Direct comparison of mechanical circulatory support devices in porcine model of acute myocardial infarction complicated by ventricular septal defect and cardiogenic shock

Abstract Introduction Despite urgent clinical need, until now optimal strategy for mechanical circulatory support in acute myocardial infarction (AMI) complicated by ventricular septal defect (VSD) and cardiogenic shock has not been determined. Purpose The aim of our study was to compare hemodynamic effects of intra-aortic balloon pump (IABP), extracorporeal membrane oxygenation (ECMO) and Impella CP in the animal model of AMI complicated by VSD and cardiogenic shock. Methods Under general anesthesia and mechanical ventilation in pigs (sus scrofa domestica), using partial sternotomy, AMI was induced by ligation of left anterior descending. VSD was simulated by insertion of 25F cannulas into the left and right ventricles and their extracorporeal connection by 3/8 tubes generating left-to-right shunt. The hemodynamic effect of ECMO (2 L/min), IABP, and Impella CP (2 L/min) was evaluated by the measurement of the left ventricular end-diastolic pressure (LVEDP), mean arterial pressure (MAP), carotid flow (CAR) as a surrogate of total circulatory output, and VSD flow. Data are presented as mean (SD), P < 0.05 was considered statistically significant. Results Eleven animals were used, one died after induction of AMI, ten pigs completed all study procedures. Baseline (no mechanical support) LVEDP was 13.8 (3.0) mmHg, MAP 54.5 (11.0) mmHg, CAR 290.9 (37.3) mL/min, and VSD 1174.0 (499.3) mL/min (Table 1). IABP significantly improved all parameters in comparison to Baseline (Table 1). ECMO significantly improved MAP and CAR not only in comparison to Baseline but also in comparison to IABP and Impella; on the other hand, ECMO increased VSD flow (Table 1). Impella significantly improved all parameters with the largest effect on LVEDP and VSD flow (Table 1). Conclusions All tested devices improved the key hemodynamic parameters of MAP and CAR, however each to different extent. Individual devices influenced differently LVEDP and VSD flow. The results of this study may help in selection of optimal therapeutic strategy in AMI complicated by VSD and cardiogenic shock.Table 1.Hemodynamic outcomes.