Factors associated with long-term survival following cardiac transplantation

By improving short and long-term survivals, cardiac transplantation would be a more realistic curative treatment modality. The aim of this study was to evaluate factors associated with the long-term survival following cardiac transplantations in our center.

Forty-four patients were operated on cardiac transplantation between 1989 and November 2006. The study was designed in a retrospective manner and all data were collected from hospital records. Our study population consisted of 16 patients (Group A) who survived >1 month, but died <2 years after cardiac transplantation and 17 patients (Group B) who survived more than 2 years. All patients had triple immunosuppressive therapy (cyclosporine, azathioprine, corticosteroid). Statistical analyses were performed using Fischer's exact and Mann Whitney U tests, and multivariate regression analysis. Survival was analyzed using Cox proportional hazard regression analysis.

Group B patients had lower pre-transplant creatinine levels (0.93+/-0.28 mg/dl vs. 1.16+/-0.21 mg/dl, p=0.033) younger donor age (24.5+/-6.3 years vs. 30.1+/-8.1 years, p=0.017) and more male donors (82.3% vs. 50%, p=0.05) as compared with Group A patients. The perioperative and follow-up analysis showed that patients with long-term survival had shorter ischemic time (141.5+/-33.2 min vs. 182.5+/-49.2 min, p=0.007), aortic cross clamp time (65.9+/-10.2 min vs. 83.6+/-7.9 min, p<0.001), less amount of blood transfusion (3.4+/-1.6 units vs. 5.0+/-1.5 units, p=0.01), better NYHA status after operation (1+/-0 vs. 1.63+/-0.72, p=0.014) and less frequent acute rejection episodes (11.8% vs. 68.8%, p<0.001) than those with short-term survival after operation. Cox proportional hazard regression analysis showed higher preoperative creatinine level (HR=42.6, 95% CI 4.67-388.21, p=0.001), acute rejection (HR=4.45, 95% 1.44-13.77, p=0.01), early postoperative functional status (HR=4.84, 95% CI 1.9-12.27, p=0.001) and unsatisfactory rejection surveillance protocol in the first 6 months after transplantation (HR=0.2, 95% CI 0.07-0.67, p=0.008) were prominent factors associated with the long-term survival.

The availability of the donor hearts from younger male donors with the shortest ischemic times is identified as the most significant factor improving long-term survival. The main strategy in cardiac transplantation should be shortening ischemic times and applying strict postoperative follow-up.