Outcomes following coronary artery bypass grafting with temporary left ventricular assist device support

The Impella 5.5 is a temporary mechanical circulatory support device consisting of a microaxial pump that unloads the left ventricle and provides hemodynamic support, but data in bypass grafting (CABG) are limited.

We conducted a single-center retrospective case series of adult patients who underwent isolated CABG with perioperative Impella 5.5 support between July 2020 and May 2024. Perioperative support was defined as implantation before separation from cardiopulmonary bypass (CPB) or immediately after CPB wean. Patients with prior mechanical circulatory support, preoperative Impella as the primary indication, or concomitant/reoperative cardiac surgery were excluded. Clinical characteristics, procedural details, and early outcomes were obtained from the electronic medical record.

Sixteen patients met inclusion criteria. Median age was 59 years (range: 51-90 years), 93.8% were male, and 75.0% self-identified as White. Median preoperative LVEF was 20.5% (IQR: 15-25). Median Impella support duration was 6.97 days (IQR: 3.7-20.3 days). The device was implanted before CPB separation in 8 patients (50.0%) and immediately after CPB wean in 8 (50.0%); 93.8% were implanted via a right axillary graft. Thirteen patients (81.3%) were successfully weaned, and 1 patient (6.3%) was bridged to HeartMate 3. Two patients (12.5%) died before device explantation, and 1 additional patient died later during the same hospitalization after explantation, yielding an overall in-hospital mortality of 3 patients (18.8%). Rhythm complications occurred in 9 patients (56.3%), most commonly rapid atrial fibrillation (31.3%); sustained ventricular tachycardia occurred in 2 (12.5%), with 1 death. One intrapump thrombus required device exchange; no major bleeding or access-site infections occurred.

Impella 5.5 support in high-risk CABG with LV dysfunction was feasible in selected patients and may serve as an adjunct to surgical revascularization.