Digoxin Is Associated With a Decreased Incidence of Angiodysplasia-Related Gastrointestinal Bleeding in Patients With Continuous-Flow Left Ventricular Assist Devices

Gastrointestinal bleeding following Heartmate 3 left ventricular assist device implantation: The Michigan Bleeding Risk Model

BACKGROUND

Gastrointestinal bleeding (GIB) results in frequent hospitalizations and impairs quality of life in durable left ventricular assist device (LVAD) recipients. Anticipation of these events before implantation could have important implications for patient selection and management.

METHODS

The study population included all adult HeartMate 3 (HM3) primary LVAD recipients enrolled in the STS Intermacs registry from January 2017 to December 2020. Using multivariable modeling methodologies, we investigated the relationships between preimplantation characteristics and postimplant bleeding, bleeding and death, and additional bleeding episodes on subsequent bleeding episodes and created a risk score to predict the likelihood of post-LVAD GIB based solely on preimplantation factors.

RESULTS

Of 6,425 patients who received an HM3 LVAD, 1,010 (15.7%) patients experienced GIB. Thirteen preimplantation factors were independent predictors of post-LVAD GIB. A risk score was created from these factors and calculated for each patient. By 3 years postimplant, GIB occurred in 11%, 26%, and 43% of low-, medium- and high-risk patients, respectively. Experiencing 1 post-LVAD GIB event was associated with an increased risk for further GIB events, with 33.9% of patients experiencing at least 1 recurrence. While post-LVAD GIB was associated with mortality, there was no relationship between number of GIB events and death.

CONCLUSIONS

The Michigan Bleeding Risk Model is a simple tool, which facilitates the prediction of post-LVAD GIB in HM3 recipients using 13 preimplant variables. The implementation of this tool may help in the risk stratification process and may have therapeutic and clinical implications in HM3 LVAD recipients.

Evolution of Mechanical Circulatory Support for advanced heart failure

This comprehensive review highlights the significant advancements in Left Ventricular Assist Device (LVAD) therapy, emphasizing its evolution from the early pulsatile flow systems to the cutting-edge continuous-flow devices, particularly the HeartMate 3 (HM3) LVAD. These advancements have notably improved survival rates, reduced complications, and enhanced the quality of life (QoL) for patients with advanced heart failure. The dual role of LVADs, as a bridge-to-transplantation and destination therapy is discussed, highlighting the changing trends and policies in their application. The marked reduction in hemocompatibility-related adverse events (HRAE) with the HM3 LVAD, compared to previous models signifies ongoing progress in the field. Challenges such as managing major infections are discussed, including innovative solutions like energy transfer systems aimed at eliminating external drivelines. It explores various LVAD-associated complications, including HRAE, infections, hemodynamic-related adverse events, and cardiac arrhythmias, and underscores emerging strategies for predicting post-implantation outcomes, fostering a more individualized patient care approach. Tools such as the HM3 risk score are introduced for predicting survival based on pre-implant factors, along with advanced imaging techniques for improved complication prediction. Additionally, the review highlights potential new technologies and therapies in LVAD management, such as hemodynamic ramp tests for optimal speed adjustment and advanced remote monitoring systems. The goal is to automate LVAD speed adjustments based on real-time hemodynamic measurements, indicating a shift towards more effective, patient-centered therapy. The review concludes optimistically that ongoing research and potential future innovations hold the promise of revolutionizing heart failure management, paving the way for more effective and personalized treatment modalities.

When all Else Fails, Try This: The HeartMate III Left Ventricle Assist Device

Heart failure (HF) is a progressive disease. It is estimated that more than 250,000 patients suffer from advanced HF with reduced ejection fraction refractory to medical therapy. With limited donor pool for heart transplant, continue flow left ventricle assist device (LVAD) is a lifesaving treatment option for patients with advanced HF. This review will provide an update on indications, contraindications, and associated adverse events for LVAD support with a summary of the current outcomes data.

Gastrointestinal bleeding and pro-angiogenic shift in the angiopoietin axis with continuous flow left ventricular assist device implantation

BACKGROUND

Gastrointestinal bleeding (GIB) affects up to 40% of continuous-flow left ventricular assist device (CF-LVAD) recipients. A higher risk of GIB is seen in CF-LVAD recipients with lower device pulsatility without a known mechanism. One hypothesis is that the novel hemodynamics in CF-LVAD recipients affect angiogenesis signaling. We aimed to (1) measure serum levels of angiopoietin (Ang)-1, Ang-2, and VEGF-A in CF-LVAD recipients with and without GIB and in healthy controls and (2) evaluate correlations of those levels with hemodynamics.

METHODS

We recruited 12 patients with CF-LVADs (six who developed GIB after device implantation) along with 12 age-matched controls without heart failure or GIB and measured Ang-1, Ang-2, and VEGF-A levels in serum samples from each patient.

RESULTS

CF-LVAD recipients had significantly higher Ang-2 and lower Ang-1 levels compared to controls with no difference in VEGF-A levels. CF-LVAD recipients with GIB had lower Ang-1 levels than those without GIB. There were trends for pulse pressure to be positively correlated with Ang-1 levels and negatively correlated with Ang-2 levels in CF-LVAD recipients with no correlation observed in healthy controls.

CONCLUSION

CF-LVAD recipients demonstrated a shift toward a pro-angiogenic phenotype in the angiopoietin axis that is significantly associated with GIB and may be linked to low pulse pressure.

Repurposing of antiangiogenic agents for treatment of vascular anomalies

Vascular anomalies (VA) are developmental anomalies of veins, arteries, lymphatics or capillaries thought to be caused by mutations in genes that drive angiogenesis. Treatments targeting these genes are limited. We review the literature for conventional medications and products from traditional medicine cultures that have been found to have antiangiogenic activity. Fewer than 50 drugs with credible human activity in VA were identified and include β blockers, monoclonal antibodies, microtubule inhibitors, multi-kinase inhibitors, PIK3CA- and RAS-MAPK pathway inhibitors, and thalidomides. Other drug categories of potential interest are ACE-inhibitors, antifungals, antimalarials, MMP9-inhibitors, and over-the-counter compounds used in Eastern traditional medicine. Low toxicity for some offers the possibility of combined use with known effective agents. In addition to already familiar drugs, others with antiangiogenic capabilities already in use in children or adults may deserve further attention for repurposing for VA.

Association of Angiopoetin-2 and TNF-α With Bleeding During Left Ventricular Assist Device Support: Analysis From the PREVENT Biorepository

The purpose of this study was to describe the changes in plasma levels of angiogenic and inflammatory biomarkers, specifically Ang-2 and TNF-α, in patients receiving HeartMate II (HMII) left ventricular assist device (LVAD) and correlate them with nonsurgical bleeding. It has been shown that angiopoietin-2 (Ang-2) and tissue necrosis factor-α (TNF-α) may be linked to bleeding in LVAD patients. This study utilized biobanked samples prospectively collected from the PREVENT study, a prospective, multicenter, single-arm, nonrandomized study of patients implanted with HMII. Paired serum samples were obtained in 140 patients before implantation and at 90 days postimplantation. Baseline demographics were as follows: age 57 ± 13 years, 41% had ischemic etiology, 82% male, and 75% destination therapy indication. In the 17 patients with baseline elevation of both TNF-α and Ang-2, 10 (60%) experienced a significant bleeding event within 180 days postimplant compared with 37 of 98 (38%) patients with Ang-2 and TNF-α below the mean ( p = 0.02). The hazard ratio for a bleeding event was 2.3 (95% CI: 1.2-4.6) in patients with elevated levels of both TNF-α and Ang-2. In the PREVENT multicenter study, patients with elevations in serum Angiopoietin-2 and TNF-α at baseline before LVAD implantation demonstrated increased bleeding events after LVAD implantation.

Vascular Function in Continuous Flow LVADs: Implications for Clinical Practice

Left ventricular assist devices (LVADs) have been increasingly used in patients with advanced heart failure, either as a destination therapy or as a bridge to heart transplant. Continuous flow (CF) LVADs have revolutionized advanced heart failure treatment. However, significant vascular pathology and complications have been linked to their use. While the newer CF-LVAD generations have led to a reduction in some vascular complications such as stroke, no major improvement was noticed in the rate of other vascular complications such as gastrointestinal bleeding. This review attempts to provide a comprehensive summary of the effects of CF-LVAD on vasculature, including pathophysiology, clinical implications, and future directions.

Left Ventricular Assist Devices: A Primer For the General Cardiologist

Durable implantable left ventricular assist devices (LVADs) have been shown to improve survival and quality of life for patients with stage D heart failure. Even though LVADs remain underused overall, the number of patients with heart failure supported with LVADs is steadily increasing. Therefore, general cardiologists will increasingly encounter these patients. In this review, we provide an overview of the field of durable LVADs. We discuss which patients should be referred for consideration of advanced heart failure therapies. We summarize the basic principles of LVAD care, including medical and surgical considerations. We also discuss the common complications associated with LVAD therapy, including bleeding, infections, thrombotic issues, and neurologic events. Our goal is to provide a primer for the general cardiologist in the recognition of patients who could benefit from LVADs and in the principles of managing patients with LVAD. Our hope is to "demystify" LVADs for the general cardiologist.

Effect of Angiotensin II Antagonism on Gastrointestinal Bleeding in Patients With Left Ventricular Assist Devices: A Systematic Review and Meta-Analysis

The importance of medical therapy to ameliorate the incidence and impact of left ventricular assistance device-related gastrointestinal bleeding has been highlighted recently with several single-center studies. Electronic databases were searched for studies that compared the incidence of gastrointestinal bleeding for those people on left ventricular assist support with and without angiotensin II inhibition. Angiotensin II inhibition was associated with a lower incidence of gastrointestinal bleeding (pooled RR 0.58, 95% confidence interval (CI): 0.34-0.98; p = 0.04], with a trend toward toward lower incidence with arteriovenous malformation-associated gastrointestinal bleeding (pooled RR 0.50, 95% CI: 0.25-1.03; p = 0.06).

Impact of digoxin utilization on clinical outcomes following left ventricular assist device implantation

INTRODUCTION

We aimed to assess the impact of digoxin use following left ventricular assist device (LVAD) implantation on clinical outcomes.

METHODS

Patients implanted with continuous flow LVADs at a single academic medical center and survived to initial hospital discharge were included in the analysis (n = 346). Clinical events were captured at a maximum of 2 years of follow up. Digoxin use was defined as 30-day continuous use post-LVAD. Negative binomial regression and Kaplan-Meier method were used to assess the association between digoxin use and clinical outcomes.

RESULTS

Mean age of the cohort was 56 years (±13) and 23% (79/346) were female sex. Digoxin was used in 144 patients (41.6%) for a median of 268 days (IQR 154, 616). Digoxin use was associated with a significant reduction in cumulative incidence of gastrointestinal bleeding (GIB) (15% vs 26%, p = 0.004). After adjusting for age, hypertension, post-operative hemoglobin, RDW, potassium, and GFR, and use of angiotensin receptor/neprilysin inhibitor, there remained a significant 47% reduction in GIB incidence in patients treated with digoxin. There was no significant difference in cumulative incidence in right ventricular failure (RVF) between the two groups. There was no difference in overall 2-year survival between groups.

CONCLUSIONS

Digoxin use was associated with reduction in GIB events, but not in RVF or mortality. Further studies are needed to confirm these findings and to investigate optimal timing and patient population.

Physiology of Continuous-Flow Left Ventricular Assist Device Therapy

The expanding use of continuous-flow left ventricular assist devices (CF-LVADs) for end-stage heart failure warrants familiarity with the physiologic interaction of the device with the native circulation. Contemporary devices utilize predominantly centrifugal flow and, to a lesser extent, axial flow rotors that vary with respect to their intrinsic flow characteristics. Flow can be manipulated with adjustments to preload and afterload as in the native heart, and ascertainment of the predicted effects is provided by differential pressure-flow (H-Q) curves or loops. Valvular heart disease, especially aortic regurgitation, may significantly affect adequacy of mechanical support. In contrast, atrioventricular and ventriculoventricular timing is of less certain significance. Although beneficial effects of device therapy are typically seen due to enhanced distal perfusion, unloading of the left ventricle and atrium, and amelioration of secondary pulmonary hypertension, negative effects of CF-LVAD therapy on right ventricular filling and function, through right-sided loading and septal interaction, can make optimization challenging. Additionally, a lack of pulsatile energy provided by CF-LVAD therapy has physiologic consequences for end-organ function and may be responsible for a series of adverse effects. Rheological effects of intravascular pumps, especially shear stress exposure, result in platelet activation and hemolysis, which may result in both thrombotic and hemorrhagic consequences. Development of novel solutions for untoward device-circulatory interactions will facilitate hemodynamic support while mitigating adverse events. © 2021 American Physiological Society. Compr Physiol 12:1-37, 2021.

Heart Failure Association of the European Society of Cardiology position paper on the management of left ventricular assist device-supported patients for the non-left ventricular assist device specialist healthcare provider: Part 2: at the emergency department

The improvement in left ventricular assist device (LVAD) technology and scarcity of donor hearts have increased dramatically the population of the LVAD‐supported patients and the probability of those patients to present to the emergency department with expected and non‐expected device‐related and patient–device interaction complications. The ageing of the LVAD‐supported patients, mainly those supported with the ‘destination therapy’ indication, increases the risk for those patients to suffer from other co‐morbidities common in the older population. In this second part of the trilogy on the management of LVAD‐supported patients for the non‐LVAD specialist healthcare provider, definitions and structured approach to the LVAD‐supported patient presenting to the emergency department with bleeding, neurological event, pump thrombosis, chest pain, syncope, and other events are presented. The very challenging issue of declaring death in an LVAD‐supported patient, as the circulation is artificially preserved by the device despite no other signs of life, is also discussed in detail.

Comparison of two individualized antithrombotic protocols in HeartWare HVAD recipients

We previously reported low rates of pump thrombosis and hemorrhagic stroke, but increased bleeding, under our original antithrombosis protocol (P1) in HeartWare recipients. We designed and implemented a revised protocol (P2) to reduce complexity and bleeding. Thrombelastography and PFA-100 guide antiplatelet titration. Goals for P2 were altered to decrease antiplatelet use and anticoagulation intensity. We compared the incidence and rates of gastrointestinal bleeding (GIB), embolic (eCVA) and hemorrhagic (hCVA) stroke, pump thrombosis (PT), and total bleeding (GIB+hCVA), total thrombosis (eCVA+PT), and total events between P1 and P2. Laboratory and medication data were assessed. Patients with and without hemocompatibility-related adverse events (HRAEs) were compared. The study included 123 patients (P1: 65; P2: 58). GIB rate decreased (P1: 0.66; P2 0.30 EPPY, P = .003). CVA rates and incidence were statistically similar, although hCVA incidence increased (P1: 3%; P2: 12%, P = .06). Incidence (P1: 3%; P2: 16%, P = .02) and rate (P1: 0.03; P2: 0.12 EPPY, P = .08) of PT increased. Incidence and rate of overall HRAEs and thrombotic events were similar, while bleeding rate decreased (P1: 0.69; P2: 0.40 EPPY, P = .02). Twelve-month medication burden decreased. Compared to non-HRAE patients, patients with bleeding HRAEs had more antiplatelet and pentoxifylline use, but less statin use; and lower PFAs. Patients with thrombotic HRAEs had less dual antiplatelet use, lower INRs, R-times, and PFA-ADP values. A revised antithrombotic protocol decreased GIB and overall hemorrhagic HRAE rate and medication burden. Unfortunately, PT increased. Non-HRAE and HRAE patients differed in anticoagulation and antiplatelet intensity. These differences will guide the revision of P2.

Impact of heart failure drug therapy on rates of gastrointestinal bleeding in LVAD recipients: An INTERMACS analysis

INTRODUCTION

Gastrointestinal bleeding (GIB) remains a common and vexing complication of left ventricular assist device (LVAD) support. Recent single-center analyses suggest that ACE inhibitors (ACEi)/angiotensin receptor blockers (ARB) and digoxin may prevent GIB in LVAD patients. Here we evaluate the effect of guideline-directed medical therapies (GDMT) for heart failure (HF) on rates of GIB through analysis of the INTERMACS registry database.

METHODS

Thirteen thousand seven hundred thirty-two patients who received a continuous-flow LVAD and were on antiplatelet therapy and anticoagulation with warfarin after 3 months of pump support were included in the analysis. GIB events following implant were assessed based on receipt of ACEi/ARB, beta-blockers (BB), mineralocorticoid receptor antagonist (MRA), amiodarone, digoxin, loop diuretics, and phosphiesterase-5 inhibitors (PDE5). Backwards stepwise cox regression was used to control for confounding of each drug class on each other, as well as for clinical variables like age, gender, renal function, HF etiology, and device strategy.

RESULTS

After 3 months of pump support medications used in LVAD patients were BB (65.0%), ACEi/ARB (51.7%), Amio (43.7%), MRA (37.9%), and loop diuretics (70.1%). In patients with available data, PDE and digoxin use were 18.2% and 16.9%, respectively. The overall incidence of GIB was 19.5% at 2 years of support. After adjustment for other clinical variables, loop diuretics (HR 1.274, p < 0.001) and PDE5 (HR 1.241, p < 0.001) use were associated with increased risk of GIB, while use of BB (HR 0.871, p = 0.006) was associated with lower risk of GIB. ACEi/ARB (HR 1.002, p = 0.971), Amio (HR 1.083, p = 0.106), AA (HR 0.967, p = 0.522) or digoxin (HR 1.087, p = 0.169) did not affect GIB rates on LVAD support (Figure).

CONCLUSION

Despite recent reports, ACEi/ARB, MRA, Amio, and digoxin use does not appear to be associated with GIB during LVAD support. The heightened risk seen in those on loop diuretics may reflect venous congestion in these patients, while antiplatelet effects of PDE5 could drive the higher risk of GIB.

Regulation of Angiopoietin-2 Before and After Mechanical Circulatory Support Therapy

Gastrointestinal bleeding (GIB) during mechanical circulatory support (MCS) is a major unsolved comorbidity. Inadequate activation of angiopoietin-2-related systems is considered as a major cause of GIB. However, the regulation of angiopoietin-2 remains unknown. Consecutive 20 patients who received continuous-flow MCS therapy (MCS group) and 12 with advanced heart failure (HF; HF group) were prospectively enrolled and their angiopoetin-2 levels were compared. Angiopoietin-2 level had a moderate correlation with log10 B-type natriuretic peptide (BNP; r = 0.39, p < 0.001). The MCS group had significantly higher angiopoietin-2 level divided by log10 BNP compared with the HF group (2.80 ± 0.20 vs. 1.88 ± 0.17, p < 0.001). Angiopoetin-2 had a moderate correlation with central venous pressure and C-reactive protein during the MCS support (r = 0.51 and r = 0.45, respectively). Higher angiopoietin-2 level divided by log10 BNP (> 4.3) was significantly associated with the occurrence of GIB with a hazard ratio of 296 (95% confidence interval 2.24-38620, p = 0.0224). Angiopoietin-2 was already elevated in the HF cohort and more elevated following MCS initiation. Among the MCS cohort, angiopoietin-2 was particularly elevated in patients with systemic congestion and inflammation and was associated with higher incidence of GIB.

Primary and Secondary Prevention Strategies for Gastrointestinal Bleeding in Patients with Left Ventricular Assist Device: A Systematic Review and Network Meta-analysis

Recurrent gastrointestinal bleeding (GIB) is a common complication following left ventricular assist device (LVAD) implantation. Our study aimed to estimate the comparative efficacy of different pharmacologic interventions for the prevention of GIB, through a network meta-analysis (NMA). A total of 13 observational studies comparing six strategies. Among those, 4 were for primary, and 9 were for secondary prevention of GIB. On NMA, thalidomide (Hazard ratio [HR]: 0.016, Credible interval [CrI]I: 0.00053-0.12), omega-3-fatty acid (HR:0.088, CrI: 0.026-0.77), octreotide (HR: 0.17, CrI: 0.0589-0.41) and danazol (HR:0.17, CrI: 0.059-0.41) reduced the risk of GIB. The use of angiotensin-converting enzyme inhibitors/angiotensin II receptor blocker (ACEi/ARB) and digoxin were not associated with any significant reduction. Based on NMA, combining indirect treatment comparisons, thalidomide, danazol, and octreotide treatments were associated with decreased risk of recurrent GIB. Additionally, Omega 3 fatty acids were associated with a lower risk of the primary episode of GIB in the LVAD patient population.

Association between digoxin use and gastrointestinal bleeding in contemporary continuous flow left ventricular assist device support

BACKGROUND

Assess the association between digoxin use and gastrointestinal bleeding (GIB) in a multicenter continuous flow left ventricular assist device (LVAD) cohort.

METHODS

Patients implanted with continuous flow LVADs with data on GIB and digoxin use from two centers were included in the analysis (n = 649). GIB events were captured up to 2 years of follow-up. Digoxin use was defined as digoxin prescribed at discharge or within the first 3 months after LVAD implantation. A negative binomial regression model was performed to determine the association between digoxin use and number of GIB events over the follow-up period.

RESULTS

Mean age of the cohort was 57 years (±14) and 45% (293/649) were bridge to transplant (BTT). Digoxin was prescribed in 33% of patients. Digoxin use was associated with an unadjusted 32% reduction in the incidence of rate of all cause GIB (IRR 0.68, 95% CI 0.46-0.99, p = 0.049). After adjusting for age, sex, Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profile, renal function, and implanting center there was still a 34% reduction in the incidence rate (IRR 0.67, 95% CI 0.45-0.99, p = 0.048). When limiting the analysis to those with likely arteriovenous malformation associated GIB, the association strengthened (unadjusted: IRR 0.48, 95 % CI 0.26-0.89, p = 0.02, adjusted: IRR 0.47, 95 % CI 0.25-0.9, p = 0.022).

CONCLUSIONS

In this multicenter study, inclusive of contemporary devices, digoxin use was associated with reduced GIB events. Prospective data will be required to confirm this association.

Pharmacotherapy for durable left ventricular assist devices

Left ventricular assist devices (LVADs) have revolutionized the care of patients with advanced heart failure, yet still require concomitant medications in order to achieve the best possible clinical outcomes. Since the outset of routine placement of durable, continuous-flow LVADs, much of the medication management of these patients to date has been based on International Society of Heart and Lung Transplantation (ISHLT) guidance, most recently published in 2013. Since 2013, numerous multidisciplinary pharmacotherapy publications have increased the LVAD community's understanding of best practices with respect to medications. We identified the major domains of LVAD medication management and conducted a comprehensive search of US National Library of Medicine MEDLINE^® database using keywords chosen to identify medication-related publications of significance dated 2013 or later. Trials pertaining to the HeartMate II™ and the HeartMate™ 3 LVADs (Abbott, Chicago, IL) and the HeartWare™ HVAD™ System (Medtronic, Minneapolis, MN) were chosen for inclusion. Highest priority for inclusion was given to prospective, randomized, controlled studies. Absent these, controlled trials (retrospective or prospective observational) were given next-highest consideration, followed by retrospective uncontrolled studies, and finally case series. Reference lists of qualified publications were reviewed to find any other publications of interest that were not discovered on initial search. Case reports were generally excluded, except where the insight gained was deemed to be uniquely pertinent. This document serves to provide a comprehensive review of the current understanding of optimal medication management in patients with durable, continuous-flow LVADs.

Novel Use of Tamoxifen to Reduce Recurrent Gastrointestinal Bleeding in Patients with Left Ventricular Assist Devices

Gastrointestinal bleeding (GIB) is a frequent complication in patients with continuous-flow left ventricular assist devices (LVAD). We retrospectively evaluated eight patients implanted with a HeartWare LVAD between July 2017 and June 2020 who experienced at least one episode of GIB and were started on tamoxifen 20 mg once daily for secondary prevention. Tamoxifen was associated with a significant decrease in major GIB from a median of 3 (IQR 1.4-7) events/patient-year pre-tamoxifen initiation to 0 (IQR 0-0.9) events/patient-year post-tamoxifen initiation (p = 0.02). Transfusion of packed red blood cells also decreased from 16.8 (IQR 9.9-30.6) units/patient-year pre-tamoxifen initiation to 1.5 (IQR 0-7.5) units/patient-year post-tamoxifen (p = 0.04). Tamoxifen was well tolerated and no thromboembolic complications were observed. This small cohort study suggests that tamoxifen is associated with reduced GIB and transfusion requirements, with no apparent increase in thrombotic risk. A larger, randomized study is warranted to confirm the results of this exploratory analysis. Graphical abstract.

Atrial arrhythmias in patients with left ventricular assist devices

PURPOSE OF REVIEW

Atrial arrhythmias commonly occur in patients with advanced heart failure with reduced ejection fraction (HFrEF) who require left ventricular assist devices (LVADs) implantation. This review summarizes the current literature regarding the incidence, prevalence, and predictors of atrial arrhythmias in LVAD patients and its impact on the clinical outcomes. Moreover, we review the mechanisms and management strategies of atrial arrhythmias in this population.

RECENT FINDINGS

Atrial arrhythmias including atrial fibrillation, atrial flutter, and atrial tachycardia are highly prevalent in patients with advanced HFrEF before or after the LVAD implantation. Atrial arrhythmias have a significant impact on overall clinical outcome including survival, heart failure hospitalization, quality of life, thromboembolic events and resource utilization. Atrial fibrillation and other atrial arrhythmias frequently coexist in this population. In patients with atrial arrhythmias and LVAD, anticoagulation and cardiovascular implantable electronic devices should be closely monitored and managed to prevent thromboembolic events or inappropriate shocks. Rhythm and rate control strategies are comparable regarding overall clinical outcomes in this population. LVADs induce favorable atrial remodeling in patients with HFrEF.

SUMMARY

Atrial arrhythmias are highly common in LVAD patients and have significant impact on overall clinical outcomes. Further studies are needed to determine optimal management and prevention of atrial arrhythmias in LVAD population.

Perioperative improvement in serum albumin level in patients with left ventricular assist device

BACKGROUND

The negative impact of baseline hypoalbuminemia on clinical outcome following left ventricular assist device (LVAD) implantation is well known. However, the implications of perioperative change in serum albumin levels on post-LVAD outcomes remain uninvestigated.

METHODS

Among consecutive patients with baseline serum albumin <3.5 g/dl who received durable LVAD implantation between April 2014 and August 2017 and were followed for 1 year, the impact of perioperative change in serum albumin level from baseline to 3 months post-LVAD on the incidence of adverse events was investigated.

RESULTS

Sixty-eight patients (median 60 years and 69% male) were included. Serum albumin change was an independent predictor of the occurrence of adverse events with an adjusted hazard ratio of 0.32 (95% confidence interval, 0.13-0.78) and a cutoff change of 0.7 g/dl. Those with albumin increase >0.7 g/dl had higher 1-year freedom from adverse events (45% vs. 14%, p = .008), dominantly due to lower incidence of death or sepsis compared with those without (p < .05 for both).

CONCLUSION

Among those with baseline hypoalbuminemia, a considerable perioperative increase in serum albumin levels following LVAD implantation was associated with lower mortality and morbidity. The implication of aggressive nutrition intervention on LVAD patients is the next concern.

A reappraisal of the pharmacologic management of gastrointestinal bleeding in patients with continuous flow left ventricular assist devices

Advancements in the design and functionality of continuous flow left ventricular assist devices (CF-LVADs), as well as a limited number of donor hearts, have resulted in an increased utilization of this therapy among advanced heart failure (HF) patients. Despite these advancements, gastrointestinal bleeding (GIB) remains a common complication after CF-LVAD implantation. The mechanism of GIB in these patients is complex and includes a combination of angiodysplasia, platelet dysfunction, acquired von Willebrand disease, and a variety of patient-specific factors including advanced age and history of GIB. Several pharmacotherapy options have been reported in the literature, though studies supporting the use of these agents are often small, retrospective reports. Within this review, we discuss the various pharmacologic agents, their proposed mechanisms of action, and the available literature pertaining to their effectiveness and tolerability. Additionally, we propose an evidence-based treatment algorithm, encompassing the updated literature, cost of therapy, medication side effects, and ease of administration.

Angiotensin II antagonists and gastrointestinal bleeding in left ventricular assist devices: A systematic review and meta-analysis

Gastrointestinal bleeding (GIB) especially from arteriovenous malformations (AVM) remains one of the devastating complications following continuous-flow left ventricular device (CF-LVAD) implantation. Blockade of angiotensin II pathway using angiotensin-converting enzyme inhibitors (ACEI)/angiotensin receptor blockers (ARB) was reported to mitigate the risk of GIB and AVM-related GIB by suppressing angiogenesis. We performed a systematic review and meta-analysis to evaluate the association between ACEI/ARB treatment and GIB in CF-LVAD population. Comprehensive literature search was performed through December 2019. We included studies reporting risk of GIB and/or AVM-related GIB events in LVAD patients who received ACEI/ARB with those who did not. Data from each study were combined using the random-effects to calculate odd ratios and 95% confidence intervals. Three retrospective cohort studies were included in this meta-analysis involving 619 LVADs patients (467 patients receiving ACEI/ARB). The use of ACEI/ARB was statistically associated with decreased incidence of overall GIB (pooled OR 0.35, 95% CI 0.22-0.56, I² = 0.0%, p < 0.001). There was a non-significant trend toward lower risk for AVM-related GIB in patients who received ACEI/ARB (pooled OR 0.46, 95% CI 0.19-1.07, I² = 51%, p = 0.07). Larger studies with specific definitions of ACEI/ARB use and GIB are warranted to accurately determine the potential non-hemodynamic benefits of ACEI/ARB in CF-LVAD patients.

Left Ventricular Assist Device as Destination Therapy: a State of the Science and Art of Long-Term Mechanical Circulatory Support

PURPOSE OF REVIEW

The purpose of this review is to synthesize and summarize recent developments in the care of patients with end-stage heart failure being managed with a left ventricular assist device (LVAD) as destination therapy.

RECENT FINDINGS

Although the survival of patients treated with LVAD continues to improve, the rates of LVAD-associated complication, such as right ventricular failure, bleeding complications, and major infection, remain high, and management of these patients remains challenging. The durability and hemocompatibility of LVAD support have greatly increased in recent years as a result of new technologies and novel management strategies. Challenges remain in the comprehensive care of patients with destination therapy LVADs, including management of comorbidities and optimizing patient function and quality of life.

Implication of Hemodynamic Assessment during Durable Left Ventricular Assist Device Support

Durable left ventricular assist device therapy has improved survival in patients with advanced heart failure refractory to conventional medical therapy, although the readmission rates due to device-related comorbidities remain high. Left ventricular assist devices are designed to support a failing left ventricle through relief of congestion and improvement of cardiac output. However, many patients still have abnormal hemodynamics even though they may appear to be clinically stable. Furthermore, such abnormal hemodynamics are associated with an increased risk of future adverse events including recurrent heart failure, gastrointestinal bleeding, stroke, and pump thrombosis. Correction of residual hemodynamic derangements post-implantation may be a target in improving longitudinal clinical outcomes during left ventricular assist device support. Automatic and timely device speed adjustments considering a patients' hemodynamic status (i.e., with a smart pump) are potential improvements in forthcoming devices.

Postimplant Phosphodiesterase Type 5 Inhibitors Use Is Associated With Lower Rates of Thrombotic Events After Left Ventricular Assist Device Implantation

Background Left ventricular assist device (LVAD) thrombosis is clinically devastating and impacts the cost effectiveness of LVAD therapy for advanced heart failure. Anticoagulation and antiplatelet therapies represent the standard of care to mitigate LVAD thrombosis. Phosphodiesterase type 5 inhibitors (PDE-5is) exhibit hemodynamic, antiplatelet, and antithrombotic effects. Using a national registry, we examined the relationship of PDE-5i use on thrombotic events in patients with continuous-flow LVADs. Methods and Results We obtained data from 13 772 patients with continuous flow LVADs participating in a national registry. Patients implanted with primary LVADs from 2012 to 2017 were included in the analysis. The primary end point was a composite of LVAD thrombosis and ischemic stroke. Patients were analyzed according to any use of PDE-5i after LVAD implantation (PDE-5i group) versus no use after LVAD implantation (no PDE-5i group). The primary end point was significantly lower in the PDE-5i group compared with the no PDE-5i group (hazard ratio [HR], 0.84; 95% CI, 0.77-0.91; P<0.001) at 48 months. The components of the primary end point (LVAD thrombosis: HR, 0.82; 95% CI, 0.74-0.90; P<0.001; and ischemic stroke: HR, 0.85; 95% CI, 0.75-0.97; P=0.019), as well as the secondary end point all-cause mortality (HR, 0.86; 95% CI, 0.79-0.93; P<0.001) were lower in the PDE-5i group versus the no PDE-5i at 48 months post LVAD. The favorable results observed with postimplant PDE-5i use were consistent with both axial and centrifugal flow devices. Conclusions The postimplant use of PDE-5i was associated with fewer thrombotic events and improved survival in LVAD patients. A randomized clinical trial is warranted to confirm these findings.

Questionable utility of digoxin in left-ventricular assist device recipients: A multicenter, retrospective analysis

Background

While clinical experience with left ventricular assist devices (LVAD) continues to grow and evolve, little is known regarding the ongoing use of certain medications in this population. We sought to evaluate the utility of digoxin in LVAD recipients and its association with outcomes.

Methods

A total of 505 patients who underwent continuous-flow LVAD implantation at 5 centers from 2007–2015 were included. Patients were divided into 4 groups: not on digoxin at any time (ND; n = 257), received digoxin pre implant (PreD; n = 144), received digoxin pre and post implant (ContD; n = 55), and received digoxin only post implant (PostD; n = 49). Survival and all-cause readmission were compared between the 4 groups.

Results

There was no difference in survival at 1 year nor at 3 years between groups (ND = 88%, 66%, respectively; PreD = 85%, 66%; ContD = 86%, 57%; PostD = 90%, 51%; p = 0.7). Readmission per 100 days also was not different between groups (ND = 0.5, PreD = 0.6, ContD = 0.5, PostD = 0.7; p = 0.1).

Conclusions

In this large, multicenter cohort, use of digoxin was not associated with any significant benefit in regard to mortality or hospitalization in patients supported with a continuous-flow LVAD. Importantly, its discontinuation post implant did not worsen all-cause hospitalization or survival.

Left Ventricular Assist Devices (LVADS): History, Clinical Application and Complications

Congestive heart failure is a major cause of morbidity and mortality as well as a major health care cost in the developed world. Despite the introduction of highly effective heart failure medical therapies and simple devices such as cardiac resynchronization therapy that reduce mortality, improve cardiac function and quality of life, there remains a large number of patients who do not respond to these therapies or whose heart failure progresses despite optimal therapy. For these patients, cardiac transplantation is an option but is limited by donor availability as well as co-morbidities which may limit survival post-transplant. For these patients, left ventricular assist devices (LVADs) offer an alternative that can improve survival as well as exercise tolerance and quality of life. These devices have continued to improve as technology has improved with substantially improved durability of the devices and fewer post-implant complications. Pump thrombosis, stroke, gastrointestinal bleeding and arrhythmias post-implant have become less common with the newest devices, making destination therapy where ventricular assist device are implanted permanently in patients with advanced heart failure, a reality and an appropriate option for many patients. This may offer an opportunity for long term survival in many patients. As the first of the totally implantable devices are introduced and go to clinical trials, LVADs may be introduced that may truly be alternatives to cardiac transplantation in selected patients. Post-implant right ventricular failure remains a significant complication and better ways to identify patients at risk as well as to manage this complication must be developed.