Preemptive transvalvular mechanical circulatory support is safe and feasible in high-risk cardiac surgery patients: Results of Impella-Protected Cardiac Surgery Trial.

OBJECTIVES

To assess the safety and feasibility of Impella 5.5-protected cardiac surgery in patients with severe left ventricular dysfunction.

METHODS

Impella-Protected Cardiac Surgery Trial is a prospective, multicenter, single-arm study assessing the safety and feasibility of initiating transvalvular left ventricular unloading prior to separation from cardiopulmonary bypass. Eligible patients had a reduced left ventricular ejection fraction with planned elective or urgent conventional cardiac surgery. Patients were supported with the Impella 5.5 for at least 24 hours postoperation. Key exclusion criteria included preoperative inotropic or mechanical circulatory support. A clinical events committee adjudicated end points.

RESULTS

One hundred subjects were enrolled at 18 sites in the United States, all of whom successfully received the Impella 5.5. Baseline left ventricular ejection fraction was 25% (interquartile range [IQR], 21.6, 28.9), and Society of Thoracic Surgeons' Predicted Risk of Mortality was 4.1% (IQR, 2.5, 7.1). The index cardiac procedure was primarily isolated coronary artery bypass graft (56%) or coronary artery bypass graft + valve (35%). Post-cardiotomy cardiac failure through hospital discharge, the primary effectiveness end point, occurred in 6% of subjects. The composite of all-cause mortality, stroke, and a new requirement for renal replacement therapy through 90 days postoperation, the primary safety end point, occurred in 12% of subjects. The 30- and 90-day mortality was 2% and 4%, respectively. Subjects had a favorable postoperative trajectory with low perioperative vasoactive inotrope score (VIS) (VISmax <10 within 24 hours postoperation), timely extubation (14.4 hours), and an acceptable hospital length of stay (13.9 days).

CONCLUSIONS

Impella 5.5-protected cardiac surgery appears safe and feasible and is a promising device-supported strategy for cardiac surgery patients with severe left ventricular dysfunction.