Gastrointestinal Bleeding in Left Ventricular Assist Device: Octreotide and Other Treatment Modalities. ASAIO J. 2018;64:433-439. [PMID: 29406356 DOI: 10.1097/mat.0000000000000758]

Time-varying analyses of survival and outcomes in patients with HeartMate 3 left ventricular assist devices

AIMS

As patients experience longer survival on HeartMate 3 left ventricular assist devices, there is a need to characterize long-term risks of adverse outcomes more precisely. This study characterized temporal variations in risks of mortality and adverse outcomes in patients with a HeartMate 3.

METHODS AND RESULTS

From October 2015 to January 2023, 431 HeartMate 3 devices were implanted at Cleveland Clinic. Survival was estimated to 5 years post-implant. Time-varying risks of death, neurological events, gastrointestinal bleeding, device-related infections, and other adverse events were characterized using multiphase hazard modelling. Survival on HeartMate 3 at 1 and 5 years was 88% and 58%, respectively. Risk of death peaked in the first postoperative month before declining rapidly to a constant, lower hazard. Cumulative number of neurological events/patient at 1 year and 5 years was 0.13 and 0.29, respectively; risk was highest within the first postoperative week, then rapidly declined by 1 month. Cumulative number of gastrointestinal bleeding events/patient at 1 year and 5 years was 0.32 and 0.78, respectively; risk was highest within 1 week postoperatively and gradually declined to a constant risk over the first year. Device-related infections developed in 136 patients. One- and 5-year freedom from device-related infection was 77% and 45%, respectively; risk was initially low before peaking at 6 months postoperatively and then gradually declining to a steady hazard.

CONCLUSION

Long-term survival on HeartMate 3 support was favourable in a large single-centre cohort. Strategies to reduce early postoperative risk of neurological events and late risks of gastrointestinal bleeding, infections and other adverse events are needed.

Back Up at the Pump? I Have a Gut Feeling About This: A Review of the Gastrointestinal Manifestations From Congestive Heart Failure

Heart failure, which is a clinical syndrome characterized by the heart's inability to maintain adequate cardiac output, is known to affect various organ systems in the body due to its ischemic nature and activation of the systemic immune response, but the resultant complications specifically on the gastrointestinal tract and the liver are not well discussed and poorly understood. Gastrointestinal-related phenomena are common symptoms experienced in patients with heart failure and frequently found to increase morbidity and mortality in these populations. The relationship between the gastrointestinal tract and heart failure are strongly linked and influence each other much so that the bidirectional association of the two is oftentimes referred to as cardiointestinal syndrome. Manifestations include gastrointestinal prodrome, bacterial translocation and protein-losing gastroenteropathy by gut wall edema, cardiac cachexia, hepatic insult and injury, and ischemic colitis. More attention is needed from a cardiology perspective to recognize these common presenting gastrointestinal phenomena that affect much of our patient population with heart failure. In this overview, we describe the association between heart failure and the gastrointestinal tract, the pathophysiology, lab findings, clinical manifestations and complications, and the management involved.

How to diagnose and manage emergency medical conditions in patients on left ventricular assist device support: A clinician's field guide

Left ventricular assist devices (LVADs) have revolutionized the treatment of advanced heart failure, providing mechanical circulatory support for patients awaiting heart transplantation or as destination therapy. However, patients on LVAD support are susceptible to a range of emergency medical conditions that require prompt recognition, intervention, and multidisciplinary management. This review paper aims to provide an algorithmic approach and a field guide on the diagnosis and management of emergency medical conditions in LVAD patients, including LVAD alarms, gastrointestinal bleeding, cerebrovascular accidents, pump thrombosis and obstruction, unresponsiveness, and electrical shock by the defibrillator. By understanding the mechanisms, clinical presentation, diagnostic evaluation, and therapeutic strategies associated with these conditions, healthcare providers can improve patient outcomes and optimize LVAD care.

Impact of statins on incidence of gastrointestinal bleeding events among patients with continuous-flow left ventricular assist devices

BACKGROUND

Patients with continuous flow left ventricular assist devices (CF-LVADs) are at increased risk of gastrointestinal bleeding (GIB). Statins are commonly prescribed in LVAD patients for cardiovascular disease prevention. However, their impact on GIB events is controversial. Importantly, literature regarding statins impact on GIB in CF-LVAD patients is lacking.

METHODS

A single-center, retrospective review of adult patients who underwent CF-LVAD implantation between May 2016 and January 2020 was performed. Patients were categorized based on statin use throughout the study period. The primary outcome was the composite of arteriovenous malformation confirmed GIB and major GIB events for up to 1-year post-LVAD implantation.

RESULTS

Of 123 patients included in the final analysis, 66 (54%) received statin therapy during the study period. No difference was observed in the primary outcome between the statin and control groups (RR: 1.73; 95% CI: 0.75-3.98; p=0.20). Multivariable Cox regression revealed that older age and higher baseline creatinine were associated with an increased risk of GIB within 1-year of CF-LVAD implantation.

CONCLUSION

Among patients with CF-LVADs, there was no significant difference in the incidence of major GIB events associated with the use of statin therapy. Further studies are needed to assess whether a true association exists.

Inhibition of angiogenesis in the management of refractory gastrointestinal bleeding in patients with LVAD support

BACKGROUND

Gastrointestinal bleeding (GIB) in patients with continuous flow left ventricular assist devices (CF-LVADs) is often related to GI angiodysplasia (GIAD). We previously reported data on VEGF inhibition with IV bevacizumab in the treatment of LVAD-associated GIAD bleeding, and now present follow-up data on patients treated with IV bevacizumab and/or low-dose oral pazopanib.

METHODS

All consecutive adult patients with LVAD-associated GIB from GIAD treated with bevacizumab or pazopanib, from July 20, 2017 to June 22, 2022, were included in the analysis. Data on hospitalizations, GI endoscopic procedures, and blood transfusions were obtained from first admission for GIB up to a median of 35.7 months following treatment initiation (range 1.3-59.8 months).

RESULTS

Eleven patients (91% male, mean 69.5 ± 8.9 years) were included. Eight patients (73%) received IV bevacizumab, two patients (18%) received oral pazopanib, and one patient (9%) received bevacizumab followed by pazopanib therapy. We observed a significantly decreased number of annualized hospitalizations for GIB (median difference - 2.87, p = 0.002), blood transfusions (median difference - 20.9, p = 0.01), and endoscopies (median difference - 6.95, p = 0.007) in patients pre- and post-anti-angiogenic therapy (bevacizumab and/or pazopanib). Similarly, a significant improvement in these clinical outcomes was noted in the bevacizumab group with decreased annualized hospitalizations (median difference - 2.75, p = 0.014), blood transfusions (median difference - 24.5, p = 0.047), and number of endoscopies (median differences -6.88, p = 0.006).

CONCLUSION

Anti-angiogenic therapy with IV bevacizumab and/or low-dose oral pazopanib appears to provide benefits in patients with LVAD-associated GIB with reduced hospitalizations, blood transfusions, and need for GI endoscopic procedures.

The Relation Between Viscous Energy Dissipation and Pulsation for Aortic Hemodynamics Driven by a Left Ventricular Assist Device

Left ventricular assist device (LVAD) provides mechanical circulatory support for patients with advanced heart failure. Treatment using LVAD is commonly associated with complications such as stroke and gastro-intestinal bleeding. These complications are intimately related to the state of hemodynamics in the aorta, driven by a jet flow from the LVAD outflow graft that impinges into the aorta wall. Here we conduct a systematic analyses of hemodynamics driven by an LVAD with a specific focus on viscous energy transport and dissipation. We conduct a complementary set of analysis using idealized cylindrical tubes with diameter equivalent to common carotid artery and aorta, and a patient-specific model of 27 different LVAD configurations. Results from our analysis demonstrate how energy dissipation is governed by key parameters such as frequency and pulsation, wall elasticity, and LVAD outflow graft surgical anastomosis. We find that frequency, pulsation, and surgical angles have a dominant effect, while wall elasticity has a weaker effect, in determining the state of energy dissipation. For the patient-specific scenario, we also find that energy dissipation is higher in the aortic arch and lower in the abdominal aorta, when compared to the baseline flow without an LVAD. This further illustrates the key hemodynamic role played by the LVAD outflow jet impingement, and subsequent aortic hemodynamics during LVAD operation.

HFSA Expert Consensus Statement on the Medical Management of Patients on Durable Mechanical Circulatory Support

The medical management of patients supported with durable continuous flow left ventricular assist device (LVAD) support encompasses pharmacologic therapies administered in the preoperative, intraoperative, postoperative and chronic LVAD support stages. As patients live longer on LVAD support, the risks of LVAD-related complications and progression of cardiovascular and other diseases increase. Using existing data from cohort studies, registries, randomized trials and expert opinion, this Heart Failure Society of America Consensus Document on the Medical Management of Patients on Durable Mechanical Circulatory Support offers best practices on the management of patients on durable MCS, focusing on pharmacological therapies administered to patients on continuous flow LVADs. While quality data in the LVAD population are few, the utilization of guideline directed heart failure medical therapies (GDMT) and the importance of blood pressure management, right ventricular preload and afterload optimization, and antiplatelet and anticoagulation regimens are discussed. Recommended pharmacologic regimens used to mitigate or treat common complications encountered during LVAD support, including arrhythmias, vasoplegia, mucocutaneous bleeding, and infectious complications are addressed. Finally, this document touches on important potential pharmacological interactions from anti-depressants, herbal and nutritional supplements of relevance to providers of patients on LVAD support.

Quantitative Assessment of Aortic Hemodynamics for Varying Left Ventricular Assist Device Outflow Graft Angles and Flow Pulsation

Left ventricular assist devices (LVADs) comprise a primary treatment choice for advanced heart failure patients. Treatment with LVAD is commonly associated with complications like stroke and gastro-intestinal (GI) bleeding, which adversely impacts treatment outcomes, and causes fatalities. The etiology and mechanisms of these complications can be linked to the fact that LVAD outflow jet leads to an altered state of hemodynamics in the aorta as compared to baseline flow driven by aortic jet during ventricular systole. Here, we present a framework for quantitative assessment of aortic hemodynamics in LVAD flows realistic human vasculature, with a focus on quantifying the differences between flow driven by LVAD jet and the physiological aortic jet when no LVAD is present. We model hemodynamics in the aortic arch proximal to the LVAD outflow graft, as well as in the abdominal aorta away from the LVAD region. We characterize hemodynamics using quantitative descriptors of flow velocity, stasis, helicity, vorticity and mixing, and wall shear stress. These are used on a set of 27 LVAD scenarios obtained by parametrically varying LVAD outflow graft anastomosis angles, and LVAD flow pulse modulation. Computed descriptors for each of these scenarios are compared against the baseline flow, and a detailed quantitative characterization of the altered state of hemodynamics due to LVAD operation (when compared to baseline aortic flow) is compiled. These are interpreted using a conceptual model for LVAD flow that distinguishes between flow originating from the LVAD outflow jet (and its impingement on the aorta wall), and flow originating from aortic jet during aortic valve opening in normal physiological state.

Gastrointestinal bleeding in patients with continuous-flow left ventricular assist devices: A comprehensive review

BACKGROUND

Gastrointestinal bleeding is a major cause of morbidity that plagues the quality of life of patients supported on contemporary continuous-flow left ventricular assist devices (CF-LVADs). Despite benefits in survival and the nearly 50% reduction in complications provided by CF-LVADs, bleeding remains one of the most frequent adverse events with CF-LVAD implants. The CF-LVADs cause an increased risk of bleeding mainly due to the activation of the coagulation cascade.

METHODS

A literature search was done using PubMed and Google Scholar from Inception to February 2022. Qualitative analyses of the articles retrieved were used to construct this review. This review attempts to provide a comprehensive summary of the epidemiology, pathophysiology, risk stratification, and management of gastrointestinal bleeding as a complication of CF-LVAD as well as propose an algorithm for diagnosis and treatment.

RESULTS

Bleeding can occur at different sites in the gastrointestinal tract, the most common underlying pathology being arteriovenous malformations located in the upper gastrointestinal tract The increased prevalence of gastrointestinal (GI) bleeding in CF-LVAD patients has been attributed to the physiology of the LVAD itself, the use of anticoagulants, as well as patient comorbidities. Management involves pharmacologic and nonpharmacologic strategies.

CONCLUSIONS

CF-LVAD-supported patients have a significant risk of GI bleeding that is mainly caused by arteriovenous malformations located in the upper GI tract. The increased prevalence of GI bleeding in CF-LVAD patients is attributed to several etiologies that include factors attributed to the device itself and extrinsic factors such as the use of anticoagulation.

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.

A Multicenter Study of Left Ventricular Assist Device-Related Gastrointestinal Bleeding

INTRODUCTION

Continuous left ventricular assist devices (LVADs) offer hemodynamic support in advanced and decompensated heart failure but are often complicated by gastrointestinal bleeding (GIB) in medically fragile patients.

METHODS

We performed a retrospective analysis of 475 consecutive patients who underwent LVAD implantation at the Massachusetts General Hospital and Tufts Medical Center from 2008 to 2019 and identified 128 patients with clinically significant GIB. Clinical characteristics of each bleeding event, including procedures and interventions, were recorded. We examined LVAD patients with overt and occult presentations to determine diagnostic endoscopic yield and analyzed predictors of recurrent GIB.

RESULTS

We identified 128 unique patients with LVAD implantation complicated by GIB. No significant difference was observed based on study center, underlying cardiomyopathy, race/ethnicity, serum indices, and medications used. Overt bleeders presented more commonly during LVAD implantation admission ( P = 0.001) than occult bleeders. Occult bleed presentations had only 1 lower and no middle GI bleed source identified, despite similar workups to overt bleeds. Destination therapy (e.g., among nontransplant candidates) LVAD implantation (odds ratio 2.38, 95% confidence interval 1.05-5.58) and a history of GIB (odds ratio 3.85, 95% confidence interval 1.29-12.7) were independently associated with an increased risk of recurrent GIB-related hospitalization.

DISCUSSION

Our findings confirm a high rate of GIB, especially in destination LVAD patients, and show a low diagnostic yield for colonoscopy and middle GI bleed assessments in LVAD patients with occult bleeds. Overt bleeding was more common and associated with vascular malformations. Although endoscopic interventions stopped active hemorrhage, GIB often recurred.

Retrospective Review of Secondary Prevention Strategies for Gastrointestinal Bleeding and Associated Clinical Outcomes in Left Ventricular Assist Device Patients

BACKGROUND

Gastrointestinal bleeding (GIB) is one of the most common bleeding complications associated with Left Ventricular Assist Devices (LVAD). Currently, there is no strong evidence or clear guidance for which secondary GIB prophylaxis strategy should be implemented after the discontinuation of aspirin.

METHODS

Our single-center study describes the outcomes of 26 LVAD patients who experienced a total of 49 GIB events, these individuals were either in Group-1) lower INR target range or Group-2) lower INR target plus a hemostatic agent as the secondary prophylaxis strategy. Each GIB event was considered an independent event. Outcomes assessed were bleeding reoccurrence rates, time to next GIB, acute GIB strategies, GIB-free days, thromboembolic events, survival, coagulation, and hematologic parameters.

RESULTS

GIB reoccurrence rates were not statistically different, Group-1) 9 (40.9%) vs Group-2) 15 (55.6%), p = 0.308. Danazol was utilized 81.5% of the time as the designated hemostatic agent. Additionally, no significant differences were observed with all of our secondary outcome measures for bleeding, ischemic events, or survival.

CONCLUSION

While our study was not powered to assess the clinical outcomes related to survival and thromboembolic events, no discernable increased risk of ischemic events including pump thrombosis was observed. Our data suggest that a lower INR target range plus danazol does not confer any additional benefit over a lower INR target range only approach. The results of this report are hypothesis-generating and additional studies are warranted to elucidate the optimal antithrombotic strategy and role of hemostatic agents in reducing the risk of recurrent GIB events.

An external validation study of the Utah Bleeding Risk Score

OBJECTIVES

Gastrointestinal bleeding in patients with continuous-flow left ventricular assist devices (CF-LVAD) impairs quality of life and increases hospitalization rate. The Utah Bleeding Risk Score (UBRS) has been created to predict gastrointestinal bleeding (GIB) in patients on left ventricular assist device. We here aimed to externally validate UBRS on our cohort of CF-LVAD patients.

METHODS

Utah Bleeding Risk Score was calculated, GIB events summarized on follow-up and patients stratified into 3 risk groups. Predictive ability of UBRS was examined at 3 years and during whole support time and person time incidence rates correlated to UBRS. In a sub-analysis, single effects of UBRS variables on freedom from GIB were assessed.

RESULTS

A total of 111 CF-LVAD patients were included. The median UBRS was 2 (3-1). Receiver operating characteristic curve analysis showed an area under the curve of 0.519 (P = 0.758, 95% confidence interval = 0.422-0.615) at 3 years and an area under the curve of 0.515 (P = 0.797, 95% confidence interval = 0.418-0.611) during whole support time. No significant difference was observed in UBRS between bleeders and non-bleeders (P = 0.80). No significant difference in freedom from GIB was observed (P3 years = 0.7; Psupport-time = 0.816) and no independent significance regarding the freedom from bleeding at 3 years for any variable was observed. Coronary artery disease was associated with higher risk of GIB beyond the 3rd year (P = 0.048).

CONCLUSIONS

UBRS was not able to predict GIB and therefore not applicable in our cohort of patients. Coronary artery disease could lead to a higher risk for GIB during support time. An additional validation in a larger cohort is advisable.

Clinical considerations for the evaluation of patients with left ventricular assist devices

ABSTRACT

A left ventricular assist device (LVAD) provides mechanical circulatory support for patients with end-stage heart failure. As these devices become more prevalent, clinicians must be familiar with the device's function, common complications, and management strategies when evaluating this patient population.

Left Ventricular Assist Device: Indication, Timing, and Management

Left ventricular assist devices (LVADs) are indicated in inotrope-dependent heart failure (HF) patients with pure or predominant LV dysfunction. Survival benefit is less clear in ambulatory, advanced HF. Timing is crucial: early, unnecessary exposure to the risks of surgery, and device-related complications (infections, stroke, and bleeding) should be weighed against the probability of dying or developing irreversible right ventricular and/or end-organ dysfunction while deferring implant. The interplay between LVAD and heart transplantation depends largely on donor availability and allocation rules. Postoperatively, quality of life depends on patients' expectations and is influenced by complications. Patients' preferences, prognosis, and alternative options-including palliation-should be openly discussed and reviewed before and after the operation.

Initial endoscopic intervention is not associated with reduced risk of recurrent gastrointestinal bleeding in left ventricular assist device patients

Background

Left ventricular assist devices (LVADs) are increasingly used for mechanical support of end-stage heart failure. Gastrointestinal bleeding (GIB) confers a significant morbidity in LVAD patients, with rates of up to 30% at 5 years. We assessed predictors of index and recurrent GIB (rGIB) in LVAD patients to risk stratify patients and evaluate if endoscopic approach and intervention at index GIB impacted rGIB.

Methods

A retrospective chart review of all LVAD patients at our institution from 01/01/2006 to 31/10/2016 was completed. Predictors for index and recurrent GIB were analyzed. Multivariate logistic regression analysis was created using only statistically significant dependent variables and adjusted for demographic variables.

Results

A total of 77/214 (36%) patients developed GIB, and 38/214 (17.8%) developed rGIB. Destination therapy (P=0.01), longer duration of LVAD (P=0.03), and low albumin (<3.5 g/dL) (P<0.001) were associated with increased risk of index GIB. Charlson Comorbidity Index, heart failure etiology, and Medicare were predictors of index GIB on univariate analysis, but this was not seen on multivariate analysis. Performing an endoscopy with/without intervention, non- angioectasia lesions, and location of bleeding were not statistically significant predictors of rGIB. Longer duration of hospitalization appeared to be protective for rGIB on univariate analysis.

Conclusions

Index endoscopy and intervention is not associated with reduced risk of rGIB in LVAD patients. Several independent factors are associated with the risk of index GIB. Albumin is a potentially modifiable risk factor, and likely contributes to bleeding through poor nutrition. It is a surrogate marker for systemic illness, and may have pharmacologic implications.

Successful use of long-acting octreotide for protracted gastrointestinal bleeding related to protein-losing enteropathy after the Fontan procedure: a case report

Gastrointestinal bleeding complicated with protein-losing enteropathy after the Fontan procedure has been often reported in recent years, but there is no established therapy for it.We report the case of an 18-year-old boy who suffered from abdominal pain, melena, and anaemia due to intractable haemorrhagic protein-losing enteropathy after the Fontan procedure. He was successfully treated with octreotide therapy.

Role of Video Capsule in Small Bowel Bleeding

Video capsule endoscopy has an essential role in the diagnosis and management of small bowel bleeding and is the first-line study recommended for this purpose. This article reviews the risk factors for small bowel bleeding, optimal timing for video capsule endoscopy testing, and algorithms recommended for evaluation. Used primarily for the assessment of nonacute gastrointestinal blood loss, video capsule endoscopy has an emerging role for more urgent use in emergency settings and in special populations. Future software incorporation of neural networks to enhance lesion detection will likely result in an augmented role of video capsule endoscopy in small bowel bleeding.

How I treat gastrointestinal bleeding in congenital and acquired von Willebrand disease

Gastrointestinal (GI) bleeding is distinctive of severe von Willebrand disease (VWD), generally arising in older patients; in most cases, blood transfusion and hospitalization are required. The presence of arteriovenous malformations is often described when endoscopic examinations are performed. Patients with congenital type 3, 2A, and 2B are those most frequently affected by this symptom, possibly due to the loss of high-molecular-weight multimers of von Willebrand factor (VWF). GI bleeding can also occur in patients affected by acquired von Willebrand syndrome. Endoscopic examination of the GI tract is necessary to exclude ulcers and polyps or cancer as possible causes of GI bleeding. In congenital VWD, prophylaxis with VWF/factor VIII concentrates is generally started after GI-bleeding events, but this therapy is not always successful. Iron supplementation must be prescribed to avoid chronic iron deficiency. Possible rescue therapies (high-dose statins, octreotide, thalidomide, lenalidomide, and tamoxifen) were described in a few case reports and series; however, surgery may be necessary in emergency situations or if medical treatment fails to stop bleeding. In this article, we present several clinical cases that highlight the clinical challenges of these patients and possible strategies for their long-term management.

Left Ventricular Assist Device-Related Complications

Left ventricular assist device (LVAD) has emerged as a safe, durable, and revolutionary therapy for end-stage heart failure patients. Despite the appearance of newer-generation devices that have improved patient outcomes, the burden of adverse events remains significant. Although the survival rate for patients with LVAD is appreciated to be 81% at 1 year and 70% at 2 years, the incidence of adverse events is also high. Over time, both early and late postimplant complications have diminished in terms of prevalence and impact; however, complications, such as infections, bleeding, right heart failure, pump thrombosis, aortic insufficiency, or stroke, continue to represent a challenge for the practitioner. Therefore, the aim of this review is to highlight the most recent data regarding the current use of LVAD in the treatment of end-stage heart failure, with a specific focus on LVAD-related complications, in order to improve device-related outcomes. It will also revise how to mitigate the risk and how to approach specific adverse events. Withal, understanding the predisposing risk factors associated with postimplant complications, early recognition and appropriate treatment help to significantly improve the prognosis for patients with end-stage heart failure.

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.

Cardiac Emergencies in Patients with Left Ventricular Assist Devices

Continuous-flow left ventricular assist devices are frequently used for management of patients with advanced heart failure with reduced ejection fraction. Although technologic advancements have contributed to improved outcomes, several complications arise over time. These complications result from several factors, including medication effects, physiologic responses to chronic exposure to circulatory support that is minimally/entirely nonpulsatile, and dysfunction of the device itself. Clinical presentation can range from chronic and indolent to acute, life-threatening emergencies. Several areas of uncertainty exist regarding best practices for managing complications; however, growing awareness has led to development of new guidelines to reduce risk and improve outcomes.

Treatment of gastrointestinal bleeding in left ventricular assist devices: A comprehensive review

Left ventricular assist devices (LVAD) are increasingly become common as life prolonging therapy in patients with advanced heart failure. Current devices are now used as definitive treatment in some patients given the improved durability of continuous flow pumps. Unfortunately, continuous flow LVADs are fraught with complications such as gastrointestinal (GI) bleeding that are primarily attributed to the formation of arteriovenous malformations. With frequent GI bleeding, antiplatelet and anticoagulation therapies are usually discontinued increasing the risk of life-threatening events. Small bowel bleeds account for 15% as the source and patients often undergo multiple endoscopic procedures. Treatment strategies include resuscitative measures and endoscopic therapies. Medical treatment is with octreotide. Novel treatment options include thalidomide, angiotensin converting enzyme inhibitors/angiotensin II receptor blockers, estrogen-based hormonal therapies, doxycycline, desmopressin and bevacizumab. Current research has explored the mechanism of frequent GI bleeds in this population, including destruction of von Willebrand factor, upregulation of tissue factor, vascular endothelial growth factor, tumor necrosis factor-α, tumor growth factor-β, and angiopoetin-2, and downregulation of angiopoetin-1. In addition, healthcare resource utilization is only increasing in this patient population with higher admissions, readmissions, blood product utilization, and endoscopy. While some of the novel endoscopic and medical therapies for LVAD bleeds are still in their development stages, these tools will yet be crucial as the number of LVAD placements will likely only increase in the coming years.

Acquired Von Willebrand Syndrome (AVWS) in cardiovascular disease: a state of the art review for clinicians

Von Willebrand Factor (vWF) is a large glycoprotein with a broad range of physiological and pathological functions in health and disease. While vWF is critical for normal hemostasis, vascular integrity and repair, quantitative and qualitative abnormalities in the molecule can predispose to serious bleeding and thrombosis. The heritable form of von Willebrand Disease was first described nearly a century ago, but more recently, recognition of an acquired condition known as acquired von Willebrand Syndrome (AVWF) has emerged in persons with hematological, endocrine and cardiovascular diseases, disorders and conditions. An in-depth understanding of the causes, diagnostic approach and management of AVWS is important for practicing clinicians.

Bleeding in critical care associated with left ventricular assist devices: pathophysiology, symptoms, and management

Chronic heart failure (HF) is a growing health problem, and it is associated with high morbidity and mortality. Left ventricular assist devices (LVADs) are nowadays an important treatment option for patients with end-stage HF not only as a bridging tool to heart transplantation but also, as a permanent therapy for end-stage HF (destination therapy). The use of LVAD is associated with a high risk for bleeding complications and thromboembolic events, including pump thrombosis and ischemic stroke. Bleeding is the most frequent complication, occurring in 30% to 60% of patients, both early and late after LVAD implantation. Although the design of LVADs has improved over time, bleeding complications are still the most common complication and occur very frequently. The introduction of an LVAD results in an altered hemostatic balance as a consequence of blood-pump interactions, changes in hemodynamics, acquired coagulation abnormalities, and the strict need for long-term anticoagulant treatment with oral anticoagulants and antiplatelet therapy. LVAD patients may experience an acquired coagulopathy, including platelet dysfunction and impaired von Willebrand factor activity, resulting in acquired von Willebrand syndrome. In this educational manuscript, the epidemiology, etiology, and pathophysiology of bleeding in patients with LVAD will be discussed. Because hematologist are frequently consulted in cases of bleeding problems in these individuals in a critical care setting, the observed type of bleeding complications and management strategies to treat bleeding are also reviewed.

Approach to Complications of Ventricular Assist Devices: A Clinical Review for the Emergency Provider

BACKGROUND

Heart failure is a major public health problem in the United States. Increasingly, patients with advanced heart failure that fail medical therapy are being treated with implanted ventricular assist devices (VADs).

OBJECTIVE

This review provides an evidence-based summary of the current data for the evaluation and management of implanted VAD complications in an emergency department context.

DISCUSSION

With a prevalence of >5.8 million individuals and >550,000 new cases diagnosed each year, heart failure is a major public health problem in the United States. Increasingly, patients with advanced heart failure that fail medical therapy are being treated with implanted VADs. As the prevalence of patients with VADs continues to grow, they will sporadically present to the emergency department, regardless of whether the facility is a designated VAD center. As a result, all emergency physicians must be familiar with the basic principles of VAD function, as well as the diagnosis and initial management of VAD-related complications. In this review, we address these topics, with a focus on contemporary third-generation continuous flow VADs. This review will help supplement the critical care skills of emergency physicians in managing this complex patient population.

CONCLUSIONS

The cornerstone of managing the unstable VAD patient is rapid initiation of high-quality supportive care and recognition of device-related complications, as well as the identification and use of specialist VAD teams and other resources for support. Emergency physicians must understand VADs so that they may optimally manage these complex patients.