Heart Preservation with the Organ Care System in Extended Criteria Donors: A Single-Center Experience

Objectives: The Organ Care System (OCS) Heart is noninferior to standard cold storage for preservation of donor hearts. We hypothesized that its properties for prolonged heart preservation might be especially beneficial for extended criteria donor (ECD) hearts.

Methods: Patients transplanted with ECD hearts preserved using the OCS Heart at our institution between October 2016 and September 2019 were prospectively followed up. ECD was defined as fulfilling at least one of the following criteria: age between 45 and 55 years without coronary angiography; age > 55 years; echocardiographic evidence of left ventricular hypertrophy (LVH); need for cardiopulmonary resuscitation (CPR) longer than 20 minutes; left ventricular ejection fraction (LVEF) <40%; evidence of coronary artery disease (CAD); carbon monoxide intoxication with preserved LVEF; moderate-severe alcohol consumption; diabetes mellitus without CAD.

Results: During the study period, the OCS Heart was employed in 49 out of 71 (69%) patients transplanted at our institution. Among these 49 patients, 37 (76%) patients transplanted with an ECD heart, as defined by the aforementioned criteria (median donor age, 49 years; LVH, n = 12; CPR, n = 17; mild CAD, n = 2; LVEF <  40%, n = 1; alcohol consumption, n = 18), were considered in the study. Twelve (32%) retrievals were performed outside Germany (Northern Ireland, England, Austria, Lithuania, Hungary, and Croatia).

Before transplantation, 35 (95%) recipients had a median of 1 previous cardiac operations (LVAD/BVAD, n = 28; other cardiac operations, n = 7), 4 (11%) were on ECLS, and 34 (92%) were on the high urgency waiting list. All ECD hearts were successfully transplanted. Median OCS perfusion and out-of-body times were 4.6 and 6.6 hours, respectively.

Postoperatively, 6 (16%) and 28 (76%) patients required rethoracotomy for bleeding and dialysis (temporary, n = 23), respectively. Nine (24%) patients required postoperative ECLS, due to severe PGD in five cases. Four (11%) patients died in the hospital (CPR of unknown reason, n = 1; acute pancreatitis, n = 3). At discharge, all patients showed a LVEF > 60% in echocardiography. At 2-year follow-up, survival and freedom from biopsy-confirmed rejection (ISHLT grade > 1R) were 74 and 86%, respectively.

Conclusion: OCS Heart allowed safe transplantation of extended criteria donor hearts. Despite out-of-body time was approaching 7 hours, enabling allocations otherwise not acceptable, patient and graft outcomes were favorable.

No conflict of interest has been declared by the author(s).