Faculty Bibliography

INTRODUCTION/BACKGROUND:ImmuKnow, an immune cell function assay that quantifies overall immune system activity can assist in post-transplant immunosuppression adjustment. However, the utility of pre-transplant ImmuKnow results representing a patient's baseline immune system activity is unknown. This study sought to assess if pre-transplant ImmuKnow results are predictive of rejection at the time of first biopsy in our cardiac transplant population. METHODS:This is a single center, retrospective observational study of consecutive patients from January 1, 2018 to October 1, 2020 who underwent orthotopic cardiac transplantation at NYU Langone Health. Patients were excluded if a pre-transplant ImmuKnow assay was not performed. ImmuKnow results were categorized according to clinical interpretation ranges (low, moderate, and high activity), and patients were divided into two groups: a low activity group versus a combined moderate-high activity group. Pre-transplant clinical characteristics, induction immunosuppression use, early postoperative tacrolimus levels, and first endomyocardial biopsy results were collected for all patients. Rates of clinically significant early rejection (defined as rejection ≥ 1R/1B) were compared between pre-transplant ImmuKnow groups. RESULTS:Of 110 patients who underwent cardiac transplant, 81 had pre-transplant ImmuKnow results. The low ImmuKnow activity group was comprised of 15 patients, and 66 patients were in the combined moderate-high group. Baseline characteristics were similar between groups. Early rejection occurred in 0 (0%) patients with low pre-transplant ImmuKnow levels. Among the moderate- high pre-transplant ImmuKnow group, 16 (24.2%) patients experienced early rejection (P = .033). The mean ImmuKnow level in the non-rejection group was the 364.9 ng/ml of ATP compared to 499.3 ng/ml of ATP for those with rejection (P = .020). CONCLUSION/CONCLUSIONS:Patients with low pre-transplant ImmuKnow levels had lower risk of early rejection when compared with patients with moderate or high levels. Our study suggests a possible utility in performing pre-transplant ImmuKnow to identify patients at-risk for early rejection who may benefit from intensified upfront immunosuppression as well as to recognize those where slower calcineurin inhibitor initiation may be appropriate.

BACKGROUND:Specific aetiologies of cardiomyopathy can significantly impact treatment options as well as appropriateness and prioritisation for advanced heart failure therapies such as ventricular assist device (VAD) or orthotopic heart transplantation (OHT). We reviewed the tissue diagnoses of patients who underwent advanced therapies for heart failure (HF) to identify diagnostic discrepancies. METHODS:This study presents a retrospective cohort of the aetiology of cardiomyopathy in 118 patients receiving either durable VAD or OHT. Discrepancies between the preoperative aetiological diagnosis of cardiomyopathy with the pathological diagnosis were recorded. Echocardiographic and haemodynamic data were reviewed to examine differences in patients with differing aetiological diagnoses. RESULTS:Twelve (12) of 118 (12/118) (10.2%) had a pathological diagnosis that was discordant with pre-surgical diagnosis. The most common missed diagnoses were infiltrative cardiomyopathy (5) and hypertrophic cardiomyopathy (3). Patients with misidentified aetiology of cardiomyopathy had smaller left ventricular (LV) dimensions on echocardiography than patients with dilated cardiomyopathy (5.8±0.9 vs 6.7±1.1 respectively p=0.01). CONCLUSIONS:Most HF patients undergoing VAD and OHT had a correct diagnosis for their heart failure prior to treatment, but a missed diagnosis at time of intervention (VAD or OHT) was not uncommon. Smaller LV dimension on echocardiogram in a patient with a non-ischaemic cardiomyopathy warrants further workup for a more specific aetiology.

Intra-aortic balloon pumps (IABPs) can be used to provide hemodynamic support in patients with end-stage heart failure as a bridge to transplantation (BTT). The IABP is commonly inserted via the common femoral artery, which can limit patients' mobility. The Ramsey protocol, developed by a critical care physical therapist, allows patients with femoral IABPs to ambulate with the assistance of a tilt table. The aim of this study was to determine the safety and feasibility of a modified Ramsey protocol for early mobilization of patients with femoral IABPs as BTT. This is a retrospective single-center review of patients with femoral IABPs as BTT using a tilt table protocol from May 2019 to May 2020. Primary outcomes were time to successful ambulation, number of successful ambulation events, and ambulation-associated adverse events, including IABP augmentation, waveform, positioning changes, and vascular complications at the insertion site. Twenty-four patients (mean age 55 ± 16 years) underwent femoral IABP insertion as BTT and were mobilized following our protocol. Nineteen patients (79.2%) successfully ambulated with a median of three sessions (interquartile range, 2-4) per patient. The median time from IABP insertion to ambulation was 3 days (interquartile range, 2-5). Twenty-one patients underwent heart transplantation, of which all 19 who ambulated were successfully bridged to transplantation. Early mobilization in select patients with femoral IABPs can be performed safely and successfully, avoiding the deleterious effects of bed rest that have been historically seen in this patient population.

This paper responds to the position statement released by the American College of Physicians (ACP) entitled "Ethics, Determination of Death, and Organ Transplantation in Normothermic Regional Perfusion (NRP) with Controlled Donation after Circulatory Determination of Death (cDCD): American College of Physicians Statement of Concern." The ACP's statement engages with critical ethical issues surrounding cDCD NRP, but several of their conclusions are flawed. Contrary to the statement, the practice respects the dead donor rule and the legal definition of death while honoring the wishes of the deceased and their loved ones to help save the lives of those in need of organ transplants. cDCD NRP is well established in many countries, it can enhance trust in medical practice and organ donation, and will increase the availability of optimal organs for life-saving transplants.

Purpose: In the U.S., heart transplantation from donation after circulatory death (DCD) is increasing. We present our institutional experience of DCD transplantation by using a thoracoabdominal-normothermic regional perfusion (TA-NRP) protocol and compare the results to a cohort concomitantly transplanted, from standard brain death (

BACKGROUND:The VentriFlo® True Pulse Pump (VentriFlo, Inc., Pelham, NH, USA) is a new pulsatile blood pump intended for use during short-term circulatory support. The purpose of this study was to evaluate the feasibility of the VentriFlo and compare it to a conventional centrifugal pump (ROTAFLOW, Getinge, Gothenberg, Sweden) in acute pig experiments. METHODS:Pigs (40-45 kg) were supported by cardiopulmonary bypass (CPB) with the VentriFlo (n=9) or ROTAFLOW (n=5) for 6 hours. Both VentriFlo and ROTAFLOW circuits utilized standard CPB components. We evaluated hemodynamics, blood chemistry, gas analysis, plasma hemoglobin, and microcirculation at the groin skin with computer-assisted video microscopy (Optilia, Sollentuna, Sweden). RESULTS:Pigs were successfully supported by CPB for 6 hours without any pump-related complications in either group. The VentriFlo delivered an average stroke volume of 29.2 ± 4.8 mL. VentriFlo delivered significantly higher pulse pressure (29.1 ± 7.2 mm Hg vs 4.4 ± 7.0 mm Hg, p<0.01) as measured in the carotid artery, with mean aortic pressure and pump flow comparable with those in ROTAFLOW. In blood gas analysis, arterial pH was significantly lower after five hours support in the VentriFlo group (7.30 ± 0.07 vs 7.43 ± 0.03, p=0.001). There was no significant difference in plasma hemoglobin level in both groups after six hours of CPB support. In microcirculatory assessment, VentriFlo tended to keep normal capillary flow, but it was not statistically significant. CONCLUSIONS:VentriFlo-supported pigs showed comparable hemodynamic parameters with significantly higher pulse pressure compared to ROTAFLOW without hemolysis.