Stiff right atrial syndrome? A complex clinical case report utilizing multimodality imaging and invasive hemodynamics.

Background: Stiff left atrial syndrome is a well-established cause of heart failure symptoms. A parallel entity involving the right atrium (RA) has not previously been described. We present a case of refractory right heart failure (RHF) 12 years following orthotopic heart transplantation. Case summary: Patient underwent annuloplasty ring placement for severe tricuspid regurgitation in 2018 and kidney transplantation in 2020. The use of multimodality imaging and a multidisciplinary approach suggested a stiff RA as a potential etiology to refractory symptoms. Redo-heart and kidney transplantation in March 2021 led to the resolution of symptoms without recurrence. Discussion: We propose stiff right atrial syndrome that may need to be considered in the setting of refractory RHF primarily suggested by significant right atrial enlargement and restrictive physiology.

Comparative Analysis of Coronavirus disease 2019 Vaccine Efficacy in Heart Transplant Recipients on Standardized Immunotherapy Regimens.

Objective: To assess the effect of coronavirus disease 2019 (COVID-19) infection on heart transplant recipients requiring immunotherapy. To investigate the effectiveness of vaccination in immunosuppressed heart transplant recipients during the initial years of the COVID-19 pandemic, and to examine the timing of COVID-19 infections in heart transplant recipients' posttransplantation. Patients and Methods: International data on COVID-19 infection in immunosuppressed populations is limited. Heart transplant recipients requiring immunotherapy are at risk for increased complications with COVID-19 infection. The availability of vaccination and temporal trends in this population has not been well described. We report outcomes in immunosuppressed patients during the initial years of the COVID-19 pandemic from March 1, 2019, to October 31, 2021, at Mayo Clinic in Florida. Results: A total of 98 patients were reviewed, of which 49 were COVID-19-positive (CP), and 49 were negative (CN). The cohort was well matched, with a median age of 58 years (49-65 years) in both groups. Females consisted of 41% in the CP group and 18.4% in the CN group. Immunosuppression was not significantly different for CP or CN patients. The median time from transplant to CP was 384 days (237-677 days). The CN group's median follow-up after transplant was 947 days (737-1191 days). The CP hospitalization rate was 24% with only 1 death. More CP patients were vaccinated than the CN group (92% vs 78%, P=.025). Conclusion: Our study sheds light on COVID-19's effect on heart transplant recipients and vaccination in this population. Our findings suggest a potentially heightened infection risk within the first 1.5 years posttransplant, highlighting the need to optimize management strategies and vaccine efficacy in this vulnerable group.

Axillary mechanical circulatory support improves renal function prior to heart transplantation in patients with chronic kidney disease.

Impaired kidney function is often associated with acute decompensation of chronic heart failure and portends a poor prognosis. Unfortunately, current data have demonstrated worse survival in patients with acute kidney injury than in patients with chronic kidney disease during durable LVAD placement as bridge therapy. Furthermore, end-stage heart failure patients undergoing combined heart-kidney transplantation have poorer short- and long-term survival than heart transplants alone. We evaluated the kidney function recovery in our heart failure population awaiting heart transplantation at our institution, supported by temporary Mechanical Circulatory Support (tMCS) with Impella 5.5. The protocol (#22004000) was approved by the Mayo Clinic institutional review board, after which we performed a retrospective review of all patients with acute on chronic heart failure and kidney disease in patients considered for only heart and kidney combined organ transplant and supported by tMCS between January 2020 and February 2021. Hemodynamic and kidney function trends were recorded and analyzed before and after tMCS placement and transplantation. After placement of tMCS, we observed a trend towards improvement in creatinine, Fick cardiac index, mixed venous saturation, and glomerular filtration rate (GFR), which persisted through transplantation and discharge. The average duration of support with tMCS was 16.5 days before organ transplantation. The median pre-tMCS creatinine was 2.1 mg/dL (IQR 1.75-2.3). Median hematocrit at the time of tMCS placement was 32% (IQR 32-34), and the median estimated glomerular filtration rate was 34 mL/min/BSA (34-40). The median GFR improved to 44 mL/min/BSA (IQR 45-51), and serum creatinine improved to 1.5 mg/dL (1.5-1.8) after tMCS. Median discharge creatinine was 1.1 mg/dL (1.19-1.25) with a GFR of 72 (65-74). None of these six patients supported with tMCS required renal replacement therapy after heart transplantation. Early adoption of Impella 5.5 in this patient population resulted in renal recovery without needing renal replacement therapies or dual organ transplantation and should be further evaluated.

Revisiting Pulmonary Hypertension in the Era of Temporary Mechanical Circulatory Support - Literature Review and Case-Based Discussion.

BACKGROUND: Pulmonary arterial hypertension (PAH) is characterized by persistently increased pressure in the pulmonary arteries. New defining criteria for the different hemodynamic types of pulmonary hypertension (PH) that occur with left heart disease have been proposed by the task force on PH. After consideration of the changes in the general definition of PH in left heart disease, the proposed hemodynamic definition was: (1) isolated postcapillary PH: pulmonary artery wedge pressure >15 mm Hg and mean pulmonary arterial pressure (mPAP) >20 mm Hg and pulmonary vascular resistance (PVR) <3 Woods units (WU); and (2) combined post- and precapillary PH: pulmonary artery wedge pressure >15 mm Hg, mPAP >20 mm Hg, and PVR ≥3 WU. Secondary PH is initially reversible, but eventually, it can become fixed because of the remodeling process of the pulmonary vascular system. Limitations in defining both the time for and amount of reversibility lack clarity. We discuss a case of PH as a framework to better understand these key principles in addressing patients' candidacy for heart or heart-lung transplantation. METHODS: We performed a literature search for all available contemporary data with the following terms: "pulmonary hypertension," "reversal," "Impella 5.5," "temporary mechanical support," and "LVAD" using the National Library of Medicine - PubMed and PubMed Central between 2019 and 2023. A total of 14 published papers were found with these search. From these, 3 addressed the issue of PH and reversibility in the setting of LHD after durable LVAD placement. No papers were found using Impella 5.5 and PH during this timeframe. Given the paucity of data in the field regarding temporary mechanical circulatory support and pulmonary hypertension, we present a case-based discussion to guide the reader in understanding the potential impact of this method in patients with WHO Class 2 Pulmonary hypertension. CASE: A 49-year-old woman with a medical history of acute on chronic biventricular systolic and diastolic heart failure, American College of Cardiology stage D, Stevenson profile C, New York Heart Association class IV (ejection fraction 18%) secondary to nonischemic cardiomyopathy after cardiac resynchronization therapy, pulmonary hypertension, bilateral deep vein thrombosis, and segmental pulmonary embolism presented for heart transplant evaluation. Her cardiac output and central hemodynamics were measured, and she was found to have a pulmonary artery (PA) pressure of 78/38 with a mean PA pressure of 51, pulmonary capillary wedge pressure (PCWP) 30, transpulmonary pressure gradient (TPG) 21, thermodilution cardiac output (CO) 3.35 L/min, and cardiac input (CI) 1.75 L/min/m2. Her PVR was 6.2 WU. Provocative pharmacologic testing for reversibility of PH was performed using sodium nitroprusside, which resulted in a blood pressure of 83/57 (92), heart rate 92/min, and PA pressure of 71/31, with a mean PA pressure of 44 PCWP 22, TPG 22, CO 4.8 L/min, and CI of 2.48 L/min/m2 with a PVR of 4.5 WU. Following this, the patient underwent Impella 5.5 placement through the right axillary artery to optimize afterload reduction and improve end-organ perfusion. Post-Impella hemodynamics on milrinone 0.5 mcg/kg/min demonstrated the following: blood pressure 90/66 (74), heart rate 53/min, and PA pressure of 56/29, with a mean PA pressure of 38, PCWP 24, TPG 14, CO 6 L/min, and CI of 2.9 L/min/m2 with a PVR of 2.3 WU. CONCLUSION: Left ventricular assist device support with Impella 5.5 is associated with a reduction in mPAP and PVR over weeks to months and thus plays a crucial role as a bridge to transplant. Our case and this review highlights the characteristics of PH resulting from heart failure with reduced ejection fraction and discusses the important clinical issues related to the treatment of these patients. We have shown that left ventricular assist device therapy with Impella 5.5 can effectively reduce left-sided filling pressures and lead to PH improvement. We demonstrate the potential benefits of Impella 5.5 in the management of patients with WHO 2 PH and cardiogenic shock with impaired hemodynamics.

Percutaneous Axillary Left Ventricular Support as a Lifesaving Measure for Peripartum Cardiomyopathy Shock: A Case Report.

Peripartum cardiomyopathy (PPCM) affects women at the end of pregnancy or after delivery. Symptoms overlapping with pregnancy decrease the diagnostic yield of PPCM and can increase the rate of maternal mortality. As clinicians manage high-risk patients, it is crucial to understand the variable maternal physiology both during and after childbirth. Effective management of high-risk patients necessitates a comprehensive understanding of the variable maternal physiology during and after childbirth. The importance of prompt intervention with Impella CP (Cardiac Power) to treat acute cardiogenic shock stemming from PPCM after cesarean should be considered. Clinical outcomes can be improved by emphasizing the need for timely intervention and incorporating a comprehensive understanding of maternal physiology. The authors present a case of Impella CP use in PPCM shock as a means for emergent support after cesarean.

Trends and predictors of intracranial hemorrhage in patients with advanced heart failure on left ventricular assist device from 2005 to 2014 in the United States.

OBJECTIVES: Left ventricular assist devices are known to extend survival in patients with advanced heart failure; however, their association with intracranial hemorrhage is also well-known. We aimed to explore the risk trend and predictors of intracranial hemorrhage in patients with left ventricular assist devices. MATERIAL AND METHODS: We included patients aged 18 years or older with left ventricular assist devices hospitalized in the US from 2005 to 2014 using the National Inpatient Sample. We computed the survey-weighted percentages with intracranial hemorrhage across the 10-year study period and assessed whether the proportions changed over time. Predictors of intracranial hemorrhage were evaluated using multivariable logistic regression model. RESULTS: Of 33,246 hospitalizations, 568 (1.7%) had intracranial hemorrhage. The number of left ventricular assist devices placements increased from 873 in 2005 to 5175 in 2014. However, the risk of intracranial hemorrhage remained largely unchanged (1.7% to 2.3%; linear trend, P = 0.604). The adjusted odds of intracranial hemorrhage were increased with the presence of one of the following variables: female sex (odds ratio [OR], 1.58; 95% CI, 1.03-2.43), history of ischemic stroke (OR, 3.13; 95% CI, 1.86-5.28), or Charlson Comorbidity Index score of 3 or more (OR, 77.40; 95% CI, 10.03-597.60). CONCLUSIONS: Over the last decade, the risk of intracranial hemorrhage has remained relatively unchanged despite an increase in the use of left ventricular assist devices in patients with advanced heart failure. Women, higher Charlson Comorbidity Index scores, and history of ischemic stroke were associated with higher odds of intracranial hemorrhage in patients with left ventricular assist devices.

One-year survival in recipients older than 50 bridged to heart transplant with Impella 5.5 via axillary approach.

BACKGROUND: Optimizing patients with advanced heart failure before orthotopic heart transplantation (OHT), especially in patients greater than 50 years old, is imperative to achieving successful post-transplant outcomes. Complications are well-described for patients bridged to transplant (BTT) with durable left ventricular assist device (LVAD) support. Given the lack of data available in older recipients after the recent increase in mechanical support use, we felt it crucial to report our center's one-year outcomes in older recipients after heart transplantation with percutaneously placed Impella 5.5 as a BTT. METHODS: Forty-nine OHT patients were supported with the Impella 5.5 intended as a bridge between December 2019 and October 2022 at Mayo Clinic in Florida. Data were extracted from the electronic health record at baseline and during their transplant episode of care after Institutional Review Boards approval as exempt for retrospective data collection. RESULTS: Thirty-eight patients aged 50 or older were supported with Impella 5.5 as BTT. Ten patients underwent heart and kidney transplantation within this cohort. The median age at OHT was 63 (58-68) years, with 32 male (84%) and six female patients (16%). Etiology was divided into ischemic (63%) and non-ischemic cardiomyopathy (37%). The baseline median ejection fraction was 19% (15-24). Most patients were in blood group O (60%), and 50% were diabetic. The average duration of support was 27 days (range 6-94). The median duration of follow-up is 488 days (185-693). For patients that have reached the 1-year follow-up timeframe (22 of 38, 58%), the 1-year post-transplant survival is 95%. CONCLUSION: Our single-center data provides awareness for using the Impella 5.5 percutaneously placed axillary support device in older heart failure patients in cardiogenic shock as a bridge to transplantation. One-year survival outcomes after heart transplantation are excellent despite the older recipient's age and prolonged pre-transplant support.

Donation after circulatory death: A transplant cardiologist's take on neuroprognostication.

Donation after circulatory death (DCD) is becoming increasingly utilized in heart transplantation and has the potential to further expand the donor pool. As transplant cardiologists gain more familiarity with DCD donor selection, there are many issues that lack consensus including how we incorporate the neurologic examination, how we measure functional warm ischemic time (fWIT), and what fWIT thresholds are acceptable. DCD donor selection calls for prognostication tools to help determine how quickly a donor may expire, and in current practice there is no standardization in how we make these predictions. Current scoring systems help to determine which donor may expire within a specified time window either require the temporary disconnection of ventilatory support or do not incorporate any neurologic examination or imaging. Moreover, the specified time windows differ from other DCD solid organ transplantation without standardization or strong scientific justification for these thresholds. In this perspective, we highlight the challenges faced by transplant cardiologists as they navigate the muddy waters of neuroprognostication in DCD cardiac donation. Given these difficulties, this is also a call to action for the creation of a more standardized approach to improve the DCD donor selection process for appropriate resource allocation and organ utilization.

Variation in Hemodynamic Assessment and Interpretation: A Call to Standardize the Right Heart Catheterization.

BACKGROUND: Invasive hemodynamic measurement via right heart catheterization has shown divergent data in its role in the treatment of patients with heart failure (HF) and cardiogenic shock. We hypothesized that variation in data acquisition technique and interpretation might contribute to these observations. We sought to assess differences in hemodynamic acquisition and interpretation by operator subspecialty as well as level of experience. METHODS AND RESULTS: Individual-level responses to how physicians both collect and interpret hemodynamic data at the time of right heart catheterization was solicited via a survey distributed to international professional societies in HF and interventional cardiology. Data were stratified both by operator subspecialty (HF specialists or interventional cardiologists [IC]) and operator experience (early career [≤10 years from training] or late career [>10 years from training]) to determine variations in clinical practice. For the sensitivity analysis, we also look at differences in each subgroup. A total of 261 responses were received. There were 141 clinicians (52%) who self-identified as HF specialists, 99 (38%) identified as IC, and 20 (8%) identified as other. There were 142 early career providers (54%) and late career providers (119 [46%]). When recording hemodynamic values, there was considerable variation in practice patterns, regardless of subspecialty or level of experience for the majority of the intracardiac variables. There was no agreement or mild agreement among HF and IC as to when to record right atrial pressures or pulmonary capillary wedge pressures. HF cardiologists were more likely to routinely measure both Fick and thermodilution cardiac output compared with IC (51% vs 29%, P < .001), something mirrored in early career vs later career cardiologists. CONCLUSIONS: Significant variation exists between the acquisition and interpretation of right heart catheterization measurements between HF and IC, as well as those early and late in their careers. With the growth of the heart team approach to management of patients in cardiogenic shock, standardization of both assessment and management practices is needed.

Short-term outcomes of heart transplant patients bridged with Impella 5.5 ventricular assist device.

AIMS: We sought to investigate the outcomes of heart transplant patients supported with Impella 5.5 temporary mechanical circulatory support. METHODS AND RESULTS: Patient demographics, perioperative data, hospital timeline, and haemodynamic parameters were followed during initial admission, Impella support, and post-transplant period. Vasoactive-inotropic score, primary graft failure, and complications were recorded. Between March 2020 and March 2021, 16 advanced heart failure patients underwent Impella 5.5 temporary left ventricular assist device support through axillary approach. Subsequently, all these patients had heart transplantation. All patients were either ambulatory or chair bound during their temporary mechanical circulatory support until heart transplantation. Patients were kept on Impella support median of 19 days (3-31) with the median lactate dehydrogenase level of 220 (149-430). All Impella devices were removed during heart transplantation. During Impella support, patients had improved renal function with median creatinine serum level of 1.55 mg/dL decreased to 1.25 (P = 0.007), pulmonary artery pulsatility index scores increased from 2.56 (0.86-10) to 4.2 (1.3-10) (P = 0.048), and right ventricular function improved (P = 0.003). Patients maintained improved renal function and favourable haemodynamics after their heart transplantation as well. All patients survived without any significant morbidity after their heart transplantation. CONCLUSIONS: Impella 5.5 temporary left ventricular assist device optimizes care of heart transplant recipients providing superior haemodynamic support, mobility, improved renal function, pulmonary haemodynamics, and right ventricular function. Utilizing Impella 5.5 as a direct bridging strategy to heart transplantation resulted in excellent outcomes.

Extracorporeal Membrane Oxygenation-Impella (ECPELLA) in a Patient With Recalcitrant Ventricular Tachycardia Undergoing Ablation.

In advanced heart failure, refractory hemodynamically unstable ventricular tachycardia (VT) can be life-threatening. The utilization of short-term temporary mechanical circulatory support (MCS) has been described. Still, it is limited to the intra-aortic balloon pump (IABP) or Impella 2.5/CP (Abiomed Inc., Danvers, MA, USA) which may only provide up to 1-2.5 L/min of added support. Escalation of MCS therapies should be considered. Referrals to advanced tertiary heart transplant centers should be done early to afford patients the best chance at an optimal outcome, with the option for heart transplant evaluation if needed. We present a case of recalcitrant hemodynamically unstable VT complicated by cardiac arrest, eventually undergoing successful VT ablation while supported on veno-arterial extracorporeal membrane oxygenation (VA ECMO) and Impella 5.5 as a vent strategy in the extracorporeal membrane oxygenation-Impella (ECPELLA) configuration.

Non-invasive detection of cardiac allograft rejection among heart transplant recipients using an electrocardiogram based deep learning model.

Aims: Current non-invasive screening methods for cardiac allograft rejection have shown limited discrimination and are yet to be broadly integrated into heart transplant care. Given electrocardiogram (ECG) changes have been reported with severe cardiac allograft rejection, this study aimed to develop a deep-learning model, a form of artificial intelligence, to detect allograft rejection using the 12-lead ECG (AI-ECG). Methods and results: Heart transplant recipients were identified across three Mayo Clinic sites between 1998 and 2021. Twelve-lead digital ECG data and endomyocardial biopsy results were extracted from medical records. Allograft rejection was defined as moderate or severe acute cellular rejection (ACR) based on International Society for Heart and Lung Transplantation guidelines. The extracted data (7590 unique ECG-biopsy pairs, belonging to 1427 patients) was partitioned into training (80%), validation (10%), and test sets (10%) such that each patient was included in only one partition. Model performance metrics were based on the test set (n = 140 patients; 758 ECG-biopsy pairs). The AI-ECG detected ACR with an area under the receiver operating curve (AUC) of 0.84 [95% confidence interval (CI): 0.78-0.90] and 95% (19/20; 95% CI: 75-100%) sensitivity. A prospective proof-of-concept screening study (n = 56; 97 ECG-biopsy pairs) showed the AI-ECG detected ACR with AUC = 0.78 (95% CI: 0.61-0.96) and 100% (2/2; 95% CI: 16-100%) sensitivity. Conclusion: An AI-ECG model is effective for detection of moderate-to-severe ACR in heart transplant recipients. Our findings could improve transplant care by providing a rapid, non-invasive, and potentially remote screening option for cardiac allograft function.

Packing the donor heart: Is SherpaPak cold preservation technique safer compared to ice cold storage.

INTRODUCTION: The present study aimed to compare the clinical outcomes of heart transplant patients whose donor hearts were preserved with the SherpaPak controlled cold organ system versus the conventional ice storage technique. METHODS: All patients undergoing heart transplantation at our center between January 2019 and April 2021 were divided into two groups according to the technique used during donor heart preservation and transport. The first group consisted of 34 SherpaPak controlled temperature preservation patients, and the second group consisted of 47 patients where the conventional three bags and ice technique was utilized during organ transportation. The two groups were compared based on demographics, operative details, and postoperative outcomes. RESULTS: There were no significant differences between the groups regarding Vasoactive Inotropic Score (VIS), Primary Graft Dysfunction (PGD), and the need for a transient pacer. However, the VIS, PGD, and pacing trends were lower in the SherpaPak patients even though the total ischemic and cardiopulmonary bypass times were significantly longer. Furthermore, SherpaPak patients exhibited a shorter stay in the ICU with no severe PGD and mortality. CONCLUSION: The SherpaPak donor heart preservation provides safe outcomes in heart transplant patients. Further research is needed to utilize this method for longer durations of ischemic time and expand travel distances for organ transportation.