Left Ventricular Assist Device Support Research Articles

Tricuspid Valve Reconstruction in Patients with Right Heart Decompensation Due to Severe Tricuspid Regurgitation on LVAD Support

Background/Objectives: Right ventricular (RV) dysfunction after left ventricular assist device (LVAD) implantation is associated with reduced survival and affects duration of hospitalization. Some patients with RV dysfunction on LVAD have significant tricuspid valve regurgitation (TR) with concomitant signs of RV failure. In these cases, tricuspid valve repair (TVR) may minimize clinical signs of RV failure. Methods: We report on two patients (one female, one male) developing significant TR receiving TVR through a right thoracotomy on LVAD support. Results: The time between LVAD implantation and TVR was 4 months and 50 months, respectively. The female patient could be discharged from hospital without TR and any signs of RV dysfunction. The male patient died 13 days later due to septic shock following mesenteric ischemia. At this time, echocardiography showed a competent tricuspid valve. Conclusions: In conclusion, these results provide insight into the clinical judgment of when TVR should be attempted. They suggest whether TVR may be a strategy to avoid hospitalization, minimize the clinical signs of RV insufficiency and improve quality of life in patients on LVAD support with severe TR and clinical signs of right heart dysfunction.

Subaortic Pannus Causing Complete Outlet Obstruction After Bioprosthetic Aortic Valve Replacement in a Patient with Left Ventricular Assist Device: A Case Report

Abstract Background Subaortic pannus formation complicates bioprosthetic aortic valve(AV) replacement. We report an extreme case in a continuous-flow left-ventricular-assist-device(LVAD) patient. Case Summary A 49-year-old Caucasian female with dilated cardiomyopathy was bridged-to-transplant with a HeartWare ventricular-assist-device(HVAD). Duration of support was prolonged, 6-years and 7-months, due to allosensitisation requiring desensitisation. Pump thrombosis occurred 2-years and 4-months post-LVAD requiring alteplase thrombolysis. The patient underwent bioprosthetic AV replacement 3-years and 10-months post-LVAD for symptomatic aortic incompetence. Transthoracic echocardiography(TTE) performed 1-year and 2-years post-bioprosthetic AV replacement repeatedly demonstrated an AV closed during all cardiac cycles without incompetence and nil flow through the left-ventricular-outflow-tract(LVOT). Following transplant, analysis of explanted heart revealed a fused AV. A pannus adherent to the underside of the AV had formed across the entire AV outlet, with complete obliteration of LVOT. This subaortic pannus was not visualised on previous TTE. Histologically, the pannus consisted of hypocellular fibrous tissue with chronic inflammatory cells, spindle histiocytes and myofibroblasts scattered throughout the loose fibromyxoid stroma, the latter highlighted on CD68 immunohistochemical stain(IHC). Partial endothelialisation on the pannus surface was highlighted on ERG & CD31 IHC. Neither calcification, nor signs of acute inflammation were noted. In contrast to previous cases, there was no evidence of associated thrombus macroscopically or microscopically. Discussion Prolonged LVAD support may facilitate subaortic pannus following bioprosthetic AV replacement due to AV closure and altered transvalvular flow. Due to the parallel LVAD circulation, subaortic pannus may develop asymptomatically, without haemodynamic compromise, allowing progression to total LVOT obstruction. This requires consideration prior to LVAD explantation in bridge-to-recovery patients.

Elevated cancer biomarkers in patients with severe heart failure could be a potential predictor of mortality during LVAD support

Abstract Introduction Owing to increasing numbers of heart failure patients a search for new biomarkers predicting prognosis is desirable. Background The purpose of this study was to analyze levels of cancer biomarkers in patients with severe heart failure before or after left ventricular assist device (LVAD) implantation and estimate its impact on survival during LVAD support. Methods We retrospectively analyzed data of all consecutive 168 LVAD recipients (92.8%- male, mean age 53.3 years ( median - 56.6, SD 12.0 ), median INTERMACS profile- 3.0, ischemic etiology of heart failure- 52.4%, 41.0% post CRT-D and 54.8% post ICD implantation, 36.9 post IABP, 5.4% post ECMO%, 11.9% post CABG and 8.9% post other cardiac surgery before LVAD implantation) implanted with continuous-flow LVAD (59.5%-HeartMate3, 35.1%- HeartWare, 5.4%-Heart Mate II) in our institution within years 2009-2023. Among comorbidities 63% of patients had atrial fibrillation or flutter, 41.6%- diabetes, 37.5%- arterial hypertension, 48.8%-renal failure, 7.1% pulmonary obstructive disease, 56.5% had pulmonary hypertension with mean pulmonary artery pressure above 25 mm Hg in right heart catheterization and 47% of patients had a history of cardiac arrest or sustained ventricular arrythmia before LVAD implantation. The overall mortality was 44.0 %. 31% patients were transplanted during LVAD support and in 4 patients (2.3%) LVAD was explanted or deactivated. Patient were followed to death, heart transplantation, LVAD explantation or the end of observation in our institution. Mean time of LVAD support was 885 days (1-2570). 23% of patients had right ventricular failure (RVF) early post LVAD implantation while 7.7% had late form of RVF. Results Serum concentrations of cancer biomarkers: carcinoembryonic antigen (CEA), carbohydrate antigen (CA)19-9, carbohydrate antigen(CA)-125 and alpha fetoprotein (AFP) taken before (56 patients -33.3%) or after (24 patients-14.3%) LVAD implantation were analyzed. Mean values, rate of abnormal results and correlation of abnormal results of CEA, CA19-9, CA-125, AFP with mortality during LVAD support were depicted in Table 1. No statistically significant correlations were found between levels of abovementioned cancer biomarkers and mortality though a trend towards increased mortality could be observed for abnormal results of CEA and Ca 19-9 taken before LVAD implantation. No malignant neoplasms were found in all analyzed patients except of one in whom a recurrence of lymphoma was found 2 months after LVAD implantation. Conclusions Patients with severe heart failure before and after LVAD implantation may present abnormal values of cancer biomarkers despite no found neoplasms. Our observation suggests that elevated cancer biomarker levels could predict mortality in heart failure patients after LVAD implantation. Further research is needed to confirm this thesis and investigate mechanisms of this phenomenon.

The implantation of a left ventricular assist device causes changes in the aortic miRNome and proteome - an integrative analysis

Abstract Background Left ventricular assist devices (LVAD) have been widely used and accepted to treat patients with end-stage heart failure. LVAD non-physiological blood flow velocity, wall shear stress distribution, vorticity current intensity, and vorticity flow generation affect the pathophysiology of vascular changes in aortic tissue. Purpose In this study, we performed multi-omics-based analysis of the aorta to identify molecular markers that could clarify vascular remodeling during LVAD support. Methods Aortic specimens from 48 patients (pair matched samples N=96) were excised during implantation and explantation of LVAD. Small RNA-Seq screening using Next Generation Sequencing and proteomic profile using Data-Independent Acquisition mass spectroscopy were conducted. Experimental and computational approaches, proteomics and transcriptomics data, were integrated and bioinformatics analyses were performed. Results The principal component analysis of miRNome and permutational multivariate analysis of variance of proteomic profile clearly segregated samples before and after LVAD support. We identified a total of 113 differently expressed (DE) miRNAs (61 up-regulated; Padj<0.05 and log2 fold change>|0.5|) after long-term LVAD support. Proteomic analysis identified in total 93 protein significantly changed (47 increased; Padj<0.05 and log2 fold change>|0.5|). Correlation analysis identified strong association between 270 proteins and 66 DE-miRNAs (Padj<0.05 and correlation coefficient>|0.7|). Gene Set Enrichment Analysis revealed, that predicted target genes of DE-miRNAs were mainly engaged in axon guidance, regulation of actin cytoskeleton, endocytosis, and MAP signaling pathway (Padj<0.05). DE-proteins participated mainly in ECM-receptor interaction, focal adhesion, and platelet activation (Padj<0.05). Conclusion Our study presents a network-based method of integrating microRNAs and proteome data and reveals molecular signatures that reflects aortic vascular remodeling due to LVAD treatment.PCA of miRNA DESeq2PCA of protemic profile

Association of gut microbiota imbalance with risk of postoperative infections in patients with left ventricular assist device

Abstract Background Infections are the most common complications following left ventricular assist device (LVAD) implantation and associated with adverse events. Gut microbial imbalance may predispose to mucosal colonization with pathogens, resulting in a risk of subsequent serious infections. However, it remains unclear whether gut microbiota imbalance is associated with postoperative infections in patients with LVAD. Purpose The aim of this study was to investigate whether gut microbiota imbalance was associated with postoperative infections in patients with LVAD. Methods We prospectively examined 22 consecutive LVAD patients who were admitted to a university hospital for routine check-ups and had stool cultures taken between March 2022 and December 2023. All patients had no signs of infection. The patients were divided into two groups according to positive (normal bacterial flora and other bacteria including Streptococcus viridans, Klebsiella, or Extended-spectrum β-lactamase Escherichia coli; n = 7) and negative (normal bacterial flora only; n = 15) for stool culture. The primary outcome was serious infection requiring hospitalisation treated with intravenous antimicrobial agents. Results Patients were predominantly male (68%) and the median age was 49 (interquartile range [IQR] 29-58) years. There were no significant differences in age, sex, primary aetiology of heart failure, type of LVAD devices, time on LVAD support, the history of infection, or antibiotics use within six months between the groups. During a median follow-up period of 316 days (IQR 242-559), the primary outcome occurred in seven patients (32%), including four hospitalisation for driveline infections, two pneumoniae and bacterial bloodstream infections, and one lung abscess and bacterial bloodstream infection. Kaplan–Meier analysis showed that the adverse events more frequently occurred in LVAD patients with positive for stool culture (P = 0.010) (Figure). A multivariable Cox regression analysis showed that positive for stool culture was independently associated with an increased subsequent risk of the primary outcome (hazard ratio 6.99, 95% confidence interval 1.17-41.7, P = 0.033), even after adjustments for age, male, body mass index, diabetes, INTERMACS profile, mechanical circulatory support, serum creatinine, serum albumin, and white blood cell count, which are known to be strong determinants of worse clinical outcomes in patients with LVAD. Conclusions In patients with LVAD, gut microbial imbalance was associated with subsequent serious infections. These findings suggest that the screening of stool culture might be useful for early identification of high-risk patients for infectious complication after LVAD implantation.

Derivation and validation of a multicenter model to identify candidates for advanced HF therapies with high potential to achieve post-LVAD reverse cardiac remodeling

Abstract Background A subset of advanced heart failure (HF) patients can experience significant improvement in their cardiac structure and function while on left ventricular assist device (LVAD) support, which is among the prerequisites for LVAD weaning. Purpose We sought to develop and validate a predictive personalized tool to identify candidates for advanced HF therapies with a high potential to achieve significant improvement in myocardial structure and function post-LVAD. This tool can aid clinicians and patients considering advanced HF therapies options. Methods A total of 884 consecutive LVAD patients were enrolled. The derivation and validation cohorts included 509 patients (from three institutions) and 375 patients from another four institutions), respectively. The primary outcome was "significant reverse remodeling", defined as left ventricular ejection fraction (LVEF) ≥40% and LV end-diastolic diameter ≤6 cm within one year on LVAD support. Bootstrap imputation and LASSO variable selection were used to derive a predictive model which was externally validated. Results Patients were predominantly white (78%), male (80.1%), 57±14 years old. Overall, 12.8% patients were identified as responders. Four variables associated with reverse remodeling were included in the multivariable model achieving a C-statistic of 0.72 (95% CI: 0.66-0.79) in the derivation and 0.75 (95% CI: 0.67-0.84) in the validation cohort (Figure). We created a calculator for individualized prediction of the probability of cardiac recovery and when applied to the studied population, we identified patients with 0.2%-67.6% chance of significant reverse remodeling (see Figure for patient example). Conclusions The Multicenter Recovery Calculator is a predictive tool that provides individualized probability of significant reverse remodeling. This tool may help clinicians and patients to maximize the benefits of both heart transplant and LVAD. Specifically, it may serve to (a) improve patient selection for LVAD as bridge to recovery and (b) benefit transplant waitlist outcomes by prioritizing allocation of donor allografts to patients without a high potential for cardiac reverse remodeling.

The hemodynamic classification system for hemodynamic-related adverse events in left ventricular assist device patients

Abstract Background Durable left ventricular assist device (LVAD) physiology predisposes to right heart failure (RHF) and aortic insufficiency (AI), recently labelled hemodynamic-related adverse events (HDREs). However, the pathophysiology, incidence, and associated morbidity of HDREs remains largely unsettled due to heterogeneity in data reporting. Purpose We sought to validate the recently proposed LVAD Hemodynamic Classification System (HCS) for HDREs. Methods RHF and AI HDREs were retrospectively adjudicated, staged (mild to severe) and phenotyped (isolated or combined RHF/AI-HDREs) based on the HCS assessed at 6-month post-LVAD implant among 183 consecutive patients undergoing LVAD implant at a quaternary heart failure center, and either alive at 6-month on support (n=175) or deceased due to late HDREs 1 to 6 months post-LVAD implant (n=8). The primary outcome was a composite of first HF hospitalization or cardiovascular death between 6 and 24 months after LVAD-implant. Results At 6-month assessment, RHF-HDRE was adjudicated in all patients, while AI-HDRE could not be adjudicated in 22 (12.0%) patients. Overall, 53 (29.0%) patients developed an RHF-HDRE, and 26 (16.0%) an AI-HDRE (phenotypes: 39 isolated RHF, 15 isolated AI, 11 combined RHF-AI, 3 not-adjudicated). During pre-LVAD assessment, age and pulmonary artery pulsatility index were independently associated with RHF-HDRE; and pre-LVAD AI and systolic pulmonary artery pressure with AI-HDRE. Patients developing the combined RHF-AI phenotype required the most intensive bundle of critical care pre-LVAD implantation, had more frequent pre-LVAD RV dysfunction, the highest rate of early post-LVAD RHF, and the most prominent features of suboptimal left ventricular unloading, RV dysfunction, peripheral congestion, renal damage and impaired functional capacity at 6-month assessment. RHF-HDRE (adj-HR 2.69, 95%CI 1.14-6.34, p=0.024), AI-HDRE (adj-HR 4.21, 95%CI 1.70-10.40, p=0.002) and HDRE phenotype (isolated RHF or AI HDRE vs. no HDRE: adj-HR 2.80, 95%CI 1.03-7.62, p=0.044; combined RHF and AI HDRE vs. no HDRE: adj-HR 4.53, 95%CI 1.33-15.35, p=0.015) were associated with the primary outcome. A graded increase in primary outcome was observed with rising RHF and AI stages. Conclusions The LVAD Hemodynamic Classification System for HDREs identifies pathophysiological and clinical clusters of patients with significant prognostic implications. It may help the development of targeted strategies to mitigate HDREs and improve the success of long-term LVAD support.

Reversibility of precapillary pulmonary hypertension and outcomes after heart transplantation bridged with left ventricular assist devices: insight from the UNOS

Abstract Background In light of the updated lowered threshold for diagnosing pulmonary hypertension (PH), the reversibility of precapillary PH with left ventricular assist device (LVAD) and the associated post heart transplantation (HT) outcomes remain unclear. Purpose and methods Using data from the United Network for Organ Sharing database, we aimed to investigate predictors of persistent precapillary PH in HT recipients bridged with LVAD, and examine the interrelated post-HT survival, using the updated pulmonary vascular resistance (PVR) cutoff of >2 WU for precapillary PH. Results Among 2169 HT recipients bridged with LVAD, 1299 had PVR>2 at baseline; 551 (42.4%) of whom normalized their PVR≤2 and 748 (57.6%) remained with elevated PVR>2 after LVAD implantation. Female sex (adjusted odds ratio [aOR] 2.22, 95% confidence interval [CI]:1.61-3.07, p<0.001) and inotropes-treatment at-listing (aOR 1.31, 95% CI: 1.03-1.66, p=0.028) were associated with persistently elevated PVR post LVAD. Conversely, longer duration of LVAD support (aOR 0.74, 95% CI: 0.65-.84, p<0.001) and use of HeartMate 2 (aOR 0.74, CI: 0.59-0. 93, p=0.011) were protective against persistently elevated PVR post-LVAD. Persistently elevated PVR >2 post-LVAD was associated with increased risk of death compared to those who normalized their PVR (adjusted hazard ratio [aHR] 1.26, 95% CI: 1.01-1.57, p=0.037). However, normalized PVR post-LVAD group had comparable survival to those with PVR≤2 at baseline (aHR 0.76, 95% CI: 0.57-1.02, p=0.07). Conclusions Many HT recipients bridged with LVAD remain with PVR>2 post-LVAD implantation, which is associated with increased risk of death post-HT compared to patients with normalized PVR post-LVAD.

Long-term outcomes after percutaneous withdrawal of HeartWare left ventricular assist device (HVAD) support: A 10-year update

Ten years have passed since we reported percutaneous decommissioning of an implantable left ventricular assist device (LVAD) using two Amplatzer vascular plugs in a 17 year-old male who was bridged to recovery after 22 months of LVAD support. Whilst his left ventricular (LV) dimensions never completely normalised and there has been persistent mild impairment of LV systolic function, the patient remains free of heart failure symptoms and his natriuretic peptide level has been well suppressed on guideline-directed medical therapy. He is anticoagulated with Warfarin. There have been no adverse events relating to either the decommissioned LVAD or the percutaneous driveline remnant, or anticoagulation. This case highlights the potential for long-term survival without adverse events in individuals who are left with a redundant implantable LVAD after successful percutaneous withdrawal of mechanical circulatory support.

Comparison of continuous flow centrifugal left ventricular assist devices as a bridge to transplant strategy in a low organ donation environment: single center experience

ObjectiveIn patients with advanced heart failure, heart transplantation is currently the most effective treatment. However, in a low-organ environment, it is usually necessary to proceed in long-term mechanical circulatory support through left ventricular assist device (LVAD) implantation as bridge-to-transplantation. MethodsThe study included all patients with advanced heart failure who underwent continuous flow LVAD implantation as a bridge to transplant strategy in our center (n = 68). Following LVAD implantation and for the period that patients were on LVAD support, pump thrombosis, strokes, gastrointestinal bleeding, and right heart failure occurrence rates were recorded. Outcomes were compared between patients implanted with HeartMate 3 (HM3) and HeartWare LVADs, as well as between patients who did reach heart transplantation (HTx group) and those who did not (noHTx group). ResultsA total of 35 out of 68 patients underwent heart transplantation at a mean time of 691 ± 457 days; 41 received a HeartWare and 27 a HM3 device. HM3 patients had significantly better survival (p = 0.010) and lower complication rates (p = 0.025). In addition, the noHTx group had significantly higher complication rates compared with the HTx group (p = 0.00041). The 5-year estimated Kaplan–Meier survival rate following heart transplantation was 77%. ConclusionPatients with advanced heart failure gain substantial benefit from LVADs awaiting heart transplantation. In a low organ donation environment, the need for reliable LVADs can further improve the outcomes through the reduction of complications provided by current devices.

Bariatric surgery in patients with obesity and end-stage heart failure with left ventricular assist devices: a brief guide

The prevalence of obesity is increasing worldwide, leading to a rise in several comorbidities, and is itself an important risk factor for heart failure. Patients with end-stage heart failure and obesity are often not eligible for heart transplantation (HT) and instead receive cardiac support from left ventricular assist devices (LVAD). In the absence of other contraindications, patients with obesity who are on LVAD support can lose enough weight to later qualify for HT. Bariatric surgery had been explored as an approach for weight loss in this patient population and was found to be a safe and effective option. One recent systematic review and meta-analysis has shown 67.4% of patients with LVAD support are able to be listed for transplantation after bariatric surgery and subsequent weight loss (95%CI: 0.477-0.871). Of these, 32.5% would go on to receive a heart transplant (95%CI: 0.201-0.448). There were also numerous cases of patients whose cardiac function improved after bariatric surgery such that they were delisted for HT and some had subsequent removal of their LVAD. There are many perioperative considerations when evaluating patients with LVADs for bariatric surgery. However, with careful patient selection by a multidisciplinary team and mindful preparation, patients with obesity and end-stage heart failure have an opportunity for longer years of life.

The Society of Thoracic Surgeons Intermacs 2024 Annual Report: Focus on Outcomes in Younger Patients

The 15th Annual Report from The Society of Thoracic Surgeons (STS) Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) includes 29,634 continuous-flow left ventricular assist devices (LVAD) from the 10-year period between 2014 through 2024. The outcomes reported here demonstrate continued improved survival in the current era of fully magnetically levitated (Mag-Lev) devices, with a significantly higher 1-year (85.7% versus 78.4%) and 5-year (59.7% versus 43.7%) survival than those receiving non-Mag-Lev devices. Mag-Lev recipients are experiencing a lower incidence of adverse events, including freedom from GI bleeding (72.6%), device malfunction (82.9%) and stroke (86.7%) at 5 years. Additionally, a focus on a subgroup of patients less than 50 years of age have demonstrated superior outcomes in both survival (91.6% survival at 1 year and 72.6% survival at 5 years) and decreased incidence of adverse events compared to older recipients. This younger cohort also demonstrated more tolerance to the characteristics of sex, race, ethnicity and psychosocial indicators that are associated with worse outcomes following heart transplantation (HT). Based upon these data, a potential net prolongation of life may be realized by considering prolonged LVAD support prior to HT in this population. These analyses provide preliminary data that could positively influence adoption of LVAD technology in groups previously not seen as candidates for this therapy, while providing a more responsible donor allocation strategy for advanced heart failure patients.

Prognostic value of repeated peak oxygen uptake measurements in patients with a left ventricular assist device

BackgroundPeak oxygen uptake (pVO2) predicts mortality in heart failure patients on left ventricular assist device (LVAD) support. This follow-up of the PRO-VAD study examines the prognostic value of repeated pVO2 measurements during long-term follow-up. MethodsThis multicenter follow-up study included patients from the original PRO-VAD cohort who performed a cardiopulmonary exercise test (CPET) twice. Patients were categorized into four groups based on pVO2 levels at the two CPETs: Low at both tests, Low at the first and High at the second test, High at the first and Low at the second test, and High at both tests. Low pVO2 was defined as ≤14 mL/kg/min (or ≤12 mL/kg/min if beta-blocker tolerant), while values above these thresholds were considered High. Survival outcomes were analyzed using the Kaplan-Meier method and cause-specific Cox analysis. ResultsThe study included 152 patients with repeated CPETs at approximately 6 and 12 months following LVAD implantation. The cohort showed slight but significant pVO2 improvement (median change: 0.4 mL/kg/min, P = 0.04). Persistently High pVO2 (76 patients) was associated with a fivefold reduction in mortality hazard (HR 0.20, P = 0.002), compared to persistently Low pVO2 (46 patients). Improvement from Low to High pVO2 (21 patients) displayed similar benefits (HR 0.21, P = 0.02). ConclusionpVO2 measurements remain predictive of mortality upon reiteration in LVAD patients, with changes in pVO2 providing additional prognostic value in identifying patients with an excellent outcome on ongoing LVAD support and in identifying patients requiring further interventions.

Nine Years of Continuous Flow LVAD (HeartMate 3): Survival and LVAD-Related Complications before and after Hospital Discharge.

End-stage heart failure is associated with high mortality. Recent developments such as the left ventricular assist device (LVAD) have improved patient outcomes. The HeartMate 3 LVAD is a novel centrifugal pump that was developed to provide hemodynamic support in heart failure patients, either as a bridge-to-transplant (BTT), myocardial recovery, or destination therapy (DT). Our objective was to evaluate the survival rates and LVAD-related complications of the HeartMate 3 LVAD before and after hospital discharge in our center. We retrospectively reviewed all patients implanted with the HeartMate 3 LVAD in our institute between September 2015 and June 2024. Patients who received a Heart Ware Ventricular Assist Device (HVAD) and HeartMate 2 LVAD devices were excluded. The primary endpoint was survival before and after hospital discharge. The secondary endpoints included an incidence of serious LVAD adverse events (bleeding, major infection, hemolysis, device thrombosis and malfunction, and neurological dysfunction) and the causes of re-admission along the follow-up period. A total of 48 consecutive HeartMate 3 LVAD patients were enrolled in this study. The mean age was 56.1 ± 10.6 years. A total of 72.9% of patients received LVAD therapy as a BTT, 14.6% as DT, 10.4% as a bridge-to-decision, and 2.1% as a bridge-to-recovery. A total of 85.4% of patients were discharged after implantation. The main cause for in-hospital mortality was right ventricular failure (8.3%), followed by stroke, abdominal bleeding, and multi-organ failure (2.1% each). One patient (2.1%) had successful heart transplantation, 26 patients (63.4%) are still on LVAD support, and 11 (26.8%) patients have died during follow-up. The main cause of mortality after hospital discharge was sepsis, which occurred in 9.8% of patients, followed by right ventricular failure, non-LVAD-related causes, unknown causes with two (4.9%) cases each, and one case of fatal stroke (2.4%). During the follow-up, there was no need for LVAD replacement. HeartMate 3 LVAD is associated with excellent in-hospital survival rates in patients with end-stage heart failure. Right ventricular failure was the main cause of death before hospital discharge, whereas sepsis was the main cause of death after hospital discharge.

Aortic regurgitation in left ventricular assist device patients - Does aortic root dilatation contribute to valve incompetence?

Aortic regurgitation (AR) is a known complication after left ventricular assist device (LVAD) implantation potentially leading to recurrent heart failure. Possible pathomechanisms include valvular pathologies and aortic root dilatation. We assessed aortic root dimensions in a group of consecutive LVAD patients who received HeartMate 3. Since 11/2015, we identified 68 patients with no or mild AR at the time of HeartMate 3 implantation who underwent serial echocardiography to assess AR and aortic root dimensions (annulus, sinus, and sinotubular junction). Median follow-up was 40 months (2-94 months). Results were correlated with clinical outcomes. Patients were 60 ± 10 years old, predominantly male (88%) and 35% presented in preoperative critical condition as defined by INTERMACS levels 1 and 2. During follow-up, 23 patients developed AR ≥ II (34%). Actuarial incidence was 8% at 1 year, 29% at 3 years and 41% at 5 years. Echocardiography revealed practically stable root dimensions at the latest follow-up compared to the preoperative state (annulus: 23 ± 3 mm vs. 23 ± 2 mm, sinus: 32 ± 4 mm vs. 33 ± 3 mm, sinotubular junction: 27 ± 3 mm vs. 28 ± 3 mm), irrespective of the development of AR. Serial CT angiograms were performed in 13 patients to confirm echocardiographic findings. Twenty-one patients died during LVAD support leading to a 5-year survival of 71%, showing no difference between patients with and without AR ≥ II (p = 0.573). At least moderate AR develops over time in a substantial fraction of patients (one-third over 3 years). The mechanism does not seem to be related to dilatation of the aortic annulus or root.

The Association Between Pulmonary Vascular Resistance and Posttransplant Outcomes Differs by Left Ventricular Assist Device Status.

Elevated pulmonary vascular resistance (PVR) is a risk factor for mortality after heart transplantation (HT), but whether this association differs for patients with and without left ventricular assist device (LVAD) support before HT is unknown. We analyzed adult first-time HT recipients from the United Network for Organ Sharing (UNOS) registry transplanted between 2010 and 2021. We quantified the association between PVR and the outcomes of 30 day graft failure and 1 year mortality using multivariable logistic regression, stratified by LVAD support status at the time of HT. Pulmonary vascular resistance was modeled using restricted cubic splines to identify clinically relevant risk thresholds. We also examined the association with 10 year survival using multivariable Cox proportional hazards regression. For PVR values less than approximately 2 WU, higher PVR was independently associated with a higher risk of early graft failure (odds ratio [OR] = 1.58, 95% CI: 1.06-2.36) and a higher risk of 1 year mortality (OR = 1.32, 95% CI: 1.10-1.59) among LVAD patients only (interaction p = 0.023 and 0.03, respectively). However, for patients surviving at least 1 year, PVR was not associated with long-term mortality among either subgroup. Whether more aggressive reduction of PVR among HT candidates supported with LVADs can mitigate these risks requires further study.

160: Comparison of Renal Outcomes in Patients Requiring V-A ECMO vs ECMO plus Percutaneous Direct Left Ventricular Assist Device (ECPELLA) Support: A Retrospective Review

160: Comparison of Renal Outcomes in Patients Requiring V-A ECMO vs ECMO plus Percutaneous Direct Left Ventricular Assist Device (ECPELLA) Support: A Retrospective Review

Fibrin clot permeability (Ks) in patients on left ventricular assist device

Patients on left ventricular assist devices (LVAD) are prone to excessive hemostasis disturbances due to permanent contact of artificial pump surfaces with blood components. We aimed to investigate if fibrin clot permeability is altered in patients on long-term continuous-flow LVAD therapy and if the clot permeability is associated with clinical characteristics and adverse events. We investigated 85 end-stage heart failure patients (90.6% men, age 48.6–63.8 years) scheduled for continuous flow long-term LVAD support according to current clinical indications. The patients were assessed periodically: prior to LVAD implantation (T1), 3–6 months (T2) after LVAD implantation, 6–12 months after (T3) and then every 6 months. We tested the first three blood samples (T1-T3) and the last available blood sample (T4), but no longer than 5 years after LVAD implantation. We assessed hemostasis parameters (Activated Partial Thromboplastin Time (APTT) Prothrombin Time, Activated Partial Thromboplastin Time, Fibrinogen, d-dimer, Antithrombin, Thrombin Time, Factor VIII, and von Willebrand Factor, aspirin-induced platelet inhibition, adenosine-diphosphate test) changes during the study period. Fibrin Clot Permeability was evaluated using a pressure system and Permeability Coefficient (Ks) was calculated. We observed a decrease in fibrin clot permeability (Ks) between T1, T2, T3 and T4 time periods; P < 0.01 for each comparison. Fibrin clot permeability was negatively correlated with fibrinogen concentration: r = − 0.51, P < 0.001, factor VIII activity r = − 0.42, P < 0.001. There was no association of Ks with age, Left Ventricular Ejection Fraction (LVEF) and medications P > 0.001, however cumulative measurements in patients on aspirin showed shortening of Ks in this group P = 0.0123. Major adverse cardiac and cerebrovascular events (MACCE) occurred in 36.5% patients, bleeding events in 25.9%, Net Adverse Clinical Events (NACE) in 62.4%; 31.7% patients died, and 17.6% underwent transplantation. The transplantation was considered as the endpoint. Discrepancies in Ks were observed between patients with MACCE, bleeding, and NACE, and patients without adverse events. Ks showed a constant trend towards normalization (P < 0.01) only in patients without adverse events. Patients with advanced heart failure have disturbed clot structure. A trend towards normalization of the Ks values is associated with fewer thromboembolic and bleeding complications in this group of patients.

Aortic Root Vortex Formation During Left Ventricular Assist Device Support.

The vortex that forms in the aortic sinus plays a vital role in optimizing blood flow. Disruption of the vortex can result in flow stagnation and activate thrombus formation in the aortic root, especially when aortic valve flow is reduced as during left ventricular assist device (LVAD) support. Our goal in this study was to visualize vortex formation in an experimental model of the aortic root as flow is progressively reduced. A mock circulatory loop that reproduces heart failure hemodynamics was combined with a HeartMate II LVAD and velocity measured in a transparent aortic root with a bioprosthetic valve. The aortic valve sinus vortices are clearly visible as counter-rotating structures in the velocity field at baseline and for all conditions with flow through the aortic valve. As LVAD speed increases, the central jet narrows but the vortices persist, disappearing only when the valve is completely closed. The vortices preserve fluid momentum and generate shear stress along the tissue surfaces which disrupts flow stasis. These features underscore the importance of maintaining "intermittent" aortic valve opening, as recommended for LVAD patients. This study is the first to report vortex formation in the aortic root during LVAD support, providing a motivation for further evaluation.

Effect of Preoperative Mitral Regurgitation on LVAD Outcomes in Patients with Elevated Pulmonary Vascular Resistance.

In patients with end-stage heart failure who undergo left ventricular assist device (LVAD) implantation, higher pulmonary vascular resistance (PVR) is associated with higher right heart failure rates and ineligibility for heart transplant. Concomitant mitral regurgitation (MR) could potentially worsen pulmonary hemodynamics and lead to worse outcomes; however, its effects in this patient population have not been specifically examined. Using an institutional database spanning November 2003 to August 2017, we retrospectively identified patients with elevated PVR who underwent LVAD implantation. Patients were stratified by concurrent MR: moderate/severe (PVR + MR) vs. mild/none (PVR - MR). Cumulative incidence functions and Fine-Gray competing risk regression were performed to assess the effect of MR on heart transplant rates and overall survival during index LVAD support. Of 644 LVAD recipients, 232 (171 HeartMate II, 59 HeartWare, 2 HeartMate III) had baseline PVR > 3 Woods units; of these, 124 (53%) were INTERMACS 1-2, and 133 (57%) had moderate/severe MR (≥ 3 +). Patients with PVR + MR had larger a baseline left ventricular end-diastolic diameter than patients with PVR - MR (87.9 ± 38.2 mm vs. 75.9 ± 38.0 mm; P = 0.02). Median clinical follow-up was 18.8 months (interquartile range: 4.7-36.4 months). Moderate/severe MR was associated with lower mortality rates during index LVAD support (adjusted hazard ratio 0.64, 95% CI 0.41-0.98; P = 0.045) and higher heart transplant rates (adjusted odds ratio 2.86, 95% CI 1.31-6.25; P = 0.009). No differences in stroke, gastrointestinal bleeding, or right heart failure rates were observed. Among LVAD recipients with elevated preoperative PVR, those with moderate/severe MR had better overall survival and higher transplant rates than those with mild/no MR. These hypothesis-generating findings could be explained by incremental LVAD benefits resulting from reduction of MR and better LV unloading in a subset of patients with larger ventricles at baseline. In patients with preoperative elevated PVR, MR severity may be a prognostic sign that can inform patient selection for end-stage heart failure therapy.