Pig-to-human heart xenotransplantation in two recently deceased human recipients
Genetically modified xenografts are one of the most promising solutions to the discrepancy between the numbers of available human organs for transplantation and potential recipients. To date, a porcine heart has been implanted into only one human recipient. Here, using 10-gene-edited pigs, we transplanted porcine hearts into two brain-dead human recipients and monitored xenograft function, hemodynamics and systemic responses over the course of 66 hours. Although both xenografts demonstrated excellent cardiac function immediately after transplantation and continued to function for the duration of the study, cardiac function declined postoperatively in one case, attributed to a size mismatch between the donor pig and the recipient. For both hearts, we confirmed transgene expression and found no evidence of cellular or antibody-mediated rejection, as assessed using histology, flow cytometry and a cytotoxic crossmatch assay. Moreover, we found no evidence of zoonotic transmission from the donor pigs to the human recipients. While substantial additional work will be needed to advance this technology to human trials, these results indicate that pig-to-human heart xenotransplantation can be performed successfully without hyperacute rejection or zoonosis.
Hemodynamic effects of COVID-19 vaccination in hospitalized patients awaiting heart transplantation
Background/UNASSIGNED:The hemodynamic effects of pre-transplant vaccination against COVID-19 among heart transplant candidates hospitalized for advanced heart failure remains unknown. Methods/UNASSIGNED:A retrospective chart review was conducted at a high-volume transplant center from January through December 2021. 22 COVID-19 vaccination events occurred among patients hospitalized for decompensated heart failure while awaiting transplantation. Primary outcomes included inotrope and vasopressor dosages. Secondary outcomes included vital signs, pulmonary artery catheter measurements, diuretic dosages, and renal function. Data were extracted 24Â h before through 72Â h after vaccination. Results/UNASSIGNED:One of 22 vaccination events was associated with hemodynamic changes requiring increased inotropic and vasopressor support post-vaccination. In all other cases, transient hemodynamic changes occurred without need for escalated therapy. Conclusions/UNASSIGNED:COVID-19 vaccination can be administered safely to most critically ill patients with advanced heart failure including those awaiting transplantation. All patients should be monitored closely as some may be susceptible to significant hemodynamic changes.
Hemodynamic Effects of COVID-19 Vaccination in Hospitalized Patients Awaiting Heart Transplantation [Meeting Abstract]
Purpose: The American Society of Transplantation and the International Society of Heart and Lung Transplantation recommend COVID-19 vaccination of transplant candidates to maximize immunity, as vaccination after initiation of immunosuppression may confer only partial immunity. However, there are concerns about the impact of vaccine-induced systemic inflammatory responses in critically ill patients with variable hemodynamic states. We aim to explore the safety of pre-transplant vaccination by examining the immediate impact of COVID-19 vaccination on the hemodynamics of hospitalized patients awaiting transplant.
Method(s): A retrospective chart review at a major transplant center was conducted among all heart transplant recipients from January 2021 through September 2021 who were hospitalized and listed or under consideration for listing for transplant at the time of COVID-19 vaccination. Primary outcomes included vital signs, hemodynamic parameters from pulmonary artery catheter-derived measurements, and changes in inotrope/vasopressor infusion rates. Data were extracted at fixed time points 24 hours before and up to 72 hours after vaccination. Given the small sample size and exploratory study nature, only univariate analysis was performed.
Result(s): Of the 50 patients who received heart transplants at our center from January 2021 through September 2021, 37 patients were vaccinated against COVID-19. 13 of those patients were vaccinated before transplant while hospitalized, and 10 of those 13 patients had a pulmonary artery catheter in place at the time of immunization. No significant changes in vital signs (blood pressure, heart rate), hemodynamics (cardiac index, pulmonary artery pressures, systemic vascular resistance), or vasopressor/inotrope infusion rates were observed after vaccination.
Conclusion(s): In this exploratory review of COVID-19 vaccination in heart transplant candidates, we did not detect any notable changes to hemodynamics in the first 72 hours after immunization. Although further investigative research is needed to assess COVID-19 vaccine safety comprehensively in patients with advanced heart failure, the absence of notable hemodynamic changes in this cohort of heart transplant candidates encourages the continued use of COVID-19 vaccination among hospitalized patients with advanced heart failure who are awaiting transplant.
Transplant Outcomes in Hearts with Moderate to Severe Left Ventricular Hypertrophy After the 2018 OPTN/UNOS Allocation Changes [Meeting Abstract]
Defining the Normal Values for Left Ventricular Global Longitudinal Strain in Adult Heart Transplanted Patients [Meeting Abstract]
IMPROVING ACCESS TO ADVANCED CARDIORESPIRATORY THERAPIES FOR UNDERSERVED PATIENTS AND MINORITIES WITH A MULTIDISCIPLINARY EXTRACORPOREAL MEMBRANE OXYGENATION (ECMO) PROGRAM IN A LARGE PUBLIC HOSPITAL NETWORK [Meeting Abstract]
Severe Acute Respiratory Syndrome Coronavirus 2 Infection and Thrombosis: Phlegmasia Cerulea Dolens Presenting with Venous Gangrene in a Child [Case Report]
A 12-year-old girl with severe acute respiratory syndrome coronavirus 2 infection presented as phlegmasia cerulea dolens with venous gangrene. Emergent mechanical thrombectomy was complicated by a massive pulmonary embolism and cardiac arrest, for which extracorporeal cardiopulmonary resuscitation and therapeutic hypothermia were used. Staged ultrasound-assisted catheter-directed thrombolysis was used for treatment of bilateral pulmonary emboli and the extensive lower extremity deep vein thrombosis while the patient received extracorporeal membrane oxygenation support. We highlight the need for heightened suspicion for occult severe acute respiratory syndrome coronavirus 2 infection among children presenting with unusual thrombotic complications.
ST-elevation myocardial infarction in a young patient with anomalous right coronary artery and COVID-19 pneumonia
Emergent TandemHeart-ECMO for acute severe mitral regurgitation with cardiogenic shock and hypoxaemia: a case series [Case Report]
Background /UNASSIGNED:Acute severe mitral regurgitation (MR) associated with cardiogenic shock is a life-threatening emergency. Traditional teaching has focused on the need for emergent coronary angiography and/or intra-aortic balloon counterpulsation in preparation for emergent open-heart surgery for repair/replacement. Unfortunately, emergent open-heart surgery in patients with acute MR complicated by cardiogenic shock is associated with 25-46% perioperative mortality. New devices have provided additional options for stabilization prior to emergent surgery which facilitate improved outcomes. Case summary /UNASSIGNED:mechanical circulatory support with an oxygenator spliced into the circuit, akin to veno-arterial extracorporeal membrane oxygenation (ECMO), facilitated haemodynamic stabilization and decongestion of the lungs facilitating successful bridge to mitral valve surgery. Successful discharge to home was achieved in both patients with good neurological outcomes and sustained long-term functional recovery at 18 and 14â€‰months, respectively. Discussion/UNASSIGNED:, with or without ECMO, facilitates management of the critically ill cardiogenic shock patient with acute severe MR.
Efficacy of Manual Hemostasis for Percutaneous Axillary Artery Intra-Aortic Balloon Pump Removal
Background/UNASSIGNED:The prevalence of peripheral vascular disease has led to the re-emergence of percutaneous axillary vascular access as a suitable alternative access site to femoral artery. We sought to investigate the efficacy and safety of manual hemostasis in the axillary artery. Methods/UNASSIGNED:Data were collected from a prospective internal registry of patients who had a MaquetÂ® (Rastatt, Germany) Mega 50â€‰cc intra-aortic balloon pumps (IABP) placed in the axillary artery position. They were anticoagulated with weight-based intravenous heparin to maintain an activated partial thromboplastin time (aPTT) of 50-80 seconds. Anticoagulation was discontinued 2 hours prior to the device explantation. Manual compression was used to achieve the hemostasis of the axillary artery. Vascular and bleeding complications attributable to manual hemostasis were classified based on the Valve Academic Research Consortium-2 (VARC-2) and Bleeding Academic Research Consortium-2 (BARC-2) classifications, respectively. Results/UNASSIGNED:29 of 46 patients (63%) achieved axillary artery homeostasis via manual compression. The median duration of IABP implantation was 12 days (range 1-54 days). Median compression time was 20 minutes (range 5-60 minutes). There were no major vascular or bleeding complications as defined by the VARC-2 and BARC-2 criteria, respectively. Conclusion/UNASSIGNED:Manual compression of the axillary artery appears to be an effective and safe method for achieving hemostasis. Large prospective randomized control trials may be needed to corroborate these findings.