Myocardial protection in heart transplantation using blood cardioplegia: 12-year outcome of a prospective randomized trial.

BACKGROUND

Blood cardioplegia yields a lower prevalence of right heart failure, arrhythmias, and myocardial ischemia early after heart transplantation (HTx). Because depolarizing (high [K(+)]) cardioplegic solutions may alledgedly cause endothelial damage, the 12-year outcome of a prospective randomized trial was reviewed.

METHODS

Between January 1997 and March 1998, 47 consecutive patients received crystalloid (Group 1, n = 27) or blood cardioplegia (Group 2, n = 20). The groups were similarly matched: recipient age (54 ± 11 vs 55 ± 7 years, p = 0.9), sex (89% vs 90% males, p = 0.9), diagnosis (63% vs 65% dilated cardiomyopathy, p = 0.8), elevated (>4 WU) pulmonary vascular resistance (30% vs 30%, p = 0.9), prior operations (22% vs 30%, p = 0.5), urgent HTx (7% vs 20%, p = 0.2), donor age (32 ± 11 vs 31 ± 13 years, p = 0.7), donor sex (78% vs 70% males, p = 0.5), donor cause of death (33% vs 40% vascular, p = 0.5), and global myocardial ischemia (176 ± 51 vs 180 ± 58 minutes p = 0.5). Hemodynamically unstable donors were more prevalent in Group 2 (15% vs 45%, p = 0.02). The 45 hospital survivors underwent yearly echocardiography, coronary angiography, and coronary intravascular ultrasound (IVUS) imaging during follow-up.

RESULTS

During follow-up (10.4 ± 5.2, range, 0.9-12.7 years), Groups 1 and 2 had comparable mortality (46% vs 42%, p = 0.7) and cause of death (chronic rejection: 50% vs 50%; neoplasia: 33% vs 25%, p = 0.8). Survival at 12 years was 50% ± 12% vs 52% ± 11% (p = 0.9). Follow-up echocardiogram showed similar mean left ventricular ejection fraction (LVEF; 47% ± 12% vs 49% ± 11%, p = 0.7) and prevalence of LVEF < 35% (21% vs 18%, p = 0.8). Prevalence of chronic rejection was comparable (42% vs 32%, p = 0.1), yet severe allograft vasculopathy (International Society for Heart and Lung Transplantation cardiac allograft vasculopathy 3) was more prevalent in Group 1 (64% vs 17%, p = 0.04). Freedom from chronic rejection was higher in Group 2 (44% ± 15% vs 63% ± 13%), albeit not significantly (p = 0.5). A trend toward greater prevalence of intimal disease at IVUS (thickness > 0.5 mm) in the proximal and distal left anterior descending artery (67% vs 40%; 58% vs 45%) and higher number of percutaneous coronary interventions (2.7 ± 0.5 vs 1.8 ± 0.3, p = 0.3) was noted in Group 1.

CONCLUSIONS

Use of blood cardioplegia is safe and results in comparable survival and prevalence of adverse events late after HTx. The trend towards greater freedom from chronic rejection and more limited extent of coronary artery disease in grafts protected with blood cardioplegia awaits confirmation.