The “Organ Care System (OCS)- Heart”-TransMedics (TM) is the only clinical platform for ex-vivo perfusion of human donor hearts, preserving the graft in a warm beating state. AIM: To analyze results of HTX performed with OCS.
From 2015 to 2018, 7 patients (mean age: 46y) received a donor heart (mean age: 39y) preserved with the OCS-Heart system. Ischemic, cardiopulmonary (CPB) bypass time and day-0/day-1 CK-MB levels (TM-group) were compared with those of 95 patients transplanted with the cold static storage (CSS-group). The OCS was used for expected long ischemic times or for adverse donor (cardiac arrest) or recipient (infected LVAD, ECMO and unusual anatomy) features.
Mean out-of-the-body perfusion time was 296 minutes. Overall ischemic time was 124 (TM-group) vs. 187 minutes in the CSS-group (P = 0.01). The OCS allowed to spare 159 minutes of estimated ischemia. D0/D1 CK-MB was 115 and 36 vs. 125 and 47 ng/ml in the CSS-group (P = NS). ICU stay was 20 days. Two patients died for hemorragic shock (LVAD recipient) and for multiorgan failure. One patient developed a severe right failure, treated by mechanical assistance, weaned after 8 days. Five recipients are alive at a mean FU of 18 months.
Ex-vivo perfusion of donor hearts is technically safe and permits a significant reduction of the ischemic time. A trend toward reduction of myocardial damage was observed when compared to CSS. The real impact in unfavourable donor-recipient combination needs further investigations. A potential expansion of donors’pool is predictable with this innovative system.
1De Gasperis Cardio Center, Niguarda Milano