NADPH oxidase overexpression and mitochondrial OxPhos impairment are more profound in human hearts donated after circulatory death than brain death.

This study investigated cardiac stress and mitochondrial oxidative phosphorylation (OxPhos) in human donation after circulatory death (DCD) hearts regarding warm ischemic time (WIT) and subsequent cold storage and compared them with that of human brain death donor (DBD) hearts. A total of 24 human hearts were procured for the research study-6 in the DBD group and 18 in the DCD group. DCD group was divided into three groups (n = 6) based on different WITs (20, 40, and 60 min). All hearts received del Nido cardioplegia before being placed in normal saline cold storage for 6 h. Left ventricular biopsies were performed at hours 0, 2, 4, and 6. Cardiac stress [nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits: 47-kDa protein of phagocyte oxidase (p47phox), 91-kDa glycoprotein of phagocyte oxidase (gp91phox)] and mitochondrial oxidative phosphorylation [OxPhos, complex I (NADH dehydrogenase) subunit of ETC (CI)-complex V (ATP synthase) subunit of ETC (CV)] proteins were measured in cardiac tissue and mitochondria respectively. Modulation of cardiac stress and mitochondrial dysfunction were observed in both DCD and DBD hearts. However, DCD hearts suffered more cardiac stress (overexpressed NADPH oxidase subunits) and diminished mitochondrial OxPhos than DBD hearts. The severity of cardiac stress and impaired oxidative phosphorylation in DCD hearts correlated with the longer WIT and subsequent cold storage time. More drastic changes were evident in DCD hearts with a WIT of 60 min or more. Activation of NADPH oxidase via overproduction of p47phox and gp91phox proteins in cardiac tissue may be responsible for cardiac stress leading to diminished mitochondrial oxidative phosphorylation. These protein changes can be used as biomarkers for myocardium damage and might help assess DCD and DBD heart transplant suitability.NEW & NOTEWORTHY First human DCD heart research studied cardiac stress and mitochondrial dysfunction concerning WIT and the efficacy of del Nido cardioplegia as an organ procurement solution and subsequent cold storage. Mild to moderate cardiac stress and mitochondrial dysfunction were noticed in DCD hearts with WIT 20 and 40 min and cold storage for 4 and 2 h, respectively. These changes can serve as biomarkers, allowing interventions to preserve mitochondria and extend WIT in DCD hearts.

Impact of time off anticoagulation in patients with continuous-flow left ventricular assist devices.

Patients with left ventricular assist devices (LVADs) receive anticoagulation to decrease the risk of thrombosis. Various circumstances require discontinuing anticoagulation in LVAD patients, but the risks entailed are not well defined. In a retrospective review of LVAD implantation procedures, we examined the effect of time off anticoagulation on thrombosis and mortality rates after implantation. An international normalized ratio ≤ 1.5 was used to screen for patients taken off anticoagulation. Patients were divided into three groups by the cumulative number of days off anticoagulation: no discontinuation, short-term discontinuation (< 30 days), and long-term discontinuation (≥ 30 days). Rates of ischemic stroke, pump thrombosis, and mortality were compared among groups. Of 245 patients who underwent LVAD implantation during the study, 70 (28.6%) were off anticoagulation during follow-up: 37 (15.1%) had short-term discontinuation (median, 11 days), and 33 (13.5%) had long-term discontinuation (median, 124 days). Patients with long-term discontinuation had a higher rate of ischemic stroke (adjusted hazard ratio 8.5, p = 0.001) and death (adjusted hazard ratio 3.9, p = 0.001). The three groups did not differ in pump thrombosis rate. We conclude that after LVAD implantation, discontinuing anticoagulation for ≥ 30 days is independently associated with an increased risk of ischemic stroke and death.

Outcomes of Heart Transplant Recipients with Class II Obesity: A United Network for Organ Sharing Database Analysis.

BACKGROUND: In the 2016 ISHLT listing criteria guidelines for heart transplantation, recipients were recommended to have a body mass index (BMI) <35 kg/m². However, outcomes data for subgroups of transplant recipients with a BMI >35 kg/m² are limited. We examined the outcomes of heart transplant recipients who had a BMI of 35 to 39.9 kg/m² or ≥40 kg/m² and compared their outcomes with recipients who had a BMI <35 kg/m2. METHODS: Using data from the United Network for Organ Sharing database, we performed a retrospective cohort analysis of 23,009 adults who underwent cardiac transplantation between 2009 and 2018. Transplant recipients were stratified by BMI categories (<35 kg/m², 35-39.9 kg/m², and ≥40 kg/m²). Patient survival was depicted by Kaplan-Meier curves. Cox proportional-hazards modeling was used to determine the prognostic factors associated with mortality within 90 days, 1 year, and 5 years after transplantation. RESULTS: Survival at 90 days, 1 year, and 5 years after transplantation was better in recipients who had a BMI <35 kg/m² than in those who had a BMI of 35 to 39.9 kg/m² (P values ranged from 0.01 to < 0.001) or ≥40 kg/m² (P < 0.001). Additionally, survival at 90 days (P < 0.001) and 1 year (P = 0.002) was significantly better in recipients who had a BMI of 35 to 39.9 kg/m² than in those who had a BMI ≥40 kg/m². In multivariate analysis, a BMI of 35 to 39.9 was significantly associated with increased 90-day mortality (HR = 1.53; 95% CI 1.12, 2.08; P = 0.01) but not increased 1-year (HR = 1.28; 95% CI 0.99, 1.66; P = 0.06) or 5-year mortality (HR = 1.11; 95% CI 0.91, 1.36; P = 0.29). CONCLUSIONS: Although heart transplant recipients with class II obesity (BMI 35-39.9 kg/m²) may have suboptimal survival compared with those who have a BMI <35 kg/m², these patients have better outcomes than do those with class III obesity (BMI ≥40 kg/m²). Thus, contrary to current guidelines, selected patients with class II obesity should be considered for transplantation.

Preoperative hyponatremia and survival after left ventricular assist device implantation.

BACKGROUND: Hyponatremia is associated with adverse outcomes in heart failure and after cardiac surgery. We hypothesized that hyponatremia is associated with poorer short-term and longer term survival in patients after continuous-flow left ventricular assist device (CF-LVAD) placement. METHODS: We reviewed a single-center database of patients who received a CF-LVAD during 2012-2017. Sodium (Na) values obtained within 14 days before CF-LVAD insertion were averaged; patients (n = 332) were divided into hyponatremia (mean Na <135 mEq/L; n = 160; 48.2%) and normonatremia groups (mean Na 135-145 mEq/L; n = 172; 51.8%). Patients requiring preoperative dialysis or pump exchange were excluded. We compared outcomes between preoperative hyponatremia and normonatremia groups. RESULTS: The two groups' baseline characteristics were similar, although hyponatremia patients more often had preoperative mechanical circulatory support (44.4% vs. 31.4%, p = 0.002). Although hyponatremic and normonatremic patients did not differ in 30-day mortality (7.5% vs. 6.5%, p = 0.7), preoperative hyponatremia was associated with greater 5-year mortality (61% vs. 44%, p = 0.03). On binary logistic regression analysis, the strongest independent predictors of late mortality were hyponatremia (odds ratio [OR] 1.88, 95% CI [1.07-3.31], p = 0.02), older age (OR 1.03, 95% CI [1.01-1.05], p = 0.01), and elevated mean right atrial pressure/pulmonary capillary wedge pressure ratio (OR 4.69, 95% CI [1.76-12.47], p = 0.002). CONCLUSIONS: Hyponatremia was not associated with greater early mortality but was associated with poorer late survival. The optimal timing of LVAD implantation in relation to hyponatremia, and whether correcting hyponatremia perioperatively improves long-term survival, should be investigated.

Extracorporeal membrane oxygenation as a bridge to durable left ventricular assist device implantation in INTERMACS-1 patients.

Left ventricular assist devices (LVADs) are increasingly used as destination therapy or as a bridge to future cardiac transplant in patients with end-stage heart failure. Extracorporeal membrane oxygenation (ECMO) can be used to bridge patients in cardiogenic shock or with decompensated heart failure to durable mechanical circulatory support. We assessed outcomes in patients in critical cardiogenic shock (Interagency Registry for Mechanically Assisted Circulatory Support [INTERMACS] profile 1) who underwent implantation of a continuous-flow (CF)-LVAD, with or without preoperative ECMO bridging. For this retrospective study, we selected INTERMACS profile 1 patients who underwent CF-LVAD implantation at our institution between Sep 1, 2004 and Nov 30, 2018. Of 768 patients identified, 133 (17.3%) were INTERMACS profile 1; 26 (19.5%) received preoperative ECMO support, and 107 (80.5%) did not. Postimplantation outcomes were compared between the ECMO and no-ECMO groups. No significant differences were found in 30-day mortality (15.4 vs. 15.9%, P = 0.95) or survival at 1 year (53.8 vs. 60.9%, P = 0.51). Three patients who received ECMO before CF-LVAD implantation subsequently underwent cardiac transplant. In the ECMO group, the lactate level 1 day after ECMO initiation was lower in survivors than nonsurvivors (2.7 ± 2.2 vs. 7.4 ± 4.2 mmol/L, P = 0.02; area under the curve = 0.85, P = 0.01) after CF-LVAD implantation. Bridging with ECMO to CF-LVAD implantation in carefully selected INTERMACS profile 1 patients (those who are at the highest risk for critical cardiogenic shock and for whom palliation may be the only other option) produced acceptable postoperative outcomes.Field of research: Artificial lung/ECMO.

Device exchange from Heartmate II to HeartWare HVAD.

BACKGROUND: Despite technological advancements, pump durability and pump-related complications continue to affect and adversely impact the lives of patients with end-stage heart failure on left ventricular assist device (LVAD) support. In an attempt to avoid recurrent LVAD-related complications, there may be circumstances where it is clinically advantageous to exchange a patient's device from HeartMate II to HeartWare HVAD. However, there is a paucity of data that describes the safety and feasibility of such an approach. OBJECTIVE: We present the largest single-center series of HeartMate II (HMII) to HeartWare (HVAD) device exchanges. METHODS: A retrospective review of 11 patients who underwent HMII to HVAD exchange from 2012 to 2017 was conducted to evaluate patient characteristics, incidence of postoperative complications, and survival. RESULTS: Eleven male patients (mean age 55 ± 14.4 years) underwent HMII to HVAD device exchange. One patient expired on postoperative day 7 secondary to sepsis. One patient was lost-to-follow-up after 23 months. An additional three patients died at 5, 7, and 24 months. Mean follow-up after device exchange was 1555 ± 311 days for the remaining six patients. None of the 11 study patients underwent LVAD explant, further device exchange, or heart transplant. CONCLUSION: Exchange of an HMII LVAD to an HVAD can be performed safely with acceptable perioperative morbidity and mortality.

Tissue valves are preferable for patients with end-stage renal disease: an aggregate meta-analysis.

BACKGROUND: Valve selection in patients with end-stage renal disease (ESRD) is uncertain. We performed a systematic review and meta-analysis to compare clinical outcome in ESRD patients undergoing valve replacement. METHODS: We systematically searched multiple databases (2000-October 2015) to identify original studies comparing adverse events between mechanical and biological valve replacement in ESRD patients. End-points studied were: postoperative mortality, bleeding events, need for re-operation, and late survival. A random-effect inverse-variance weighted analysis was performed; event rates are compared as odds ratio (OR and 95% confidence interval) and hazard ratios (HR) for time-to-event data. Mechanical valve and tissue valve replacement were considered as study and control cohorts, respectively. RESULTS: Fifteen retrospective studies (5523 mechanical and 1600 tissue valve) were included in our meta-analysis. Early mortality was comparable (OR 1.15 [0.77; 1.72]; p = 0.49). The mean follow-up among studies ranged from 1.6-15 years. Bleeding was significantly higher after mechanical valve replacement (OR 2.55 [1.53; 4.26]; p = 0.0003). Structural valve degeneration was present in only 0.6% patients after a tissue valve replacement. Overall survival after valve replacement was poor (median 2.61 years); valve choice did not influence this outcome (pooled HR 0.87 [0.73; 1.04]; p = 0.14). CONCLUSION: Operative mortality in ESRD patients is comparable between mechanical and tissue valve replacement. Major bleeding episodes are significantly higher after mechanical valve replacement but structural degeneration in tissue valves during the follow-up period is low. Based on the findings from this meta-analysis, we would recommend using tissue valves in patients with ESRD.

Kidney Function Trajectories and Right Heart Failure Following LVAD Implantation.

BACKGROUND: Preoperative kidney dysfunction is a risk factor for right heart failure (RHF) after implantation of a left ventricular assist device (LVAD). However, characteristic kidney function trajectories before and after post-LVAD RHF are uncertain, so we investigated this. METHODS AND RESULTS: We identified individuals who received primary continuous-flow LVAD implantation from July 1, 2014 to December 31, 2017 in the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) data set. Incident RHF was ascertained using the INTERMACS definition at 1 and 3 months and classified as transient or persistent. Kidney function trajectories before and after RHF onset, and relationships of baseline kidney function with RHF risk at the different time points, were assessed. We identified 8076 LVAD recipients who met inclusion criteria. Incident RHF was present at 1 month in 26.4%. There were 4850 individuals with follow-up at 3 months, with incident RHF in 4.2%. Kidney function trajectories differed from pre-LVAD implantation to 1-month follow-up by RHF category, with those developing persistent RHF having no improvement in baseline kidney function. For trajectories before the 3-month RHF ascertainment time, the shape was similar for those with and without RHF, with lower estimated glomerular filtration rate levels among those who developed RHF. Baseline estimated glomerular filtration rate levels below the normal range were associated with higher risk of RHF at 1 and 3 months. CONCLUSIONS: In LVAD recipients, preimplantation kidney function and subsequent kidney function trajectories differed substantially by RHF at 1 and 3 months postimplantation, even after adjustment for several confounders. This may demonstrate bidirectional associations between kidney function and right ventricular function in LVAD recipients.

Sex-Based Differences in Patients With Left Ventricular-Assisted Devices and Strokes.

Background: Sex-based differences in clinical outcomes among patients with stroke related to left ventricular assist devices (LVADs) are not well described. Objectives: In this study, the authors examined differences in clinical characteristics and outcomes in men and women who had a stroke during LVAD hospitalization. Methods: The National Inpatient Sample from 2010 and 2019 was used to identify patients with stroke during LVAD hospitalization. Outcomes of interest include inpatient mortality and clinical complications among men vs women. Weighted logistic regression was used to determine the association of sex and outcomes. Adjustments were made for age and the Elixhauser comorbidity index. Results: In total, 35,820 patients underwent LVAD implantation (77% men), and 6.12% (n = 2,192) of patients experienced stroke. Women who had stroke were younger than men who had stroke (mean age in women was 51 years vs men 59 years, P < 0.001). Men with strokes had a higher burden of comorbidities than women. While there were no differences in the odds of ischemic stroke, women had higher odds of hemorrhagic stroke compared to men (OR: 1.49 [95% CI: 1.02-2.18]). Mortality in patients with LVAD who had stroke was significantly higher than in those without stroke. Between 2010 and 2019, stroke rates significantly increased among men, while the trend remained variable among women. Conclusions: In this national cohort, men had a higher comorbidity burden and had worsening stroke trends over the last decade compared to women. Women had fewer LVAD implants and a higher incidence of hemorrhagic stroke. Understanding the factors that contribute to sex-related outcome disparities among LVAD stroke patients is crucial in addressing these diverging trends.

Sex Disparities in Left Ventricular Assist Device Implantation: Delayed Presentation and Worse Right Heart Failure.

We explored whether women undergo continuous-flow left ventricular assist device (CF-LVAD) implantation in later stages of heart failure (HF) than men, evidenced by worse preoperative right HF (RHF). We also compared two propensity models with and without preoperative RHF to assess its effect on outcomes. INTERMACS was queried from July 2008 to December 2017. Propensity model 1 matched men and women on age ≥50 years, HF etiology, body surface area, INTERMACS class, comorbidities, device strategy, temporary mechanical circulatory support, and device type. Model 2 included these variables plus LV end-diastolic diameter, right atrial pressure/pulmonary capillary wedge pressure, pulmonary artery pulsatility index, and right ventricular ejection fraction. The primary outcome was all-cause mortality. Secondary outcomes comprise RHF, rehospitalization, renal dysfunction, stroke, and device malfunction. In model 1, characteristics were comparable between 3,195 women and 3,195 men, except women more often had preoperative RHF and postoperative right VAD support and had worse 1 year and overall survival. In model 2, after propensity matching for additional risk factors for preoperative RHF, 1,119 women and 1,119 men had comparable post-LVAD implant RVAD use and survival. These findings suggest that women present more often with biventricular failure and after implantation have higher RHF and mortality rates.

Predictors and Impact of Prolonged Vasoplegia After Continuous-Flow Left Ventricular Assist Device Implantation.

Background: Vasoplegia after cardiac surgery is associated with adverse outcomes. However, the clinical effects of vasoplegia and the significance of its duration after continuous-flow left ventricular assist device (CF-LVAD) implantation are less known. Objectives: This study aimed to identify predictors of and outcomes from transient vs prolonged vasoplegia after CF-LVAD implantation. Methods: The study was a retrospective review of consecutive patients who underwent CF-LVAD implantation between January 1, 2005, and December 31, 2017. Vasoplegia was defined as the presence of all of the following: mean arterial pressure ≤65 mm Hg, vasopressor (epinephrine, norepinephrine, vasopressin, or dopamine) use for >6 hours within the first 24 hours postoperatively, cardiac index ≥2.2 L/min/m2 and systemic vascular resistance <800 dyne/s/cm5, and vasodilatory shock not attributable to other causes. Prolonged vasoplegia was defined as that lasting 12 to 24 hours; transient vasoplegia was that lasting 6 to <12 hours. Patient characteristics, outcomes, and risk factors were analyzed. Results: Of the 600 patients who underwent CF-LVAD implantation during the study period, 182 (30.3%) developed vasoplegia. Mean patient age was similar between the vasoplegia and no-vasoplegia groups. Prolonged vasoplegia (n = 78; 13.0%), compared with transient vasoplegia (n = 104; 17.3%), was associated with greater 30-day mortality (16.7% vs 5.8%; P = 0.02). Risk factors for prolonged vasoplegia included preoperative dialysis and elevated body mass index. Conclusions: Compared with vasoplegia overall, prolonged vasoplegia was associated with worse survival after CF-LVAD implantation. Treatment to avoid or minimize progression to prolonged vasoplegia may be warranted.

Clinical Predictors and Outcomes After Left Ventricular Assist Device Implantation and Tracheostomy.

BACKGROUND: Postoperative respiratory failure is a major complication that affects up to 10% of patients who undergo cardiac surgery and has a high in-hospital mortality rate. Few studies have investigated whether patients who require tracheostomy for postoperative respiratory failure after continuous-flow left ventricular assist device (CF-LVAD) implantation have worse survival outcomes than patients who do not. OBJECTIVE: To identify risk factors for respiratory failure necessitating tracheostomy in CF-LVAD recipients and to compare survival outcomes between those who did and did not require tracheostomy. METHODS: Consecutive patients who underwent primary CF-LVAD placement at a single institution between August 1, 2002, and December 31, 2019, were retrospectively reviewed. Propensity score matching accounted for baseline differences between the tracheostomy and nontracheostomy groups. Multivariate logistic regression was used to identify tracheostomy risk factors and 90-day survival; Kaplan-Meier analysis was used to assess midterm survival. RESULTS: During the study period, 664 patients received a CF-LVAD; 106 (16.0%) underwent tracheostomy for respiratory failure. Propensity score matching produced 103 matched tracheostomy-nontracheostomy pairs. Patients who underwent tracheostomy were older (mean [SD] age, 57.9 [12.3] vs 54.6 [13.9] years; P = .02) and more likely to need preoperative mechanical circulatory support (61.3% vs 47.8%; P = .01) and preoperative intubation (27.4% vs 8.8%; P < .001); serum creatinine was higher in the tracheostomy group (mean [SD], 1.7 [1.0] vs 1.4 [0.6] mg/dL; P < .001), correlating with tracheostomy need (odds ratio, 1.76; 95% CI, 1.21-2.56; P = .003). Both before and after propensity matching, 30-day, 60-day, 90-day, and 1-year survival were worse in patients who underwent tracheostomy. Median follow-up was 0.8 years (range, 0.0-11.2 years). Three-year Kaplan-Meier survival was significantly worse for the tracheostomy group before (22.0% vs 61.0%; P < .001) and after (22.4% vs 48.3%; P < .001) matching. CONCLUSION: Given the substantially increased probability of death in patients who develop respiratory failure and need tracheostomy, those at high risk for respiratory failure should be carefully considered for CF-LVAD implantation. Comprehensive management to decrease respiratory failure before and after surgery is critical.

The influence of preoperative dialysis on survival after continuous-flow left ventricular assist device implantation.

OBJECTIVES: Dialysis is considered a contraindication to continuous-flow left ventricular assist device (CF-LVAD) implantation. We evaluated clinical outcomes and survival in carefully selected, low-risk patients with renal failure who required dialysis before CF-LVAD implantation. METHODS: We extracted medical record data of patients who underwent CF-LVAD placement at our centre between 1 January 2006 and 31 August 2017, with 2 clinical scenarios: those who required long-term (>14 days) dialysis and those who required short-term (≤14 days) dialysis immediately before implantation. Demographic, clinical and intraoperative characteristics and survival outcomes were assessed. RESULTS: Of 621 patients who underwent CF-LVAD implantation during the study period, 31 underwent dialysis beforehand. Of these, 17 required long-term dialysis (13 haemodialysis, 4 peritoneal dialysis), and 14 underwent short-term haemodialysis. Compared with the long-term dialysis patients, the short-term dialysis patients were more likely to be Interagency Registry for Mechanically Assisted Circulatory Support profile 1-2 (92.9% vs 70.6%; P < 0.001), to have needed preoperative mechanical circulatory support (78.6% vs 70.6%; P < 0.01) and to have higher in-hospital mortality (85.7% vs 29.4%; P = 0.01). Patients stable on long-term dialysis had acceptable overall survival and markedly better 6-month and 1-year survival than those with short-term dialysis before implantation (64.7% vs 14.3% and 58.8% vs 7.1%, respectively; P < 0.001). CONCLUSIONS: Carefully selected patients who are stable on long-term dialysis have acceptable survival rates after CF-LVAD implantation. Patients with acute renal failure had much poorer outcomes than those with chronic end-stage renal disease.

Distinctive kidney function trajectories following left ventricular assist device implantation.

BACKGROUND: The aim of this study was to assess for distinct kidney function trajectories following left ventricular assist device (LVAD) placement. Cohort studies of LVAD recipients demonstrate that kidney function tends to increase early after LVAD placement, followed by decline and limited sustained improvement. Inter-individual differences in kidney function response may be obscured. METHODS: We identified continuous flow LVAD implantations in US adults (2016-2017) from INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support). Primary outcomes were estimated glomerular filtration rate (eGFR) trajectories pre-implantation to ∼12 months. Latent class mixed models were applied to primary and validation samples. Clinical differences among trajectory groups were investigated. RESULTS: Among 4,615 LVAD implantations, 5 eGFR trajectory groups were identified. The 2 largest groups (Groups 1 and 2) made up >80% of the cohort, and were similar to group average trajectories previously reported, with early eGFR rise followed by decline and stabilization. Three novel trajectory groups were found: worsening followed by sustained low kidney function (Group 3, 10.1%), sustained improvement (Group 4, 3.3%), and worsening followed by variation (Group 5, 1.7%). These groups differed in baseline characteristics and outcomes. Group 4 was younger and had more cardiogenic shock and pre-implantation dialysis; Group 3 had higher rates of pre-existing chronic kidney disease, along with older age. CONCLUSIONS: Novel eGFR trajectories were identified in a national cohort, possibly representing distinct cardiorenal processes. Type 1 cardiorenal syndrome may have been predominant in Group 4, and parenchymal kidney disease may have been predominant in Group 3.

Continuous-Flow Left Ventricular Assist Device Support in Patients with Ischemic Versus Nonischemic Cardiomyopathy.

To determine whether the cause of cardiomyopathy affects outcomes in patients who undergo continuous-flow left ventricular assist device support, we compared postimplant adverse events and survival between patients with ischemic and nonischemic cardiomyopathy. The inclusion criteria for the ischemic group were a history of myocardial infarction or revascularization (coronary artery bypass grafting or percutaneous coronary intervention), ≥75% stenosis of the left main or proximal left anterior descending coronary artery, or ≥75% stenosis of ≥2 epicardial vessels. From November 2003 through March 2016, 526 patients underwent device support: 256 (48.7%) in the ischemic group and 270 (51.3%) in the nonischemic group. The ischemic group was older (60.0 vs 50.0 yr), included more men than women (84.0% vs 72.6%), and had more comorbidities. More patients in the nonischemic group were able to have their devices explanted after left ventricular recovery (5.9% vs 2.0%; P=0.02). More patients in the ischemic group had gastrointestinal bleeding (31.2% vs 22.6%; P=0.03), particularly from arteriovenous malformations (20.7% vs 11.9%; P=0.006) and ulcers (16.4% vs 9.3%; P=0.01). Kaplan-Meier analysis revealed no difference in overall survival between groups (P=0.24). Older age, previous sternotomy, higher total bilirubin level, and concomitant procedures during device implantation independently predicted death (P ≤0.03), whereas cause of heart failure did not (P=0.08). Despite the similarity in overall survival between groups, ischemic cardiomyopathy was associated with more frequent gastrointestinal bleeding. This information may help guide the care of patients with ischemic cardiomyopathy who receive continuous-flow left ventricular assist device support.

Effect of Laparoscopic Sleeve Gastrectomy on Heart Transplant Status in 4 Patients with Left Ventricular Assist Devices.

Bariatric surgery helps many morbidly obese patients lose substantial weight. However, few data exist on its long-term safety and effectiveness in patients who also have continuous-flow left ventricular assist devices and in whom heart transplantation is contemplated. We retrospectively identified patients at our institution who had undergone ventricular assist device implantation and subsequent laparoscopic sleeve gastrectomy from June 2015 through September 2017, and we evaluated their baseline demographic data, preoperative characteristics, and postoperative outcomes. Four patients (3 men), ranging in age from 32 to 44 years and in body mass index from 40 to 57, underwent sleeve gastrectomy from 858 to 1,849 days after left ventricular assist device implantation to treat nonischemic cardiomyopathy. All had multiple comorbidities. At a median follow-up duration of 42 months (range, 24-47 mo), median body mass index decreased to 31.9 (range, 28.3-44.3) at maximal weight loss, with a median percentage of excess body mass index lost of 72.5% (range, 38.7%-87.4%). After achieving target weight, one patient was listed for heart transplantation, another awaited listing, one was kept on destination therapy because of positive drug screens, and one regained weight and remained ineligible. On long-term follow-up, laparoscopic sleeve gastrectomy appears to be safe and feasible for morbidly obese patients with ventricular assist devices who must lose weight for transplantation consideration. Additional studies are warranted to evaluate this weight-loss strategy after transplantation and immunosuppression.

Factor Xa inhibitors in patients with continuous-flow left ventricular assist devices.

OBJECTIVE: Warfarin is standard anticoagulation therapy for patients with a continuous-flow left ventricular assist device (CF-LVAD). However, warfarin requires regular monitoring and dosage adjustments and fails for many patients, causing thromboembolic and bleeding events. Factor Xa inhibitors have been shown to be noninferior to warfarin in preventing strokes and are associated with less intracranial hemorrhage in patients with atrial fibrillation. We evaluated treatment safety and effectiveness in CF-LVAD patients who switched from warfarin to a factor Xa inhibitor (apixaban or rivaroxaban) after warfarin failure. METHODS: This was a retrospective, single-center study of patients treated between 2008 and 2018. We assessed the occurrence of stroke, non-central nervous system (CNS) embolism, pump thrombosis, and major gastrointestinal bleeding and intracranial hemorrhage during therapy. RESULTS: We identified seven patients: five were male, the average body mass index was 30 kg/m2, and average age was 56 years. Preimplantation comorbidities included hypertension (all patients) and diabetes mellitus, ischemic cardiomyopathy, atrial fibrillation, and previous myocardial infarction (four patients each). Overall, patients received warfarin for 3968 days and apixaban/rivaroxaban for 1459 days. The warfarin group was within the therapeutic INR range (2.0-3.0) 30% of the time. Complication rates did not differ between warfarin and apixaban/rivaroxaban: strokes, 0.20 vs none, non-CNS embolism, 0.54 vs none; pump thrombosis, 0.27 vs none; major gastrointestinal bleeding, 0.20 vs 0.50; intracranial hemorrhage, 0.13 vs none. CONCLUSIONS: Factor Xa inhibitors may be viable treatment options for CF-LVAD patients for whom warfarin therapy has failed. Large prospective studies are necessary to confirm these results.

Plasmapheresis in Patients With Heparin-induced Thrombocytopenia Requiring Ventricular Assist Device.

Anticoagulation with unfractionated heparin is vital to reduce the risk of thromboembolic events during cardiopulmonary bypass and left ventricular assist device placement. However patients with heparin-induced thrombocytopenia are at risk of developing immune-mediated thrombotic events. We describe 2 patients with heparin-induced thrombocytopenia confirmed via serotonin release assay who were successfully treated with plasmapheresis exchange before left ventricular assist device placement.

Accuracy of Postoperative Risk Scores for Survival Prediction in Interagency Registry for Mechanically Assisted Circulatory Support Profile 1 Continuous-Flow Left Ventricular Assist Device Recipients.

In this study, we sought to determine the accuracy of several critical care risk scores for predicting survival of Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) Profile 1 patients after continuous-flow left ventricular assist device (CF-LVAD) placement. We retrospectively analyzed the records of 605 patients who underwent CF-LVAD implantation between 2003 and 2016. We calculated the preoperative HeartMate II Risk Score (HMRS) and preoperative Right Ventricular Failure Risk Score (RVFRS) and the following risk scores for postoperative days 1-5: HMRS, RVFRS, Model for End-stage Liver Disease (MELD), MELD-eXcluding International Normalized Ratio, Post Cardiac Surgery (POCAS) risk score, Sequential Organ Failure Assessment (SOFA) risk score, and Acute Physiology and Chronic Health Evaluation III. The preoperative scores and the postoperative day 1, 5-day mean, and 5-day maximum scores were entered into a receiver operating characteristic curve analysis to examine accuracy for predicting 30-day, 90-day, and 1-year survival. The mean POCAS score was the best predictor of 30-day and 90-day survival (area under the curve [AUC] = 0.869 and 0.816). The postoperative mean RVFRS was the best predictor of 1-year survival (AUC = 0.7908). The postoperative maximum and mean RVFRS and HMRS were more accurate than the preoperative scores. Both of these risk score measurements of acuity in the postoperative intensive care unit setting help predict early mortality after LVAD implantation.

Outcomes of Repeat Left Ventricular Assist Device Exchange.

Implantable continuous-flow left ventricular assist devices (CF-LVADs) are used for long-term LV support in bridging patients to heart transplantation or as destination therapy. With prolonged support times, some patients will have repeat complications necessitating multiple device exchanges. To elucidate the safety and efficacy of repeat device exchange, we retrospectively reviewed data from 25 patients who underwent two or more CF-LVAD implantations between July 2005 and August 2017. Indications for exchange were thrombus/hemolysis (n = 8, 32%), electromechanical device malfunction (n = 14, 56%), and infection (n = 3, 12%). The implanted devices were the HeartMate II (n = 13, 52%), the HeartWare HVAD (n = 11, 44%), and the Jarvik 2000 (n = 1, 4%). Average hospital length of stay was 44 days (range 4-221 days), and 17 patients (68%) survived to discharge. Average duration of support after the most recent LVAD implantation was 802 days (range 1-3,229 days). Overall survival was 72% at 1 year and 60% at 2 years. Postoperative complications included respiratory failure in five patients (20%), device infection in five (20%), bleeding requiring reoperation in four (16%), neurologic dysfunction in four (16%), and acute renal failure in two (8%). Overall, our data suggest that repeat LVAD exchange is a feasible option for patients with recurrent device-related complications.