cold potassium cardioplegic arrest of the heart (C) and those having other myocardial preservation techniques (NC). Thirty-three patients received C and are compared with 37 patients who received NC. The two patient groups were comparable when considered for preoperative cardiac index and functional classification though patients in C group were older. In the C group, 10 of 32 patients (31%) had associated coronary artery bypass grafting in contrast to 2 of 37 patients (5.4%) in the NC era. The mortality of the C group was 2 of 33 (6%) vs 14 of 37 (37.8%) in the NC group (P less than .001). Of the 14 deaths in the NC patients, 10 were due to low cardiac output syndrome. While other factors have undoubtedly played a role, improved myocardial preservation by the use of C and attention to coronary artery pathology may have contributed to the improved operative mortality in this group of patients with complex valvular heart disease.