Safety and usefulness of left ventricular endomyocardial biopsy in new- onset acute heart failure requiring mechanical support by an Impella® device

Background: In patients with de novo acute heart failure (AHF) requiring veno-arterial extracorporeal membrane oxygenation (VA-ECMO), endomyocardial biopsy (EMB) has been recently shown to be feasible and a helpful method to clarify differential diagnoses, including acute myocarditis. This study aimed to evaluate the feasibility and safety of EMB in patients with a left ventricular (LV) implanted Impella® device.

Methods and results: This retrospective, single-center study involves 22 cardiogenic shock patients [SCAI shock stage: C (91%)] requiring mechanical circulatory support (MCS) either by Impella® axial pumps [20 patients (91%)] alone or in combination with VA-ECMO [2 patients (9%)] between December 2017 and January 2022. Coronary artery disease (CAD) or severe valvular heart disease were excluded. The study's primary endpoint was to verify the safety of EMB during MCS. Furthermore, histopathological analysis of the EMB samples was described. 30 LV-EMB procedures were performed. No major complications were reported (death, sustained ventricular tachycardia, need for cardiopulmonary resuscitation, cardiac tamponade, stroke, major bleeding). In 14 patients (64%), EMB-derived histology/immunohistology led to the definitive diagnosis of acute myocarditis.

Conclusions: EMB can be safely performed in patients suffering from cardiogenic shock requiring an Impella®-based MCS without the risk of major complications. In about 50% of the patients, relevant inflammatory heart disease could be detected, which required a change in treatment decisions.