Reoperative sternotomy is associated with increased early mortality after cardiac transplantation

Outcomes of cardiac transplantation in patients undergoing reoperative sternotomy are often worse than primary transplants. However, the risks imposed by a prior sternotomy, left ventricular assist device (LVAD) or retransplantation have not been independently analysed.

Using the United Network for Organ Sharing (UNOS) database, a retrospective propensity-matched cohort analysis was performed on 14 730 patients who received a heart transplant between 2005 and 2017. Of 7365 patients who underwent a reoperative sternotomy, 4526 (61%) patients had previous cardiac surgery, 2364 (32%) patients had an LVAD and 475 (6%) patients had a previous transplant. Baseline characteristics were compared, and survival was analysed using a Cox model.

Compared to patients who underwent a primary transplant, patients with a prior sternotomy had a worse long-term survival (P < 0.001). There was no significant difference in survival between patients who had an LVAD and those who had a previous cardiac operation. However, all subgroups had better survival compared to patients who underwent a retransplant (P < 0.05). On the multivariable analysis, prior sternotomy and radiation demonstrated an increased risk of death compared to primary transplants [prior cardiac surgery: hazard ratio (HR) 1.13, 95% confidence interval (CI) 1.05-1.22; P = 0.001; LVAD: HR 1.19, 95% CI 1.08-1.32; P = 0.001; retransplant: HR 1.68, 95% CI 1.42-1.99; P < 0.001; radiation: HR 1.82, 95% CI 1.00-3.30; P = 0.04]. When excluding patients who died in the first year, there were no significant differences in survival between the primary transplant, prior cardiac surgery, LVAD and retransplant groups.

Prior sternotomy is a risk factor for worse survival after cardiac transplantation, mainly due to increased early postoperative mortality. A history of prior transplant confers the greatest risk compared to those who received an LVAD or had prior cardiac surgery.