Dr Williams noted the limited available data on the use of Impella devices during cardiac surgery. RECOVER I was a prospective pilot study of Impella 5.0/left direct for postcardiotomy cardiogenic shock (PCCS).1 The study demonstrated that safety and feasibility of the use of the Impella 5.0/left direct in PCCS with a favourable survival of 94% at 30 days. Immediately after the initiation of Impella support, cardiac index, mean arterial pressure and pulmonary artery diastolic pressure improved.
Lemaire et al. reported a single-centre study of 47 patients treated with Impella for cardiogenic shock (CS), including 32 patients with PCCS.2 Survival at 30 days was 75% and 63.8% at 1 year. Of the 35 survivors, 88% had recovery of native heart and 11% were bridged to long-term ventricular assist devices.
Dr Williams highlighted study findings suggesting early initiation of Impella support prior to percutaneous coronary intervention was associated with improved survival. This led to the hypothesis that preoperative selection of high-risk patients for placement of Impella devices to haemodynamically optimise them before surgery and assist with recovery in the immediate postoperative period should allow faster recovery, reduced intensive care unit and hospitalisation days, improved end-organ function and reduced inotropic needs immediately postoperatively.
Dr Williams tested this hypothesis at his institution, which is a community healthcare system involving two hospitals, two catheterisation laboratories and four cardiac operation theatres. The cath lab Impella programme has been available since 2014, and the surgical Impella programme started in 2017. In the surgical programme, Impella support is used in three different subsets of patients: elective insertion of Impella preoperatively, haemodynamic optimisation group receiving Impella preoperatively (patients presenting in CS receive Impella urgently to stabilise) and rescue insertion of Impella for PCCS.
The Impella device was used electively in patients based on frailty or surgeon gestalt, in addition to ejection fraction (EF) <20% and undergoing any procedure requiring cross-clamp, EF 20–30% undergoing off-pump coronary artery bypass grafting (CABG) or EF <25% undergoing major valve/CABG/double-valve procedures. Patients in the haemodynamic optimisation group receive Impella preoperatively to reverse end-organ damage, assist with diuresis and unload the ventricle while recovering from an acute event. Typical patients include those with acute MI and decompensation in need of urgent CABG and decompensated chronic heart failure with EF <25% requiring valve surgery. Impella use for PCCS was defined as ≥2 escalating doses of inotropes, inability to wean from cardiopulmonary bypass and failure to improve with an intra-aortic balloon pump.
A total of 149 patients received Impella devices at their institution. Of these, 35 patients underwent definitive surgical intervention following the initiation of Impella support; 23 patients received Impella electively, while 12 received Impella urgently. Patients receiving elective Impella support had a lower EF (19% ± 5%) compared to those receiving urgent Impella support (39% ± 17%). About 25% of patients in the elective group received high-dose inotropes, compared to 0% in the urgent group. The overall 30-day mortality was 9%, with no difference between the elective versus urgent Impella groups. The postoperative mortality was higher among patients with end-organ dysfunction, such as kidney or liver failure. There was a trend towards higher utilisation of blood products in patients receiving Impella CP versus Impella 5.0.
In conclusion, the results suggest that high-risk cardiac surgery with Impella support is safe, feasible and effective in the community hospital setting. Also, preoperative identification of high-risk patients who may benefit from left ventricular unloading with Impella is possible. Additional data might permit the development of a selection algorithm that would be broadly applicable to optimise outcomes in patients undergoing high-risk cardiac surgery.