Utility of a fusion protein T-cell co-stimulation blocker Belatacept in heart transplant recipients: Real world experience from a high volume center.

BACKGROUND: Belatacept (BTC), a fusion protein, selectively inhibits T-cell co-stimulation by binding to the CD80 and CD86 receptors on antigen-presenting cells (APCs) and has been used as immunosuppression in adult renal transplant recipients. However, data regarding its use in heart transplant (HT) recipients are limited. This retrospective cohort study aimed to delineate BTC's application in HT, focusing on efficacy, safety, and associated complications at a high-volume HT center. METHODS: A retrospective cohort study was conducted of patients who underwent HT between January 2017 and December 2021 and subsequently received BTC as part of their immunosuppressive regimen. Twenty-one HT recipients were identified. Baseline characteristics, history of rejection, and indication for BTC use were collected. Outcomes included renal function, graft function, allograft rejection and mortality. Follow-up data were collected through December 2023. RESULTS: Among 776 patients monitored from January 2017 to December 2021 21 (2.7%) received BTC treatment. Average age at transplantation was 53 years (± 12 years), and 38% were women. BTC administration began, on average, 689 [483, 1830] days post-HT. The primary indications for BTC were elevated pre-formed donor-specific antibodies in highly sensitized patients (66.6%) and renal sparing (23.8%), in conjunction with reduced calcineurin inhibitor dosage. Only one (4.8%) patient encountered rejection within a year of starting BTC. Graft function by echocardiography remained stable at 6 and 12 months posttreatment. An improvement was observed in serum creatinine levels (76.2% of patients), decreasing from a median of 1.58 to 1.45 (IQR [1.0-2.1] to [1.1-1.9]) over 12 months (p = .054). eGFR improved at 3 and 6 months compared with 3 months pre- BTC levels; however, this was not statistically significant (p = .24). Treatment discontinuation occurred in seven patients (33.3%) of whom four (19%) were switched back to full dose CNI. Infections occurred in 11 patients (52.4%), leading to BTC discontinuation in 4 patients (19%). CONCLUSION: In this cohort, BTC therapy was used as alternative immunosuppression for management of highly sensitized patients or for renal sparing. BTC therapy when combined with CNI dose reduction resulted in stabilization in renal function as measured through renal surrogate markers, which did not, however, reach statistical significance. Patients on BTC maintained a low rejection rate and preserved graft function. Infections were common during BTC therapy and were associated with medication pause/discontinuation in 19% of patients. Further randomized studies are needed to assess the efficacy and safety of BTC in HT recipients.

Long-term outcomes for pediatric heart transplant recipients transitioning to adult care teams.

BACKGROUND: There are limited data evaluating the success of a structured transition plan specifically for pediatric heart transplant (HT) recipients following their transfer of care to an adult specialist. We sought to identify risk factors for poor adherence, graft failure, and mortality following the transfer of care to adult HT care teams. METHODS: We retrospectively reviewed all patients who underwent transition from the pediatric to adult HT program at our center between January 2011 and June 2021. Demographic characteristics, comorbid conditions, and psychosocial history were collected at the time of HT, the time of transition, and the most recent follow-up. Adverse events including mortality, graft rejection, infection, and renal function were also captured before and after the transition. RESULTS: Seventy-two patients were identified (54.1% male, 54.2% Caucasian). Mean age at the time of transition was 23 years after a median of 11.6 years in the pediatric program. The use of calcineurin inhibitors was associated with reduced mortality (HR .04, 95% CI .0-.6, p = .015), while prior psychiatric hospitalization (HR 45.3, 95% CI, 6.144-333.9, p = .0001) was associated with increased mortality following transition. Medication nonadherence and young age at the time of transition were markers for high-risk individuals prior to the transition of care. CONCLUSIONS: Transition of HT recipients from a pediatric program to an adult program occurs during a vulnerable time of emerging adulthood, and we have identified risk factors for mortality following transition. Development of a formalized transition plan with a large multidisciplinary team with focused attention on high-risk patients, including those with psychiatric comorbidities, may favorably influence outcomes.

Hemodynamic Optimization by Invasive Ramp Test in Patients Supported With HeartMate 3 Left Ventricular Assist Device.

In patients supported by the HeartMate 3 left ventricular assist device (HM3 LVAD), pump speed adjustments may improve hemodynamics. We investigated the hemodynamic implications of speed adjustments in HM3 recipients undergoing hemodynamic ramp tests. Clinically stable HM3 recipients who underwent routine invasive hemodynamic ramp tests between 2015 and 2022 at our center were included. Filling pressure optimization, defined as central venous pressure (CVP) <12 mm Hg and pulmonary capillary wedge pressure (PCWP) <18 mm Hg, was assessed at baseline and final pump speeds. Patients with optimized pressures were compared to nonoptimized patients. Overall 60 HM3 recipients with a median age of 62 years (56, 71) and time from LVAD implantation of 187 days (124, 476) were included. Optimized filling pressures were found in 35 patients (58%) at baseline speed. Speed was adjusted in 84% of the nonoptimized patients. Consequently, 39 patients (65%) had optimized pressures at final speed. There were no significant differences in hemodynamic findings between baseline and final speeds (p > 0.05 for all). Six and 12 month readmission-free rates were higher in optimized compared with nonoptimized patients (p = 0.03 for both), predominantly due to lower cardiac readmission-free rates (p = 0.052). In stable outpatients supported with HM3 who underwent routine ramp tests, optimized hemodynamics were achieved in only 2 of 3 of the patients. Patients with optimized pressures had lower all-cause readmission rates, primarily driven by fewer cardiac-related hospitalizations.

Impact of Interventricular Interaction on Ventricular Function: Insights From Right Ventricular Pressure-Volume Analysis.

BACKGROUND: Interventricular interactions may be responsible for the decline in ventricular performance observed in various disease states that primarily affect the contralateral ventricle. OBJECTIVES: This study sought to quantify the impact of such interactions on right ventricular (RV) size and function using clinically stable individuals with left ventricular assist devices (LVADs) as a model for assessing RV hemodynamics while LV loading conditions were acutely manipulated by changing device speed during hemodynamic optimization studies (ie, ramp tests). METHODS: The investigators recorded RV pressure-volume loops with a conductance catheter at various speeds during ramp tests in 20 clinically stable HeartMate3 recipients. RESULTS: With faster LVAD speeds and greater LV unloading, indexed RV end-diastolic volume increased (72.28 ± 15.07 mL at low speed vs 75.95 ± 16.90 at high speed; P = 0.04) whereas indexed end-systolic volumes remained neutral. This resulted in larger RV stroke volumes and shallower end-diastolic pressure-volume relationships. Concurrently, RV end-systolic pressure decreased (31.58 ± 9.75 mL at low speed vs 29.58 ± 9.41 mL at high speed; P = 0.02), but contractility, as measured by end-systolic elastance, did not change significantly. The reduction in RV end-systolic pressure was associated with a reduction in effective arterial elastance from 0.65 ± 0.43 mm Hg/mL at low speed to 0.54 ± 0.33 mm Hg/mL at high speed (P = 0.02). CONCLUSIONS: Interventricular interactions resulted in improved RV compliance, diminished afterload, and did not reduce RV contractility. These data challenge the prevailing view that interventricular interactions compromise RV function, which has important implications for the understanding of RV-LV interactions in various disease states, including post-LVAD RV dysfunction.

A change of heart: Characteristics and outcomes of multiple cardiac retransplant recipients.

BACKGROUND: Among heart transplant (HT) recipients who develop advanced graft dysfunction, cardiac re-transplantation may be considered. A smaller subset of patients will experience failure of their second allograft and undergo repeat re-transplantation. Outcomes among these individuals are not well-described. METHODS: Adult and pediatric patients in the United Network for Organ Sharing (UNOS) registry who received HT between January 1, 1990 and December 31, 2020 were included. RESULTS: Between 1990 and 2020, 90 individuals received a third HT and three underwent a fourth HT. Recipients were younger than those undergoing primary HT (mean age 32 years). Third HT was associated with significantly higher unadjusted rates of 1-year mortality (18% for third HT vs. 13% for second HT vs. 9% for primary HT, p < .001) and 10-year mortality (59% for third HT vs. 42% for second HT vs. 37% for primary HT, p < .001). Mortality was highest amongst recipients aged >60 years and those re-transplanted for acute graft failure. Long-term rates of CAV, rejection, chronic dialysis, and hospitalization for infection were also higher. CONCLUSIONS: Third HT is associated with higher morbidity and mortality than primary HT. Further consensus is needed regarding appropriate organ stewardship for this unique subgroup.

The Hemodynamic Effects of Aortic Regurgitation in Patients Supported by a HeartMate 3 Left Ventricular Assist Device.

BACKGROUND: Aortic regurgitation (AR) is a common complication following left ventricular assist device (LVAD) implantation. We evaluated the hemodynamic implications of AR in patients with HeartMate 3 (HM3) LVAD at baseline and in response to speed changes. METHODS AND RESULTS: Clinically stable outpatients supported by HM3 who underwent a routine hemodynamic ramp test were retrospectively enrolled in this analysis. Patients were stratified based on the presence of at least mild AR at baseline speed. Hemodynamic and echocardiographic parameters were compared between the AR and non-AR groups. Sixty-two patients were identified. At the baseline LVAD speed, 29 patients (47%) had AR, while 33 patients (53%) did not. Patients with AR were older and supported on HM3 for a longer duration. At baseline speed, all hemodynamic parameters were similar between the groups including central venous pressure, pulmonary capillary wedge pressure, pulmonary arterial pressures, cardiac output and index, and pulmonary artery pulsatility index (p > 0.05 for all). During the subacute assessment, AR worsened in some, but not all, patients, with increases in LVAD speed. There were no significant differences in 1-year mortality or hospitalization rates between the groups, however, at 1-year, ≥ moderate AR and right ventricular failure (RVF) were detected in higher rates among the AR group compared to the non-AR group (45% vs. 0%; p < 0.01, and 75% vs. 36.8%; p = 0.02, respectively). CONCLUSIONS: In a cohort of stable outpatients supported with HM3 who underwent a routine hemodynamic ramp test, the presence of mild or greater AR did not impact the ability of HM3 LVADs to effectively unload the left ventricle during early subacute assessment. Although the presence of AR did not affect mortality and hospitalization rates, it resulted in higher rates of late hemodynamic-related events in the form of progressive AR and RVF.

Reverse Remodeling Effects of Sacubitril-Valsartan: Structural and Functional Optimization in Stage C Heart Failure.

Sacubitril-valsartan, an angiotensin receptor-neprilysin inhibitor, reduces all-cause mortality and the rate of heart failure hospitalizations in patients with heart failure with reduced ejection fraction. This study aimed to elucidate the benefits of initiating sacubitril-valsartan on ventricular remodeling in patients previously optimized on guideline-directed medical therapy. In this prospective, single-arm longitudinal study, 40 patients with heart failure with reduced ejection fraction who were optimized on guideline-directed medical therapy were transitioned to sacubitril-valsartan. The primary end point was the change in left ventricular (LV) volume at 1 year as assessed by 3-dimensional transthoracic echocardiography. Other echocardiographic end points included change in LV-function and change in right ventricular (RV) size and function. The mean age was 55 ± 12 years, and 63% were male. At 1 year, LV end-diastolic volume decreased from 242 ± 71 to 157 ± 57 ml (p <0.001) with a corresponding increase in LV ejection fraction from 32 ± 7% to 44 ± 9% (p <0.001). RV end-diastolic volume decreased from 151 ± 51 to 105 ±45 ml (p <0.001). Although RV ejection fraction did not change (51 ± 8 vs 51 ± 10; p = 0.35), RV global longitudinal strain improved from -14.9 ± 3.4 % to -19.3 ± 4.3% (p <0.001). When added to standard medical therapy for heart failure, sacubitril-valsartan induces significant remodeling of both the right and left ventricles as assessed by 3-dimensional echocardiography.

Pumping for Two: Pregnancy in Patients Supported With a Left Ventricular Assist Device.

This review discusses the challenges and outcomes associated with pregnancy during left ventricular assist device (LVAD) support. Women account for a third of the heart failure population in the United States. Left ventricular assist devices have emerged as a safe and effective treatment option for patients with advanced heart failure. Pregnancy during LVAD support can occur, and it presents significant risks to both mother and fetus, including hemodynamic stress, thrombotic events, medication-associated teratogenicity, and uterine impingement. This literature review identified 10 cases of confirmed pregnancy during LVAD support, of which eight resulted in successful births. Maternal and fetal mortality occurred in one case, and there was a spontaneous abortion in one case. The review highlights the importance of a multidisciplinary approach, promotion of shared decision-making, thoughtful anticoagulation, adjustment of LVAD speed, and medication optimization to maintain hemodynamic support during pregnancy. Hemodynamic changes during pregnancy include increased cardiac output, heart rate, and plasma volume, as well as decreased systemic vascular resistance, which can impact LVAD support. Despite reduced pulsatility in LVAD-supported patients, ovulation and reproductive capacity might be preserved, and viable pregnancies may be achieved with appropriate management. The review provides insights into the risks and considerations for a viable pregnancy during LVAD support, including the need for ongoing research to inform joined decision-making.

The utilization of molecular microscope in management of heart transplant recipients in the era of noninvasive monitoring.

INTRODUCTION: Monitoring for graft rejection is a fundamental tenet of post-transplant follow-up. In heart transplantation (HT) in particular, rejection has been traditionally assessed with endomyocardial biopsy (EMB). EMB has potential complications and noted limitations, including interobserver variability in interpretation. Additional tests, such as basic cardiac biomarkers, cardiac imaging, gene expression profiling (GEP) scores, donor-derived cell-free DNA (dd-cfDNA) and the novel molecular microscope diagnostic system (MMDx) have become critical tools in rejection surveillance beyond standard EMB. METHODS: This paper describes an illustrative case followed by a review of MMDx within the context of other noninvasive screening modalities for rejection. CONCLUSIONS: We suggest MMDx be used to assist with early detection of rejection in cases of discordance between EMB and other noninvasive studies.

Aortic Root Thrombosis in patients with HeartMate 3 left ventricular assist device support.

BACKGROUND: Aortic root thrombosis(ART) is a complication of continuous-flow left ventricular assist device therapy. However, the incidence and related complications of ART in HeartMate 3 (HM3) patients remain unknown. METHODS: Patients who underwent HM3 implantation from November 2014 to August 2020 at a quaternary academic medical center were included. Demographics and outcomes were abstracted from the medical record. Echocardiograms and contrast-enhanced computed tomography studies were reviewed to identify patients who developed ART and/or moderate or greater aortic insufficiency (AI) on HM3 support. RESULTS: The study cohort included 197 HM3 patients with a median postimplant follow-up of 17.5 months. Nineteen patients (9.6%) developed ART during HM3 support, and 15 patients (7.6%) developed moderate or greater AI. Baseline age, gender, race, implantation strategy, and INTERMACS classification were similar between the ART and no-ART groups. ART was associated with an increased risk of death, stroke, or aortic valve (AV) intervention (subhazard ratio [SHR] 3.60 [95% confidence interval (CI) 1.71-7.56]; p = 0.001) and moderate or greater AI (SHR 11.1 [CI 3.60-34.1]; p < 0.001) but was not associated with a statistically significantly increased risk of death or stroke on HM3 support (2.12 [0.86-5.22]; p = 0.10). Of the 19 patients with ART, 6 (31.6%) developed moderate or greater AI, necessitating more frequent AV interventions (ART: 5 AV interventions [3 surgical repairs, 1 surgical replacement, 1 transcatheter replacement; 26.3%]; no-ART: 0). CONCLUSIONS: Nearly 10% of HM3 patients developed ART during device support. ART was associated with increased risk of a composite end-point of death, stroke, or AV intervention as well as moderate or greater AI.

New system, old problem: Increased wait time for high-priority transplant candidates.

The 2018 heart allocation policy sought to improve risk stratification and reduce waitlist mortality for the sickest patients. This study sought to evaluate changes in wait times for the highest priority patients since policy implementation. All adult single-organ transplant recipients were identified in the United Network for Organ Sharing registry from October 18, 2018, to July 8, 2022, and separated into 4 periods. Outcomes were compared by blood type and UNOS region. Over the study period, 897 of 9,143 patients were listed as status 1 with no significant change in median wait time by blood type or region. More patients were listed as status 2 (4,523/9,143), and each subsequent period postpolicy change was associated with a 4.2-day increase in mean status 2 waitlist time (95% confidence interval 3.0-5.5, p < 0.0001). Wait times were longest for candidates with blood type O and shortest for AB & A. Regional variations continued, however, wait time increased in every region over time.

Impact of preheart transplant spirometry and DCLO measurement on post-transplant pulmonary outcomes.

BACKGROUND: Pulmonary function tests (PFT) are a frequent component of heart transplant evaluation. In cardiac surgery abnormal PFTs, especially reduced DLCO, have been associated with poor outcomes. We sought to evaluate the impact of pretransplant PFTs on post-transplant pulmonary outcomes and patient survival. METHODS: Among the 652 adult heart transplant recipients between January 1, 2010 and July 31, 2021, 462 had PFTs and constituted the patient cohort. Obstructive ventilatory defects (OVD), restrictive ventilatory defects (RVD), and reduced DLCO were defined according to established criteria. The primary outcome was the combined endpoint of a post-transplant pulmonary complication defined as reintubation, postoperative pneumonia, prolonged intubation, or tracheostomy. Secondary outcomes included 90-day all-cause mortality, length of stay, and the odds of individual pulmonary complications. Kaplan-Meier survival analysis, multivariable Cox proportional-hazards regression, and multivariable logistic regression were performed to compare outcomes between the groups. RESULTS: Patients with severe OVD (OR 1.48, 95% CI 1.18-5.23, p = 0.02) or severely reduced DLCO (OR 1.95, 95% CI 1.19-3.20, p = 0.008) had increased odds of post-transplant pulmonary complications. Following multivariable adjustment, severe OVD (aOR 2.67, 95% CI 1.15-6.19, p = 0.02) and severely reduced DLCO (aOR 1.79, 95% CI 1.05-3.04) remained strongly associated with post-transplant pulmonary complications. Patients with any degree of extrinsic RVD, moderate or less OVD, or moderately reduced DLCO or less did not have increased odds of post-transplant pulmonary complications. Ninety-day post-transplant survival was significantly reduced for both severe OVD (97.2% vs 86.5%, p = 0.04) and severely reduced DLCO (97.3% vs 90.4%, p = 0.004). Post-transplant ICU and hospital length of stay were nominally longer for both groups as well. CONCLUSIONS: Severe OVD or severely reduced DLCO on preheart transplant PFTs were associated with increased odds of post-transplant pulmonary complications and early mortality.

Early post-transplant leukopenia in heart transplant recipients and its impact on outcomes.

BACKGROUND: Leukopenia in the early period following heart transplantation (HT) is not well-studied. The aim of this study was to evaluate risk factors for the development of post-transplant leukopenia and its consequences for HT recipients. METHODS: Adult patients at a large-volume transplant center who received HT between January 1, 2010 and December 31, 2020 were included. The incidence of leukopenia (WBC ≤3 × 103 /µL) in the first 90-days following HT, individual risk factors, and its effect on 1-year outcomes were evaluated. RESULTS: Of 506 HT recipients, 184 (36%) developed leukopenia within 90-days. Median duration of the first leukopenia episode was 15.5 days (IQR 8-42.5 days). Individuals who developed leukopenia had lower pre-transplant WBC counts compared to those who did not (6.1 × 103 /µL vs. 6.9 × 103 /µL, p = .02). Initial immunosuppressive and infectious chemoprophylactic regimens were not significantly different between groups. Early leukopenia was associated with a higher mortality at 1-year (6.6% vs. 2.1%, p = .008; adjusted HR 3.0) and an increased risk of recurrent episodes. Rates of infection and rejection were not significantly different between the two groups. CONCLUSIONS: Leukopenia in the early period following HT is common and associated with an increased risk of mortality. Further study is needed to identify individuals at highest risk for leukopenia prior to transplant and optimize immunosuppressive and infectious chemoprophylactic regimens for this subgroup.

Outflow Graft Narrowing of the HeartMate 3 Left Ventricular Assist Device.

BACKGROUND: In patients with the HeartMate 3 (HM3, Abbott) left ventricular (LV) assist device (LVAD), outflow graft narrowing has been reported as a result of accumulation of biodebris either internal or external to the graft. This study describes the prevalence, imaging findings, and clinical outcomes associated with HM3 LVAD outflow graft narrowing. METHODS: A single-center retrospective cohort study was performed in patients who received an HM3 LVAD between November 2014 and July 2019. All patients with a computed tomographic (CT) angiogram or a CT scan with intravenous contrast sufficient to evaluate the outflow graft lumen were included. Narrowing was defined as a hypodensity of ≥3 mm. RESULTS: Of 165 HM3 LVAD recipients, 46 (28%) had qualifying imaging. Outflow graft narrowing was present in 33% (15/46). One patient had complete obstruction requiring emergency surgery, whereas 14 patients had a median hypodensity of 4.5 mm (interquartile range, 3.3-5.8 mm). The presence of outflow graft narrowing was significantly associated with a longer duration of LVAD support (588.2 ± 277.5 days vs 131.5 ± 170.9 days; P < .0001). One-year survival after identification of narrowing was 93%, with death occurring in 1 patient with complete obstruction. LV unloading (mean percent decrease in LV end-diastolic diameter at time of CT imaging vs pre-LVAD) was 16.7% vs 17.7% in patients with and without narrowing, respectively (P = .86). CONCLUSIONS: Among patients with adequate imaging, one-third have evidence of narrowing. Outflow graft narrowing secondary to biodebris was more likely to be found in HM3 LVAD recipients with longer duration of LVAD support. There was no significant difference in LV unloading between patients with and without narrowing.

Large pulmonary artery pseudoaneurysm after CardioMEMS implantation: a case report.

Background: CardioMEMS heart failure (HF) system is an implantable wireless pressure sensor that is placed in a branch of the pulmonary artery (PA) for remote monitoring of PA pressures in patients with HF. Pulmonary artery injury/haemoptysis can occur during the sensor placement. Case summary: An 80-year-old male patient with HF with reduced ejection fraction (20%) underwent CardioMEMS HF system implantation for recurrent shortness of breath. He developed haemoptysis and dyspnoea during the procedure, which was managed with furosemide. The patient's computerized tomographic angiography showed a 3.4 cm pseudoaneurysm with active extravasation from the superior segmental branch of the left PA due to injury during device placement. The decision to embolize the pseudoaneurysm was made after a multi-disciplinary team meeting and discussion with the patient. The embolization procedure was carried out successfully with the final left pulmonary angiogram showed complete stasis and no further filling of the pseudoaneurysm sac. Discussion: The incidence of mortality in patients with PA injury from CardioMEMS devices is high, and therefore prompt diagnosis and management are critical. Pulmonary artery pseudoaneurysms are uncommon and present with haemoptysis. Transcatheter embolization has been shown to be a practical, effective, and safe therapeutic option in stable patients.

Continuous Monitoring of Blood Pressure Using a Wrist-Worn Cuffless Device.

BACKGROUND: Measuring an accurate blood pressure (BP) in ambulatory patients is critical for therapeutic decisions. An accurate noninvasive device that measures BP continuously could provide a more comprehensive assessment of BP. The aim of this study was to determine whether the LiveOne device, a cuffless wristband that provides continuous BP measurements, is accurate in comparison to an invasive arterial line (A-line). METHODS: We enrolled hospitalized patients and healthy volunteers in this multicenter study. All patients had an invasive A-line. Waveforms were simultaneously downloaded from the A-line and LiveOne device. The primary outcome was the correlation between the LiveOne device and the A-line for systolic BP (SBP) and diastolic BP (DBP). RESULTS: Thirty-four patients with 233 measurement periods were included. Mean age was 60.7 ± 15.2 years, and 15 (44%) were female. The correlation for SBP was 0.91 and for DBP was 0.85. The mean band error was 0.0 ± 6.9 mm Hg for SBP and 1.2 ± 5.7 mm Hg for DBP. The mean absolute error was 8.2 ± 5.8 mm Hg for SBP and 6.4 ± 3.9 mm Hg for DBP. For SBP, 98% of LiveOne measurements were within 15 mm Hg and for DBP, 92% of LiveOne measurements were within 10 mm Hg. CONCLUSIONS: The LiveOne device provides continuous, noninvasive BP measurements that are accurate in comparison to A-line measurements. The portability and unobtrusive nature of this device and the ability to provide continuous BP measurements may offer advantages over currently available BP monitors. CLINICAL TRIALS REGISTRATION: Trial Number NCT03919136.

Impact of Temporary Percutaneous Mechanical Circulatory Support Before Transplantation in the 2018 Heart Allocation System.

OBJECTIVES: This analysis sought to investigate the waitlist and post-transplant outcomes of individuals bridged to transplantation by using temporary percutaneous endovascular mechanical circulatory support (tMCS) through a status 2 designation (cardiogenic shock and exception). BACKGROUND: The 2018 donor heart allocation policy change granted a status 2 designation to patients supported with tMCS. METHODS: Adult patients in the United Network for Organ Sharing registry after October 18, 2018 who received a status 2 designation for tMCS were included and grouped by their status 2 criteria: cardiogenic shock with hemodynamic criteria (CS-HD), cardiogenic shock without hemodynamic criteria before tMCS (CS-woHD), and exception. Baseline characteristics, waitlist events (death and delisting), and post-transplant outcomes were compared. RESULTS: A total of 2,279 patients met inclusion criteria: 68.6% (n = 1,564) with CS-HD, 3.2% (n = 73) with CS-woHD, and 28.2% (n = 642) with exceptions. A total of 64.2% of patients underwent heart transplantation within 14 days of status 2 listing or upgrade, and 1.9% died or were delisted for worsening clinical condition. Among the 35.8% who did not undergo transplantation following 14 days, only 2.8% went on to receive a left ventricular assist device (LVAD). The 30-day transplantation likelihood was similar among groups: 80.1% for the CS-HD group vs 79.7% for the exception group vs 73.3% for the CS-woHD group; P = 0.31. However, patients who met criteria for CS-woHD had 2.3-fold greater risk of death or delisting (95% CI: 1.10-4.75; P = 0.03) compared with CS-HD patients after multivariable adjustment. Pre-tMCS hemodynamics were not associated with adverse waitlist events. CONCLUSIONS: The use of tMCS is an efficient, safe, and effective strategy as a bridge to transplantation; however, patients with CS-woHD may represent a high-risk cohort. Transition to a durable LVAD was a rare event in this group.

Surveillance for disease progression of transthyretin amyloidosis after heart transplantation in the era of novel disease modifying therapies.

BACKGROUND: Heart Transplantation (HT) is a rational therapy for advanced transthyretin cardiac amyloidosis (ATTR-CA), but the impact of ongoing amyloid deposition is not well defined. We evaluated a cohort of patients who underwent HT for ATTR-CA to determine the incidence of de novo or progression of post-HT ATTR deposition. METHODS: All patients who were followed post-HT for ATTR-CA at our center were included. Baseline demographics and post-HT manifestations of TTR deposition were collected. All patients completed the Composite Autonomic Symptom Score (COMPASS-31 quantifies autonomic symptoms, with a higher score [0-100] indicating more severe autonomic dysfunction) and Polyneuropathy Disability Score (PND, range from 0 [asymptomatic] to IV [confined to wheelchair/bed]) questionnaires. RESULTS: Twelve patients (5 wild-type, 7 variant [6 p.Val142Ile, 1 p.Thr80Ala]) were included. Mean age at HT was 64.6 (SD: 4.8) years, 83.3% male, and 50% Black. At a median of 4.0 years (IQR 2.4, 5.9) post-HT, 8 patients had symptoms of ATTR deposition (5 with gastrointestinal involvement, 4 orthopedic and 4 neurologic), with 4 patients having ≥2 body systems involved. There were no patients with recurrent cardiac involvement. Median COMPASS-31 score was 17.3 (IQR 11.3, 23.5) at 3.9 years (IQR 2.4, 5.9) post-HT. Four patients had a PND score of stage 1 (sensory disturbance), 1 patient was stage 2 (impaired walking) and 1 patient stage 3b (required a walking aid). CONCLUSIONS: More than 50% of patients had evidence of progressive or de novo ATTR deposition post-HT, impairing quality of life despite a well-functioning cardiac allograft. These observations highlight an unmet need to establish the role of formal surveillance and treatment of TTR using TTR disease-modifying therapies, which may maintain or improve quality of life post-HT for ATTR-CA.