Faculty Bibliography

BACKGROUND:Recent innovations in temperature-controlled cardiac transportation allow for static hypothermic preservation of transplant organs during transportation. We assessed differences in donor-derived cell-free DNA (dd-cfDNA) using the SherpaPak cardiac transport system (SCTS) and traditional ice transportation. METHODS:Single-organ heart transplant recipients between January 2020 and January 2022 were included if they had dd-cfDNA measures ≤6 weeks post-transplant along with the baseline biopsy at 6 weeks as part of the surveillance protocol and no biopsy-confirmed rejection ≤90 days. Elevated dd-cfDNA ≥.20% were compared between groups using logistic regression including a subject effect. RESULTS:Of 65 hearts transplanted, 30 were transported with SCTS and 35 on ice. Recipient characteristics were similar between groups. Donors in the SCTS group were older (34 vs. 40 years, p = .04) with a longer total ischemic time (171 vs. 212 min, p = .002). Recipients in the SCTS group had a greater risk of elevated dd-cfDNA unadjusted and adjusted for donor age, and prolonged ischemic times > 3.5 h (Unadjusted odds ratio: 4.9, 95%-CI: 1.08-22.5, p = .039 and Adjusted odds ratio: 5.5, 95%-CI: 1.03-29.6, p = .046). Primary graft dysfunction rates and 1-year mortality were comparable between groups. CONCLUSION/CONCLUSIONS:Elevated dd-cfDNA in patients procured with SCTS may indicate that graft injury was not negated relative to ice transport. However, there were no clinical differences noted in short or long-term outcomes including mortality despite a longer ischemic time in the SCTS group.

BACKGROUND:Right ventricular failure is associated with increased morbidity and mortality. The ProtekDuo (Livanova, Uk) is a dual-lumen cannula that allows for percutaneous right ventricular support and may be connected to a centrifugal blood pump such as the TandemHeart or LifeSparc (Livanova, UK). This systematic review aims to evaluate the safety and efficacy of ProtekDuo right ventricular support and evaluate potential clinical variables that can influence outcomes. METHODS:PubMed, MEDLINE, SCOPUS, EMBASE, and the Cochrane Library were systematically searched. Studies meeting inclusion criteria, where ProtekDuo was used as the right ventricular assist device with reported numerical death counts for mortality as outcome measures. The primary endpoints were in-hospital 30-day and 1-year mortality rates. Secondary endpoints included ICU length of stay, conversion rates to surgical RVADs, ProtekDuo wean rates, duration of use of ProtekDuo, and adverse event rates. RESULTS:Of 49 studies reviewed, 7 met inclusion criteria with study periods between October 2014 and November 2019. ProtekDuo was utilized due to RV failure post-LVAD insertion in 64.8% (68/105) of patients. In-hospital mortality, 30-day mortality, and 1-year mortality ranged between 9%-46%, 15%-40%, and 19%-40%, respectively. Weaning from ProtekDuo and conversion to surgical RVAD ranged between 24%-91% and 11%-35%, respectively. The ICU stay average ranged from 15.8 to 36 days and ProtekDuo mean support duration ranged from 10.5 to 58 days. CONCLUSION/CONCLUSIONS:The ProtekDuo cannula is increasingly utilized as a right ventricular support device. Despite the sparse retrospective data available with variable patient characteristics and study design, percutaneous RV mechanical support via ProtekDuo cannula is a safe and feasible option.

Untreated sleep disorders form a risk of coronary artery disease, hypertension, obesity, and diabetes mellitus. Access to polysomnography is limited, especially during the COVID-19 pandemic, with home sleep apnea testing (HSAT) being a potentially viable alternative. We describe an HSAT protocol in patients with advanced heart failure (HF). In a single-center, observational analysis between 2019 and 2021 in patients with advanced HF and heart transplant (HT), 135 screened positive on the STOP-Bang sleep survey and underwent a validated HSAT (WatchPAT, ZOLL-Itamar). HSAT was successful in 123 patients (97.6%), of whom 112 (91.1%; 84 HF and 28 HT) tested positive for sleep apnea. A total of 91% of sleep apnea cases were obstructive, and 63% were moderate to severe. Multivariable linear regression showed that the apnea hypopnea index was 34% lower in the HT group than in the HF group (p = 0.046) after adjusting for gender, and that this effect persisted in White patients but not among African-Americans. Patient characteristics were similar between groups, with coronary artery disease, diabetes mellitus, and hypertension as the most prevalent co-morbidities. In conclusion, sleep apnea remains prevalent in patients with HF with a high co-morbidity burden. HSAT is a feasible and effective tool for screening and diagnosis in this population.

Right heart failure (RHF) is a complex clinical syndrome that confers high risk of morbidity and mortality. We sought to study RHF using large national database. The study is a retrospective analysis of the National Readmission Database (NRD) of years 2017-2019. Admissions with a primary diagnosis of RHF were included. Study outcomes were temporal trends of RHF diagnosis and predictors of in-hospital mortality and 30-day readmission. Subgroup analysis according to co-presence of reduced or preserved left ventricular ejection fraction (LVEF). Multivariate logistic regression was utilized to detect predictors of poor outcome and difference between subgroups. A total of 127,503 admissions were identified from the database of which 4,717 primary RHF admissions were included in our cohort. There was a trend of increasing RHF diagnosis from 2017 4th Quarter to 2019 4th Quarter. Age, liver disease and reduced LVEF were amongst predictors of in-hospital mortality while iron deficiency anemia and a Charlson Comorbidity Score ≥ 3 were predictors of 30-day readmission. The study of real-world data contributes to a better understanding of RHF outcomes. Further studies are needed to investigate the association between RHF and different types of heart failure and its implications on clinical practice.

Cardiac amyloidosis (CA) often goes unrecognized as a cause of heart failure with preserved ejection fraction (HFpEF). There is paucity of contemporary data evaluating the trends of CA diagnosis and associated sex differences. Adult heart failure hospitalizations were identified from the National Inpatient Sample between 2016 and 2019. Hospitalizations with heart failure other than HFpEF were excluded. Hospitalizations with a diagnosis of CA were identified. A Linear regression was utilized to calculate the trend of CA diagnosis over time. A multivariate logistic regressions analysis was performed to analyze sex differences. There was an increasing trend of CA from 1.2 to 2.3 per 1000 HFpEF admission in the first quarter of 2016 to the fourth quarter of 2019 (P_trend <0.001). In females, as compared to males, there was an increased risk of AIS (6% vs 3%, aOR: 1.68[1.24-2.27], P=0.001) and major bleeding events (10% vs 5%, aOR: 1.97[1.53-2.52], P<0.001). No difference was observed in the in-hospital mortality outcome (8% vs 7%, aOR: 1.2[0.95-1.53], P=0.12) between both groups. Our real-world contemporary analysis showed an increase in CA diagnosis from 2016 to 2019. Despite similar in-hospital mortality, females were associated with higher AIS and major bleeding events rates. Further prospective studies are needed to validate these results.

Ambulatory hemodynamic monitoring has demonstrated the ability to reduce heart failure-related hospitalization, regardless of left ventricular ejection fraction; however, real-world data in a Veterans Affairs patient population are limited. The present study retrospectively reviewed 53 patients with New York Heart Association class III heart failure, regardless of left ventricular ejection fraction, implanted with a pulmonary artery pressure sensor (CardioMEMS) at our single Veterans Affairs institution. Heart failure-related hospitalizations were assessed in patients for 6 and 12 months after the implantation of the device and compared with the 6- and 12- month periods before implantation in the same patient cohort. Pulmonary arterial pressures and medication doses were also recorded at baseline, 6- months, and 12- months and procedural safety data were also assessed. Implantation of a remote pulmonary artery pressure sensor was associated with a 52% (95% confidence interval 30% to 68%, p <0.001) and a 44% (95% confidence interval 24% to 59%, p <0.001) reduction in heart failure-related hospitalization at 6 and 12 months after implant, respectively, compared with the 6- and 12-month preimplant periods. Mean pulmonary arterial pressures also demonstrated significant reductions from baseline to 6 and 12 months after implant. A total of 3 procedure-related adverse events were noted. In conclusion, pulmonary artery pressure sensor implantation is relatively safe and associated with significant reductions in heart failure-related hospitalization and decreased mean pulmonary artery pressures in patients within the Veterans Affairs system with New York Heart Association class III symptoms, regardless of ejection fraction.

CardioMEMS, a remote pulmonary artery pressure monitoring system, provides waveform patterns for the ambulatory heart failure patient. These waveforms provide significant insights into patient volume and clinical management. We aim to provide a foundation for understanding the determinants of waveform characteristics and provide practical examples illustrating how to interpret and integrate common scenario waveforms into clinical decision-making. A total of three groups of relevant scenarios were included namely (a) location and activity at time of waveform transmission, (b) impact of contemporary interventions, and (c) arrhythmias. We illustrate that waveform analysis can be individualized to each patient's care strategy in the appropriate clinical context to help guide clinical decision-making.

The Molecular Microscope Diagnostic System (MMDx) analyzes RNA transcripts of transplanted heart tissue to differentiate among T cell-mediated rejection (TCMR), antibody-mediated rejection (AMR), injury, and healthy tissue. However, little is known about its performance in relation to other modalities in a real-world heart transplant population. We evaluated whether MMDx performs in agreement with other validated modalities. Two hundred and twenty-eight corresponding endomyocardial biopsies (EMBx) and MMDx specimens from 135 adult heart transplant patients were retrospectively reviewed with correlating donor-derived cell-free DNA (dd-cfDNA). Rejection was classified on EMBx in 29 specimens (TCMR ≥ 2R and/or AMR ≥ 1), on MMDx in 56 specimens, and in 74 values with dd-cfDNA ≥0.20%. Despite moderate agreement between EMBx and MMDx (84% agreement, Cohen's kappa, 0.48, p < .001), systematic differences were observed (McNemar's test, p < .001) where MMDx classified 32 of 37 discordant cases as rejection. MMDx and dd-cfDNA demonstrated slight agreement (72% agreement, Cohen's kappa, 0.39, p < .001); however, systematic differences were also apparent where MMDx classified 12 of 50 discordant specimens as rejection when dd-cfDNA was <0.20% (McNemar's test, p < .001). Our findings provide insight on the performance of MMDx relative to other modalities in a heart transplant cohort and have implications on the surveillance and workup of allograft rejection in heart transplantation.