18F-FDG PET/CT in left ventricular assist device infections: In-depth characterization and clinical implications.

BACKGROUND: Previous retrospective studies suggest a good diagnostic performance of 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET)/computed tomography (CT) in left ventricular assist device (LVAD) infections. Our aim was to prospectively evaluate the role of PET/CT in the characterization and impact on clinical management of LVAD infections. METHODS: A total of 40 patients (aged 58 [53-62] years) with suspected LVAD infection and 5 controls (aged 69 [64-71] years) underwent 18F-FDG-PET/CT. Four LVAD components were evaluated: exit site and subcutaneous driveline (peripheral), pump pocket, and outflow graft. The location with maximal uptake was considered the presumed site of infection. Infection was confirmed by positive culture (exit site or blood) and/or surgical findings. RESULTS: Visual uptake was present in 40 patients (100%) in the infection group vs 4 (80%) control subjects. For each individual component, the presence of uptake was more frequent in the infection than in the control group. The location of maximal uptake was most frequently the pump pocket (48%) in the infection group and the peripheral components (75%) in the control group. Maximum standard uptake values (SUVmax) were higher in the infection than in the control group: SUVmax (average all components): 6.9 (5.1-8.5) vs 3.8 (3.7-4.3), p = 0.002; SUVmax (location of maximal uptake): 10.6 ± 4.0 vs 5.4 ± 1.9, p = 0.01. Pump pocket infections were more frequent in patients with bacteremia than without bacteremia (79% vs 31%, p = 0.011). Pseudomonas (32%) and methicillin-susceptible Staphylococcus aureus (29%) were the most frequent pathogens and were associated with pump pocket infections, while Staphylococcus epidermis (11%) was associated with peripheral infections. PET/CT affected the clinical management of 83% of patients with infection, resulting in surgical debridement (8%), pump exchange (13%), and upgrade in the transplant listing status (10%), leading to 8% of urgent transplants. CONCLUSIONS: 18F-FDG-PET/CT enables the diagnosis and characterization of the extent of LVAD infections, which can significantly affect the clinical management of these patients.

The Cardiac Amyloidosis Registry Study (CARS): Rationale, Design and Methodology.

BACKGROUND: CARS (Cardiac Amyloidosis Registry Study) is a multicenter registry established in 2019 that includes patients with transthyretin (ATTR, wild-type and variant) and light chain (AL) cardiac amyloidosis (CA) evaluated at major amyloidosis centers between 1997 and 2025. CARS aims to describe the natural history of CA with attention to clinical and diagnostic variables at the time of diagnosis, real-world treatment patterns, and associated outcomes of patients in a diverse cohort that is more representative of the at-risk population than that described in CA clinical trials. METHODS AND RESULTS: This article describes the design and methodology of CARS, including procedures for data collection and preliminary results. As of February 2023, 20 centers in the United States enrolled 1415 patients, including 1155 (82%) with ATTR and 260 (18%) with AL CA. Among those with ATTR, wild-type is the most common ATTR (71%), and most of the 305 patients with variant ATTR have the p.V142I mutation (68%). A quarter of the total population identifies as Black. More individuals with AL are female (39%) compared to those with ATTR (13%). CONCLUSIONS: CARS will answer crucial clinical questions about CA natural history and permit comparison of different therapeutics not possible through current clinical trials. Future international collaboration will further strengthen the validity of observations of this increasingly recognized condition.

Dapagliflozin and diuretic utilization in heart failure with mildly reduced or preserved ejection fraction: the DELIVER trial.

AIMS: Dapagliflozin reduced the combined risk of worsening heart failure or cardiovascular death among patients with heart failure with mildly reduced or preserved ejection fraction. In this study, the safety and efficacy of dapagliflozin according to background diuretic therapy and the influence of dapagliflozin on longitudinal diuretic use were evaluated. METHODS AND RESULTS: In this pre-specified analysis of the Dapagliflozin Evaluation to Improve the LIVEs of Patients With Preserved Ejection Fraction Heart Failure (DELIVER) trial, the effects of dapagliflozin vs. placebo were assessed in the following subgroups: no diuretic, non-loop diuretic, and loop diuretic furosemide equivalent doses of <40, 40, and >40 mg, respectively. Of the 6263 randomized patients, 683 (10.9%) were on no diuretic, 769 (12.3%) were on a non-loop diuretic, and 4811 (76.8%) were on a loop diuretic at baseline. Treatment benefits of dapagliflozin on the primary composite outcome were consistent by diuretic use categories (Pinteraction = 0.64) or loop diuretic dose (Pinteraction = 0.57). Serious adverse events were similar between dapagliflozin and placebo arms, irrespective of diuretic use or dosing. Dapagliflozin reduced new initiation of loop diuretics by 32% [hazard ratio (HR) 0.68; 95% confidence interval (CI): 0.55-0.84, P < 0.001] but did not influence discontinuations/disruptions (HR 0.98; 95% CI: 0.86-1.13, P = 0.83) in follow-up. First sustained loop diuretic dose increases were less frequent, and sustained dose decreases were more frequent in patients treated with dapagliflozin: net difference of -6.5% (95% CI: -9.4 to -3.6; P < 0.001). The mean dose of loop diuretic increased over time in the placebo arm, a longitudinal increase that was significantly attenuated with treatment with dapagliflozin (placebo-corrected treatment effect of -2.5 mg/year; 95% CI: -1.5, -3.7, P < 0.001). CONCLUSION: In patients with heart failure with mildly reduced or preserved ejection fraction, the clinical benefits of dapagliflozin relative to placebo were consistent across a wide range of diuretic categories and doses with a similar safety profile. Treatment with dapagliflozin significantly reduced new loop diuretic requirement over time.

Impact of assuming a circular orifice on flow error through elliptical regurgitant orifices: computational fluid dynamics and in vitro analysis of proximal flow convergence.

Grounded in hydrodynamic theory, proximal isovelocity surface area (PISA) is a simplistic and practical technique widely used to quantify valvular regurgitation flow. PISA provides a relatively reasonable, though slightly underestimated flow rate for circular orifices. However, for elliptical orifices frequently seen in functional mitral regurgitation, PISA underestimates the flow rate. Based on data obtained with computational fluid dynamics (CFD) and in vitro experiments using systematically varied orifice parameters, we hypothesized that flow rate underestimation for elliptical orifices by PISA is predictable and within a clinically acceptable range. We performed 45 CFD simulations with varying orifice areas 0.1, 0.3 and 0.5 cm2, orifice aspect ratios 1:1, 2:1, 3:1, 5:1, and 10:1, and peak velocities (Vmax) 400, 500 and 600 cm/s. The ratio of computed effective regurgitant orifice area to true effective area (EROAC/EROA) against the ratio of aliasing velocity to peak velocity (VA/Vmax) was analyzed for orifice shape impact. Validation was conducted with in vitro imaging in round and 3:1 elliptical orifices. Plotting EROAC/EROA against VA/Vmax revealed marginal flow underestimation with 2:1 and 3:1 elliptical axis ratios against a circular orifice (< 10% for 8% VA/Vmax), rising to ≤ 35% for 10:1 ratio. In vitro modeling confirmed CFD findings; there was a 8.3% elliptical EROA underestimation compared to the circular orifice estimate. PISA quantification for regurgitant flow through elliptical orifices produces predictable, but generally small, underestimation deemed clinically acceptable for most regurgitant orifices.

Endovascular ablation of the right greater splanchnic nerve in heart failure with preserved ejection fraction: early results of the REBALANCE-HF trial roll-in cohort.

AIMS: In heart failure (HF) with preserved ejection fraction (HFpEF), excessive redistribution of blood volume into the central circulation leads to elevations of intracardiac pressures with exercise limitations. Splanchnic ablation for volume management (SAVM) has been proposed as a therapeutic intervention. Here we present preliminary safety and efficacy data from the initial roll-in cohort of the REBALANCE-HF trial. METHODS AND RESULTS: The open-label (roll-in) arm of REBALANCE-HF will enrol up to 30 patients, followed by the randomized, sham-controlled portion of the trial (up to 80 additional patients). Patients with HF, left ventricular ejection fraction (LVEF) ≥50%, and invasive peak exercise pulmonary capillary wedge pressure (PCWP) ≥25 mmHg underwent SAVM. Baseline and follow-up assessments included resting and exercise PCWP, New York Heart Association (NYHA) class, Kansas City Cardiomyopathy Questionnaire (KCCQ), 6-min walk test, and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Efficacy and safety were assessed at 1 and 3 months. Here we report on the first 18 patients with HFpEF that have been enrolled into the roll-in, open-label arm of the study across nine centres; 14 (78%) female; 16 (89%) in NYHA class III; and median (interquartile range) age 75.2 (68.4-81) years, LVEF 61.0 (56.0-63.2)%, and average (standard deviation) 20 W exercise PCWP 36.4 (±8.6) mmHg. All 18 patients were successfully treated. Three non-serious moderate device/procedure-related adverse events were reported. At 1-month, the mean PCWP at 20 W exercise decreased from 36.4 (±8.6) to 28.9 (±7.8) mmHg (p < 0.01), NYHA class improved by at least one class in 33% of patients (p = 0.02) and KCCQ score improved by 22.1 points (95% confidence interval 9.4-34.2) (p < 0.01). CONCLUSION: The preliminary open-label results from the multicentre REBALANCE-HF roll-in cohort support the safety and efficacy of SAVM in HFpEF. The findings require confirmation in the ongoing randomized, sham-controlled portion of the trial.

De novo human leukocyte antigen allosensitization patterns in patients bridged to heart transplantation using left ventricular assist devices.

INTRODUCTION: We examined the impact and time course of de novo human leukocyte antigen (HLA) allosensitization following left ventricular assist device (LVAD) implantation. METHODS AND RESULTS: Forty patients had a calculated panel reactive antibody (cPRA) prior to LVAD surgery between January 2014 and December 2018. Of these patients, we retrospectively studied 33 patients who had pre-LVAD cPRA <10%. De novo allosensitization was defined as cPRA ≥10% within 3 months following LVAD surgery, and "persistent allosensitization" was defined as cPRA ≥10% at time of heart transplant or death. One-third (11/33) of our cohort developed de novo allosensitization within 3-months post-LVAD. Median duration of follow-up during LVAD support was 588 days (IQR 337-1071 days), or approximately 19 months. In an adjusted, multivariable analysis, female sex remained associated with de novo allosensitization (adjusted odds ratio [95%CI]: 11 (1.4-85), P = 0.026). De novo allosensitization was subsequently associated with persistent allosensitization (P = 0.024). Both axial-flow and centrifugal-flow LVADs had similar rates of allosensitization. Compared to those with no allosensitization, patients with de novo allosensitization did not appear to have inferior post-transplant outcomes of death or treated rejection. CONCLUSION: In our single-center experience, one-third of patients developed de novo allosensitization which did not appear to associate with inferior post-transplant outcomes. Female sex was associated with de novo allosensitization.

Challenges and the innovations in the care of advanced heart failure patients during COVID-19.

The COVID-19 pandemic underscored our healthcare system's unpreparedness to manage an unprecedented pandemic. Heart failure (HF) physicians from 14 different academic and private practice centers share their systems' challenges and innovations to care for patients with HF, heart transplantation, and patients on LVAD support during the COVID-19 pandemic. We discuss measures implemented to alleviate the fear in seeking care, ensure continued optimization of guideline directed medical therapy (GDMT), manage the heart transplant waiting list, continue essential outpatient monitoring of anticoagulation in LVAD patients and surveillance testing post-heart transplant, and prevent physician burnout. This collaborative work can build a foundation for better preparation in the face of future challenges.

Safety and effects of SGLT-2 inhibitor use among LVAD patients with type 2 diabetes mellitus.

SGLT-2 inhibitors have been shown to confer reduced risk of adverse cardiovascular events in patients with heart failure, and have also been studied preliminarily among heart transplant patients, with overall positive findings. Use of SGLT-2 inhibitors among patients with durable mechanical circulatory support has not been studied. Here we present our results from a combined retrospective cohort of LVAD patients on SGLT-2 inhibitors at two major academic centers, which showed a good safety profile but prompted questions for further investigation. We advocate for further research into the safety and impact of SGLT-2 inhibitors among LVAD patients.

Guillain-Barré Syndrome After Primary Cytomegalovirus Infection in a Patient With a Heart Transplant.

A 56-year-old man underwent cardiac transplantation in April 2018. His post-operative course was uncomplicated and he had normal allograft function. On December 2019 he was admitted for fever and diarrhea and was found to have cytomegalovirus infection. A few weeks later, he presented with Guillain-Barré Syndrome. (Level of Difficulty: Advanced.).

Troubleshooting Total Artificial Heart: Novel Use of Implantable Hemodynamic Monitor.

Accurate device optimization of the Syncardia temporary total artificial heart is difficult while waiting for heart transplantation. In this challenging clinical cohort, using an implantable hemodynamic monitor (CardioMEMS HF system) can assist in volume and hemodynamic assessments. (Level of Difficulty: Advanced.).

Early use of remote dielectric sensing after hospitalization to reduce heart failure readmissions.

AIMS: Readmission after hospitalization for acute decompensated heart failure (HF) remains a major public health problem. Use of remote dielectric sensing (ReDS) to measure lung water volume allows for an objective assessment of volume status and may guide medical optimization for HF. We hypothesized that the use of ReDS would lower 30 day readmission in patients referred to rapid follow-up (RFU) clinic after HF discharge. METHODS AND RESULTS: We conducted a retrospective analysis of the use of ReDS for patients scheduled for RFU within 10 days post-discharge for HF at Mount Sinai Hospital between 1 July 2017 and 31 July 2018. Diuretics were adjusted using a pre-specified algorithm. The association between use of ReDS and 30 day readmission was evaluated. A total of 220 patients were included. Mean age was 62.9 ± 14.7 years, and 36.4% were female. ReDS was performed in 80 (36.4%) and led to medication adjustment in 52 (65%). Use of ReDS was associated with a lower rate of 30 day cardiovascular readmission [2.6% vs. 11.8%, hazard ratio (HR): 0.21; 95% confidence interval (CI): 0.05-0.89; P = 0.04] and a trend towards lower all-cause readmission (6.5% vs. 14.1%, HR: 0.43; 95% CI: 0.16-1.15; P = 0.09) as compared with patients without a ReDS assessment. CONCLUSIONS: ReDS-guided HF therapy during RFU after HF hospitalization may be associated with lower risk of 30 day readmission.

Prognostic Impact of Prior Heart Failure in Patients Hospitalized With COVID-19.

BACKGROUND: Patients with pre-existing heart failure (HF) are likely at higher risk for adverse outcomes in coronavirus disease-2019 (COVID-19), but data on this population are sparse. OBJECTIVES: This study described the clinical profile and associated outcomes among patients with HF hospitalized with COVID-19. METHODS: This study conducted a retrospective analysis of 6,439 patients admitted for COVID-19 at 1 of 5 Mount Sinai Health System hospitals in New York City between February 27 and June 26, 2020. Clinical characteristics and outcomes (length of stay, need for intensive care unit, mechanical ventilation, and in-hospital mortality) were captured from electronic health records. For patients identified as having a history of HF by International Classification of Diseases-9th and/or 10th Revisions codes, manual chart abstraction informed etiology, functional class, and left ventricular ejection fraction (LVEF). RESULTS: Mean age was 63.5 years, and 45% were women. Compared with patients without HF, those with previous HF experienced longer length of stay (8 days vs. 6 days; p < 0.001), increased risk of mechanical ventilation (22.8% vs. 11.9%; adjusted odds ratio: 3.64; 95% confidence interval: 2.56 to 5.16; p < 0.001), and mortality (40.0% vs. 24.9%; adjusted odds ratio: 1.88; 95% confidence interval: 1.27 to 2.78; p = 0.002). Outcomes among patients with HF were similar, regardless of LVEF or renin-angiotensin-aldosterone inhibitor use. CONCLUSIONS: History of HF was associated with higher risk of mechanical ventilation and mortality among patients hospitalized for COVID-19, regardless of LVEF.

Challenges in heart transplantation during COVID-19: A single-center experience.

BACKGROUND: Orthotopic heart transplantation (OHT) recipients may be particularly vulnerable to coronavirus disease 2019 (COVID-19). OHT during the pandemic presents unique challenges in terms of feasibility and safety. METHODS: Chart review was performed for consecutive OHT recipients with COVID-19 and waitlisted patients who underwent OHT from March 1, 2020 to May 15, 2020. RESULTS: Of the approximately 400 OHT recipients followed at our institution, 22 acquired COVID-19. Clinical characteristics included median age 59 (range, 49-71) years, 14 (63.6%) were male, and median time from OHT to infection was 4.6 (2.5-20.6) years. Symptoms included fever (68.2%), gastrointestinal complaints (55%), and cough (46%). COVID-19 was severe or critical in 5 (23%). All patients had elevated inflammatory biomarkers. Immunosuppression was modified in 85% of patients. Most (n = 16, 86.4%) were hospitalized, 18% required intubation, and 14% required vasopressor support. Five patients (23%) expired. None of the patients requiring intubation survived. Five patients underwent OHT during the pandemic. They were all males, ranging from 30 to 59 years of age. Two were transplanted at United Network of Organ Sharing Status 1 or 2, 1 at Status 3, and 2 at Status 4. All were successfully discharged and are alive without allograft dysfunction or rejection. One contracted mild COVID-19 after the index hospitalization. CONCLUSION: OHT recipients with COVID-19 appear to have outcomes similar to the general population hospitalized with COVID-19. OHT during the pandemic is feasible when appropriate precautions are taken. Further study is needed to guide immunosuppression management in OHT recipients affected by COVID-19.

Advances in the Management of Acute Decompensated Heart Failure.

Patients hospitalized for heart failure pose a considerable clinical and financial burden on the health care system. Early recognition and deep phenotyping of heart failure for reduced and preserved ejection fraction syndromes facilitate the introduction of appropriate guideline-directed therapy and decongestion strategies to help improve heart failure morbidity and mortality. Robust and safe transitions of care programs are needed to deliver adequate care and improve overall survival.

Hemodynamic Response to Exercise in Patients Supported by Continuous Flow Left Ventricular Assist Devices.

OBJECTIVES: This study sought to characterize the hemodynamic response to exercise in LVAD-supported patients and identify parameters most strongly associated with peak oxygen consumption (VO2). BACKGROUND: Despite improved survival for heart failure patients afforded by continuous flow left ventricular assist devices (LVADs), peak exercise capacity remains impaired. Mechanisms underlying this reduced functional capacity remain poorly understood. METHODS: Patients referred for post-VAD hemodynamic optimization from December 2017 through June 2019 were enrolled. Swan Ganz catheters were inserted and upright incremental bicycle ergometry with respiratory gas analysis was performed. Hemodynamic measurements, mixed venous saturation, and arterial blood pressure were recorded every 3 min during exercise. Linear correlations were performed between peak VO2 (ml/min) and peak Fick cardiac output (CO), peak device flow, the assumed intrinsic CO derived as Fick CO-device flow, peak pressure differential across the LVAD (mean arterial pressure-pulmonary capillary wedge pressure), peak pressure differential across right ventricle (mean pulmonary artery pressure - right atrial pressure) and systemic vascular resistance. RESULTS: Forty-five patients supported by axial flow pumps (n = 12) and centrifugal flow pumps (n = 33) were studied. There were 34 men and 11 women. Age averaged 60 ± 10 years. Peak VO2 averaged 10.6 ± 3.1 ml/kg/min. Fick CO had the greatest correlation with peak VO2 with r = 0.73 (p < 0.0001) followed by intrinsic CO (r = 0.67; p < 0.0001). Multivariate model that best predicted peak VO2 included Fick CO and peak arterial venous oxygen (AVO2) difference. CONCLUSIONS: LVAD supported patients have severely impaired peak exercise capacity. The peak Fick cardiac output was the best correlate of peak exercise performance.