Effect of clinical trials on survival after heart transplantation

The application of clinical trials (CTs) to daily practice is based on the assumption that the patients included in these trials are similar to those seen on a daily basis. We performed a retrospective study to evaluate patient survival depending on whether they were included in a CT. We studied 217 patients who underwent heart transplantation (HT) between January 2000 and September 2006. We excluded patients who received combination transplants, those who underwent repeat HT, and pediatric patients who underwent HT. In total, 54 patients were included in a CT and 163 were not (NCT). The statistical tests included the t test, the chi(2) test and the Kaplan-Meier method.

Patients in the NCT group were in worse condition at HT, with a greater percentage of inotropic treatments pre-HT (36% vs 17%; P = .005), emergency transplants procedures (30% vs 13%; P = .01), and worse functional status pre-HT (P = .03). The NCT group exhibited lower survival (80.37% vs 87.04%; P = 0.13, log-rank test). There were no significant differences in the other analyzed variables.

Patients included in CTs tend to have better long-term survival rates, for several reasons: patients in the CT group were more stable at HT (selection bias), and the close follow-up of patients in CTs makes it more likely that any complication will be detected and treated early (follow-up bias).