Endoscopic evaluation and management of gastrointestinal bleeding in patients with ventricular assist devices. Gastroenterol Res Pract. 2012;2012:630483. [PMID: 22474445 PMCID: PMC3299279 DOI: 10.1155/2012/630483]

Pre- and Post-Implant Endoscopy in Left Ventricular Assist Device Recipients: A Single-Center Experience

Background

Gastrointestinal bleeding (GIB) is common in left ventricular assist devices (LVADs) patients, but the optimal screening approach before LVAD implantation is still unclear. The aim of the study was to describe our experience with pre- and post-LVAD implantation endoscopic screening and subsequent GI bleeding in this cohort.

Methods

A retrospective review was conducted among all patients who underwent LVAD implantation at Saint Luke's Hospital, between 2010 and 2020. The data were reviewed to determine the yield and safety of endoscopic procedures performed within 1 month before LVAD placement and the incidence of GIB within 1 year after implantation.

Results

A total of 167 LVAD patients met the inclusion criteria, and 23 underwent pre-implantation endoscopic evaluation. Angiodysplasia had a significantly higher odds ratio (OR) of 9.41 (95% confidence interval (CI): 2.01 - 44.09) in post-LVAD endoscopy, while there was no significant difference in bleeding from other sources such as peptic ulcer disease or diverticular bleeding. There was no difference in the incidence of GIB in patients who underwent endoscopic evaluation pre-LVAD compared to post-LVAD GIB (32.6% vs. 39.1%, P = 0.64). Endoscopy was well-tolerated in this cohort, and argon plasma coagulation was the most commonly used intervention to achieve hemostasis.

Conclusions

According to our results, we recommend against routine pre-LVAD endoscopic screening. Instead, we suggest an individualized approach, where decisions are made on a case-by-case basis.

Partial Pressure of End-Tidal Oxygen and Blood Lactate During Cardiopulmonary Exercise Testing in Healthy Older Participants and Patients at Risk of Cardiac Disease

Background

The partial pressure of end-tidal oxygen (PETO2) and end-tidal oxygen concentration (ETO2) are among the indices that can be measured by exhaled gas analysis. Several observational studies have shown that skeletal muscle function is impaired in patients with cardiac disease; thus, the assessment of skeletal muscle function is important. Additionally, although it has recently been suggested that the difference in PETO2 from rest to the ventilatory anaerobic threshold (VAT) reflects oxygen availability in peripheral factors, primarily skeletal muscle, the evidence for this is not well established. Therefore, we hypothesized and investigated whether increased blood lactate (BLa) levels, resulting from decreased skeletal muscle and mitochondrial oxygen availability, and PETO2 dynamics during cardiopulmonary exercise testing (CPET) would be related.

Methods

All participants performed the symptomatic limited CPET, and their BLa levels were measured. The difference in PETO2 and ETO2 from rest to VAT determined by the V-slope method (ΔPETO2 and ΔETO2) was calculated and compared with the increase in BLa due to exercise testing.

Results

We recruited 22 healthy older participants (nine males; 69.4 ± 6.8 years) and 11 patients with cardiovascular risk (eight males; 73.0 ± 8.8 years). ΔPETO2 and ΔETO2 did not differ between the two groups (P = 0.355 and P = 0.369, respectively), showing no correlation between increase in BLa from rest to VAT, but were significantly correlated with an increase in BLa from rest to the end of exercise (ΔPETO2, P = 0.030; ΔETO2, P = 0.029). The correlation was particularly pronounced among those at cardiovascular risk (ΔPETO2, P = 0.012; ΔETO2, P = 0.011).

Conclusions

ΔPETO2 and ΔETO2 from rest to VAT during CPET may be useful as indices reflecting skeletal muscle oxygen utilization capacity.

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.

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.

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.

Gastrointestinal Bleeding Following LVAD Placement from Top to Bottom

BACKGROUND

Left ventricular assist devices (LVADs) are an increasingly prevalent form of mechanical support for patients with end-stage heart failure. These devices can be implanted both as a bridge to transplant and as definitive/destination therapy. Gastrointestinal (GI) bleeding is one of the most common and recalcitrant long-term complications following LVAD implantation, with an incidence approaching 30 %.

AIMS

This review will discuss what is known about the pathophysiology of GI bleeding in LVADs and the currently available options for medical and/or endoscopic management.

RESULTS

The pathophysiology of bleeding is multifactorial, with hemodynamic alterations, acquired von Willebrand factor deficiency, and coagulopathy being most often implicated. The majority of bleeding events in this population result from angioectasias and gastroduodenal erosive disease. While these bleeding events are significant and often require transfusion therapy, they are rarely life threatening. Endoscopy remains the standard of care with upper endoscopy offering the highest diagnostic yield in these patients. However, the effectiveness of endoscopic hemostasis in this population is not well established. A small number of studies have evaluated medical therapy and alterations in LVAD settings as a means of preventing or treating bleeding with variable results.

CONCLUSIONS

In summary, GI bleeding with LVADs is a common occurrence and will continue to be as more LVADs are being performed for destination therapy.

Video capsule endoscopy in left ventricular assist device recipients with obscure gastrointestinal bleeding

AIM: To assess whether video capsule endoscopy (VCE) affects the outcomes of left ventricular assist devices (LVADs) recipients with gastrointestinal bleeding.

METHODS: This is a retrospective study of LVAD recipients with obscure gastrointestinal bleeding (OGIB) who underwent VCE at a tertiary medical center between 2005 and 2013. All patients were admitted and monitored with telemetry and all VCE and subsequent endoscopic procedures were performed as inpatients. A VCE study was considered positive only when P2 lesions were found and was regarded as negative if P1 or P0 were identified. All patients were followed until heart transplant, death, or the end of the study.

RESULTS: Between 2005 and 2013, 30 patients with LVAD underwent VCE. Completion rate of VCE was 93.3% and there was no capsule retention. No interference of VCE recording or the function of LVAD was found. VCE was positive in 40% of patients (n = 12). The most common finding was active small intestinal bleeding (50%) and small intestinal angiodysplasia (33.3%). There was no difference in the rate of recurrent bleeding between patients with positive and negative VCE study (50.0% vs 55.6%, P = 1.00) during an average of 11.6 ± 9.6 mo follow up. Among patients with positive VCE, the recurrent bleeding rate did not differ whether subsequent endoscopy was performed (50% vs 50%, P = 1.00).

CONCLUSION: VCE can be safely performed in LVAD recipients with a diagnostic yield of 40%. VCE does not affect recurrent bleeding in LVAD patients regardless of findings.

Radionuclide small intestine imaging

The aim of this overview article is to present the current possibilities of radionuclide scintigraphic small intestine imaging. Nuclear medicine has a few methods-scintigraphy with red blood cells labelled by means of (99m)Tc for detection of the source of bleeding in the small intestine, Meckel's diverticulum scintigraphy for detection of the ectopic gastric mucosa, radionuclide somatostatin receptor imaging for carcinoid, and radionuclide inflammation imaging. Video capsule or deep enteroscopy is the method of choice for detection of most lesions in the small intestine. Small intestine scintigraphies are only a complementary imaging method and can be successful, for example, for the detection of the bleeding site in the small intestine, ectopic gastric mucosa, carcinoid and its metastasis, or inflammation. Radionuclide scintigraphic small intestine imaging is an effective imaging modality in the localisation of small intestine lesions for patients in whom other diagnostic tests have failed to locate any lesions or are not available.