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.
Abstract P187: Comparative Analysis Of Covid-19 Vaccine Efficacy In Heart Transplant Recipients On Standardized Immunotherapy Regimens
Background: International data on COVID-19 infection in immunosuppressed populations is limited. Heart transplant (OHT) recipients requiring immunotherapy are at risk for potentially increased complications with COVID-19 infection, including long-covid and oxidative stress during initial infection. The availability of vaccination and temporal trends in this population has not been well described. We report outcomes in immunosuppressed patients during the initial years of the COVID pandemic. Methods: All patients who underwent heart transplantation at Mayo Clinic in Florida were reviewed from March 2019 to October 2021. Patients were divided into two groups: those diagnosed with COVID-19 (based on a positive SARS-CoV-2 RT-PCR) and those not. A p value of 0.05 was considered significant using the Chi-squared test. Results: A total of 98 patients were reviewed. Of these, 49 were COVID-19-positive (CP), and 49 were negative (CN). The cohort was well matched, with a median age of 58 years (49 - 65) in both groups. 20 females in the CP group and 9 in the CN group. Diabetic status (p = .07), history of hypertension (p=.5), BMI (p=.41), GFR (p=.19), and ejection fraction (p=.29) were not significantly different between the two groups. Immunosuppression was not significantly different for CP or CN patients, with a median trough tacrolimus level of 7.68 vs. 8.70 (p = .26). The median time from transplant to CP was 384 days (237 - 677). The CN group’s median follow-up after transplant was 947 days (737 - 1191). CP hospitalization rate was 24% (5 Pfizer, 3 unvaccinated, 4 Moderna) with only 1 death. Hospitalized patients’ markers of inflammation were: IL6 19.2 (12-48), D-dimer 1408 (763 - 2227), and CRP 54 (20 - 90). The CP group was more vaccinated than the CN group (92% vs. 78%, p = .025). More CP patients received the Pfizer vaccine compared to Moderna (p = .018). Conclusion: We found that patients after OHT on similar immunotherapy regimens did not carry the same risk of contracting Covid-19 despite being vaccinated. CP patients were generally infected in the first 1.5 years after OHT. This may indicate an increased infection rate due to a weakened immune system or lack of bivalent boosters before 2022. Vaccine efficacy in this population should be evaluated in larger studies.
Abstract P102: Gender-based Stroke Risk In Patients With Afib And Heart Failure Treated With Mineralocorticoid Receptor Antagonists
Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia detected in hospitalized patients. It is independently associated with an increased risk of stroke. Anti-fibrotic properties of mineralocorticoid receptor antagonists (MRA) have been proposed to modulate AF burden. Gender differences in patients with AF exist within the epidemiology and causative mechanisms to outcomes and complications. We compared men and women with known AF while treated with MRA to assess potential differences in stroke rate. Method: After IRB approval, we performed a retrospective chart review of all patients with confirmed HF and AF diagnoses. Patient data were extracted from electronic medical records. Patients with AF and HF treated with MRA were included in this study. Results: 64 patients with HF and AF treated with MRA were reviewed between January 2021 and September 2022. 34 were male, and 30 were female. Females were younger, 66 years (57 -74) compared to males, 73 years (60 - 78), p=.13. The median ejection fraction was similar among women, 42% (31 - 50) compared to men, 41% (33 - 49), p = .43. A significantly higher incidence of atrial fibrillation was found in our male group (59%) compared to the female group (30%), p=.02. There was no significant difference in MRA or anticoagulation use between male and female patients (p = .11, p = .12 respectively). More men had strokes compared to females (16% vs. 26% p = .17). Men were also more likely to be hypertensive compared to females (47% vs. 25%, p<.01). Conclusion: Men were more likely to have AF and stroke compared to females with HF on MRA therapy. Males were more likely to be hypertensive, which may relate to increased stroke rate in this patient population. Increased awareness of the gender-based prevalence of stroke rate in patients with HF and AF may allow for earlier recognition and reduction in stroke events.
P103: Impella 5.5: An Alternative Therapy for Complex Patients with WHO Class II Pulmonary Hypertension