Rare Variant Genetics and Dilated Cardiomyopathy Severity: The DCM Precision Medicine Study.

BACKGROUND: Dilated cardiomyopathy (DCM) can lead to advanced disease, defined herein as necessitating a durable left ventricular assist device or a heart transplant (LVAD/HT). DCM is known to have a genetic basis, but the association of rare variant genetics with advanced DCM has not been studied. METHODS: We analyzed clinical and genetic sequence data from patients enrolled between 2016 and 2021 in the US multisite DCM Precision Medicine Study, which was a geographically diverse, multiracial, multiethnic cohort. Clinical evaluation included standardized patient interview and medical record query forms. DCM severity was classified into 3 groups: patients with advanced disease with LVAD/HT; patients with an implantable cardioverter defibrillator (ICD) only; or patients with no ICD or LVAD/HT. Rare variants in 36 DCM genes were classified as pathogenic or likely pathogenic or variants of uncertain significance. Confounding factors we considered included demographic characteristics, lifestyle factors, access to care, DCM duration, and comorbidities. Crude and adjusted associations between DCM severity and rare variant genetic findings were assessed using multinomial models with generalized logit link. RESULTS: Patients' mean (SD) age was 51.9 (13.6) years; 42% were of African ancestry, 56% were of European ancestry, and 44% were female. Of 1198 patients, 347 had LVAD/HT, 511 had an ICD, and 340 had no LVAD/HT or ICD. The percentage of patients with pathogenic or likely pathogenic variants was 26.2%, 15.9%, and 15.0% for those with LVAD/HT, ICD only, or neither, respectively. After controlling for sociodemographic characteristics and comorbidities, patients with DCM with LVAD/HT were more likely than those without LVAD/HT or ICD to have DCM-related pathogenic or likely pathogenic rare variants (odds ratio, 2.3 [95% CI, 1.5-3.6]). The association did not differ by ancestry. Rare variant genetic findings were similar between patients with DCM with an ICD and those without LVAD/HT or ICD. CONCLUSIONS: Advanced DCM was associated with higher odds of rare variants in DCM genes adjudicated as pathogenic or likely pathogenic, compared with individuals with less severe DCM. This finding may help assess the risk of outcomes in management of patients with DCM and their at-risk family members. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03037632.

Effectiveness of the Family Heart Talk Communication Tool in Improving Family Member Screening for Dilated Cardiomyopathy: Results of a Randomized Trial.

BACKGROUND: Managing disease risk among first-degree relatives of probands diagnosed with a heritable disease is central to precision medicine. A critical component is often clinical screening, which is particularly important for conditions like dilated cardiomyopathy (DCM) that remain asymptomatic until severe disease develops. Nonetheless, probands are frequently ill-equipped to disseminate genetic risk information that motivates at-risk relatives to complete recommended clinical screening. An easily implemented remedy for this key issue has been elusive. METHODS: The DCM Precision Medicine Study developed Family Heart Talk, a booklet designed to help probands with DCM communicate genetic risk and the need for cardiovascular screening to their relatives. The effectiveness of the Family Heart Talk booklet in increasing cardiovascular clinical screening uptake among first-degree relatives was assessed in a multicenter, open-label, cluster-randomized, controlled trial. The primary outcome measured in eligible first-degree relatives was completion of screening initiated within 12 months after proband enrollment. Because probands randomized to the intervention received the booklet at the enrollment visit, eligible first-degree relatives were limited to those who were alive the day after proband enrollment and not enrolled on the same day as the proband. RESULTS: Between June 2016 and March 2020, 1241 probands were randomized (1:1) to receive Family Heart Talk (n=621) or not (n=620) within strata defined by site and self-identified race/ethnicity (non-Hispanic Black, non-Hispanic White, or Hispanic). Final analyses included 550 families (n=2230 eligible first-degree relatives) in the Family Heart Talk arm and 561 (n=2416) in the control arm. A higher percentage of eligible first-degree relatives completed screening in the Family Heart Talk arm (19.5% versus 16.0%), and the odds of screening completion among these first-degree relatives were higher in the Family Heart Talk arm after adjustment for proband randomization stratum, sex, and age quartile (odds ratio, 1.30 [1-sided 95% CI, 1.08-∞]). A prespecified subgroup analysis did not find evidence of heterogeneity in the adjusted intervention odds ratio across race/ethnicity strata (P=0.90). CONCLUSIONS: Family Heart Talk, a booklet that can be provided to patients with DCM by clinicians with minimal additional time investment, was effective in increasing cardiovascular clinical screening among first-degree relatives of these patients. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03037632.

Financial impact of donation after circulatory death heart transplantation: A single-center analysis.

INTRODUCTION: Clinical success of donation after circulatory death (DCD) heart transplantation is leading to growing adoption of this technique. In comparison to procurement from a brain-dead donor, DCD requires additional resources. The economic impact of DCD heart transplantation from the hospital perspective is not well known. METHODS: We compared the financial data of patients who received DCD allografts to those who received a DBD organ at our institution from January 1, 2021 to December 31, 2022. We also compared the cost of ex-situ machine perfusion to in-situ organ perfusion employed during DCD recovery. RESULTS: We performed 58 DBD and 22 DCD heart-alone transplantations during the study period. Out of 22 DCD grafts, 16 were recovered with thoracoabdominal normothermic regional perfusion (TA-NRP) and six with direct procurement followed by normothermic machine perfusion (DP-NMP). The contribution margin per case for DBD versus DCD was $234,362 and $235,440 (P = .72). The direct costs did not significantly differ between the two groups ($171,949 and 186,250; P = .49). In comparing the two methods of procuring hearts from DCD donors, the direct cost of TA-NRP was $155,955 in comparison to $223,399 for DP-NMP (P = .21). This difference translated into a clinically meaningful but not statistically significant greater contribution margin for TA-NRP ($242, 657 vs. $175,768; P = .34). CONCLUSIONS: Our data showed that the adoption of DCD procurement did not have a negative financial impact on the contribution margin in our institution. Programs considering starting DCD heart transplantation, and those who are currently performing DCD procurement should evaluate their own financial situation.

Preoperative Amiodarone and Primary Graft Dysfunction in Heart Transplantation.

BACKGROUND: Preoperative amiodarone effects on postorthotopic heart transplant (OHT) outcomes remain controversial. OBJECTIVE: The purpose of this study was to determine the effect of cumulative pre-OHT amiodarone exposure on severe primary graft dysfunction (PGD). METHODS: We retrospectively reviewed adult OHT recipients between August 2012 and June 2018. Primary outcome was severe PGD in patients receiving amiodarone at 3, 6, and 12 months prior to OHT compared with those not receiving amiodarone. Secondary outcomes included intensive care unit (ICU) and hospital length of stay, duration of mechanical ventilation, early graft failure (EGF), mortality at 3, 6, and 12 months post-OHT, and 30-day incidence of postoperative tachyarrhythmias, bradycardia, permanent pacemaker implantation, and rejection. RESULTS: Incidence of severe PGD was 12.5% in those who received amiodarone compared to 6.8% in those who did not (14 vs 6, P = 0.18). Cumulative preoperative amiodarone significantly increased the odds of severe PGD at 3 months (odds ratio [OR]: 1.03; 95% confidence interval [CI]: 1.001-1.06; P = 0.044) and 6 months (OR: 1.02, 95% CI: 1.003-1.044; P = 0.024) in a multivariate logistic regression. Patients on amiodarone had significantly higher rates of postoperative bradycardia (13.4% vs 4.5%, P = 0.03). CONCLUSION AND RELEVANCE: A trend toward increased PGD was present in patients receiving preoperative amiodarone. This finding combined with the regression showing significantly increased odds of PGD with increasing 3 and 6 month cumulative amiodarone dose is clinically concerning. Escalation of care with pacemaker implantation was required more frequently in patients on pre-OHT amiodarone.

Impact of donation after circulatory death heart transplantation on waitlist outcomes and transplantation activity.

INTRODUCTION: Donation after circulatory death (DCD) heart transplantation has been shown to have comparable outcomes to transplantation using brain death donors (DBDs). This study evaluates the impact of this alternative source of allografts on waitlist mortality and transplant volume. METHODS: We compared waitlist mortality and transplant rates in patients who were registered before (2019 period) and after we adopted DCD heart transplantation (2021 period). RESULTS: We identified 111 patients who were on the waiting list in 2019 and 77 patients who were registered during 2021. Total number of donor organ offers received in 2019 was 385 (178 unique donors) versus 3450 (1145 unique donors) in 2021. More than 40% of all donors in 2021 were DCDs. Waitlist mortality was comparable for patients in 2019 and 2021 (18/100 person-years in 2019 vs. 26/100 person-years in 2021, p = .49). The transplant rate was 67/100 person-years in 2019 versus 207/100 person-years in 2021 (p < .001). After adjusting for acuity status, gender, blood type, and weight, patients listed in 2021 had 2.08 times greater chance of transplantation compared to patients listed in 2019 (HR 2.08, 95% confidence interval [CI] 1.26-3.45, p = .004). CONCLUSIONS: Use of DCD donor hearts significantly increased heart transplant rate in our institution.

Genetic Architecture of Dilated Cardiomyopathy in Individuals of African and European Ancestry.

Importance: Black patients with dilated cardiomyopathy (DCM) have increased familial risk and worse outcomes than White patients, but most DCM genetic data are from White patients. Objective: To compare the rare variant genetic architecture of DCM by genomic ancestry within a diverse population of patients with DCM. Design: Cross-sectional study enrolling patients with DCM who self-identified as non-Hispanic Black, Hispanic, or non-Hispanic White from June 7, 2016, to March 15, 2020, at 25 US advanced heart failure programs. Variants in 36 DCM genes were adjudicated as pathogenic, likely pathogenic, or of uncertain significance. Exposure: Presence of DCM. Main Outcomes and Measures: Variants in DCM genes classified as pathogenic/likely pathogenic/uncertain significance and clinically actionable (pathogenic/likely pathogenic). Results: A total of 505, 667, and 26 patients with DCM of predominantly African, European, or Native American genomic ancestry, respectively, were included. Compared with patients of European ancestry, a lower percentage of patients of African ancestry had clinically actionable variants (8.2% [95% CI, 5.2%-11.1%] vs 25.5% [95% CI, 21.3%-29.6%]), reflecting the lower odds of a clinically actionable variant for those with any pathogenic variant/likely pathogenic variant/variant of uncertain significance (odds ratio, 0.25 [95% CI, 0.17-0.37]). On average, patients of African ancestry had fewer clinically actionable variants in TTN (difference, -0.09 [95% CI, -0.14 to -0.05]) and other genes with predicted loss of function as a disease-causing mechanism (difference, -0.06 [95% CI, -0.11 to -0.02]). However, the number of pathogenic variants/likely pathogenic variants/variants of uncertain significance was more comparable between ancestry groups (difference, -0.07 [95% CI, -0.22 to 0.09]) due to a larger number of non-TTN non-predicted loss of function variants of uncertain significance, mostly missense, in patients of African ancestry (difference, 0.15 [95% CI, 0.00-0.30]). Published clinical case-based evidence supporting pathogenicity was less available for variants found only in patients of African ancestry (P < .001). Conclusion and Relevance: Patients of African ancestry with DCM were less likely to have clinically actionable variants in DCM genes than those of European ancestry due to differences in genetic architecture and a lack of representation of African ancestry in clinical data sets.

A Fully Magnetically Levitated Left Ventricular Assist Device - Final Report.

BACKGROUND: In two interim analyses of this trial, patients with advanced heart failure who were treated with a fully magnetically levitated centrifugal-flow left ventricular assist device were less likely to have pump thrombosis or nondisabling stroke than were patients treated with a mechanical-bearing axial-flow left ventricular assist device. METHODS: We randomly assigned patients with advanced heart failure to receive either the centrifugal-flow pump or the axial-flow pump irrespective of the intended goal of use (bridge to transplantation or destination therapy). The composite primary end point was survival at 2 years free of disabling stroke or reoperation to replace or remove a malfunctioning device. The principal secondary end point was pump replacement at 2 years. RESULTS: This final analysis included 1028 enrolled patients: 516 in the centrifugal-flow pump group and 512 in the axial-flow pump group. In the analysis of the primary end point, 397 patients (76.9%) in the centrifugal-flow pump group, as compared with 332 (64.8%) in the axial-flow pump group, remained alive and free of disabling stroke or reoperation to replace or remove a malfunctioning device at 2 years (relative risk, 0.84; 95% confidence interval [CI], 0.78 to 0.91; P<0.001 for superiority). Pump replacement was less common in the centrifugal-flow pump group than in the axial-flow pump group (12 patients [2.3%] vs. 57 patients [11.3%]; relative risk, 0.21; 95% CI, 0.11 to 0.38; P<0.001). The numbers of events per patient-year for stroke of any severity, major bleeding, and gastrointestinal hemorrhage were lower in the centrifugal-flow pump group than in the axial-flow pump group. CONCLUSIONS: Among patients with advanced heart failure, a fully magnetically levitated centrifugal-flow left ventricular assist device was associated with less frequent need for pump replacement than an axial-flow device and was superior with respect to survival free of disabling stroke or reoperation to replace or remove a malfunctioning device. (Funded by Abbott; MOMENTUM 3 ClinicalTrials.gov number, NCT02224755.).

Prevalence and Cumulative Risk of Familial Idiopathic Dilated Cardiomyopathy.

Importance: Idiopathic dilated cardiomyopathy (DCM) aggregates in families, and early detection in at-risk family members can provide opportunity to initiate treatment prior to late-phase disease. Most studies have included only White patients, yet Black patients with DCM have higher risk of heart failure-related hospitalization and death. Objective: To estimate the prevalence of familial DCM among DCM probands and the age-specific cumulative risk of DCM in first-degree relatives across race and ethnicity groups. Design, Setting, and Participants: A family-based, cross-sectional study conducted by a multisite consortium of 25 US heart failure programs. Participants included patients with DCM (probands), defined as left ventricular systolic dysfunction and left ventricular enlargement after excluding usual clinical causes, and their first-degree relatives. Enrollment commenced June 7, 2016; proband and family member enrollment concluded March 15, 2020, and April 1, 2021, respectively. Exposures: The presence of DCM in a proband. Main Outcomes and Measures: Familial DCM defined by DCM in at least 1 first-degree relative; expanded familial DCM defined by the presence of DCM or either left ventricular enlargement or left ventricular systolic dysfunction without known cause in at least 1 first-degree relative. Results: The study enrolled 1220 probands (median age, 52.8 years [IQR, 42.4-61.8]; 43.8% female; 43.1% Black and 8.3% Hispanic) and screened 1693 first-degree relatives for DCM. A median of 28% (IQR, 0%-60%) of living first-degree relatives were screened per family. The crude prevalence of familial DCM among probands was 11.6% overall. The model-based estimate of the prevalence of familial DCM among probands at a typical US advanced heart failure program if all living first-degree relatives were screened was 29.7% (95% CI, 23.5% to 36.0%) overall. The estimated prevalence of familial DCM was higher in Black probands than in White probands (difference, 11.3% [95% CI, 1.9% to 20.8%]) but did not differ significantly between Hispanic probands and non-Hispanic probands (difference, -1.4% [95% CI, -15.9% to 13.1%]). The estimated prevalence of expanded familial DCM was 56.9% (95% CI, 50.8% to 63.0%) overall. Based on age-specific disease status at enrollment, estimated cumulative risks in first-degree relatives at a typical US advanced heart failure program reached 19% (95% CI, 13% to 24%) by age 80 years for DCM and 33% (95% CI, 27% to 40%) for expanded DCM inclusive of partial phenotypes. The DCM hazard was higher in first-degree relatives of non-Hispanic Black probands than non-Hispanic White probands (hazard ratio, 1.89 [95% CI, 1.26 to 2.83]). Conclusions and Relevance: In a US cross-sectional study, there was substantial estimated prevalence of familial DCM among probands and modeled cumulative risk of DCM among their first-degree relatives. Trial Registration: ClinicalTrials.gov Identifier: NCT03037632.

Prospective Multicenter Study of Myocardial Recovery Using Left Ventricular Assist Devices (RESTAGE-HF [Remission from Stage D Heart Failure]): Medium-Term and Primary End Point Results.

BACKGROUND: Left ventricular assist device (LVAD) unloading and hemodynamic support in patients with advanced chronic heart failure can result in significant improvement in cardiac function allowing LVAD removal; however, the rate of this is generally considered to be low. This prospective multicenter nonrandomized study (RESTAGE-HF [Remission from Stage D Heart Failure]) investigated whether a protocol of optimized LVAD mechanical unloading, combined with standardized specific pharmacological therapy to induce reverse remodeling and regular testing of underlying myocardial function, could produce a higher incidence of LVAD explantation. METHODS: Forty patients with chronic advanced heart failure from nonischemic cardiomyopathy receiving the Heartmate II LVAD were enrolled from 6 centers. LVAD speed was optimized with an aggressive pharmacological regimen, and regular echocardiograms were performed at reduced LVAD speed (6000 rpm, no net flow) to test underlying myocardial function. The primary end point was the proportion of patients with sufficient improvement of myocardial function to reach criteria for explantation within 18 months with sustained remission from heart failure (freedom from transplant/ventricular assist device/death) at 12 months. RESULTS: Before LVAD, age was 35.1±10.8 years, 67.5% were men, heart failure mean duration was 20.8±20.6 months, 95% required inotropic and 20% temporary mechanical support, left ventricular ejection fraction was 14.5±5.3%, end-diastolic diameter was 7.33±0.89 cm, end-systolic diameter was 6.74±0.88 cm, pulmonary artery saturations were 46.7±9.2%, and pulmonary capillary wedge pressure was 26.2±7.6 mm Hg. Four enrolled patients did not undergo the protocol because of medical complications unrelated to the study procedures. Overall, 40% of all enrolled (16/40) patients achieved the primary end point, P<0.0001, with 50% (18/36) of patients receiving the protocol being explanted within 18 months (pre-explant left ventricular ejection fraction, 57±8%; end-diastolic diameter, 4.81±0.58 cm; end-systolic diameter, 3.53±0.51 cm; pulmonary capillary wedge pressure, 8.1±3.1 mm Hg; pulmonary artery saturations 63.6±6.8% at 6000 rpm). Overall, 19 patients were explanted (19/36, 52.3% of those receiving the protocol). The 15 ongoing explanted patients are now 2.26±0.97 years after explant. After explantation survival free from LVAD or transplantation was 90% at 1-year and 77% at 2 and 3 years. CONCLUSIONS: In this multicenter prospective study, this strategy of LVAD support combined with a standardized pharmacological and cardiac function monitoring protocol resulted in a high rate of LVAD explantation and was feasible and reproducible with explants occurring in all 6 participating sites. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01774656.

PROVIDE-HF primary results: Patient-Reported Outcomes inVestigation following Initiation of Drug therapy with Entresto (sacubitril/valsartan) in heart failure.

BACKGROUND: In PARADIGM-HF, sacubitril/valsartan improved quality of life (QOL) versus enalapril in heart failure with reduced ejection fraction (HFrEF), yet limited data are available regarding QOL changes after sacubitril/valsartan initiation in routine practice. METHODS: PROVIDE-HF was a prospective study within a national research network (Patient-Centered Outcomes Research Network) of HFrEF outpatients recently initiated on sacubitril/valsartan versus controls with recent angiotensin-converting enzyme inhibitor/angiotensin receptor blocker initiation/dose change. The primary end point was mean Kansas City Cardiomyopathy Questionnaire (KCCQ) change through 12 weeks. Other end points included responder analyses: ≥5-point and ≥20-point KCCQ increase. Adjusted QOL change was estimated after propensity score weighting. RESULTS: Overall, 270 patients had both baseline and 12-week KCCQ data (151 sacubitril/valsartan; 119 control). The groups had similar demographics and HF details: median EF 28% and N-terminal pro-brain natriuretic peptide 1083 pg/mL. Sacubitril/valsartan patients had larger improvements in KCCQ (mean difference +4.76; P = .027) and were more likely to have a ≥5-point and ≥20-point response (all P < .05). Adjusted comparisons demonstrated similar numerical improvements in the change in KCCQ (+4.55; 95% CI -0.89 to 9.99; P = .101) and likelihood of ≥5-point increase (odds ratio 1.55; 95% CI: 0.84-2.86; P = .16); ≥20-point increase remained statistically significant (odds ratio 3.79; 95% CI 1.47-9.73; P = .006). CONCLUSIONS: In this prospective HFrEF study of sacubitril/valsartan initiation compared with recent angiotensin-converting enzyme inhibitor/angiotensin receptor blocker initiation/dose change, the between-group difference in the primary end point, mean KCCQ change at 12 weeks was not statistically significant following adjustment, but sacubitril/valsartan initiation was associated with early improvements in QOL and a higher likelihood of ≥20-point improvement in KCCQ at 12 weeks. These data add additional real-world evidence related to patient-reported outcomes following the initiation of sacubitril/valsartan in routine clinical practice.

Impact of temporary mechanical circulatory support for early graft failure on post-heart transplantation outcomes.

Although temporary mechanical circulatory support (tMCS) for hemodynamic failure following heart transplantation is associated with increased early morbidity and mortality, the impact of etiology of graft dysfunction and long-term clinical implications are less well known. The objective of our study was to evaluate outcomes in patients who required venoarterial extracorporeal membrane oxygenation (VA ECMO) or temporary right ventricular assist device (RVAD) support for either primary or secondary early graft dysfunction. Hospital mortality in 27 patients who required tMCS following heart transplantation at our institution between 2007 and 2017 was 56%, 30% in patients with right ventricular dysfunction secondary to increased afterload, 60% in patients with primary graft dysfunction, and 100% in patients with graft failure secondary to coagulopathy with intraoperative bleeding or overwhelming sepsis. Conditional 1-year and 5-year survival was comparable between patients with, and without, the need for post-transplantation support with tMCS (98% and 89%; 92% and 65% at 1 and 5 years, P = .21). Etiology of early graft failure plays an important part in determining the short-term post-heart transplantation outcome. Although complications associated with tMCS use, such as renal dysfunction and infection, extend beyond index transplant hospitalization, long-term conditional survival is not compromised.

Electronic cigarette extract induced toxic effect in iPS-derived cardiomyocytes.

BACKGROUND: Cigarette smoking is an important risk factor for cardiac diseases. In the current study, we sought to assess the effect of electronic cigarette extract (ECE) and conventional cigarette smoke extract (CSE) on cardiomyocytes. METHODS: iPSCs-derived cardiomyocytes were used in the study to evaluate cellular toxicities. Cells were exposed to either ECE or CSE for two consecutive days as an acute exposure or every other day for 14 days. Concentration of nicotine in both ECE and CSE were measured by Mass-Spectrometry and Q-Exactive-HF was used to identify other ingredients in both extracts. Fluorescent microscopy was used to measure the oxidative stress after ECE and CSE exposure. Motility and beat frequency of cardiomyocytes were determined using the Sisson-Ammons Video Analysis system. Heart failure target panel genes of exposed cardiomyocytes were compared to control unexposed cells. RESULTS: Despite nicotine concentration in CSE being six-fold higher than ECE (50 µg in CSE and 8 µg in ECE), ECE had similar toxic effect on cardiomyocytes. Both CSE and ECE generate significant cellular reactive oxygen species. The Sisson-Ammons Video Analysis (SAVA) analysis showed significant changes in myocyte function with both CSE and ECE slowing beating and increasing cell death. Chronic exposure of both ECE and CSE significantly decreased cardiomyocytes viability long term at all doses. Target panel gene expression profiles of both ECE and CSE exposed cardiomyocytes were different from controls with distinct pattern of genes that involved cell proliferation, inflammation, and apoptosis. CONCLUSION: ECE and CSE produce similar cardiomyocyte toxicities which include generating oxidative stress, negative chronotropic effects, adverse changes in myocardial gene expression and ultimately cell death.

Elevated Heart Rate Following Heart Transplantation Is Associated With Increased Graft Vasculopathy and Mortality.

BACKGROUND: The effect of elevated heart rate (HR) on outcomes after heart transplantation (HT) has not been well established. The aim of this study was to assess predictors of elevated HR following HT and its impact on outcomes. METHODS AND RESULTS: We retrospectively evaluated 394 patients who underwent HT at 2 academic medical centers from 2005 to 2016. Patients were divided into 2 groups based on HR 1 year after HT: HR ≥95 beats/min (n = 162; 41%) and HR <95 beats/min (n = 232; 59%). Median follow-up time was 6.6 (interquartile range [IQR] 2.2-7.5) years. HR ≥95 beats/min 1 year after HT was associated with younger donor age, whereas HR <95 beats/min was associated with heavy donor alcohol use and African-American recipient race. Left ventricular (LV) end-diastolic dimension, mass, and ejection fraction were lower and E/E' higher in the HR ≥95 group at the time of the last follow up. HR ≥95 beats/min at 1 year after HT was independently associated with the development of cardiac allograft vasculopathy and increased mortality. CONCLUSIONS: HR ≥95 beats/min 1 year after HT is associated with a reduction in LV size and function, increased incidence of cardiac allograft vasculopathy, and reduced survival. Studies investigating the effect of medical HR reduction on post-HT outcomes are warranted.

The effect of donor alcohol abuse on outcomes following heart transplantation.

BACKGROUND: Current guidelines recommend against the use of hearts from donors that abuse alcohol. We explored the effect of donor alcohol abuse (AA) on cardiac allograft function and outcomes in heart transplant (HTx) recipients. METHODS: Overall, 370 HTx recipients were divided into two groups: (a) the alcoholic donor group (AD, n = 58) and (b) the non-alcoholic donor group (NAD, n = 312). RESULTS: Recipients in the AD group had a slower heart rate (86 ± 13 vs 93 ± 13, P = 0.004) and an increased incidence of early atrial fibrillation (AF) (30% vs 11%, P = 0.003). Echocardiographic left ventricular mass was higher among alcoholic donors (171.7 ± 66.7 vs 151.6 ± 54.7, P = 0.02). This difference remained present 1 year following HTx (185 ± 43 vs 166 ± 42, P = 0.007). E/E' was higher in the AD group (9.5 ± 3.9 vs 8.4 ± 2.9, P = 0.04) and a larger number of AD recipients had a ventilatory equivalent for VCO2  > 34 (50% vs 31%, P = 0.04) on cardiopulmonary exercise test. There was no significant difference in rejection, cardiac allograft vasculopathy (CAV), or survival between the groups. CONCLUSIONS: Our data suggest that donor AA does not impact rejection, CAV, or intermediate-term survival, but may cause increased incidence of post-HTx AF and impaired cardiac allograft diastolic function.

Sirolimus for Recurrent Giant Cell Myocarditis After Heart Transplantation: A Unique Therapeutic Strategy.

CLINICAL FEATURES: Giant cell myocarditis (GCM) is a rare and a rapidly progressive disorder with fatal outcomes such that patients often require heart transplantation. We present a case of recurrent GCM in a transplanted patient with a history of Crohn disease requiring a novel therapeutic approach. THERAPEUTIC CHALLENGE: After the orthotopic heart transplantation, GCM recurred on aggressive immunosuppression over the months, which included corticosteroids, basiliximab, tacrolimus, antithymocyte globulin, and rituximab. Although combination immunosuppressive therapy containing cyclosporine and 2-4 additional drugs including corticosteroids, azathioprine, mycophenolate mofetil, muromonab, gammaglobulin, or methotrexate have shown to prolong the transplant-free survival by keeping the disease under control, its role in preventing and treating recurrence posttransplantation is unclear. SOLUTION: We added sirolimus, a macrolide antibiotic, with properties of T- and B-lymphocyte proliferation inhibition on the above immunosuppressive treatment postrecurrence of GCM. After sirolimus initiation and continuation, the patient has remained disease free.

Can we expect improvements in outcomes with centrifugal vs axial flow left ventricular assist devices in patients transitioned from extracorporeal life support?

BACKGROUND: Several patient-related characteristics have been associated with inferior outcomes following durable left ventricular assist device (LVAD) implantation in patients transitioned from venoarterial extracorporeal membrane oxygenation (VA ECMO). The impact of LVAD pump type used is less well-known. METHODS: We compared outcomes between patents who received axial and centrifugal flow LVADs following stabilization with VA ECMO. RESULTS: From January 2011 to December 2018, we implanted 28 LVADs in patients transitioned from VA ECMO. This included 17 axial flow devices (HeartMate II LVAD, Abbott Laboratories, Chicago, IL) and 11 centrifugal flow pumps (eight HeartWare HVADs; Medtronic, Minneapolis, MN and three HeartMate 3 LVAS pumps; Abbott Laboratories, Chicago, IL). There was no difference in hospital mortality (23.5% vs 18.2%, P = .74) or 1-year survival (P = .31) between the devices. There were no differences in adverse event rates between the two pump types, apart from a higher rate of gastrointestinal bleeding in patients who received centrifugal flow pumps (1.44 events per 100 patient-months vs 14.67 events per 100 patient-months, P = .010). Preimplantation levels of alanine aminotransferase (hazard ratio [HR], 1.001; 95% confidence interval [CI], 1.000 to 1.002; P = .004) and elevated serum creatinine level (HR, 3.480; 95% CI, 1.121-10.807; P = .031) emerged as significant predictors of decreased 1-year survival. CONCLUSIONS: Preimplantation optimization of end-organ function is the single most important determinant of successful post-LVAD survival in patients transitioned from extracorporeal life support. There is no association of pump type with LVAD outcomes up to 1-year post implantation.

Left Ventricular Assist Devices in Pulmonary Hypertension Group 2 With Significantly Elevated Pulmonary Vascular Resistance: A Bridge to Cure.

BACKGROUND: Pulmonary hypertension secondary to left heart disease (WHO Group 2) is a known risk factor in patients with heart failure. The favourable effect of left ventricular assist devices (LVAD) on pulmonary hypertension has been demonstrated before, although this effect has not been well-studied in advanced pulmonary arterial bed disease with a significant elevation in pulmonary vascular resistance. METHODS: We reviewed the records of 258 LVAD patients in our institution. Patients with elevated mean pulmonary artery pressure (mPAP>25mmHg) and elevated pulmonary vascular resistance (PVR ≥3 Wood units) were included in the study. Patients were divided into two groups based on their baseline PVR (PVR=3-5 Wood units (WU) vs. PVR>5WU). The groups were studied for the changes in their pulmonary haemodynamics after the placement of LVAD. RESULTS: Fifty-one (51) patients were included in the study. All patients showed a significant improvement in their pulmonary haemodynamic parameters post LVAD placement. In the group with the higher PVR, mPAP dropped from a baseline of 43±7mmHg to 22±6mmHg post LVAD placement (p<0.001), while PVR dropped from 6.3±1.2 Wood units to 2.2±1.1 Wood units (p<0.001). In a subgroup of patients who underwent cardiac transplantation post LVAD (n=14), all patients maintained a normalised PVR (<3WU) one year post cardiac transplantation. CONCLUSIONS: Left ventricular assist devices can reverse pulmonary hypertension WHO Group 2 with significantly elevated PVR; this effect is not dependent on the baseline PVR, and is maintained up to one year post cardiac transplantation.

Sinus tachycardia is associated with impaired exercise tolerance following heart transplantation.

BACKGROUND: Sinus tachycardia often presents in heart transplantation (HTx) recipients, but data on its effect on exercise performance are limited. METHODS: Based on mean heart rate (HR) value 3 months after HTx, 181 patients transplanted from 2006 to 2015 at University of Nebraska Medical Center were divided into two groups: (i) HR<95 beats/min (bpm, n=93); and (ii) HR≥95 bpm (n=88). Cardiopulmonary exercise testing (CPET) was performed 1 year after HTx. RESULTS: Mean HR at 3 months post-HTx was 94±11 bpm and did not change significantly at 1 year post-HTx (96±11 bpm, P=.13). HR≥95 bpm at 3 months was associated with younger donor age (OR 1.1; CI 1.0-1.1, P=.02), female donors (OR -2.4; CI 1.16-5.24 P=.02), and lack of donors' heavy alcohol use (OR -0.43; CI 0.17-0.61; P=.04). HR≥95 bpm at 3 months post-HTx was independently associated with decreased exercise capacity in metabolic equivalent (P=.008), reduced peak VO2 (P=.006), and percent of predicted peak VO2 (P=.002) during CPET. CONCLUSIONS: HR≥95 at 3 months following HTx is associated with reduced exercise tolerance in stable HTx recipients. Medical HR reduction after HTx could improve exercise performance after HTx and merits further investigation.

Effect of diltiazem on exercise capacity after heart transplantation.

BACKGROUND: Sinus tachycardia (ST) is common after heart transplantation (HTx). The aim of the study was to evaluate the effect of diltiazem treatment during the first year after HTx on heart rate (HR), cardiac allograft function, and exercise capacity. METHODS: From the total cohort, 25 HTx recipients started diltiazem treatment 4±2 weeks after HTx and continued it for at least 1 year (diltiazem group). Each study case was matched to a control. All patients underwent hemodynamic assessment and cardiopulmonary exercise test (CPET) at 1 year after HTx. RESULTS: HR decreased in the diltiazem group from 99±11 bpm to 94±7 bpm (P=.03) and did not change in the controls (98±11 bpm vs 100±13 bpm, P=.14). The difference between the groups at 1 year after HTx was significant (P=.04). In the diltiazem group left ventricular (LV), stroke volume and ejection fraction increased (48±16 vs 55±17 mL, P=.02, and 60%±10% vs 62%±12% P=.03, respectively) but did not differ from controls. E/E' decreased (10.7±2.7 vs 7.3±1.9, P=.003) while cardiac index was higher (3.5±0.8 vs 3.1±0.5; P=.05) in the diltiazem group at 1-year follow-up. The absolute peak VO2 (21±4 vs 18±6 mL/kg/min; P=.05) and normalized peak VO2 (73%±17% vs 58%±14%; P=.004) were significantly higher in the diltiazem group. CONCLUSIONS: This study showed that diltiazem treatment reduces ST, may improve cardiac allograft function and exercise tolerance during the first year after HTx.

Targeted myocardial gene expression in failing hearts by RNA sequencing.

BACKGROUND: Myocardial recovery with left ventricular assist device (LVAD) therapy is highly variable and difficult to predict. Next generation ribonucleic acid (RNA) sequencing is an innovative, rapid, and quantitative approach to gene expression profiling in small amounts of tissue. Our primary goal was to identify baseline transcriptional profiles in non-ischemic cardiomyopathies that predict myocardial recovery in response to LVAD therapy. We also sought to verify transcriptional differences between failing and non-failing human hearts. METHODS: RNA was isolated from failing (n = 16) and non-failing (n = 8) human hearts. RNA from each patient was reverse transcribed and quantitatively sequenced on the personal genome machine (PGM) sequencer (Ion torrent) for 95 heart failure candidate genes. Coverage analysis as well as mapping the reads and alignment was done using the Ion Torrent Browser Suite™. Differential expression analyses were conducted by empirical analysis of digital gene expression data in R (edgeR) to identify differential expressed genes between failing and non-failing groups, and between responder and non-responder groups respectively. Targeted cardiac gene messenger RNA (mRNA) expression was analyzed in proportion to the total number of reads. Gene expression profiles from the PGM sequencer were validated by performing RNA sequencing (RNAseq) with the Illumina Hiseq2500 sequencing system. RESULTS: The failing sample population was 75% male with an average age of 50 and a left ventricular ejection fraction (LVEF) of 16%. Myosin light chain kinase (MYLK) and interleukin (IL)-6 genes expression were significantly higher in LVAD responders compared to non-responders. Thirty-six cardiac genes were expressed differentially between failing and non-failing hearts (23 decreased, 13 elevated). MYLK, Beta-1 adrenergic receptor (ADRB1) and myosin heavy chain (MYH)-6 expression were among those significantly decreased in failing hearts compared to non-failing hearts. Natriuretic peptide B (NPPB) and IL-6 were significantly elevated. Targeted gene expression profiles obtained from the Ion torrent PGM sequencer were consistent with those obtained from Illumina HiSeq2500 sequencing system. CONCLUSIONS: Heart failure is associated with a network of transcriptional changes involving contractile proteins, metabolism, adrenergic receptors, protein phosphorylation, and signaling factors. Myocardial MYLK and IL-6 expression are positively correlated with ejection fraction (EF) response to LVAD placement. Targeted RNA sequencing of myocardial gene expression can be utilized to predict responders to LVAD therapy and to better characterize transcriptional changes in human heart failure.