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Does point-of-care viscoelastic testing in patients undergoing left ventricular assist device implantation or orthotopic heart transplantation reduce non-red blood cell transfusion or improve postoperative outcomes?A retrospective observational study.At a single-center tertiary university hospital.Patients undergoing left ventricular assist device placement or heart transplantation INTERVENTIONS: The authors implemented a TEG-based transfusion algorithm to reduce non-red cell transfusion rates compared with historical controls.From May 15, 2019, through March 20, 2020, 68 patients underwent left ventricular assist device placement or heart transplantation. Algorithm adherence was 49.2%. After adjusting for relevant variables, platelet (odds ratio [OR] 0.58 [0.39-0.84]; p = 0.004) and cryoprecipitate (OR 0.37 [0.19-0.72]; p = 0.004) transfusion rates and time to extubation (OR -14.1 [-25.8 to -2.3]; p = 0.020) were significantly reduced compared with historical controls. After adjusting for relevant clinical variables, there was a statistically significant reduction in plasma (median [interquartile range] 0.16 [0.07-0.36], p0.001), platelets (0.06 [0.02-0.21], p0.001), and cryoprecipitate (0.06 [0.01-0.47], p = 0.007) transfusion rates and time to extubation (-16.95 [-27.20 to -6.71], p = 0.002) compared with historical controls.The authors report a statistically significant reduction in transfusion of platelets and cryoprecipitate and time to extubation after adjusting for relevant clinical variables compared with historical controls and a significant reduction in the transfusion of plasma, platelets, and cryoprecipitate and time to extubation in those patients for whom the transfusion algorithm was followed. Their results suggest the importance of implementing transfusion algorithms for patients undergoing heart transplantation and left ventricular assist device placement and of accounting for adherence.

Introduction Sleep related breathing disorders, including central sleep apnea (CSA), are frequent in patients with heart failure however, only limited data is known about the effect of left ventricular assist device (LVAD) placement on OSA and even less about the accuracy of home sleep apnea testing in this population (HSAT). Performing the gold standard polysomnography (PSG) is challenging in this cohort due to logistics, especially during the COVID-19 pandemic. Extending HSAT to the LVAD population would be beneficial, yet initial tests with the WatchPat® were deemed inconclusive. We decided to evaluate the validity of NOX-T3 device for HSAT compared to PSG. Methods This was a single center prospective, observational study that included LVAD patients who screened positive on the STOP-BANG questionnaire. A sleep study was indicated based on consultation with a sleep physician and a standard PSG was ordered. During the PSG, the NOX-T3 was also applied with the results analyzed and compared after test completion. Results In this preliminary analysis, 4 patients (3 male, 1 female) with a LVAD completed a PSG along with the NOX-T3. The overall severity of sleep apnea indicated by apnea hypopnea index during the PSG and the respiratory event index during the NOX-T3 were similar in this small cohort. In 2 of the 4 patients, the oximetry finding (minutes with oxygen saturations at or below 88%) were also similar during both the PSG and the NOX-T3. Conclusion Based on this preliminary analysis, data obtained with the NOX-T3 system were valid and compared well to the standard of care PSG in patients with a LVAD. We plan to enroll at least 10 patients in this ongoing trial, further studies will be needed to validate these results. Performing HSAT with the NOX-T3 in this unique population if PSG is not feasible would be of significant value given the morbidity of sleep apnea in this population. Support (if any)

Background Previous studies have noted significant variation in serum urate (sUA) levels, and it is unknown how this influences the accuracy of hyperuricemia classification based on single data points. Despite this known variability, hyperuricemic patients are often used as a control group in gout studies. Our objective was to determine the accuracy of hyperuricemia classifications based on single data points versus multiple data points given the degree of variability observed with serial measurements of sUA. Methods Data was analyzed from a cross-over clinical trial of urate-lowering therapy in young adults without a gout diagnosis. In the control phase, sUA levels used for this analysis were collected at 2–4 week intervals. Mean coefficient of variation for sUA was determined, as were rates of conversion between normouricemia (sUA ≤6.8 mg/dL) and hyperuricemia (sUA > 6.8 mg/dL). Results Mean study participant (n = 85) age was 27.8 ± 7.0 years, with 39% female participants and 41% African-American participants. Mean sUA coefficient of variation was 8.5% ± 4.9% (1 to 23%). There was no significant difference in variation between men and women, or between participants initially normouricemic and those who were initially hyperuricemic. Among those initially normouricemic (n = 72), 21% converted to hyperuricemia during at least one subsequent measurement. The subgroup with initial sUA n = 54) was much less likely to have future values in the range of hyperuricemia compared to the group with screening sUA values between 6.0–6.8 (n = 18) (7% vs 39%, p = 0.0037). Of the participants initially hyperuricemic (n = 13), 46% were later normouricemic during at least one measurement. Conclusion Single sUA measurements were unreliable in hyperuricemia classification due to spontaneous variation. Knowing this, if a single measurement must be used in classification, it is worth noting that those with an sUA of Trial registration Data from parent study ClinicalTrials.gov Identifier: NCT02038179.

The Revivent TC System (BioVentrix Inc, San Ramon, CA) enables a less invasive approach for left ventricular reshaping and scar exclusion in selected patients with ischemic cardiomyopathy. Although the system is designed to improve quality of life and to promote reverse remodeling, patients can still progress to end-stage heart failure requiring advanced therapies. This report describes a case of left ventricular assist device surgery in a patient 16 months after Revivent System implantation. The planning process and surgical technique proved to be complex. This case report can help provide guidance to advanced heart failure teams who encounter patients with the Revivent System who require left ventricular assist device support.

Purpose To provide safety and outcomes data on LVAD recipients referred for cardiac rehabilitation (CR). Methods A single center continuous-flow LVAD cohort (n=505) was searched for patients with information on CR participation (n=292). The analysis was then limited to LVAD recipients who fit into one of three main CR categories: those who graduated CR (n=138), those who would have been able to participate but declined (n=61), and those who were too sick to complete or start CR (n=28). To assess the association between CR categories and mortality and hospitalizations on LVAD support, multivariate cox regression and negative binomial regression analyses were performed, respectively. Results The mean age of the cohort with CR data available was 59 +/- 14 years, 44% (128/292) were bridge to transplant (BTT), and 40% (114/292) received a HeartMate 3 device. Among those who started CR and had the opportunity to finish (enough follow up time, insurance coverage), 79% graduated. Those who graduated CR had a 96% survival at 1 year (95% CI 91-98). In the unadjusted and adjusted analyses, those who graduated CR had the highest survival and the lowest incidence rates of hospitalization among the CR categories (Table). Conclusion This study is the largest to date to report outcomes of LVAD recipients referred for cardiac rehabilitation. The lower readmission rates and high survival in the group that graduated cardiac rehab provides further evidence for the safety of CR in LVAD recipients.

Background: The impact of pulmonary hypertension (PH) on outcomes after surgical tricuspid valve replacement (TVR) and repair (TVr) is unclear. We sought to characterize PH in patients undergoing TVR/TVr, based on invasive hemodynamics and evaluate the effect of PH on mortality. Methods: We identified 86 consecutive patients who underwent TVR/TVr with invasive hemodynamic measurements within 3 months before surgery. We used Kaplan-Meier survival and restricted mean survival time (RMST) analyses to quantify the effects of PH on survival. Results: The mean age was 63 ± 13 years, 59% were female, 45% had TVR, 55% had TVr, 39.5% had isolated TVR/TVr, and 60.5% had TVR/TVr concomitant with other cardiac surgeries). Eighty-six percent of these patients had PH with a mean pulmonary artery pressure of 30 ± 10 mm Hg, pulmonary vascular resistance (PVR) of 2.5 (interquartile range: 1.5-3.9) Wood units (WU), pulmonary arterial compliance of 2.3 (1.6-3.6) mL/mm Hg, and pulmonary arterial elastance of 0.8 (0.6-1.2) mm Hg/mL. Cardiac output was mildly reduced at 4.0 ± 1.4 L/min, with elevated right-atrial pressure (14 ± 12 mm Hg) and pulmonary capillary wedge pressure (19 ± 7 mm Hg). Over a median follow-up of 6.3 years, 22% of patients died. Patients with PVR ≥ 2.5 WU had lower RMST over 5 years compared with patients with PVR < 2.5 WU. Conclusion: PH is common in patients undergoing TVR/TVr, with combined pre- and postcapillary being the most common type. PVR ≥ 2.5 WU is associated with lower survival at 5-year follow-up. Résumé: Contexte: On connaît mal les répercussions de l’hypertension pulmonaire (HP) chez les patients qui ont subi une intervention chirurgicale de remplacement de la valve tricuspide (RVT) ou de réparation de la valve tricuspide (rVT). Nous avons tenté de caractériser l’HP chez les patients ayant subi un RVT ou une rVT en fonction des paramètres de surveillance hémodynamique effractive et d’évaluer l’effet de l’HP sur la mortalité. Méthodologie: Nous avons relevé 86 patients consécutifs ayant subi un RVT ou une rVT qui avaient fait l’objet de mesures hémodynamiques effractives dans les trois mois précédant l’intervention chirurgicale. Pour quantifier les effets de l’HP sur la survie, nous avons analysé la survie au moyen de la méthode de Kaplan-Meier et de la survie moyenne restreinte. Résultats: Les patients avaient en moyenne 63 ± 13 ans; 59 % d’entre eux étaient des femmes; 45 % avaient subi un RVT et 55 %, une rVT; 39,5 % avaient subi seulement un RVT ou une rVT lors de l’intervention chirurgicale; 60,5 % avaient subi un RVT ou une rVT en même temps qu’une autre intervention cardiaque. Quatre-vingt-six pour cent de ces patients présentaient une HP avec une pression artérielle pulmonaire moyenne de 30 ± 10 mmHg, une résistance vasculaire pulmonaire (RVP) de 2,5 (intervalle interquartile : 1,5 à 3,9) unités de Wood (UW), une compliance artérielle pulmonaire de 2,3 (1,6 à 3,6) ml/mmHg et une élastance artérielle pulmonaire de 0,8 (0,6 à 1,2) mmHg/ml. On a observé une légère baisse du débit cardiaque à 4,0 ± 1,4 L/min, ainsi qu’une augmentation de la pression auriculaire droite (14 ± 12 mmHg) et de la pression artérielle pulmonaire d’occlusion (19 ± 7 mmHg). Sur une période médiane de suivi de 6,3 ans, 22 % des patients sont décédés. Le taux de survie moyenne restreinte à 5 ans était plus faible chez les patients présentant une RVP ≥ 2,5 UW que chez les patients présentant une RVP < 2,5 UW. Conclusion: L’HP est fréquente chez les patients subissant un RVT ou une rVT, le type le plus courant étant l’HP mixte (pré-capillaire et post-capillaire). Une RVP ≥ 2,5 UW est associée à un taux de survie à 5 ans plus faible.

Computational models and three-dimensional prints were developed to aid in the pre-procedural planning of a LVAD exchange surgery. Clinical imaging was used to model and segment the anatomy and implanted device for computational implantation and 3D printing. The physicians visualized the pre-procedural anatomy in a 3D space to better understand the device-tissue-interface of the current implant and assess the optimal location for surgical entry. The models also contributed to the education of the surgical team by providing hands-on tools to understand the planned steps involved in the procedure.

We are all familiar with the following method for constructing an ellipse: Fix two points, f1 and f2, called the foci of the ellipse. Put a thumbtack at f1 and another at f2, and tie a piece of str...

BACKGROUND Our research team obtained a human heart with the right lung attached from a recent transplantation patient via a research collaboration with LifeSource, a local organ procurement organization. The heart and lungs were not viable for transplant given the patient's medical history and were subsequently offered to the University of Minnesota for research purposes. METHODS Using Visible Heart® methodologies, we reanimated the specimen en bloc and collected multimodal direct visualization from inside the cardiac chambers and great vessels of the functioning heart. RESULTS Video footage, using videoscopic and fluoroscopic imaging, was captured and is presented in this report as supporting material. Multiple still images highlight the surgical suture sites of the transplantation procedures. CONCLUSIONS This multimodal imaging offers unique educational value for medical students, clinicians, and medical device designers for improving transplantation techniques and patient outcomes.

Introduction: Transcatheter aortic valve replacement (TAVR) is currently the mainstay of treatment of severe aortic stenosis (AS). We aim to investigate the evolution of transaortic mean gradients in surgical aortic valve replacement (SAVR) patients before and after the Food and Drug Administration (FDA) approval of TAVR. Hypothesis: We assessed the hypothesis that mean gradients across the aortic valve were higher in 2011-2012 before FDA approval of TAVR. Methods: Patients who underwent SAVR in 2011-2012 (n=138) and 2019-2020 (n=134) at the University of Minnesota Medical Center were included. Those with implanted mechanical valves (n=602) were excluded. Valve size and mean aortic gradients were compared between the 2 study groups. Results: Out of 272 patients included in this study, 65.8% were males. Patients underwent SAVR at an older age in 2011-2012 (median 74, IQR 65-82) compared to 2019-2020 (median 67, IQR 60-73). The mean aortic valve gradient post-SAVR was higher in 2011-2012 (median 12, IQR 8-18 vs. median 10, IQR 7-13 in 2019-2020, p=0.016). The median valve size was smaller in 2011-2012 (21 mm vs. 23 mm, p(table) . Conclusion: Patients who underwent SAVR in 2011-2012 were older, more likely to receive smaller valve sizes, and had higher mean aortic valve gradients after SAVR.

Background: Previous studies have noted significant variation in serum urate (sUA) levels, and it is unknown how this influences the accuracy of hyperuricemia classification based on single data points. Despite this known variability, hyperuricemic patients are often used as a control group in gout studies. Our objective was to determine the accuracy of hyperuricemia classifications based on single data points versus multiple data points given the degree of variability observed with serial measurements of sUA.Methods: Data was analyzed from a cross-over clinical trial of urate-lowering therapy in young adults without a gout diagnosis. In the control phase, sUA levels used for this analysis were collected at 2-4 week intervals. Mean coefficient of variation for sUA was determined, as were rates of conversion between normouricemia (sUA ≤6.8 mg/dL) and hyperuricemia (sUA >6.8 mg/dL). Results: Mean study participant (n = 85) age was 27.8 ± 7.0 years, with 39% female participants and 41% African-American participants. Mean sUA coefficient of variation was 8.5% ± 4.9% (1% to 23%). There was no significant difference in variation between men and women, or between participants initially normouricemic and those who were initially hyperuricemic.Among those initially normouricemic (n=72), 15% converted to hyperuricemia during at least one subsequent measurement. The subgroup with initial sUA Conclusion: Single sUA measurements were unreliable in hyperuricemia classification due to spontaneous variation. Those with an sUA of Trial registration: Data from parent study ClinicalTrials.gov Identifier: NCT02038179

Summary Background Among patients with out-of-hospital cardiac arrest (OHCA) and ventricular fibrillation, more than half present with refractory ventricular fibrillation unresponsive to initial standard advanced cardiac life support (ACLS) treatment. We did the first randomised clinical trial in the USA of extracorporeal membrane oxygenation (ECMO)-facilitated resuscitation versus standard ACLS treatment in patients with OHCA and refractory ventricular fibrillation. Methods For this phase 2, single centre, open-label, adaptive, safety and efficacy randomised clinical trial, we included adults aged 18–75 years presenting to the University of Minnesota Medical Center (MN, USA) with OHCA and refractory ventricular fibrillation, no return of spontaneous circulation after three shocks, automated cardiopulmonary resuscitation with a Lund University Cardiac Arrest System, and estimated transfer time shorter than 30 min. Patients were randomly assigned to early ECMO-facilitated resuscitation or standard ACLS treatment on hospital arrival by use of a secure schedule generated with permuted blocks of randomly varying block sizes. Allocation concealment was achieved by use of a randomisation schedule that required scratching off an opaque layer to reveal assignment. The primary outcome was survival to hospital discharge. Secondary outcomes were safety, survival, and functional assessment at hospital discharge and at 3 months and 6 months after discharge. All analyses were done on an intention-to-treat basis. The study qualified for exception from informed consent (21 Code of Federal Regulations 50.24). The ARREST trial is registered with ClinicalTrials.gov, NCT03880565. Findings Between Aug 8, 2019, and June 14, 2020, 36 patients were assessed for inclusion. After exclusion of six patients, 30 were randomly assigned to standard ACLS treatment (n=15) or to early ECMO-facilitated resuscitation (n=15). One patient in the ECMO-facilitated resuscitation group withdrew from the study before discharge. The mean age was 59 years (range 36–73), and 25 (83%) of 30 patients were men. Survival to hospital discharge was observed in one (7%) of 15 patients (95% credible interval 1·6–30·2) in the standard ACLS treatment group versus six (43%) of 14 patients (21·3–67·7) in the early ECMO-facilitated resuscitation group (risk difference 36·2%, 3·7–59·2; posterior probability of ECMO superiority 0·9861). The study was terminated at the first preplanned interim analysis by the National Heart, Lung, and Blood Institute after unanimous recommendation from the Data Safety Monitoring Board after enrolling 30 patients because the posterior probability of ECMO superiority exceeded the prespecified monitoring boundary. Cumulative 6-month survival was significantly better in the early ECMO group than in the standard ACLS group. No unanticipated serious adverse events were observed. Interpretation Early ECMO-facilitated resuscitation for patients with OHCA and refractory ventricular fibrillation significantly improved survival to hospital discharge compared with standard ACLS treatment. Funding National Heart, Lung, and Blood Institute.

Implanting Left ventricular assist devices (LVADs) can be life saving therapies that improve life expectancy for the patients that receive it. The target patient population suffer from end-stage heart failure and are therefore susceptible to morbidities arising from a less than ideal surgical implantation. Importantly, the graft that carries the blood from the LVAD pump to the aorta needs to be sized accordingly so as to not cause any compounding complications. The current typical surgical method, is to perform a visual estimation at the time of implantation. This present study proposes a computational tool that utilizes pre-procedural imaging to better calculate the personalized, ideal, LVAD graft length.

Lung donation is the most risky transplant procedures. With low survival rates, and poor acceptance of donated lungs, those in need of a lung transplant are at high risk of dying. One reason for poor outcomes is the lack of optimal match between donor and recipient when it comes to lung size and shape. Lungs that do not properly fit in the recipient’s chest cavity can fail to inflate fully and quickly start to deteriorate. In such patients, lung contusions can form, edema occurs in healthy lung tissue, and overall lung function declines. To improve patient outcomes after lung transplant, we describe here a developed a computational pipeline which enables donor lungs to be properly matched to recipients. This tool uses CT scans from both the donor and potential recipients to calculate how anatomically different the sets of lungs are, and therefore provide improved matches in both size and shape for the donor lungs.

The mechanisms and degree of myocardial recovery during treatment with venoarterial extracorporeal membrane oxygenation (VA-ECMO) are unclear. We performed a descriptive study to evaluate myocardial recovery and changes in parameters of myocardial loading using echocardiography.We retrospectively evaluated patients with refractory ventricular tachycardia/ventricular fibrillation out-of-hospital cardiac arrest who were treated with the Minnesota Resuscitation Consortium protocol. Left ventricular ejection fraction (LVEF), end-diastolic diameter (LVEDD), end-systolic diameter (LVESD), and fractional shortening were assessed using serial echocardiography. One-way analysis of variance (ANOVA) was used to compare parameters over six hospitalization stages. Two-way ANOVA was used to compare these parameters between patients that survived the index hospitalization and those that died.77 patients had1 echocardiographic turndown evaluations. Thirty-eight patients survived to discharge and 39 patients died. Of 39 in-hospital deaths, 17 patients died before VA-ECMO decannulation and 22 patients died after VA-ECMO decannulation. Among all patients, LVEF improved from 9.7 ± 10.1% from the first echocardiogram after rewarming to 43.1 ± 13.1% after decannulation (p 0.001) and fractional shortening ratio improved from 0.14 ± 0.12 to 0.31 ± 0.14 (p 0.001). The LVEDD and LVESD remained stable (p = 0.36 and p = 0.12, respectively). Patients that died had a lower LVEF by an average of 6.93% (95% confidence interval: -10.0 to -3.83, p 0.001), but other parameters were similar.Refractory cardiac arrest patients treated with VA-ECMO experience significant recovery of ventricular function during treatment. We postulate that this primarily occurs via reduction of LV preload.

Objective The purpose of this study was to determine the relationship between blood product transfusion, with or without recombinant human activated factor VIIa, and survival after lung transplantation. Design Retrospective analysis of a single center with follow-up out to 6 years post-transplantation. Setting Single-center academic lung transplantation program. Participants The study comprised 265 adult patients who underwent single or bilateral sequential lung transplantation from March 2011 to June 2017. Interventions Overall survival using Kaplan-Meier curves was compared among the following 3 cohorts: those not transfused with blood products, those transfused with blood products, and those given blood products and recombinant human activated factor VIIa. Cox proportional hazards regression was used to estimate hazard ratios (HRs), confidence intervals (CIs), and p values. Measurements and Main Results Seventy-eight patients received no packed red blood cell transfusions, 149 received packed red blood cell transfusions, and 38 received both packed red blood cell transfusions and recombinant human activated factor VII. Packed red blood cell transfusion was associated with an increased risk of mortality that did not reach statistical significance (HR 2.168, CI 0.978-4.805; p = 0.057). Additional packed red blood cells beyond 15 U were associated with worsened survival (HR 1.363, CI 1.137-1.633; p = 0.001), but recombinant human activated factor VIIa did not increase the risk of mortality. Conclusion Blood product transfusion during and after lung transplantation is associated with decreased survival, especially with large-volume transfusions. Survival is not worse with recombinant human activated factor VIIa administration, but additional studies are needed to determine whether recombinant human activated factor VIIa administration reduces the need for blood product transfusions.

Objectives: To investigate the baseline risk of patients treated with Extracorporeal Cardiopulmonary Membrane Oxygenation (ECMO) in relation to cannulation strategy and indication for ECMO as well as the relation of cannulation strategy with survival and secondary hospitalization outcomes. Methods: Severity of illness and predicted mortality risk were assessed in 317 patients. Central cannulation was used in 52 patients unable to wean off cardiopulmonary bypass after cardiac surgery. Peripheral cannulation was used in 179 patients for extracorporeal cardiopulmonary resuscitation (eCPR) and in 86 patients who received ECMO for refractory cardiogenic shock (RCS). Results: Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were significantly worse (P

Meticulous attention to detail at the time of surgical implantation can have a significant impact on postoperative outcomes. This chapter describes the authors’ technique for optimal LVAD insertion, along with a brief discussion on some of the concomitant procedures that are frequently required.

Introduction: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used to treat cardiogenic shock and refractory cardiac arrest. However, the degree and mechanisms of myocardial recovery remain unclear. Methods: We retrospectively evaluated myocardial recovery and parameters of myocardial loading with decreasing VA-ECMO support in patients with refractory ventricular tachycardia/ventricular fibrillation (VT/VF) out-of-hospital cardiac arrest treated with the Minnesota Resuscitation Consortium protocol. Results: Of 158 consecutive patients, 58 had interpretable echocardiographic images on > 1 echocardiographic evaluations (age, 54.7±19.3 years). Decannulation was successful in 50 patients (86%); 8 patients (14%) could not be decannulated. Left ventricular ejection fraction (LVEF) was 43.4±14.0% at 10.5±18.0 days after admission in successfully decannulated patients vs 18.1±22.4% at 4.1±2.9 days in patients who were not decannulated ( P P P =0.04). Differences regarding change in LVEF, LV end-systolic diameter, and fractional shortening were not significant (Figure). Conclusion: Patients with refractory VT/VF cardiac arrest who are treated with VA-ECMO experience significant recovery of ventricular function. Changes in myocardial loading patterns suggest that this may occur via decreased transpulmonary flow and left ventricular preload, with little echocardiographic evidence of change in afterload.

Purpose Cardiopulmonary stress testing (CPX) is widely used to evaluate patients with end stage heart failure who may benefit from advanced therapies, such as durable left ventricular assist devices (LVAD). A hypotensive systolic blood pressure response on CPX may identify a subpopulation with the highest risk physiology. We sought to evaluate long term outcomes among LVAD recipients with a pre-implantation hypotensive response. Methods This was a retrospective single center study using consecutive patients implanted with a continuous flow LVAD between 1/2011 and 1/2019 at our Institution. Patients with CPX performed within 12 months before implantation were included. Hypotensive response was defined as a peak exercise systolic blood pressure lower than the resting systolic blood pressure. The primary outcome was 1-year mortality. Multivariable cox regression analysis was performed to evaluate the relationship between hypotensive exercise blood pressure response and mortality. Multivariate linear regression analysis was used to determine pre-implant variables and mortality. Results 313 patients were enrolled in the study and 123 were identified to meet our inclusion criteria. The mean age was 60.1 years, 58% had ischemic cardiomyopathy and 85% were classified as INTERMACS 3-5. 54 patients had a hypotensive response on CPX (44%). A total of 14 patients died at 1 year, 10 from the hypotensive cohort (p=0.043), hazard ratio 3.54 with 95% CI (1.1, 11.3, p=0.033). Post-implantation ICU and overall hospital length of stay were similar to the group with normal blood pressure response. There was also no significant difference in post-operative complications and the risk of re-hospitalization at 1 month, 6 months and 1 year. Conclusion Hypotensive blood pressure response on the CPX performed pre-LVAD implantation is independently associated with increased 1-year mortality. Additional studies are needed to further characterize this high-risk patient population and to identify strategies to improve survival rates.

Purpose Cardiopulmonary stress test (CPX) and right heart catheterization (RHC) are integral part of the routine evaluation for ventricular assist device (LVAD) therapy. A hypotensive response, or failure to augment systolic blood pressure at peak stress above resting values might be a marker of high-risk physiology. We sought to evaluate the association between hypotensive response on CPX and invasive hemodynamics in patients undergoing LVAD evaluation. Methods This was a retrospective single center study of consecutive adult patients who underwent LVAD surgery at our center between 1/2011 and 1/2019. Only patients with both CPX and RHC performed within 12 months of implantation were included. Hypotensive response was defined as a peak exercise systolic blood pressure lower than the resting systolic blood pressure. Central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP) and cardiac index determined using the thermodilution method (CI) were collected from RHC data. Multivariable Cox regression analysis was performed to evaluate the association between CPX data and hemodynamics. Results A total of 313 patients were included in the study and 115 met inclusion criteria. The mean age was 60.1 years, 66% were designated bridge to transplant (BTT) and the majority (85%) were classified as INTERMACS 3-5. Forty seven percent (54/115) developed a hypotensive response during testing. The group had a mean PCWP of 23.7 mmHg and a mean CI of 1.7 L/min/m2. In contrast, patients with normal blood pressure response had a significantly lower PCWP (19.8 mmHg; P=0.011) and significantly higher CI (2.0 L/min/m2; p=0.030). There was no difference in CVP values between the groups. Mean exercise duration was 6 minutes and 1 seconds in the hypotensive group, and 7 minutes 8 seconds in the group with normal blood pressure response. Conclusion A hypotensive response on CPX performed prior to LVAD implantation is associated with more severely abnormal hemodynamics. Identification of this high risk feature earlier has the potential to improve outcomes by preventing late LVAD implantation.

Introduction The allocation system for heart transplantation changed in the United States on October 18, 2018. In this analysis, we report donor quality metrics by UNOS status for patients transplanted under the new allocation system. We suspect higher quality (male, younger, less under-sized) donors will be allocated to patients with the highest acuity UNOS status recipients. Methods Adults (18 years and older) who underwent first-time heart transplantation were identified from the United Network for Organ Sharing (UNOS) registry after October 18, 2018. Donor characteristics by UNOS recipient status then were compared with one-way ANOVA and chi-squared tests, where appropriate. To determine the percent of donors that were under-sized, predicted total ventricular mass for each donors and recipient pair was calculated utilizing previously published models based on age, sex, height, and weight. Under-sizing was defined as a calculated donor mass of more than 10% under the recipient cardiac mass, based on previously reported ideal ranges. Results The analysis included 1,817 patients (Status 1: 141, Status 2: 807, Status 3: 478, Status 4: 319, Status 5: 72). Statistically significant differences were observed across the UNOS status groups, with higher acuity status recipients receiving younger donors with less donor hypertension (Table). Higher acuity status recipients were less likely to receive female donors into male recipients or to be under-sized (Status 1 & 2: 18.7% under-sized vs. Status 3, 4, & 5: 23.8% under-sized, p=0.007). Ischemic times were longer for Status 1 and 2 recipients. Donor alcohol and cocaine use were similar across UNOS statuses. Conclusions Initial analysis reveals that heart transplant recipients with the highest acuity UNOS status are receiving donor hearts with more favorable donor characteristics although with longer ischemic times. More detailed analysis of the donor characteristics and longer follow-up time will be need to further quantify and assess the impact of this measurable variation in donor quality on post-transplant outcomes.

Purpose To assess the performance of several post cardiac surgery vasoplegia definitions in a large, single center continuous-flow left ventricular assist device (CF-LVAD) cohort. Methods A single center first-time, CF-LVAD dataset was utilized for this analysis (n=505). Vasoactive drips and hemodynamics were collected at the following time points in all subjects with available data: pre-op, immediate post-op, and on post-operative days 1, 2, and 3 (n=325). For each of the four vasoplegia definitions tested (table), infusion requirements for each definition were converted to an equivalent vasoactive intropes score (VIS). VIS were then cacluated for each patient, at each time point, and utilzied to determine if vasoplegia criteria were met. To test the assoication between vasoplegia and post LVAD mortality, logistic regression (60-day death as outcome) and cox regression analyses were performed. To assess for clinical predictors of post-opertive vasoplegia, a mutivariable logisitic regression was performed. Results Among the vasoplegia definitions tested, the Patarroyo definition had the strongest association with death at 60 days (OR 3.55, 95 % CI 1.48-8.52, p=0.005). This defintion was met by 14% of cohort subjects with available data. Variables associated with the development of vasoplegia using this definition in the mutivariate models inlcuded higher creatinine, longer cardiopulmonary bypass time, prior cardiothoracic sugery and lower INTERMACS profile. Two of the vasoplegia definitions tested (Levin, Unified) had little utility to classify vasoplegia due to the requirement for mean arterial pressure to be less than 50 mm Hg. Conclusion Among the post-cardiothoracic surgery vasoplegia definitions tested, the Patrroyo was the most highly associated with early post LVAD mortality in this dataset. Risk factors for vasoplegia were similar to previous published reports. Use of VIS simplified the process of determining vasoplegia infusion. criteria

Purpose To assess for a post left ventricular assist device (LVAD) hemodynamic profile predictive of early mortality. Methods A single center first-time, continuous-flow LVAD dataset was utilized for this analysis (n=505). Vasoactive drips and hemodynamics were collected at the following time points in all subjects with available data: pre-op, immediate post-op, and on post-operative days 1, 2, and 3 (n=325). Vasoactive intropes scores (VIS) were calculated at each time point. Trends before and after LVAD were computed and plotted using Locally Estimated Scatterplot Smoothing (LOESS), stratfied by death at 60 days post LVAD implantation. Mutivariate logistic regression and reciever operator curve analyses were performed to test the association between candidate variables and death at 60 days. Results The distinctive hemodynamic feature of patients who experienced death by 60 days was a failure to increase mean arterial pressure (MAP) from the time of leaving the operating room to post-operative day two accompanied by persistently elevated VIS (Figure). A model incorporating post-operative day two VIS, mean arterial pressure and right atrial pressure had an AUC of 78% to predict 60-day death. The group experiencing early mortality had higher measured cardiac indices, lower systemic vascular resistance, and higher right atrial pressures than patients who survived past 60 days, suggesting overlap between classic right ventricular failure and vasoplegia physiology. In this dataset, half of patients who met the criteria for vasoplegia also met criteria for right ventricular failure (21/41, 51%). Conclusion The failure to increase mean arterial pressure accompanied by high doses of inotropic and vasopressor support early after LVAD is highly associated with early mortality. This hemodynamic profile may be more unifying than existing right heart failure and vasoplegia definitions, which appear to have significant overlap. These findings require validation in an external dataset.

Purpose To test the hypothesis that advanced heart failure patients lose weight prior to LVAD, gain weight after LVAD, and that weight loss prior to LVAD is associated with lower pectroralis muscle measures (PMM) quantified on pre operative chest CT scans. Methods The larger cohort for the BMI trend analysis included patients with first-time LVAD implantation at a single center (n=505). The following PMMs were quantified in patients with chest CTs performed within 3 months prior to LVAD implantation (n=194): pectoralis muscle mass indexed to height in meters squared (PMI) and mean Hounsfield units (PHUm). BMI trends before and after LVAD were computed and plotted using Locally Estimated Scatterplot Smoothing (LOESS). BMI prior to LVAD was then regressed longitudinally. The association between BMI trend and PMMs were assessed by including fixed effects for time, PMMs, and their interactions. Results BMI plots are displayed (Figure). For the entire cohort, BMI decreased prior to LVAD, continued to decrease further after LVAD, and then steadily increased. Across PMM tertiles, the same pattern was observed. At 100 days prior to LVAD, both PMMs were significantly associated with BMI (p Conclusion The trend in BMI across the larger cohort before and after LVAD suggests that LVAD recipients are largely sarcopenic at the time of LVAD. The correlation between more rapid weight loss and lower PMMs supports this hypothesis. As muscle wasting is progressive, and lower PMMs are assoiciated with increased post-LVAD mortality, there may be a role in utilizing PMMs to determining optimal implantation timing.

Purpose To model renal function in an advanced heart failure population both prior to and after left ventricular assist device (LVAD) and to determine the association between pre-operative renal function trends and post-LVAD mortality. Methods Patients with a first time continuous-flow LVAD implant at a single center with renal function data before and after LVAD were included in the analysis (n=410). GFR at each time point was calculated with the CKD-EPI equation. Trends before and after LVAD were computed and plotted using Locally Estimated Scatterplot Smoothing (LOESS). GFR between 200 to 100 days prior to LVAD was regressed longitudinally to calculate a slope of GFR change prior to LVAD. Both the GFR slope and nadir of GFR prior to LVAD (Figure) were assessed as predictors of post LVAD mortality using multivariable cox regression. Results When assessed as a whole, GFR declined in the entire cohort prior to LVAD, improved with medical optimization, improved further post LVAD, and then declined again to a level that was similar to initially measured values. Each unit decrease in the GFR slope was associated with an adjusted 35% increase in post LVAD mortality (HR 1.36, 95% CI 1.15-1.51, p=0.002). With respect to the GFR nadir, each 10-unit decrease was associated with an adjusted 19% increase in post-LVAD mortality (HR 1.19, 95% CI 1.07- 1.30, p = 0.003). Models were adjusted for age, bridge to transplant status, ischemic cardiomyopathy, and diabetes. Conclusion This analysis demonstrates that renal function in the advanced heart failure population prior to LVAD is complex, with declines in renal function prior to LVAD, and the nadir of GFR prior to LVAD being associated with increased post LVAD mortality. This data suggest earlier LVAD placement prior to measurable renal deterioration may be beneficial.

Purpose To describe adverse events associated with subclavian access intra-aortic balloon pump (IABP) before and after cardiac transplant utilizing high level, single center data. In order to assess morbidity associated with IABP use, a matched United Network for Organ Sharing (UNOS) cohort without IABP support was created as a comparison group. Methods The study included two patient groups: 1) patients bridged to cardiac transplant as Status 2 with subclavian access IABP at single center and 2) a UNOS cohort of transplant recipients (between 2014-2018) matched on hemodynamic Status 2 requirements and wait times. Patient characteristics and post-transplant outcomes were compared. Complications specific to the subclavian IABP using the single center data were collected and reported. Results The single center subclavian access IABP cohort included 28 patients and was compared to the matched UNOS cohort of 202 patients. There was no significant difference in age, ischemic cardiomyopathy diagnosis, or wait times between the two cohorts (Table 1). Post-transplant length of stay and need for post-transplant dialysis was higher in the IABP supported patients. The one-year survival probabilities were similar (subclavian IABP: 96%, matched UNOS cohort: 93%, log rank p = 0.97). Balloon pump repositioning (36%) and replacement (21%) were common. Post-operative infections attributable to the graft site occurred in 17% of patients. Conclusion Patients transplanted on subclavian access IABP had comparable survival at 1 year to a UNOS matched cohort, however IABP re-positioning, replacement and post-operative infections were common. The matched cohort analysis suggests the IABP itself may be associated with longer length of stay and higher rates of post-transplant dialysis, although patient acuity may have accounted for this difference despite hemodynamic matching.

Purpose Measured glomerular filtration rate (GFR) improves initially after left ventricular assist device (LVAD) implantation and then declines. The reasons for this decline are incompletely understood. We hypothesize that the decline in measured GFR after LVAD is associated with the timing of increasing body mass after surgery. Methods Patients with a first time continuous-flow LVAD implant at a single center with renal function data and body mass index (BMI) data before and after LVAD were included in the analysis (n=410). GFR at each time point was calculated with CKD-EPI equation. Trends before and after LVAD were computed and plotted using Locally Estimated Scatterplot Smoothing (LOESS). Linear mixed effects modeling was performed to test the association between GFR and BMI accounting for correlated, repeated measures within persons. Results Plots of GFR and BMI before and after LVAD implantation are displayed (Figure). BMI decreased prior to LVAD, decreased further after LVAD, and then steadily increased. GFR declined in the cohort prior to LVAD, improved with medical optimization, improved further post LVAD, and then declined again. Across the cohort there was a strong association between GFR and BMI (p Conclusion The displayed trends suggest GFR is over-estimated in the late stages of heart failure and in the immediate post LVAD period due to low creatinine production from sarcopenia. Use of creatinine in the advanced heart failure population may lead to inaccurate GFR estimates. This has broad implications for treatment of the heart failure population.

Purpose The impact of pre-operative acute liver injury on post left ventricular assist device (LVAD) mortality is unknown. Methods The study cohort included adults with first time, continuous-flow LVAD implantation at a single center. Patients with complete laboratory data between -5 and -1 days prior to LVAD were included in the analysis. To assess for patients with acute liver injury pattern, AST and ALT were plotted, log transformed, and smoothed using the Locally Estimated Scatterplot Smoothing (LOESS) function. As AST and ALT tracked together, log AST alone was utilized for the remainder of the analysis. The association between peak and mean log AST prior to LVAD were assessed as predictors of post-LVAD mortality using multivariate cox regression. Results The study cohort consisted of 366 patients. The median age was 58 +/- 14 years old, 54.6% were bridge to transplant (BTT), and 53.3% had ischemic cardiomyopathy. The figure visually demonstrates the pattern of log AST prior to LVAD, stratified by patients who experienced death by 60 days post-implant. In the multivariate analysis, for each 1 unit increase in the peak log AST in the pre-LVAD time period, there was an adjusted 22% increase in post-LVAD mortality (HR 1.22, 95% CI 1.03 - 1.45, p=0.023). For each 1 unit increase in the mean log AST in the pre-LVAD time period, there was an adjusted 30% increase in post-LVAD mortality (HR 1.30, 95% CI 1.05 - 1.61, p=0.016). Models were adjusted for age, sex, BTT status, serum albumin, and ischemic cardiomyopathy. Conclusion Peak AST and higher mean AST levels prior to LVAD implantation were associated with increased post-LVAD mortality, despite improvement in liver injury pattern prior to LVAD. Ongoing organ dysfunction may be part of the mechanism of poor outcomes of patients who have experienced shock prior to LVAD placement.

Let B be a degree- n Blaschke product and, for λ ∈ T , let z 1 , λ , … , z n , λ , ordered according to increasing argument, denote the (distinct) solutions to B ( z ) − λ = 0 . Then there is a smooth curve C such that for each λ the line segments joining z j , λ and z j + 1 , λ are tangent to C . We study the situation in which C is an ellipse and describe the relation to the action of the points z j , λ under elliptic disk automorphisms. These results provide a condition for the numerical range of a compressed shift operator with finite Blaschke symbol to be an elliptical disk. We also consider infinite Blaschke products and the action of parabolic and hyperbolic disk automorphisms.

Purpose To determine the association between ACEI/ARB use and post LVAD mortality in a large, multi-center, contemporary CF dataset inclusive of HeartMate 3 devices. Methods Patients at the two centers with a first time continuous flow (CF) LVAD implant with complete medication and survival outcome data were included in the analysis (total n=648). ACEI/ARB utilization was defined as ACEI or ARB use at discharge or within the first 3 months after LVAD implantation. A mutivariate cox regression was performed to test the association between ACEI/ARB use and post LVAD mortality. Results The mean age of the study cohort was 57 years (+/- 14), 45% were bridge to transplant (BTT), and 13% received HeartMate 3 devices. The median length of follow up for the analysis was 608 days. Sixty six percent of patients were on an ACEI or ARB in the 3 months after LVAD implantation. Use of either an ACEI or ARB was associated with an adjusted 35% reduction in the hazard rate of mortality on LVAD support (adjusted HR 0.65, 95% CI 0.48-0.87, p = 0.004). The final model was adjusted for sex, INTERMACS profile, BTT status, serum creatinine at the time of implant, serum albumin, and BMI. Conclusion ACEI/ARB use was associated with reduced post LVAD mortality in this large, multi-center, contemporary CF dataset inclusive of HeartMate 3 devices. Whether or not tolerating an ACEI or ARB is a marker of a healthier LVAD patient or is the direct cause of improved outcomes remains to be proven.