Multicenter Evaluation of Octreotide as Secondary Prophylaxis in Patients With Left Ventricular Assist Devices and Gastrointestinal Bleeding

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.

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.

Thrombotic and Hemorrhagic Complications Following Left Ventricular Assist Device Placement: An Emphasis on Gastrointestinal Bleeding, Stroke, and Pump Thrombosis

The left ventricular assist device (LVAD) is a mechanical circulatory support device that supports the heart failure patient as a bridge to transplant (BTT) or as a destination therapy for those who have other medical comorbidities or complications that disqualify them from meeting transplant criteria. In patients with severe heart failure, LVAD use has extended survival and improved signs and symptoms of cardiac congestion and low cardiac output, such as dyspnea, fatigue, and exercise intolerance. However, these devices are associated with specific hematologic and thrombotic complications. In this manuscript, we review the common hematologic complications of LVADs.

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 in recipients of left ventricular assist devices-a systematic review

The twenty-first century has revolutionized the management of congestive heart failure with the widespread use of left ventricular assist devices and other treatment modalities that improve morbidity and mortality after the failure of medical management. These novel devices come with significant side effects. One of the most common side effects of left ventricular assist devices is the increased frequency of lower gastrointestinal bleeding compared to heart failure patients without left ventricular assist devices. Multiple etiologies of recurrent gastrointestinal bleeding in such patients have been studied. The decreased amount of von Willebrand factor polymers is now recognized as one of the most common causes of increased incidence of gastrointestinal bleeding in patients with left ventricular assist devices alongside increased arteriovenous malformations. Multiple treatment modalities have been identified to prevent and treat gastrointestinal bleeding in these patients. Since the use of left ventricular assist devices is becoming more prevalent in patients with advanced heart failure, we decided to conduct this systematic review. The article summarizes the incidence, pathophysiology, and management of lower gastrointestinal bleeding in patients with left ventricular assist devices.

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.

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.

Gastrointestinal bleeding during the transcatheter aortic valve replacement perioperative period: A Review

With the aging of the population, the incidence of senile degenerative valvular heart disease is expected to increase. Transcatheter aortic valve replacement (TAVR) has been used for patients at lower surgical risk with symptomatic severe aortic valve stenosis. Because of the improvements in TAVR technology and increasing experience of the operators, TAVR is regarded as a safe and feasible procedure. Bleeding events during the TAVR perioperative period, especially gastrointestinal (GI) bleeding, have been proven to be related to the long-term prognosis and mortality. Elderly patients with valvular heart disease are susceptible to GI bleeding because of their use of antithrombotic drugs, physical damage of coagulation factors, and GI angiodysplasia. Frequent GI bleeding and low levels of preoperative hemoglobin increase the risk of TAVR, especially for elderly patients. Because of these risks, which are easily overlooked, we should focus more attention on the perioperative management of TAVR. Reasonable screening tools, including blood examinations, risk evaluation scales, and endoscopy, are beneficial to the prevention of complications that can occur during the perioperative period. Additionally, medical therapy can safely help patients at high-risk for bleeding patients throughout the perioperative period. This study aimed to characterize the pathology of TAVR patients and discuss treatment strategies for GI bleeding during the perioperative period.

Antithrombotic therapy for durable left ventricular assist devices - current strategies and future directions

Left ventricular assist devices (LVADs) improve survival and quality of life for patients with advanced heart failure but are associated with high rates of thromboembolic and hemorrhagic complications. Antithrombotic therapy is required following LVAD implantation, though practices vary. Identifying a therapeutic strategy that minimizes the risks of thromboembolic and hemorrhagic complications is critical to optimizing patient outcomes and is an area of active investigation. This paper reviews strategies for initiating and maintaining antithrombotic therapy in durable LVAD recipients, focusing on those with centrifugal-flow devices.

Prevalence, management, and outcomes of haemorrhagic events in left ventricular assist device recipients

AIMS

Left ventricular assist devices (LVADs) have reduced the mortality of patients with advanced heart failure both as bridge-to-transplant and as destination therapy. However, LVADs are associated with various complications, including bleedings, which affect the prognosis. The aim of the study was to explore the prevalence, management, and outcomes of haemorrhagic adverse events in LVAD recipients.

METHODS AND RESULTS

We conducted a retrospective, single-centre, cohort study including all patients who received an LVAD from January 2008 to December 2019 in our tertiary centre (Rangueil University Hospital, Toulouse, France). Bleeding events, death, and heart transplantation were collected from electronic medical files. Eighty-eight patients were included, and 43 (49%) presented at least one bleeding event. Gastrointestinal (GI) bleeding was the most frequent (n = 21, 24%), followed by epistaxis (n = 12, 14%) and intracranial haemorrhage (n = 9, 10%). Bleeding events were associated with increased mortality [hazard ratio (HR) 3.8, 95% confidence interval (CI) 1.5-9.3, P < 0.01], particularly in case of intracranial haemorrhage (HR 14.6, 95% CI 4.2-51.1, P < 0.0001). GI bleedings were associated with a trend towards increased mortality (HR 3.0, 95% CI 0.9-9.3, P = 0.05). Each bleeding episode multiplied the risk of death by 1.8 (95% CI 1.2-2.7, P < 0.01). Finally, only early bleedings (<9 months post-implantation) had an impact on mortality (HR 4.2, 95% CI 1.6-11.1, P < 0.01). Therapeutic management was mainly based on temporary interruption of anticoagulation and permanent interruption of antiplatelet therapy. Invasive management was rarely performed.

CONCLUSIONS

Haemorrhagic events in LVAD recipients are frequent and associated with increased mortality. GI bleedings are the most frequent, and intracranial haemorrhages the most associated with mortality. Management remains empirical requiring more research.

Gastrointestinal Bleeding Rates in Left Ventricular Assist Device Population Reduced with Octreotide Utilization

Patients with continuous-flow left ventricular assist devices have a high risk of gastrointestinal bleeding (GIB) and recurrent bleeding. Studies have shown octreotide can reduce the risk of GIB. This retrospective, case-crossover study, evaluated the efficacy of octreotide for the prevention of recurrent GIB in patients with left ventricular assist devices between August 2008 and October 2018. A total of 32 patients received octreotide and were included in the study. Hospital admission for GIB was evaluated before and after the initiation of octreotide. Each case served as his/her own control. Most patients were on a reduced aspirin dose (56.2%) and had a reduced international normalized ratio goal (59.4%) before starting monthly octreotide. The most common dose of long-acting octreotide was 30 mg every 28 days. Overall, octreotide decreased the frequency of GIB (4.3 vs. 0.9 events/year, p < 0.001). Nineteen (59.4%) patients did not have a subsequent gastrointestinal bleed. Of the 13 patients who rebled after initiation of octreotide, the frequency of events decreased by 2.6 bleeds per patient per year (4.8 vs. 2.2; p = 0.043). In high-risk patients who have failed conventional therapy, octreotide can be useful for the prevention of recurrent GIB.

Acquired von Willebrand Syndrome

Acquired von Willebrand syndrome can occur in the setting of myeloproliferative neoplasms; plasma cell dyscrasias and other lymphoproliferative disorders; autoimmune conditions; and causes of increased shear forces, such as aortic stenosis or other structural heart disease and mechanical circulatory support. The depletion of von Willebrand factor, especially high-molecular-weight multimers, can lead to mucocutaneous bleeding and the formation of arteriovenous malformations, particularly in the gastrointestinal tract. Management focuses on correction of the underlying cause when possible, but may include intravenous immunoglobulins, von Willebrand factor concentrate, rituximab, or antiangiogenic therapy depending on the clinical context.

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.

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.

Thalidomide Use Reduces Risk of Refractory Gastrointestinal Bleeding in Patients with Continuous Flow Left Ventricular Assist Devices

Gastrointestinal (GI) bleeding is a common complication seen in patients with implanted continuous flow left ventricular assist devices (CF-LVAD), often attributed to arteriovenous malformations (AVMs). Whether thalidomide reduces recurrent GI bleeding risk in CF-LVAD patients has been incompletely evaluated. We conducted a retrospective review of all CF-LVAD patients at our institution with GI bleeding from AVMs who had a trial both off and on thalidomide. The primary endpoint was time to rebleed, while secondary endpoints included overall GI bleeding events, packed red blood cell (PRBC) transfusion requirements, and adverse events related to thalidomide. We report on 24 patients with recurrent AVM-associated GI bleeding who met criteria for and received thalidomide therapy, of which 17 had sufficient follow-up to be ultimately included for final analysis. We found the risk of rebleeding was significantly reduced in those on thalidomide therapy versus off (hazard ratio = 0.23, p = 0.022). The median number of GI bleeds per year was reduced from 4.6 to 0.4 (p = 0.0008) and the PRBC requirement was lower (36.1 vs. 0.9 units per year, p = 0.004) in those on thalidomide therapy. The adverse event rate with thalidomide was 59%, with symptoms resolution in most following dose reduction without increased bleeding. Thalidomide reduced the risk of AVM-associated GI rebleeding, number of bleeding events, and PRBC requirements in CF-LVAD patients. When initiating therapy, potential side effects and overall clinical context should be considered.

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.

Plasma Somatostatin in Advanced Heart Failure: Association with Cardiac Filling Pressures and Outcome

BACKGROUND

Somatostatin inhibits intestinal motility and hormonal secretion and is a potent arterial vasoconstrictor of the splanchnic blood flow. It is unknown if somatostatin concentrations are associated with central hemodynamic measurements in patients with advanced heart failure (HF).

METHODS

A prospective study of HF patients with a left ventricular ejection fraction (LVEF) <45% referred to right heart catheterization (RHC) for evaluation for heart transplantation (HTX) or left ventricular assist device (LVAD).

RESULTS

Fifty-three patients were included with mean LVEF 18 ± 8% and majority in NYHA-class III-IV (79%). Median plasma somatostatin concentration was 18 pmol/L. In univariable regression analysis, log(somatostatin) was associated with increased central venous pressure (CVP; r2 = 0.14, p = 0.003) and a reduced cardiac index (CI; r2 = 0.15, p = 0.004). When adjusted for selected clinical variables (age, gender, LVEF, eGFR and BMI), log(somatostatin) remained a significant predictor of CVP (p = 0.044). Increased somatostatin concentrations predicted mortality in multivariable models (hazard ratio: 5.2 [1.2-22.2], p = 0.026) but not the combined endpoint of death, LVAD implantation or HTX.

CONCLUSIONS

Somatostatin concentrations were associated with CVP and CI in patients with HF. The pathophysiological mechanism may be related to congestion and/or hypoperfusion of the intestine. Somatostatin was an independent predictor of mortality in advanced HF.

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.

The Predicament of Gastrointestinal Bleeding in Patients With a Continuous-Flow Left Ventricular Assist Device: Pathophysiology, Evaluation, and Management

Heart failure affects over 5 million Americans, with numbers expected to rise. While heart transplantation is the most effective long-term strategy for end-stage heart failure, there is a limited cardiac donor pool, and these organs are often unavailable at the time of need. Left ventricular assist devices, therefore, continue to be used to bridge this gap. Originally implanted as a bridge to transplant, these devices are now additionally utilized as destination therapy for patients ineligible for transplant. With the widespread applicability of these devices for not just temporary measures, but also for prolonged use, the short- and long-term impact on other organ systems has become more evident. For example, gastrointestinal (GI) bleeding, with an incidence approaching 30%, is one such complication post-continuous-flow left ventricular assist device implantation. This high incidence of GI bleeding is thought to stem from a combination of factors, including the need for concomitant anticoagulant and antiplatelet therapy, and intrinsic device-related properties resulting in acquired Von Willebrand disease and arteriovenous malformations. Due to the significant morbidity associated with these GI bleeding events, a standardized protocol optimizing medical and endoscopic management, alongside close coordination between the gastroenterology and cardiology services, should be advocated for and ultimately employed.

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.

Omega-3 Therapy Is Associated With Reduced Gastrointestinal Bleeding in Patients With Continuous-Flow Left Ventricular Assist Device

Background Gastrointestinal bleeding (GIB) is a common complication seen in patients supported with left ventricular assist devices (LVADs) and is related to increased inflammation and angiogenesis. Omega-3 is an unsaturated fatty acid that possesses anti-inflammatory and antiangiogenic properties. This study aims to assess the prophylactic efficacy of treatment with omega-3 on the incidence of GIB in LVAD patients. Methods and Results Among consecutive 166 LVAD patients enrolled in this analysis, 30 patients (49 years old and 26 male) received 4 mg/d of omega-3 therapy for 310±87 days and 136 patients in the control group (58 years old and 98 male) were observed for 302±102 days. One-year GIB-free rate was significantly higher in the omega-3 group as compared with the control group (97% versus 73%; P=0.02). Omega-3 therapy was associated with the occurrence of GIB in both the univariate (hazard ratio, 0.12; 95% CI, 0.02-0.91; P=0.040) and multivariate Cox proportional hazard ratio analyses (hazard ratio, 0.13; 95% CI, 0.02-0.98; P=0.047). The frequency of GIB was significantly lower in the omega-3 group (0.08±0.42 versus 0.37±0.93 events/y; P=0.01), accompanied by significantly lower blood product transfusion and shorter days in the hospital. The frequency of GIB remained lower among the omega-3 group after matching for patient background characteristics (96% versus 73%, P=0.028). Conclusions LVAD patients treated with omega-3 had a significant increase in freedom from GIB. A randomized controlled study is warranted to evaluate the use of omega-3 in LVAD patients.

Experience of the use of octreotide for refractory gastrointestinal bleeding in a patient with Jarvik2000® left ventricular assist device

Gastrointestinal bleeding (GIB) is among the major complications affecting implantable continuous-flow left ventricular assist device (iLVAD) recipients and is the major cause of re-hospitalization. GIB in iLVAD recipients is sometimes critical, and controlling bleeding using conventional approaches is difficult. A 35-year-old woman developed refractory GIB from multiple gastric polyps and de novo angiodysplasia after Jarvik2000^® iLVAD implantation. Discontinuation of anticoagulation and antiplatelet therapies had little effect on GIB; thus, multiple endoscopic hemostatic therapies were performed. However, bleeding recurred several times, and red blood cell (RBC) transfusion in large volumes was required for progressive anemia. Furthermore, the von Willebrand factor (VWF) multimer analysis revealed loss of the high-molecular weight multimer, which may have resulted from the high-speed rotation of the axial-flow LVAD pump. To supplement VWF, cryoprecipitate was administered, but it was effective for only several days. Finally, the patient was treated with octreotide, a somatostatin analog, on post-operative day 58. After starting octreotide, tarry stool gradually decreased, and progression of anemia slowed down within the first 14 days of treatment; thus, the total RBC transfusion volume was reduced without additional hemostatic interventions, including cryoprecipitate administration. The patient developed mediastinitis on post-operative day 68 and died of sepsis on post-operative day 72. There was no adverse effect associated with octreotide use. Although the observation period was short, octreotide appears to be useful for resolving recurrent GIB after iLVAD implantation and reducing blood transfusions.

Arteriovenous malformations respond poorly to argon plasma coagulation in patients with continuous flow left ventricular assist devices

BACKGROUND

Gastrointestinal bleeding in patients with continuous flow left ventricular assist devices (LVADs) causes significant morbidity. Arteriovenous malformations (AVMs) cause 30-60% of bleeds, yet the efficacy of endoscopic interventions and risk factors for rebleeding have not been studied.

PATIENTS AND METHODS

The charts of all LVAD patients undergoing endoscopy for gastrointestinal bleeding at Stanford between January 2010 and December 2017 were reviewed. Cox proportional hazard modeling was used to evaluate risk factors for rebleeding, including the type of endoscopic treatment, patient characteristics, and endoscopic findings.

RESULTS

Of 54 total LVAD patients presenting with gastrointestinal bleeding, 23 (42.6%) had AVMs documented on endoscopy. Treatment with argon plasma coagulation (APC) alone was associated with a higher risk of rebleeding compared to no treatment [hazard ratio (HR)=4.77, P=0.012], and compared with clip±APC (HR=7.47, P=0.012). The 90-day bleed-free rate was 10.9% with APC, 100% with clipping±APC, and 83.3% with no endoscopic treatment. Additional risk factors for rebleeding included the presence of gastric AVMs (HR=3.64, P=0.024), and presence of hematochezia (HR=5.15, P=0.05). In a multiple Cox regression model, only the presence of gastric AVMs (HR=5.50, P=0.029) and APC use (HR=14.3, P=0.008) remained significant predictors of rebleeding.

CONCLUSION

The use of APC alone for the treatment of AVMs in LVAD patients had a high failure rate. The presence of gastric AVMs was a significant risk factor for rebleeding in LVAD patients. Management decisions should take these factors into account.

Left ventricular assist devices and their complications: A review for emergency clinicians

INTRODUCTION

End stage heart failure is associated with high mortality. However, recent developments such as the ventricular assist device (VAD) have improved patient outcomes, with left ventricular assist devices (LVAD) most commonly implanted.

OBJECTIVE

This narrative review evaluates LVAD epidemiology, indications, normal function and components, and the assessment and management of complications in the emergency department (ED).

DISCUSSION

The LVAD is a life-saving device in patients with severe heart failure. While first generation devices provided pulsatile flow, current LVAD devices produce continuous flow. Normal components include the pump, inflow and outflow cannulas, driveline, and external controller. Complications related to the LVAD can be divided into those that are LVAD-specific and LVAD-associated, and many of these complications can result in severe patient morbidity and mortality. LVAD-specific complications include device malfunction/failure, pump thrombosis, and suction event, while LVAD-associated complications include bleeding, cerebrovascular event, infection, right ventricular failure, dysrhythmia, and aortic regurgitation. Assessment of LVAD function, patient perfusion, and mean arterial pressure is needed upon presentation. Electrocardiogram and bedside ultrasound are key evaluations in the ED. LVAD evaluation and management require a team-based approach, and consultation with the LVAD specialist is recommended.

CONCLUSION

Emergency clinician knowledge of LVAD function, components, and complications is integral in optimizing care of these patients.

Acquired von Willebrand Syndrome in Patients With Ventricular Assist Device

During the last decade the use of ventricular assist devices (VADs) for patients with severe heart failure has increased tremendously. However, flow disturbances, mainly high shear induced by the device is associated with bleeding complications. Shear stress-induced changes in VWF conformation are associated with a loss of high molecular weight multimers (HMW) of VWF and an increased risk of bleeding. This phenomenon and its cause will be elaborated and reviewed in the following.

Omega-3 Therapy Is Associated With Reduced Gastrointestinal Bleeding in Patients With Continuous-Flow Left Ventricular Assist Device

Background Gastrointestinal bleeding (GIB) is a common complication seen in patients supported with left ventricular assist devices (LVADs) and is related to increased inflammation and angiogenesis. Omega-3 is an unsaturated fatty acid that possesses anti-inflammatory and antiangiogenic properties. This study aims to assess the prophylactic efficacy of treatment with omega-3 on the incidence of GIB in LVAD patients. Methods and Results Among consecutive 166 LVAD patients enrolled in this analysis, 30 patients (49 years old and 26 male) received 4 mg/d of omega-3 therapy for 310±87 days and 136 patients in the control group (58 years old and 98 male) were observed for 302±102 days. One-year GIB-free rate was significantly higher in the omega-3 group as compared with the control group (97% versus 73%; P=0.02). Omega-3 therapy was associated with the occurrence of GIB in both the univariate (hazard ratio, 0.12; 95% CI, 0.02-0.91; P=0.040) and multivariate Cox proportional hazard ratio analyses (hazard ratio, 0.13; 95% CI, 0.02-0.98; P=0.047). The frequency of GIB was significantly lower in the omega-3 group (0.08±0.42 versus 0.37±0.93 events/y; P=0.01), accompanied by significantly lower blood product transfusion and shorter days in the hospital. The frequency of GIB remained lower among the omega-3 group after matching for patient background characteristics (96% versus 73%, P=0.028). Conclusions LVAD patients treated with omega-3 had a significant increase in freedom from GIB. A randomized controlled study is warranted to evaluate the use of omega-3 in LVAD patients.