CARC3: Simultaneous Transvalvular Percutaneous Left Ventricular Assist Device (LVAD) Exchange: A Reliable Method for Uninterrupted Mechanical Circulatory Support

Abstract

Background: Impella CP and Impella 5.5 are commonly used catheter-based percutaneous transvalvular LVADs with differing flow support capacities and sites of placement. Impella exchanges are indicated for escalation of therapy, in cases of vascular or renal complications, and for mobility enhancement and improvement of physical conditioning. During conventional exchange, flow interruption occurs as the old device is pulled into the thoracic aorta prior to advancing the new device into the left ventricle (LV), threatening hemodynamic collapse in device-dependent cardiogenic shock patients. While “double device” uninterrupted Impella exchange has been reported, concerns remain with respect to valve damage, stroke, and entanglement with two devices concurrently in the LV. We present the largest institutional experience of simultaneous transvalvular Impella placement reported to date, demonstrating the feasibility, reproducibility and safety of the uninterrupted percutaneous LVAD exchange. Methods: 22 consecutive cardiogenic shock patients supported by an Impella (CP, 5.0 or 5.5) and requiring LVAD device replacement underwent a simultaneous transvalvular exchange procedure. The new device was advanced into the LV under transesophageal echocardiographic (TEE) and fluoroscopic guidance with the old device still in position. Flow was started on the new device as the old device was weaned, powered down and removed from the ventricle. Demographic data, etiology of illness, indication for device exchange, details of that exchange, and any postoperative complications were analyzed. Results: 95.5% (21/22) of patients were male, with average age of 54 years (32-71). 68.2% (15/22) had ischemic, whereas 31.8% (7/22) had nonischemic cardiomyopathy. Initial Impella location was the femoral artery in 90.9% (20/22) of patients. Replacement device was inserted via the right axillary artery in 90.9% (20/22) of patients. Using intraoperative TEE, 95.5% (21/22) showed no postoperative aortic insufficiency (AI), whereas 4.5% (1/22) had trace AI. No patients suffered vascular complications or suffered cardiac arrest during device exchange. One patient (4.5%) developed a hemorrhagic stroke 3 days post exchange. 59.1% (13/22) survived, with 3 patients recovering, 8 progressing to heart transplant, and 2 to durable LVAD. The ECMO-Impella patients had a survival rate of 35.7% (5/14), while the Impella-only survival was 100% (8/8). Conclusion: Based on our institutional experience, this technique is safe and reliable for escalating percutaneous LVAD device support in patients who are critically ill and cannot tolerate flow interruption. The severity of illness in this cohort is reflected in the incidence of pre-existing end-organ injury and overall mortality. By our evaluation, this “double barrel” exchange technique carries a significant advantage and minimal risk; however, larger studies will be needed to demonstrate statistical equivalency of this approach.Figure 1. Fluoroscopy demonstrating both percutaneous LVAD devices within the LV simultaneouslyFigure 2. Simultaneous Transvalvular Percutaneous LVAD Exchange