The Impella 5.5 is an axillary mechanical circulatory support device used in patients with cardiogenic shock, but those with small left ventricular (LV) cavities may be at risk for suction events, hemolysis, malpositioning, hypoperfusion, and LV injury. Informally accepted guidelines, extrapolated from durable LVAD studies, suggest a minimum left ventricular internal dimension in diastole (LVIDd) of 58 mm, with some clinical practices using a more stringent ≤52 mm cutoff. We retrospectively analyzed 154 consecutive patients supported with Impella 5.5 between January 2020 and December 2024. Overall, 38 patients had an LVIDd ≤58 mm, and 116 had an LVIDd >58 mm; a key subgroup of 21 patients presented with a very small LVIDd of ≤52 mm]. Baseline demographics, comorbidities, body mass index, and renal function were similar [across groups], although those with larger LVIDd had lower ejection fractions (16% vs. 24%, p = 0.001). Median support duration was 24 days in all groups, and pre- and post-implant hemodynamic and laboratory improvements were comparable. Rates of transplantation (79% vs. 90%, p = 0.088) and LVAD implantation (2% vs. 6%, p = 0.159) did not differ significantly in the ≤58 mm cohort. Notably, within the ≤52 mm subgroup, 90-day survival remained high at 90.5% ( p = 0.336), with significant improvements in right atrial pressure (17 to 10 mmHg, p = 0.041), mean pulmonary artery pressure (36 to 26 mmHg, p = 0.008), and eGFR (45 to 57 mL/min/1.73m 2 , p = 0.003). Remarkably, native cardiac recovery was observed exclusively in the smaller LV cohorts, occurring in 11% of the ≤58 mm group ( p = 0.003 vs. 0%, p = 0.003) and reaching 19% in the ≤52 mm group (vs. 0% in larger cavities, p < 0.001), while durable LVAD escalation was entirely avoided in the ≤52 mm cohort (0% vs. 6%). Ninety-day event-free survival was excellent across all cohorts 92% vs. 96% in the primary analysis, with no major device-related complications, suction events, clinically significant hemolysis, bleeding, stroke, or escalation to Bi-VAD support. These findings strongly support the safety and feasibility of Impella 5.5 in extremely constrained, small LV cavities.
Mid-Term Survival in Patients Awaiting Heart and Kidney Transplantation with Impella 5.5 Support
Abstract Background 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. Methods 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. Results 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. Conclusions 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.
1530: THE ASSOCIATION OF TEMPORARY PACEMAKER SETTINGS ON ICU LENGTH OF STAY AFTER HEART TRANSPLANTATION
Abstract Background Impella is an advanced ventricular assist device frequently used as a bridge to heart transplantation. The association of Impella with increased rates of gout flares has not been studied. Our primary aim is to determine the rates of gout flares in patients on Impella support. Methodology A retrospective study was conducted between January 2017 and September 2022 involving all patients who underwent heart transplantation. The cohort was divided into groups based on Impella support for statistical analysis. In patients receiving Impella support, outcome measures were compared based on the development of gout flares. Results 213 patients were analyzed, with 19.71% supported by Impella. Impella and non-Impella groups had similar age, race, and BMI, but more males were in the Impella group. Gout and chronic kidney disease were more prevalent in Impella-supported patients, while coronary artery disease was less common. The incidence of gout flare was significantly higher in Impella patients (31% vs. 5.3%). The Impella group had an adjusted odds ratio for in-hospital gout flare of 8.069 (95% CI = 2.13–35.08, P = 0.003). Impella-supported patients with gout flares had longer intensive care unit and hospital stays but no difference in mortality or other outcomes. Conclusion Our study is the first to identify the potential association between Impella support and increased rates of gout flares in hospitalized patients. Future studies are required to confirm this association and further elucidate the biological pathways. It is imperative to consider introducing appropriate measures to prevent and promptly manage gout flares in Impella-supported patients.
P103: Impella 5.5: An Alternative Therapy for Complex Patients with WHO Class II Pulmonary Hypertension
One of the signicant obstacles to donor heart utilization is that increasingly prolonged cold ischemic times are associated with worsened short- and long-term outcomes. As a result, most transplant centers aim to limit cold ischemic times to less than four hours. The TransMedics Organ Care System (OCS) (Trans Medics, Andover MA) is a portable ex vivo perfusion system designed to store a donor heart in a beating, metabolically active state, until it reaches the recipient, thereby allowing extended time outside the body while minimizing the effects of cold storage. We present a case of a heart transplant recipient supported with the Impella 5.5 as a bridge to transplantation who received a donation after circulatory death (DCD) heart supported by OCS. To our knowledge, this is the rst report of such a case.
REN3: Percutaneous Axillary Temporary Mechanical Support Improves Renal Function Prior To Heart Transplantation In Patients With Chronic Kidney Disease