The Utility of Concomitant ECMO and IABP as a Bridge to Heart Transplant

Abstract

<h3>Purpose</h3> Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used to bridge patients to orthotopic heart transplantation (OHT). However, there is scarce data on concomitant venting using intra-aortic balloon pumps (IABP). We sought to compare OHT-recipients bridged with VA-ECMO-alone versus VA-ECMO+IABP. <h3>Methods</h3> The UNOS database was used to analyze adult OHT recipients bridged with VA-ECMO between 1/1/2011 and 11/30/2020. Patients were grouped as being supported by VA-ECMO or by VA-ECMO+IABP at the time of transplant. <h3>Results</h3> In total, 316 patients were included, of whom 250 (79%) were supported by ECMO and 66 (21%) by ECMO+IABP. Recipient age, gender, ethnicity, BMI, smoking history, primary diagnosis, creatinine, and ECMO duration did not vary between cohorts. At the time of listing, ECMO+IABP patients were more likely to be ventilated (40 [16%] vs 20 [30.3%], p=0.008), dependent on IABP (32 [12.8%] vs 39 [59.1%], p <0.001), and require inotropy (118 [47.2%] vs 39 [59.1%], p=0.086) than patients on ECMO alone to achieve similar hemodynamics. At time of transplant, ECMO+IABP achieved similar hemodynamics as ECMO alone, as measured by cardiac output (3.7 [2.8-5.1] vs 3.9 [2.9-5.0] L/min), PA systolic pressure (38 [31-48] vs 40 [34-52.5] mmHg), PA mean pressure (27 [20.5-34.5] vs 30 [23-38] mmHg), and PCWP (21 [14-27] vs 23 [16-28] mmHg) (all p=ns). There was no difference in post-transplant incidence of dialysis (58 [23.2%] vs 16 [24.2%], p=0.865) and stroke (23 [9.2%] vs 6 [9.1%], p=0.669), or length of stay (21.5 [15-35] vs 22 [13-34] days, p=0.430). Post-transplant survival was similar between groups (Figure 1, p=0.783). <h3>Conclusion</h3> While a greater array of life-support interventions was required at listing by the ECMO+IABP group than the ECMO-alone group, both had similar hemodynamic profiles at time of transplant. With no difference in post transplant survival, these findings suggest that combination ECMO+IABP support can take more critically ill patients to transplant and achieve comparable outcomes.