Faculty Bibliography

OBJECTIVE:This pilot study sought to evaluate the feasibility of our donation after circulatory death (DCD) heart transplantation protocol using cardiopulmonary bypass (CPB) for normothermic regional reperfusion (NRP). METHODS:Suitable local DCD candidates were transferred to our institution. Life support was withdrawn in the operating room (OR). On declaration of circulatory death, sternotomy was performed, and the aortic arch vessels were ligated. CPB was initiated with left ventricular venting. The heart was reperfused, with correction of any metabolic abnormalities. CPB was weaned, and cardiac function was assessed at 30-minute intervals. If accepted, the heart was procured with cold preservation and transplanted into recipients in a nearby OR. RESULTS:Between January 2020 and January 2021, a total of 8 DCD heart transplants were performed: 6 isolated hearts, 1 heart-lung, and 1 combined heart and kidney. All donor hearts were successfully resuscitated and weaned from CPB without inotropic support. Average lactate and potassium levels decreased from 9.39 ± 1.47 mmol/L to 7.20 ± 0.13 mmol/L and 7.49 ± 1.32 mmol/L to 4.36 ± 0.67 mmol/L, respectively. Post-transplantation, the heart-lung transplant recipient required venoarterial extracorporeal membrane oxygenation for primary lung graft dysfunction but was decannulated on postoperative day 3 and recovered uneventfully. All other recipients required minimal inotropic support without mechanical circulatory support. Survival was 100% with a median follow-up of 304 days (interquartile range, 105-371 days). CONCLUSIONS:DCD heart transplantation outcomes have been excellent. Our DCD protocol is adoptable for more widespread use and will increase donor heart availability in the United States.

BACKGROUND:Severe coronavirus disease 2019 (COVID-19) can cause acute respiratory failure requiring mechanical ventilation. Venovenous (VV) extracorporeal membrane oxygenation (ECMO) has been used in patients in whom conventional mechanical ventilatory support has failed. To date, published data have focused on survival from ECMO and survival to discharge. In addition to survival to discharge, this study reports 1-year follow-up data for patients who were successfully discharged from the hospital. METHODS:A single-institution, retrospective review of all patients with severe COVID-19 who were cannulated for VV-ECMO between March 10, 2020 and May 1, 2020 was performed. A multidisciplinary ECMO team evaluated, selected, and managed patients with ECMO support. The primary outcome of this study was survival to discharge. Available 1-year follow-up data are also reported. RESULTS:A total of 30 patients were supported with VV-ECMO, and 27 patients (90%) survived to discharge. All patients were discharged home or to acute rehabilitation on room air, except for 1 patient (3.7%), who required supplemental oxygen therapy. At a median follow-up of 10.8 months (interquartile range [IQR], 8.9-14.4 months) since ECMO cannulation, survival was 86.7%, including 1 patient who underwent lung transplantation. Of the patients discharged from the hospital, 44.4% (12/27) had pulmonary function testing, with a median percent predicted forced expiratory volume of 100% (IQR, 91%-110%). For survivors, a 6-minute walk test was performed in 59.3% (16/27), with a median value of 350 m (IQR, 286-379 m). CONCLUSIONS:A well-defined patient selection and management strategy of VV-ECMO support in patients with severe COVID-19 resulted in exceptional survival to discharge that was sustained at 1-year after ECMO cannulation.

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.

OBJECTIVES/OBJECTIVE:Patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may develop end-stage lung disease requiring lung transplantation. We report the clinical course, pulmonary pathology with radiographic correlation, and outcomes after lung transplantation in three patients who developed chronic respiratory failure due to postacute sequelae of SARS-CoV-2 infection. METHODS:A retrospective histologic evaluation of explanted lungs due to coronavirus disease 2019 was performed. RESULTS:None of the patients had known prior pulmonary disease. The major pathologic findings in the lung explants were proliferative and fibrotic phases of diffuse alveolar damage, interstitial capillary neoangiogenesis, and mononuclear inflammation, specifically macrophages, with varying numbers of T and B lymphocytes. The fibrosis varied from early collagen deposition to more pronounced interstitial collagen deposition; however, pulmonary remodeling with honeycomb change was not present. Other findings included peribronchiolar metaplasia, microvascular thrombosis, recanalized thrombi in muscular arteries, and pleural adhesions. No patients had either recurrence of SARS-CoV-2 infection or allograft rejection following transplant at this time. CONCLUSIONS:The major pathologic findings in the lung explants of patients with SARS-CoV-2 infection suggest ongoing fibrosis, prominent macrophage infiltration, neoangiogenesis, and microvascular thrombosis. Characterization of pathologic findings could help develop novel management strategies.

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.

BACKGROUND: Coronavirus disease-19 (COVID-19) remains a public health crisis. The epidemiology of COVID-19-associated large- and medium-sized-vessel pathology is not well characterized. The aim of this study is to identify patients with possible COVID-19-associated large- and medium-sized-vessel pathology based on computed tomography (CT) imaging to provide insight into this rare, but potentially devastating, cardiovascular manifestation. METHODS: This is a single-center retrospective review of patients with CT chest, abdomen, and/or pelvis concerning for large- and medium-vessel pathology and confirmed COVID-19 infection from March 1, 2020 to October 31, 2020. RESULTS: During the study period, 6,553 CT reports were reviewed and pertinent imaging was identified in 139 patients. Of these, 8 patients (median age: 59 years, range 51-82) were COVID-19 positive. All patients had preexisting cardiovascular risk factors and three (37.5%) had an autoimmune disease. Four patients were never hospitalized for COVID-19. Among these, two presented to the hospital at a median of 39 days (range: 27-50) after their initial COVID-19 test with chest and back pain where imaging revealed extensive aortic pathology. One patient required surgical management for aortic pathology. All other patients were treated with expectant management and outpatient follow-up. CONCLUSION/CONCLUSIONS: The clinical and radiological presentations of COVID-19-associated large- and medium-vessel pathology are heterogeneous and can be a late finding after COVID-19 recovery. Close clinical follow-up and surveillance imaging for large- and medium-sized-vessel pathology may be warranted in COVID-19 patients.