Impella preserves haemodynamics with adequate stressed blood volume and normal pulmonary vascular resistance in a goat model of ventricular fibrillation.

AIMS: Ventricular fibrillation (VF) is a frequent and life-threatening complication of acute myocardial infarction. Although the Impella device provides circulatory support solely to the left ventricle (LV), emerging reports have suggested that it may partially maintain haemodynamics even during VF. This study sought to examine this phenomenon under controlled experimental conditions.

METHODS AND

RESULTS

In eight Saanen goats, we recorded right atrial pressure (RAP), left atrial pressure (LAP), arterial pressure (AP), LV pressure, pulmonary artery flow (PAF), carotid artery flow (CAF), and coronary flow (CoF). We inserted an Impella CP and induced VF using direct current. In Protocol 1, we changed the stressed blood volume (SBV) by blood withdrawal/infusion or pulmonary vascular resistance (PVR) by pulmonary microembolisation and measured the haemodynamics during VF with Impella P4 support (n = 1 each). In Protocol 2 (n = 6), we compared the central and peripheral blood flows between the baseline conditions and three Impella support levels (P0, P4, and P8) during VF. In Protocol 2, an increase of Impella support to P4 and P8 during VF significantly increased AP in a support level-dependent manner (P0, P4, and P8: 26.5 ± 2.5, 57.7 ± 8.7 and 72.0 ± 15.3 mmHg, respectively; P < 0.001) while lowering RAP and LAP. Impella partially maintained PAF (0, 1.2 ± 0.6 and 1.6 ± 0.9 L/min; P = 0.011), CAF (0, 177.6 ± 26.3 and 235.5 ± 44.1 mL/min; P < 0.001), and CoF (0, 68.5 ± 32.0 and 57.8 ± 20.6 mL/min; P = 0.002) during VF.

CONCLUSION

Impella preserved systemic, cerebral, and coronary blood flow with adequate SBV and normal PVR conditions in a goat model of VF.