Incidence of late atrial fibrillation in bilateral lung versus heart transplants

BACKGROUND: We compared the incidence of late-onset atrial fibrillation in orthotopic heart transplant recipients and bilateral orthotopic lung transplant recipients. METHODS: We reviewed the records of all heart and lung transplant operations carried out in our institution between 1995 and 2015. We performed 1:1 propensity-matching based on patient age, sex, body mass index, and hypertension. Our primary outcome, late-onset atrial fibrillation, was defined as atrial fibrillation occurring after discharge following hospitalization for transplantation. RESULTS: Over the study period, 397 orthotopic heart transplants and 240 bilateral orthotopic lung transplants were performed. Propensity matching resulted in 173 pairs who were matched with respect to age, sex, body mass index, and preoperative hypertension. The median follow-up was 5.3 years for heart transplant patients and 3.1 years for lung transplant patients. Late-onset atrial fibrillation occurred in 11 heart transplant patients (5 of whom had biopsy-proven evidence of rejection) and 19 lung transplant patients (2 of whom had biopsy-proven evidence of rejection). On Kaplan-Meier analysis, the probability of late-onset atrial fibrillation at 5 years was 4.3% for heart transplant patients vs. 13.9% for lung transplant patients (log-rank p = 0.01). CONCLUSIONS: We documented an increased probability of late-onset atrial fibrillation among bilateral orthotopic lung transplant patients compared to orthotopic heart transplant patients. This was a hypothesis-generating study that suggests a potential role for cardiac autonomic innervation in the genesis of atrial fibrillation.