Cardiac allograft vasculopathy (CAV) remains a leading cause of graft failure after heart transplantation, yet an early, non-invasive risk stratification tool is not available. Artificial intelligence electrocardiography (AI-ECG) can estimate biological heart age, and it has been associated with cardiovascular risk. Its deviation with chronological age, called delta age, and its utility in the prediction of CAV has never been explored. We conducted a retrospective single-center study for heart transplant recipients bridged with Impella 5.5 (Abiomed, Danvers, MA, USA) at Mayo Clinic Florida (2020–2023). ΔAge was calculated at discharge and 1-year post-transplant. The primary outcome was confirmed CAV at 1 year. Univariate and multivariable logistic regression models were used to assess the independent association between the ΔAge and the development of CAV, with discrimination evaluated by AUC and internally validated via bootstrap resampling (2000 iterations). Fifty patients were reviewed. CAV developed in 13 (26%) patients in 3 years. CAV+ patients had a significantly higher ΔAge at discharge compared to CAV- patients (median −1.0 vs. −11.0 years, p = 0.0023) and at 1 year (median +7.0 vs. −4.0 years, p = 0.0080). On univariate analysis, ΔAge at discharge was a significant predictor of the development of CAV (OR 1.084 per year, AUC 0.788). On multivariable adjustment, ΔAge at discharge remained an independent predictor (adjusted OR 1.138, 95% CI 1.023–1.265, p = 0.018, and model AUC 0.859). ΔAge at discharge is a novel and potential predictor of the development of CAV within 3 years. These findings support the integration of AI-ECG into post-transplant surveillance as a scalable, low-cost tool.
Time Is Key: Early Diagnosis of Post-Transplant Lymphoproliferative Disorder Presenting as Primary CNS Diffuse Large B-Cell Lymphoma
Post-transplant lymphoproliferative disorder (PTLD) involving the central nervous system (CNS) is a rare but serious life-threatening complication seen in recipients of solid organ transplant. Primary CNS encompasses 5–15% of all types of PTLD diagnoses, and heart transplant recipients represent 3–5% of those reported cases. Diagnosis is often delayed due to the highly variable presentation, with some cases remaining undiagnosed for years. Multidisciplinary collaboration is crucial for early diagnosis and management. A 53-year-old woman patient presented with altered mental status. MRI revealed nodular ventriculitis and bilateral periventricular hyperdense infiltrates. CSF studies demonstrated lymphocytic pleocytosis, elevated protein, and EBV-PCR-positive results. A stereotactic brain needle biopsy confirmed the presence of EBV-positive diffuse large B-cell lymphoma, consistent with primary CNS PTLD, 14 months after her heart transplant. Despite appropriate management, the patient experienced progressive neurological decline and ultimately suffered a fatal intracerebral hemorrhage. We demonstrate the importance of the early diagnosis and variable presentation of post-heart-transplant PTLD. The importance of surveillance regardless of EBV status and close monitoring of disease progression due to potential life-threatening complications, such as fatal hemorrhages. Therefore, primary CNS-PTLD remains a challenging disease and is being increasingly recognized with improved transplant recipient survival and prolonged exposure to chronic immunosuppression.
Engineering the Future of Heart Failure Therapeutics: Integrating 3D Printing, Silicone Molding, and Translational Development for Implantable Cardiac Devices
Three-dimensional (3D) anatomic modeling derived from high-resolution medical imaging, such as computed tomography (CT) and magnetic resonance imaging (MRI), has been increasingly adopted in preclinical testing and device development. This white paper describes a cardiac-specific workflow that integrates 3D printing and silicone molding for support device development and procedural simulation. Patient-derived computed tomography angiography data were segmented using FDA-cleared medical modeling software to isolate the left ventricular anatomy and were further processed in computer-aided design (CAD) to ensure accurate physiological wall thickness and structural fidelity. Material jetting 3D printing was performed on a Stratasys J750 using material distributions designed to mimic the mechanical properties of myocardium, thereby approximating myocardial compliance. In parallel, stereolithography apparatus molds were designed from the left ventricle CAD model to cast transparent, pliable left ventricular models in Sorta-Clear™ 18 silicone. The 3D-printed models preserved intricate morphological detail and were suitable for mechanical manipulation and device deployment studies, whereas silicone models offered tunable mechanical properties, transparency for visualization, and durability for repeated use. Together, these complementary modalities provided rapid manufacturing capability and application-relevant physical representation. Case-specific parameters, strengths, and limitations of both models in enhancing patient care and device testing are highlighted, with relevance to heart failure applications. Current knowledge gaps, workflow and integration challenges, and future opportunities are identified, positioning this work as a reference framework for continued innovation in anatomic modeling. Within the collaborative framework of Mayo Clinic’s Anatomic Modeling Unit and Simulation Center, this integrated modeling workflow demonstrates the value of multidisciplinary collaboration between engineers and clinicians. Clinically, these patient-specific left ventricular models may enable pre-procedural device sizing and positioning and may support simulation of mechanical circulatory support (MCS) deployment while identifying possible anatomic constraints prior to intervention. This workflow has direct applicability in advanced heart failure patients undergoing MCS support, such as the Impella axillary MCS device or the durable LVAD, with potential to reduce procedural uncertainty while reducing complications and improving peri-procedural outcomes. Additionally, these models also serve as high-accuracy educational tools, enabling trainees and multidisciplinary care teams to visualize and possibly rehearse procedural steps while gaining hands-on experience in a risk-free environment.
Percutaneous Temporary Mechanical Circulatory Support as a Bridge to Heart Transplantation in the Current UNOS Allocation System
Background: Progressive heart failure cardiogenic shock (HFCS) often requires escalation to temporary or durable mechanical circulatory support (MCS) as a bridge to transplant (BTT). Following the 2018 UNOS allocation changes, our center revised its BTT strategy to optimize support and shorten wait times. At our institution, the Impella 5.5 with SmartAssist via the axillary approach was selectively used for patients who remained refractory to guideline-directed medical therapy, failed single-inotrope therapy, and were not considered suitable durable LVAD candidates by our multidisciplinary heart team. We compared transplant-related outcomes of BTT patients supported with Impella 5.5 versus durable LVAD. Methods: We performed a single-center retrospective review of all heart and heart/kidney transplant candidates at Mayo Clinic Florida from October 2018 to February 2021. INTERMACS profile, baseline characteristics, and perioperative data were collected at the time of device implantation and throughout the transplant hospitalization. Results: A total of 87 heart and 4 heart–kidney transplants were completed. Forty-five patients (49%) required MCS as BTT: 27 (60%) with a durable LVAD and 18 (40%) with an Impella 5.5. All eighteen patients with Impella 5.5 as BTT (100%) were transplanted compared to nineteen patients with durable LVAD (70%), p = 0.001. The median time from listing to transplant was substantially shorter with Impella (32 vs. 696 days, p < 0.001), and this difference persisted across INTERMACS profiles. UNOS status at transplant was more urgent for Impella than LVAD (p < 0.001). Transplant surgery following Impella support required shorter cardiopulmonary bypass time (181 vs. 219 min, p < 0.001) and resulted in lower postoperative vasoactive-inotropic requirements (7.9 vs. 13, p = 0.003). No patients in the Impella group died or were delisted while awaiting transplant, whereas 5 LVAD patients (26%) died or were removed due to LVAD complications (p < 0.001). Conclusions: Our data demonstrates that the use of the Impella 5.5 as BTT was associated with significantly shorter waitlist time, higher transplantation rates, reduced perioperative morbidity, and lower postoperative vasoactive support compared with durable LVAD as BTT. These benefits were achieved despite a higher severity of illness at transplantation in the Impella cohort.
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.
Empowering Early Recovery: The Role of Impella 5.5 in Takotsubo Cardiomyopathy Complicated by Cardiogenic Shock
Introduction: Takotsubo cardiomyopathy (TCM), also known as stress cardiomyopathy or Broken Heart Syndrome, is a reversible, transient state of myocardial dyskinesis and apical ballooning. Infrequently, TCM may progress to severe life-threatening complications such as cardiogenic shock. Early mechanical circulatory support (MCS) is crucial to myocardial recovery in these cases. We present one of the first cases of TCM successfully treated with the advanced micro-axial minimally invasive Impella 5.5 with SmartAssist MCS device. Case Presentation: A female in her late 70s with a history of hypothyroidism, atrial fibrillation post-ablation, and cholelithiasis was referred to our facility for an elective cholecystectomy. Post-anesthesia induction with propofol 2.1 mg/kg (140 mg bolus), she became bradycardic and hypotensive, eventually leading to asystole, requiring CPR and termination of the procedure. Echocardiography revealed a left ventricular ejection fraction (LVEF) of 24% with mid-ventricular akinesis and apical ballooning with mild mitral regurgitation, suggesting the diagnosis of TCM. Cardiac catheterization showed RA 20 and mean PA 42 mmHg. Lactate was 18.7 mmol/L and LDH 1776 U/L, suggesting progressive shock. Continuous epinephrine 0.1 mcg/kg/min and norepinephrine 0.06 mcg/kg/min were titrated for BP 97/58, and she was initially supported with the Impella CP device. Despite aggressive efforts, rising LDH levels and increased vasopressor needs indicated inadequate organ perfusion, requiring an upgrade to Impella 5.5. Impella 5.5 support for 11 days led to impressive myocardial recovery, leading to reductions, and eventual discontinuation, of inotropes and vasopressors. Post-Impella 5.5 explantation, her LVEF was 59–65% and she was discharged with Mobile Cardiac Outpatient Telemetry (MCOT) monitoring for her arrhythmias and reinitiation of guideline-directed medical therapies (GDMTs) for her comorbidities. Her 2-month follow-up shows sustained LVEF greater than 45% with functional improvements. Conclusions: Early escalation within 24 h of Impella CP to Impella 5.5 provided stabilization of cardiometabolic shock, preventing end-organ damage, allowing recovery of native heart function while maintaining ambulatory status, and allowing for optimizing medical therapy. It presents a safe, minimally invasive, and cost-effective intervention in TCM cases refractory to GDMT or when additional time is needed for decision-making in cases presenting with CS.
Right Atrial Thrombus Complicating LVAD Candidacy: A Clinical Case Study
Background: Right atrial thrombus (RAT), though rare, carries a high risk of pulmonary or systemic embolism and a 25–44% mortality rate. In LVAD candidates, coexisting RAT significantly complicates perioperative management due to their critical condition and high risk of decompensation during surgery. Percutaneous thrombectomy offers a less invasive, lower-risk alternative to open surgery, enabling faster recovery. Case Presentation: We present a case of a 76-year-old male with ischemic cardiomyopathy and heart failure secondary to Adriamycin chemotherapy with an ejection fraction (EF) of 26%, diabetes mellitus, and stage 3 chronic kidney disease, scheduled for left ventricular assist device (LVAD) implantation. Preoperative echocardiography revealed a large, multilobulated, mobile thrombus in the right atrium. Given the high surgical risk and thrombus mobility, percutaneous thrombectomy using the AngioVac system (Angiodynamics, Latham, NY, USA) was performed. The thrombus was successfully removed, and the patient was discharged on apixaban for long-term anticoagulation. Advanced medical therapy and transplant/durable LVAD evaluation were delayed by 35 days to allow for the stabilization of any postoperative effects. Conclusions: This case underscores the efficacy of percutaneous thrombectomy as a bridge to LVAD in high-risk patients, reducing thromboembolic complications and supporting safe LVAD implantation.
Health-Related Quality-of-Life Measures in Patients with Heart Failure Cardiogenic Shock Following Axillary Mechanical Circulatory Support
Background: Patients with end-stage heart failure-related cardiogenic shock (HF-CS) are conclusively associated with a poor health-related quality of life (HRQL). Axillary mechanical circulatory support (aMCS), such as the Impella 5.5, is increasingly used in this population and may improve HRQL during hospitalization by providing enhanced left ventricular unloading. We aimed to assess changes in HRQL between admission and two weeks after Impella 5.5 placement in patients with HF-CS, using the Kansas City Cardiomyopathy Questionnaire (KCCQ). Methods: We conducted a prospective longitudinal analysis on patients with the Impella 5.5 between May 2023 and July 2023. Participants completed the condensed KCCQ-12 at admission and again two weeks post-implantation. Changes in the scores were evaluated using the Wilcoxon signed-rank test. Results: Fifteen patients were enrolled. The median age was 59 years (50–63), and the median ejection fraction at implantation was 20% (15–30). On admission, most patients reported an overall HRQL of poor-to-fair (46.7%) according to the summary KCCQ-12 score. The median overall summary score increased significantly after Impella 5.5 support (50.52 vs. 28.13, p = 0.005). Symptom frequency (70.83 vs. 43.75, p = 0.009) and quality-of-life (50.00 vs. 12.50, p = 0.023) domains improved significantly, while physical limitation showed a positive trend and social limitation remained unchanged. These HRQL improvements occurred alongside a significant shift toward lower SCAI shock stages, marked increases in cardiac output and cardiac index, and no escalation in vasoactive-inotropic requirements. Conclusions: Impella 5.5 support in HF-CS patients was associated with early and clinically meaningful improvements in HRQL, particularly in symptom frequency and quality of life, during the critical pre-transplant or recovery period. These findings suggest that the Impella 5.5 may provide both physiological and patient-perceived benefits in this high-risk population.
Recognizing Post-Cardiac Injury Syndrome After Impella 5.5 Insertion in Cardiogenic Shock: A Case-Based Discussion
The use of temporary mechanical circulatory support in refractory heart failure cardiogenic shock (HFCS) has risen, leading to potential complications. Post-Cardiac Injury Syndrome (PCIS) from Impella insertion is rare but may result from subclavian artery manipulation and aortic irritation. We report the first case of pericarditis (PCIS) caused by Impella 5.5 insertion in an HFCS patient awaiting heart transplantation. The patient developed chest pain, tachycardia, and hypotension post-Impella insertion. Laboratory results and electrocardiograms confirmed PCIS. Treatment with Ibuprofen and Colchicine was successful. He received a heart transplant 14 days later. This case emphasizes recognizing iatrogenic pericarditis after Impella insertion and the need to avoid additional myocardial strain.
A Rare Coexistence of Klippel–Trenaunay Syndrome and Cardiac Sarcoidosis
Klippel–Trenaunay (KT) syndrome and Cardiac Sarcoidosis (CS) are two distinct medical conditions that rarely coexist, each presenting unique challenges in diagnosis and management. Here, we present a rare case of a 30-year-old male with a history of KT syndrome complicated by recurrent deep vein thrombosis, who presented with symptoms of acute heart failure including shortness of breath, fatigue, dizziness, palpitations, and chest pain and was subsequently diagnosed with isolated CS. We discuss the importance of thorough clinical evaluation and multimodal diagnostic approaches in this complex scenario with overlapping symptoms and diagnostic dilemmas.