Mid-term survival in patients awaiting heart and kidney transplantation with Impella 5.5 support

Patients with end-stage heart failure and chronic kidney disease requiring dual-organ transplantation (DOT) face significant challenges in utilizing durable mechanical circulatory support due to the risks associated with renal replacement therapies (RRTs) and multi-organ failure. Given the limited options available for long-term support in this patient population, there remains a critical need for alternative strategies to optimize end-organ function and bridge patients safely to transplant. With prolonged waitlist times for DOT, we present our experience with the Impella 5.5 as temporary mechanical circulatory support, demonstrating its potential to provide hemodynamic stability and support as a bridge to transplantation (BTT) in this complex cohort.

A single-centre retrospective review was completed of all patients listed for single-organ transplantation or DOT between December 2019 and November 2022 at Mayo Clinic in Florida, supported by the Impella 5.5 intended as BTT. The focus of this analysis was patients requiring RRT or listed for heart/kidney transplantation. Data were extracted from the electronic health record at baseline and during their transplant episode of care after institutional review board approval as exempt status for retrospective data collection.

A total of 41 patients were supported with Impella 5.5, intended as BTT. All patients underwent successful transplantation. We focus on the 10 patients with Impella support who underwent DOT. In the DOT group, the median age at transplantation was 63 years (59-66), with nine males and one female. The baseline median ejection fraction was 19% (15-22), with 50% Caucasian and 50% African American and an even split between ischaemic and non-ischaemic aetiology. Median body mass index was 30 kg/m² (26-31), and 60% were in blood group O. The median time on the waitlist for DOT patients was 53 days (29-75). Perioperative management of DOT Impella patients demonstrated baseline haemodynamics of RA 11 mmHg (7-16), mean PA 36 mmHg (32-47), PCWP 29 mmHg (21-35), mixed venous saturation (SVO₂%) 51 (46-61) and Fick CI 2.03 L/min/m² (1.66-2.5). Post-Impella placement haemodynamics demonstrated significant improvements in RA pressure to 5 mmHg (4-8), P = 0.02, SVO₂ to 70% (65-72), P = 0.002, and Fick CI to 5.5 (5.2-8), P = 0.03. The average duration of support was 44 days (range 10-94). The median glomerular filtration rate at baseline was 27 mmol/L (16-29). Twenty-four hour urine protein averaged 168 mg/24 h (range 87-328), with the 24 h creatinine clearance of 29 mg/24 h (range 24-35). Eight of the 10 patients required continuous or intermittent RRT before DOT. The median total duration of RRT (including Impella support) was 36 days (9-72). DOT recipients had a 1 year survival of 90%, with an average follow-up of 432 days.

Our findings demonstrate that prolonged use of the Impella 5.5 provides safe and effective haemodynamic support for patients with end-stage heart and kidney failure awaiting dual-organ transplantation. With a 1 year survival rate of 90%, our data suggest that Impella 5.5 can be a viable alternative to traditional support strategies, particularly in patients who are otherwise limited by RRTs. As dual-organ transplantation becomes more prevalent, the Impella 5.5 offers a promising bridge to transplant, improving both short-term and long-term outcomes in this complex patient population.