A heart transplant center experience with basiliximab induction strategies: A double edged sword?

BACKGROUND: The use of induction immunosuppression for heart transplantation (HT) is debated given the uncertain benefit and potential risks of infection and malignancy. METHODS: This is a retrospective single-center analysis of 475 consecutive HT recipients from 2003 to 2020 grouped by use of induction with basiliximab group (BG) and the no basiliximab group (NBG). Subgroup analysis by era compared pre-2016 standard-basiliximab (BX) induction and 2016-2020 with selective-BX use as part of a calcineurin-inhibitor-sparing regimen. RESULTS: When adjusted for confounders (sex, age, PRA, eGFR), the BG was less likely to have acute cellular rejection (ACR) (OR.42, p < .001), but had more antibody mediated rejection (AMR) (OR 11.7, p < .001) and more cardiac allograft vasculopathy (CAV) (OR 3.8, p = .04). There was no difference between BG and NBG in the incidence of malignancies or infections. When stratified by era (pre-2016 vs. 2016-2020), ACR remained less common in the BG than the NBG (36% vs. 50%, p = .045) groups, while AMR remained more common (9.7 vs. 0% p = .005). There was no significant difference in conditional survival comparing pre-and post-2016 NBG (HR 2.20 (95% CI.75-6.43); however, both pre-2016 BG and post-2016 BG have significantly higher mortality (HR 2.37 [95% CI 1.02-5.50) and HR 2.69 (95% CI 1.08-6.71), p = .045 and.03, respectively]. CONCLUSION: Basiliximab reduces the incidence of ACR but increases the risk of AMR, CAV, and may be associated with increased mortality. Mechanistic studies are needed to describe a potential T-cell-escape mechanism with enhanced humoral immunity.

Potential clinical utility of 68Ga-DOTATATE PET/CT for detection and response assessment in cardiac sarcoidosis.

BACKGROUND: Somatostatin receptor is expressed in sarcoid granulomas, and preliminary clinical studies have shown that myocardial sarcoidosis can be identified on somatostatin receptor-targeted PET. We examined the potential clinical use of 68Ga-DOTATATE PET/CT for diagnosis and response assessment in cardiac sarcoidosis compared to 18F-FDG PET/CT. METHODS: Eleven cardiac sarcoidosis patients with 18F-FDG PET/CT were prospectively enrolled for cardiac 68Ga-DOTATATE PET/CT. The two PET/CT studies were interpreted independently and were compared for patient-level and segment-level concordance, as well as for the degree of radiotracer uptake. Follow-up 68Ga-DOTATATE PET/CT was performed in eight patients. RESULTS: Patient-level concordance was 91%: ten patients had multifocal DOTATATE uptake (active cardiac sarcoidosis) and one patient showed diffuse DOTATATE uptake. Segment-level agreement was 77.1% (Kappa 0.53 ± 0.07). The SUVmax-to-blood pool ratio was lower on 68Ga-DOTATATE PET/CT (3.2 ± 0.6 vs. 4.9 ± 1.5, P = 0.006 on paired t test). Follow-up 68Ga-DOTATATE PET/CT showed one case of complete response and one case of partial response, while 18F-FDG PET/CT showed four cases of response, including three with complete response. CONCLUSION: Compared to 18F-FDG PET/CT, 68Ga-DOTATATE PET/CT can identify active cardiac sarcoidosis with high patient-level concordance, but with moderate segment-level concordance, low signal-to-background ratio, and underestimation of treatment response.

Effect of Immunosuppressive Therapy and Biopsy Status in Monitoring Therapy Response in Suspected Cardiac Sarcoidosis.

BACKGROUND: Patients with suspected cardiac sarcoidosis frequently undergo fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) imaging to assess disease activity at baseline and after treatment initiation. OBJECTIVES: This study investigated the effect of immunosuppressive therapy and biopsy status to achieve complete treatment response (CTR), partial treatment response (PTR), or no response (NR) on myocardial FDG-PET/CT. METHODS: This study analyzed 83 patients with suspected cardiac sarcoidosis (aged 53 ± 1.8 years, 71% were male, 69% were White, 61% had a history of biopsy-confirmed sarcoidosis) who were treatment naive, had evidence of myocardial FDG at baseline, and underwent repeat PET imaging after treatment initiation. CTR was graded visually, and PTR/NR were measured both visually and quantitatively using the total glycolytic activity. Patients were also evaluated for the occurrence of death, sustained ventricular arrhythmias, and heart failure admissions. RESULTS: Overall, 59 patients (71%) achieved CTR/PTR (30%/41%) at follow-up scan (P = 0.04). Total glycolytic activity and visual estimate of PTR/NR had excellent agreement (κ = 0.86 [95% CI: 0.72-0.99]; P < 0.0001). In patients receiving prednisone only, the highest rates of CTR/PTR were observed in patients initiated on moderate or high dose (P < 0.01). In a regression model, moderate prednisone start dose (P = 0.03) was more strongly associated with achieving CTR/PTR than was high prednisone start dose. However, the latter patients were tapered faster between start dose and follow-up scan (P < 0.01). After a median follow-up of 4.7 (IQR: 3.1-7.8) years, patients who were biopsy-proven (vs non-biopsy-proven; P = 0.029) and with preserved left ventricular function (P = 002) were less likely to experience major adverse cardiac events. Outcomes based on treatment response status (CTR vs PTR vs NR; P = 0.23) were not significantly different. CONCLUSIONS: Among patients with suspected sarcoidosis and evidence of myocardial inflammation, treatment response by serial FDG-PET was variable, but a favorable response was more common when using moderate-to-high intensity prednisone dose. Biopsy-proven individuals and those with preserved systolic function were less likely to experience adverse outcomes during follow-up.

Safety and Effectiveness of Intravenous Iron Therapy in Patients Supported by Durable Left Ventricular Assist Devices.

AIMS: While it is common practice to use intravenous (IV) iron in patients with left ventricular assist devices (LVADs) and iron deficiency, there is insufficient evidence regarding outcomes in this patient population. We evaluated the safety and effectiveness of IV iron therapy in patients supported by LVADs with iron deficiency. METHODS: We performed a retrospective analysis of iron deficient patients on continuous LVAD support at a large academic center between 2008 and 2019. Patients were divided into two cohorts based on IV iron sucrose treatment. The primary endpoint was hemoglobin at 12 weeks. Secondary endpoints were mean corpuscular volume (MCV) and New York Heart Association (NYHA) class at 12 weeks. Safety endpoints included hospitalization, infection, pump thrombosis, arrhythmia, and gastrointestinal bleed. Models were weighted by the inverse probability of receiving IV iron using a propensity score, and endpoints were adjusted for their corresponding baseline values. RESULTS: Among 213 patients, 70 patients received IV iron and 143 patients did not. Hemoglobin at 12 weeks was significantly greater among those treated (intergroup difference: 0.6 g/dL; 95% CI, 0.1 to 1.1; p = 0.01), while MCV was similar in both groups (intergroup difference: 0.7 µm3; 95% CI, -1.3 to 2.7; p = 0.50). NYHA class distribution at 12 weeks was significantly different (odds ratio for improvement: 2.84; 95% CI, 1.42 to 4.68; p = 0.003). The hazards of adverse events in each group were similar. CONCLUSIONS: In patients with LVADs and iron deficiency, treatment with IV iron sucrose was safe and associated with improvements in functional status and hemoglobin.

Characteristics and Outcomes of Candidemia in Patients with Durable Left Ventricular Assist Device Support.

There are limited data on the characteristics and clinical course of fungal infections in patients on durable left ventricular assist device (LVAD) support. We sought to further characterize the epidemiology and outcomes of LVAD patients with fungemia. We performed a retrospective review of patients receiving LVAD support from January 2012 through June 2020 at a large academic institution. Among 336 patients on LVAD support, five (1.4%) were diagnosed with fungemia during the study period. Three patients had diabetes with mean hemoglobin A1c 7.1% (R 6.6, 7.4). Fever and leukocytosis (mean white blood count 17.0 thousand/µL [R 12.5, 29.9]) were the most common symptoms. Fungemia was diagnosed early after LVAD implantation (mean 14.4 support days [R 2, 19]). All patients were infected with Candida species, and four isolates were susceptible to fluconazole. Central nervous system outcomes included an ischemic stroke, subarachnoid hemorrhage, and malignant hemorrhagic stroke. Two patients were successfully transplanted, and two patients on destination therapy remain on suppressive fluconazole. In conclusion, fungemia is a rare and severe complication in LVAD patients occurring early postimplant.

Cardiopulmonary Exercise Testing-A Valuable Tool, Not Gatekeeper When Referring Patients With Adult Congenital Heart Disease for Transplant Evaluation.

INTRODUCTION: Treatment of patients with adult congenital heart disease (ACHD) with advanced therapies including heart transplant (HT) is often delayed due to paucity of objective prognostic markers for the severity of heart failure (HF). While the utility of Cardiopulmonary Exercise Testing (CPET) in non-ACHD patients has been well-defined as it relates to prognosis, CPET for this purpose in ACHD is still under investigation. METHODS: We performed a retrospective cohort study of 20 consecutive patients with ACHD who underwent HT between March 2010 and February 2016. Only 12 of 20 patients underwent CPET prior to transplantation. Demographics, standard measures of CPET interpretation, and 30-day and 1-year post transplantation outcomes were collected. RESULTS: Patient Characteristics. Twenty patients with ACHD were transplanted at a median of 40 years of age (range: 23-57 years). Of the 12 patients who underwent CPET, 4 had undergone Fontan procedures, 4 had tetralogy of Fallot, 3 had d-transposition of the great arteries, and 1 had Ebstein anomaly. Thirty-day and one-year survival was 100%. All tests included in the analysis had a peak respiratory quotient _1.0. The median peak oxygen consumption per unit time (_VO2) for all diagnoses was 18.2 mL/kg/min (46% predicted), ranging from 12.2 to 22.6. CONCLUSION: There is a paucity of data to support best practices for patients with ACHD requiring transplantation. While it cannot be proven based on available data, it could be inferred that outcomes would have been worse or perhaps life sustaining options unavailable if providers delayed referral because of the lack of attainment of CPET-specific thresholds.

Variables of importance in the Scientific Registry of Transplant Recipients database predictive of heart transplant waitlist mortality.

The prelisting variables essential for creating an accurate heart transplant allocation score based on survival are unknown. To identify these we studied mortality of adults on the active heart transplant waiting list in the Scientific Registry of Transplant Recipients database from January 1, 2004 to August 31, 2015. There were 33 069 candidates awaiting heart transplantation: 7681 UNOS Status 1A, 13 027 Status 1B, and 12 361 Status 2. During a median waitlist follow-up of 4.3 months, 5514 candidates died. Variables of importance for waitlist mortality were identified by machine learning using Random Survival Forests. Strong correlates predicting survival were estimated glomerular filtration rate (eGFR), serum albumin, extracorporeal membrane oxygenation, ventricular assist device, mechanical ventilation, peak oxygen capacity, hemodynamics, inotrope support, and type of heart disease with less predictive variables including antiarrhythmic agents, history of stroke, vascular disease, prior malignancy, and prior tobacco use. Complex interactions were identified such as an additive risk in mortality based on renal function and serum albumin, and sex-differences in mortality when eGFR >40 mL/min/1.73 m. Most predictive variables for waitlist mortality are in the current tiered allocation system except for eGFR and serum albumin which have an additive risk and complex interactions.

Interaction of Donor and Recipient Age: Do Older Heart Transplant Recipients Require Younger Hearts?

BACKGROUND: Older patients (aged 60 years or more) awaiting heart transplant often have comorbidities that may limit overall survival independent of cardiac status. We hypothesized that these comorbidities have a more-limiting impact on survival than age of donor heart and that older allografts might be utilized in these patients without compromising outcomes. METHODS: We identified all transplant recipients aged more than 60 years in the United Network for Organ Sharing database. Local regression analysis detected the point above which increasing donor age incurred increasing risk of mortality, above and below which two cohorts were defined. Kaplan-Meier analysis compared cumulative 5-year survival between groups. Cox proportional hazard modeling was then used to determine the hazards of death in the two groups. RESULTS: An inflection point in posttransplant survival was detected near donor age 50 years. Of 14,113 older recipients studied, 86% received younger donor hearts (less than 50 years of age), and 14% received advanced age allografts (50 years of age or more). Baseline characteristics were comparable between groups except more recipients had left ventricular assist devices at time of transplant in the younger donor group (15% versus 9%, p < 0.001). Five-year survival was significantly lower among recipients receiving advanced age hearts compared with those receiving younger hearts (67% versus 73%, log rank p < 0.001). Adjusting for relevant recipient baseline characteristics, patients receiving advanced age hearts were 30% more likely to die by 5 years compared with patients receiving younger hearts. CONCLUSIONS: Transplant recipients aged 60 years and more who receive advanced age donor hearts (50 years or more) have a significantly increased risk of mortality. With careful allograft selection, use of donor hearts to age 50 may be acceptable among older transplant recipients.

The changing face of adult posttransplant lymphoproliferative disorder: Changes in histology between 1999 and 2013.

Posttransplant lymphoproliferative disorder (PTLD) typically presents with either polymorphic or monomorphic histology. While both are the end result of immunosuppressive therapies, their origins are felt to be different with different prognoses and responsiveness to therapy, resulting in 2 different malignancies. We attempted to confirm reports suggesting that the relative frequency of these 2 histologies is shifting over time. We analyzed 3040 adult PTLD cases in the UNOS OPTN database from 1999 to 2013. Changes in PTLD cases over time were analyzed for histology, time from transplant to diagnosis, and patient EBV serostatus. We found that the relative proportion of polymorphic versus monomorphic histology has changed with an increase in the proportion of monomorphic cases with time (1999-2003, 54.9% vs. 45.1%; 2004-2008, 58.3% vs. 41.7%; 2009-2013, 69.7% vs. 30.3%; P = <.001). The change is driven by a gradual increase in the number of monomorphic PTLD with a steady number of polymorphic PTLD. The change is most strongly seen in transplant recipients who were EBV serostatus positive at the time of transplant. Potential causes are changes in immunosuppressive regimens with increased tacrolimus use (P = .009) and increased survival among transplant patients leading to later occurrence of PTLD (P = .001) that have occurred during the time frame analyzed. As organ transplantation has evolved over time, PTLD has coevolved. These changes in histology have important implications regarding the origin and clinical management of PTLD.

Single-center outcomes of combined heart and liver transplantation in the failing Fontan.

Long-term outcomes of the Fontan operation include Fontan failure and liver disease. Combined heart-liver transplantation (CHLT) is an option for select patients although limited data exist on this strategy. A retrospective review of Fontan patients 18 years or older referred for cardiac transplant evaluation between 2000 and 2013 at the Hospital of the University of Pennsylvania was performed. All patients were considered for potential CHLT. Clinical variables such as demographics, perioperative factors, and short-term outcomes were reviewed. Of 17 referrals for cardiac transplantation, seven Fontan patients underwent CHLT. All patients who underwent CHLT had either advanced fibrosis or cirrhosis on liver biopsy. There were no perioperative deaths. The most common postoperative morbidity was acute kidney injury. Short-term complications include one episode of acute liver rejection but no cardiac rejection greater than 1R. CHLT is an acceptable therapeutic option for patients with failing Fontan physiology who exhibit concomitant advanced liver fibrosis. However, optimal patient selection is currently undefined, and long-term outcomes are not known.

Implementation of a Computerized Order Entry Tool to Reduce the Inappropriate and Unnecessary Use of Cardiac Stress Tests With Imaging in Hospitalized Patients.

The rising use of imaging cardiac stress tests has led to potentially unnecessary testing. Interventions designed to reduce inappropriate stress testing have focused on the ambulatory setting. We developed a computerized order entry tool intended to reduce the use of imaging cardiac stress tests and improve appropriate use in hospitalized patients. The tool was evaluated using preimplementation and postimplementation cohorts at a single urban academic teaching hospital. All hospitalized patients referred for testing were included. The co-primary outcomes were the use of imaging stress tests as a percentage of all stress tests and the percentage of inappropriate tests, compared between the 2 cohorts. There were 478 patients in the precohort and 463 in the postcohort. The indication was chest pain in 66% and preoperative in 18% and was not significantly different between groups. The use of nonimaging stress tests increased from 4% in the pregroup to 15% in the postgroup (p <0.001). Among very low-risk chest pain patients, the use of nonimaging stress tests increased from 7% to 25% (p <0.001). Inappropriate testing did not change significantly between groups (12% vs 11%). Inappropriate tests were most often preoperative evaluations (83%). In conclusion, our computerized ordering tool significantly increased the use of nonimaging cardiac stress tests and reduced the use of imaging tests yet was not able to reduce inappropriate use. Our study highlights the differences in cardiac stress testing between hospitalized and ambulatory patients.

Transplantation of "high-risk" donor hearts: Implications for infection.

BACKGROUND: Heart transplantation is the gold-standard treatment for end-stage heart failure. Short- and long-term outcomes have been excellent, but the shortage of organs persists. The number of potential recipients who die while awaiting orthotopic heart transplantation increases yearly. In 2004, the label "high-risk donor" (HRD) was applied, by the United Network for Organ Sharing (UNOS), to any organ donor who met the Centers for Disease Control (CDC) criteria for behavior that put them at high risk of infection. Despite organ shortages, grafts from HRD CDCs are often declined, because of concerns regarding infection. We undertook this study to analyze our extensive experience with orthotopic heart transplantation of grafts from HRD CDCs, and to determine the short- and long-term outcomes associated with recipients of hearts from HRD CDCs, particularly transmission of infection. METHODS: We performed 367 heart transplantations at our center from September 2008 to September 2014, a timeframe during which the HRD CDC labeling had been implemented. Of the total number of orthotopic heart transplantations performed, 55 patients (15%) received organs from HRD CDCs that had known negative serology for human immunodeficiency virus (HIV), hepatitis B, and hepatitis C. We reviewed demographic, perioperative, and short- and long-term outcomes. The recipients of grafts from HRD CDCs were followed closely, with 3- and 12-month surveillance laboratory testing of viral load for HIV, for hepatitis B, and for hepatitis C core- and surface-antigen serology. RESULTS: All 55 patients (72.7% were men) underwent a successful transplantation procedure. One patient was excluded from follow-up analysis because he was re-transplanted within 4 days owing to the posttransplant finding of metastatic lung adenocarcinoma within the donor. Primary etiology of heart failure was ischemic in 18 of the patients. The most common blood type was O positive, in 20 patients (37.1%), followed by A positive, in 19 patients (35.2%). A total of 19 (35.2%) patients were supported with a mechanical assist device before the transplantation. The average allograft ischemic time was 173 ± 96 minutes. The median length of hospital stay was 19.5 days. A low incidence was observed of the postoperative complications of stroke (1.9%), dialysis (3.9%), and complete heart block (3.9%). Kaplan-Meier analysis demonstrated excellent survival, both short-term (1 year; 94%) and long-term (3 years; 80%). Allograft function was excellent at time of discharge with a left ejection fraction of 67.8% ± 7.3%. Only one patient (1.9%) was noted to have hepatitis C seroconversion at 105 days after receiving the transplant. After antiviral treatment, the patient has had undetectable viral loads to date. All other patients had undetectable plasma viral loads of HIV, hepatitis C, and hepatitis B, determined using rigorous testing. CONCLUSIONS: We present the only single-center series on recipients of heart transplants from HRD CDCs. This potential source of suitable donor organs is shown to lead to excellent survival, without an increased incidence of perioperative or postoperative complications. Furthermore, the risk of transmission of infection from donors in this subgroup seems to be minimal.

Comparison of Causes of Death After Heart Transplantation in Patients With Left Ventricular Ejection Fractions ≤35% Versus >35.

Sudden cardiac death (SCD) is a common cause of death in the general population, occurring in 300,000 to 350,000 people in the United States alone. Currently, there are no data supporting implantable cardioverter-defibrillator therapy in patients who underwent orthotopic heart transplant (OHT) with low left ventricular ejection fraction (LVEF). In this retrospective study, we included all patients who underwent primary OHT at our institution from 2007 to 2013. We compared the cause of death in patients who underwent OHT and evaluated the correlation of the cause of death and the patients' LVEF. Our objectives were to determine whether patients who underwent OHT with LVEF <35% are at increased risk for SCD compared with those who underwent OHT with normal LVEF. To summarize our results, a total of 345 patients were included in our study (mean age 50 ± 14 years, 68% men). The mean follow-up was 1,260 ± 698 days. Forty patients (11.5%) died >6 months after OHT. Surviving patients had higher LVEF compared with deceased patients (64 ± 7% and 50 ± 24%, respectively, p ≤0.001). In all, 10 (25%) of the deceased patients died suddenly, 9 (23%) from sepsis, and 8 (20%) from malignancy. Of the 11 deceased patients with LVEF ≤35%, 2 patients (18%) died suddenly compared with 9 SCDs among the 29 deceased patients (31%) with LVEF >35% (p = 0.54). In conclusion, patients who underwent OHT who died were more likely to have LVEF <35%, and a quarter of the deceased patients who underwent OHT died suddenly. A reduced LVEF was not associated with an increased risk of SCD.

Correlation of Circulating Complement-Fixing Donor-Specific Antibodies Identified by the C1q Assay and Presence of C4d in Endomyocardial Biopsy Specimens.

OBJECTIVES: Donor-specific antibodies (DSAs) are associated with increased cardiac graft loss. We applied a C1q solid-phase assay in parallel with the standard immunoglobulin G (IgG) single antigen bead (SAB) assay to examine the correlation of circulating complement-fixing donor-specific antibodies and the presence of C4d in endomyocardial biopsy (EMB) specimens. METHODS: We retrospectively studied the relationship of C1q+ DSAs and C4d immunofluorescence (IF) in 49 EMB specimens from 44 heart transplant recipients who had concurrent EMB, C4d IF, and DSA measurements. We applied a C1q SAB in parallel with the standard IgG SAB assay to examine the DSA profiles in heart transplant patients posttransplant. RESULTS: A better concordance is observed between C1q+ DSAs with C4d IF+ compared with IgG DSAs with C4d IF + (40% vs 24%, P = .02). However, the correlation of C1q DSAs with C4d IF is not statistically significant (P = .24). Importantly, C1q+ DSAs were observed in 16 of 17 cases with C4d IF+; 24 cases had circulating C1q+ DSAs without detectable C4d staining, suggesting that that the presence of C1q+ DSAs may precede the detection of C4d deposition in EMB specimens and/or the development of antibody-mediated rejection. CONCLUSIONS: In this cohort of 44 patients, no significant correlation was observed between circulating C1q DSAs and C4d IF in EMB specimens. Additional studies are needed to further evaluate the association of C1q DSAs with EMB specimens and C4d staining.

Prior Sternotomy and Ventricular Assist Device Implantation Do Not Adversely Impact Survival or Allograft Function After Heart Transplantation.

BACKGROUND: Orthotopic heart transplantation (OHT) remains the gold standard for end-stage heart failure. However, donor availability is severely limited. With a median wait time of 6.6 months and more than 12% of patients waiting 5 or more years, the decision is often made to implant a left ventricular assist device (LVAD) as a bridge to transplantation for medical stabilization. Furthermore, the number of patients who have had at least one prior sternotomy while awaiting transplantation is increasing. Previous studies have indicated reoperative sternotomy as a risk factor for compromised survival. Concerns are specifically focused on perioperative, short-term, and long-term outcomes after LVAD explantation or redo sternotomy before OHT because of increasing operative complexity. We hypothesize that despite the greater technical difficulty caused by LVAD explantation or redo sternotomy, outcomes would not be compromised. METHODS: We retrospectively analyzed patients who underwent OHT at the University of Pennsylvania during a 5-year period (2008-2013; n = 253). All patients who underwent a bridge to transplantation LVAD (n = 72) or prior sternotomy (n = 65) were compared with those undergoing OHT with a virgin chest (n = 116). Preoperative, intraoperative, and postoperative variables were analyzed. Short- and long-term survival were studied (minimum follow-up, 6 months). RESULTS: Comorbidities were similar among the groups. There was no difference in donor allograft ischemic time (p = 0.6). However, cardiopulmonary bypass time was longer in both bridge to transplantation and prior sternotomy cohorts (p < 0.00001). The blood transfusion requirement was higher in bridge to transplantation (12.5 ± 13.7 units; p = 0.0007) and prior sternotomy groups (11.7 ± 12.9 units; p = 0.02) as compared with the virgin chest cohort (7.1 ± 10.7 units). For bridge to transplantation, both time to extubation (1.0 ± 1.6 versus 0.9 ± 1.0 days; p = 0.03) and intensive care unit length of stay (7.0 ± 7.0 versus 6.0 ± 7.0 days; p = 0.06) were longer compared with the virgin chest cohort. The same was true for prior sternotomy (extubation time, 1.9 ± 4.4 days; p = 0.005; intensive care unit length of stay, 8.0 ± 12.0 days; p = 0.06). There was no difference in hospital length of stay (p = 0.2). Overall, there was no difference in short- or long-term survival. CONCLUSIONS: Implantation of an LVAD as a bridge to transplantation or prior sternotomy does not adversely impact allograft function, hospital length of stay, or long-term outcomes after OHT. The decision to manage a patient medically while awaiting transplantation versus an LVAD bridge strategy should not be limited by concerns of subsequent poor outcomes after transplantation.

Circulating donor-specific anti-human leukocyte antigen antibodies and complement C4d deposition are associated with the development of cardiac allograft vasculopathy.

BACKGROUND: Cardiac allograft vasculopathy (CAV) continues to be a limiting factor in long-term survival of heart transplant recipients (HTRs). Pathophysiologic and immunologic factors affecting CAV are complex, and criteria for early diagnosis remain elusive. METHODS: We performed a retrospective analysis of the relationship between donor-specific antibody (DSA), C4d immunofluorescence, and the development of CAV. RESULTS: We evaluated 330 endomyocardial biopsy (EMB) specimens from 112 cardiac grafts. Twenty-four (21%) of 112 grafts developed CAV, and 18 (75%) of 24 were positive for C4d. Patients with DSA (n = 51) against human leukocyte antigen class I (n = 5), II (n = 26), or both (n = 20) developed CAV at a rate of 40%, 38%, and 20% and a mean time to CAV of 89, 47, and 25 months, respectively. Of 61 grafts without DSA, only 13% developed CAV, with a mean time to CAV of 116 months. CONCLUSIONS: Compared with the general HTR population, patients with graft dysfunction and DSA or positive C4d on EMB show a statistically significant increased incidence of CAV and allograft failure, suggesting an antibody-mediated injury. The presence of pre- and posttransplant DSA, even in the absence of positive C4d immunofluorescence, may identify a group of HTRs at increased risk of developing CAV.

Diagnosis and treatment of sleep disordered breathing in hospitalized cardiac patients: a reduction in 30-day hospital readmission rates.

BACKGROUND: Sleep disordered breathing (SDB) is associated with significant cardiovascular sequelae and positive airway pressure (PAP) has been shown to improve heart failure and prevent the recurrence of atrial fibrillation in cardiac patients with sleep apnea. Patients who are hospitalized with cardiac conditions frequently have witnessed symptoms of SDB but often do not have a diagnosis of sleep apnea. We implemented a clinical paradigm to perform unattended sleep studies and initiate treatment with PAP in hospitalized cardiac patients with symptoms consistent with SDB. We hypothesized that PAP adherence in cardiac patients with SDB would reduce readmission rates 30 days after discharge. METHODS: 106 consecutive cardiac patients hospitalized for heart failure, arrhythmias, and myocardial infarction and who reported symptoms of SDB were evaluated. Patients underwent a type III portable sleep study and those patients diagnosed with sleep apnea were started on PAP. Demographic data, SDB type, PAP adherence, and data regarding 30-day hospital readmission/ED visits were collected. RESULTS: Of 106 patients, 104 had conclusive diagnostic studies using portable monitoring systems. Seventy-eight percent of patients (81/104) had SDB (AHI ≥ 5 events/h). Eighty percent (65/81) had predominantly obstructive sleep apnea, and 20% (16/81) had predominantly central sleep apnea. None of 19 patients (0%) with adequate PAP adherence, 6 of 20 (30%) with partial PAP use, and 5 of 17 (29%) of patients who did not use PAP were readmitted to the hospital or visited the emergency department (ED) for a cardiac issue within 30 days from discharge (p = 0.025). CONCLUSIONS: Performing diagnostic unattended sleep studies and initiating PAP treatment in hospitalized cardiac patients was feasible and provided important clinical information. Our data indicate that hospital readmission and ED visits 30 days after discharge were significantly lower in patients with cardiac disease and SDB who adhered to PAP treatment than those who were not adherent. COMMENTARY: A commentary on this article appears in this issue on page 1067.

Biomarker predictors of cardiac hospitalization in chronic heart failure: a recurrent event analysis.

BACKGROUND: Identification of heart failure (HF) patients at risk for hospitalization may improve care and reduce costs. We evaluated 9 biomarkers as predictors of cardiac hospitalization in chronic HF. METHODS AND RESULTS: In a multicenter cohort of 1,512 chronic HF outpatients, we assessed the association between 9 biomarkers and cardiac hospitalization with the use of a recurrent events approach. Over a median follow-up of 4 years, 843 participants experienced ≥ 1 hospitalizations (total 2,178 hospitalizations). B-type natriuretic peptide (BNP) and troponin I (TnI) exhibited the strongest associations with risk of hospitalization (hazard ratio [HR] 3.8 [95% confidence interval (CI) 2.9-4.9] and HR 3.3 [95% CI 2.8-3.9]; 3rd vs 1st tertiles). Soluble Fms-like tyrosine kinase receptor 1 (sFlt-1) exhibited the next strongest association (HR 2.8 [95% CI 2.4-3.4]), followed by soluble Toll-like receptor 2 (HR 2.3 [95% CI 2.0-2.8]) and creatinine (HR 1.9 [95% CI 1.6-2.4]). Within ischemic/nonischemic subgroups, BNP and TnI remained most strongly associated. Except for creatinine, HRs for all biomarkers studied were smaller within the ischemic subgroup, suggesting greater importance of cardiorenal interactions in decompensation of ischemic HF. CONCLUSION: Although BNP and TnI exhibited the strongest associations with hospitalization, etiology-dependent associations for the remaining biomarkers suggest etiology-specific mechanisms for HF exacerbation. sFlt-1 exhibited a strong association with cardiac hospitalization, highlighting its potential role as a biomarker of HF morbidity.

Incidence, risk, and consequences of atrial arrhythmias in patients with continuous-flow left ventricular assist devices.

BACKGROUND: Although atrial arrhythmias (AAs) are common in heart failure, the incidence of AAs subsequent to the placement of left ventricular assist devices (LVADs) has not been elucidated. METHODS: Patients receiving a HeartMate II LVAD in the bridge to transplant (n = 490) and destination therapy (n = 634) trials were included (n = 1125). AAs requiring treatment were recorded, regardless of symptoms. Using Cox models with and without a 60-day blanking period, risk factors for early and late AAs were determined. RESULTS: In total, there were 271 AAs in 231 patients (21%), most of which occurred within the first 60 days. Patients with and without AAs had similar survival (p = 0.16). Serum creatinine (hazard ratio [HR] = 1.49 per unit increase, 1.18 to 1.88; p < 0.001) and ejection fraction (HR = 0.98 per 1% increase, 0.95 to 0.999; p = 0.04) were associated with AAs in a multivariable model. Although quality of life (QoL) and functional status improved in all patients, those with AAs had worse unadjusted QoL (p < 0.001) and a decreased rate of improvement in six-minute walk distance over six to 24 months postimplant (p = 0.016). CONCLUSIONS: Approximately one-fifth of LVAD patients have AAs, most commonly within the first 60 days of support. Preoperative creatinine is a strong risk factor for early and late AAs. Although AAs do not impact survival, they are associated with decreased functional status and QoL improvements during LVAD support.

Correlation of circulating donor-specific anti-HLA antibodies and presence of C4d in endomyocardial biopsy with heart allograft outcomes: a single-center, retrospective study.

BACKGROUND: Donor-specific antibodies (DSA) are associated with increased cardiac graft loss and cardiac vasculopathy (CAV). Detection of antibody-mediated rejection (AMR) relies on graft dysfunction, C4d immunofluorescence (IF) and DSA. METHODS: We retrospectively studied the relationship of DSA, endomyocardial biopsy (EMB) and C4d IF to cardiac transplant outcomes. DSA were evaluated against HLA class I and II specificities, both pre- and post-transplant, using microbead-based assays. RESULTS: Of 626 cardiac transplant patients, 109 with concurrent EMBs and C4d IF and DSA measurement were included in this study. In patients with and without DSA, CAV occurred in 31% and 13% and acute cellular rejection (ACR) in 100% and 84%, respectively. One hundred ten of 170 EMBs procured during episodes of graft dysfunction had concurrent DSA. In these patients, C4d IF correlated better with DSA to class I or both class I and II and less so in patients with DSA to class II. Graft failure (GF) rates of 40%, 29% and 58% with average times to GF of 33, 77 and 48 months were seen in patients with DSA to class I, II or both, respectively. CONCLUSIONS: Patients with DSA to class I or to both class I and II showed a correlation with C4d IF and had higher GF rates compared to patients with DSA to only class II or no DSA; patients with DSA to class II remained at risk for CAV. Episodes of ACR and CAV, but not AMR, appeared to be more frequently associated with graft dysfunction in patients with circulating DSA.