Temporary mechanical circulatory support as a bridge to transplant in peripartum cardiomyopathy

Background Use of temporary mechanical circulatory support (tMCS) for peripartum cardiomyopathy (PPCM) shock has been described in small cohorts, but not on a national scale. This study compares tMCS, durable MCS (dMCS), and no MCS as bridge to transplant strategies for PPCM. Methods Female patients ≥14 years, listed for first-time isolated heart transplant (HT) between January 1, 2000 and June 30, 2021, were identified in the United Network for Organ Sharing database. Patients were stratified by receipt of MCS at any point during the waitlist period. Patients on multiple devices were excluded. Results A total of 1,043 PPCM patients were listed for HT, including 575 bridged on no MCS, 177 on tMCS, and 291 on dMCS. The tMCS cohort included 10 patients on extracorporeal membrane oxygenation, 113 on intra-aortic balloon pump, and 54 on nondischargeable ventricular assist device (VAD) or percutaneous device. The dMCS group primarily received durable VADs. Compared to dMCS, tMCS recipients were more likely to require inotropes, mechanical ventilation, and longer hospitalizations pretransplant (all p < 0.001). tMCS patients were more likely to be transplanted after 6 months than those on no device (adjusted subhazard ratio 1.57 [1.24-2.01]). Six hundred and eighty-one patients underwent HT. tMCS support was associated with similar 3-year graft survival compared to no MCS and dMCS (both p > 0.05). After multivariable risk adjustment, neither tMCS (adjusted hazard ratio 0.56 [0.06-5.43]) nor dMCS (adjusted hazard ratio 0.36 [0.05-2.82]) significantly predicted 3-year graft survival. Conclusions Compared to patients bridged to HT on dMCS or no MCS, PPCM patients receiving tMCS are higher acuity candidates but have equivalent post-transplant graft survival.