Gastrointestinal angiodysplasia in heart failure and during CF LVAD support

The Impact of Acute Exercise on Hemostasis and Angiogenesis Mediators in Patients With Continuous-Flow Left Ventricular Assist Devices: A Prospective Observational Pilot Study

Impaired primary hemostasis and dysregulated angiogenesis, known as a two-hit hypothesis, are associated with gastrointestinal (GI) bleeding in patients with continuous-flow left ventricular assist devices (CF-LVADs). Exercise is known to influence hemostasis and angiogenesis in healthy individuals; however, little is known about the effect in patients with CF-LVADs. The objective of this prospective observational study was to determine whether acute exercise modulates two-hit hypothesis mediators associated with GI bleeding in patients with a CF-LVAD. Twenty-two patients with CF-LVADs performed acute exercise either on a cycle ergometer for approximately 10 minutes or on a treadmill for 30 minutes. Blood samples were taken pre- and post-exercise to analyze hemostatic and angiogenic biomarkers. Acute exercise resulted in an increased platelet count ( p < 0.00001) and platelet function (induced by adenosine diphosphate, p = 0.0087; TRAP-6, p = 0.0005; ristocetin, p = 0.0009). Additionally, high-molecular-weight vWF multimers ( p < 0.00001), vWF collagen-binding activity ( p = 0.0012), factor VIII ( p = 0.034), angiopoietin-1 ( p = 0.0026), and vascular endothelial growth factor ( p = 0.0041) all increased after acute exercise. This pilot work demonstrates that acute exercise modulated two-hit hypothesis mediators associated with GI bleeding in patients with CF-LVADs.

Contrast-enhanced computed tomography assisted diagnosis of bleeding caused by colonic angiodysplasia: A case report

RATIONALE

Angiodysplasia (AD) in the gastrointestinal tract is a degenerative vascular condition characterized by vascular dilation, tortuosity, and arteriovenous connections within the mucosal and submucosal layers. AD is a significant cause of lower gastrointestinal bleeding in the elderly, often presenting as chronic, intermittent hemorrhage. The research challenge lies in the potential for multiple and minute AD lesions to be missed during endoscopy, which may lead to post-hemostatic rebleeding.

PATIENT CONCERNS

An 82-year-old female with a history of coronary artery disease treated with aspirin, presenting with recurrent melena and anemia. The patient exhibited a suboptimal response to blood transfusions and octreotide therapy.

DIAGNOSIS

After excluding tumorous bleeding in the initial contrast-enhanced computed tomography (CECT), we suspect vascular bleeding as the most probable etiology.

INTERVENTIONS

The initial colonoscopy was unsuccessful due to the occurrence of ventricular tachycardia. Considering the patient's advanced age, cardiac dysfunction, and frailty, a repeat CECT were conducted during episodes of suspected active bleeding. Vascular dilatation within the colonic hepatic flexure wall was visualized during the venous phase, accompanied by contrast agent extravasation into the intestinal lumen. The subsequent urgent colonoscopy and pathological specimens from surgical resection supported the diagnosis of colonic AD.

OUTCOMES

After the surgery, the patient did not experience melena thereafter.

LESSONS

We highlight that CECT for diagnosing AD-related bleeding offers higher safety and convenience, potentially superior to digital subtraction angiography, particularly in critically ill elderly patients.

Gastrointestinal Angiodysplasia Resolution After Transcatheter Aortic Valve Implantation

Importance

Heyde syndrome is the cooccurrence of aortic stenosis and gastrointestinal bleeding secondary to vascular lesions, including angiodysplasias. Several studies have demonstrated cessation of gastrointestinal bleeding after transcatheter aortic valve implantation (TAVI), but the etiology and effects on vascular lesions are largely unknown.

Objective

To examine the associations of TAVI with gastrointestinal vascular lesions and identify factors associated with recovery among patients with iron deficiency anemia and severe aortic stenosis.

Design, Setting, and Participants

In this prospective, single-center cohort study, patients with iron deficiency anemia on the TAVI waiting list from September 2020 to February 2022 were assessed by capsule endoscopy. Those with vascular lesions were reassessed 6 months after TAVI. Endoscopic images were anonymized and evaluated by 2 independent researchers. Data were analyzed from September 2022 to August 2024.

Exposure

TAVI.

Main Outcomes and Measures

The primary outcome was the mean difference in the number of vascular lesions before vs after TAVI.

Results

A total of 24 patients (mean [SD] age, 77.4 [7.1] years; 18 [75.0%] male) underwent capsule endoscopy, and vascular lesions were present in 18 patients (75.0%). TAVI was performed in 15 of 18 patients with vascular lesions, of whom 11 agreed to a second capsule endoscopy. The mean (SD) number of vascular lesions across the gastrointestinal tract decreased from 6.4 (5.6) lesions before TAVI to 2.0 (2.1) lesions 6 months after TAVI (P = .04). The number of vascular lesions decreased in 9 of 11 patients (81.8%), including 6 patients (54.5%) who no longer had typical angiodysplasias. Resolution of angiodysplasias was less frequent in patients who had multiple valvular heart disease before TAVI (0 of 3 patients) vs those without multiple valvular heart disease (6 of 8 patients [75.0%]) and in patients with significant paravalvular leakage after TAVI (2 of 5 patients [40.0%]) vs those without significant leakage (4 of 6 patients [66.7%]).

Conclusions and Relevance

In this cohort study of 24 patients with iron deficiency anemia and severe aortic stenosis, angiodysplasias were present in 75.0% of patients. TAVI was associated with reduced size and number of angiodysplasias in these patients. These findings suggest that TAVI not only improves aortic stenosis but may also reduce gastrointestinal bleeding by resolving vascular lesions, offering a dual benefit for patients with Heyde syndrome.

Whole-body mass spectrometry imaging reveals the systemic metabolic disorder and catecholamines biosynthesis alteration on heart-gut axis in heart failure rat

INTRODUCTION

Heart failure (HF) is a systemic metabolic disorder disease, across multiorgan investigations advancing knowledge of progression and treatment of HF. Whole-body MSI provides spatiotemporal information of metabolites in multiorgan and is expected to be a potent tool to dig out the complex mechanism of HF.

OBJECTIVES

This study aimed at exploring the systemic metabolic disorder in multiorgan and catecholamines biosynthesis alteration on heart-gut axis after HF.

METHODS

Whole-body MSI was used to characterize metabolic disorder of the whole rat body after HF. An integrated method by MSI, LC-MS/MS and ELISA was utilized to analyze key metabolites and enzymes on heart, small intestine, cecum and colon tissues of rat. Gut microbiota dysbiosis was investigated by 16S rDNA sequencing and metagenomic sequencing. Validation experiments and in vitro experiments were performed to verify the effect of catecholamines biosynthesis alteration on heart-gut axis after HF.

RESULTS

Whole-body MSI exhibited varieties of metabolites alteration in multiple organs. Remarkably, catecholamine biosynthesis was significantly altered in the serum, heart and intestines of rats. Furthermore, catecholamines and tyrosine hydroxylase were obviously upregulated in heart and colon tissue. Turicibacter_sanguinis was relevant to catecholamines of heart and colon. Validation experiments demonstrated excessive norepinephrine induced cardio-intestinal injury, including significantly elevating the levels of BNP, pro-BNP, LPS, DAO, and increased the abundance of Turicibacter_sanguinis. These alterations could be reversed by metoprolol treatment blocking the effect of norepinephrine. Additionally, in vitro studies demonstrated that norepinephrine promoted the growth of Turicibacter_sanguinis and Turicibacter_sanguinis could import and metabolize norepinephrine. Collectively, excessive norepinephrine exerted bidirectional effects on cardio-intestinal function to participate in the progression of HF.

CONCLUSION

Our study provides a new approach to elucidate multiorgan metabolic disorder and proposes new insights into heart-gut axis in HF development.

Standard of Care Versus Octreotide in Angiodysplasia-Related Bleeding (the OCEAN Study): A Multicenter Randomized Controlled Trial

BACKGROUND & AIMS

Gastrointestinal angiodysplasias are vascular anomalies that may result in transfusion-dependent anemia despite endoscopic therapy. An individual patient data meta-analysis of cohort studies suggests that octreotide decreases rebleeding rates, but component studies possessed a high risk of bias. We investigated the efficacy of octreotide in reducing the transfusion requirements of patients with angiodysplasia-related anemia in a clinical trial setting.

METHODS

The study was designed as a multicenter, open-label, randomized controlled trial. Patients with angiodysplasia bleeding were required to have had at least 4 red blood cell (RBC) units or parental iron infusions, or both, in the year preceding randomization. Patients were allocated (1:1) to 40-mg octreotide long-acting release intramuscular every 28 days or standard of care, including endoscopic therapy. The treatment duration was 1 year. The primary outcome was the mean difference in the number of transfusion units (RBC + parental iron) between the octreotide and standard of care groups. Patients who received at least 1 octreotide injection or followed standard of care for at least 1 month were included in the intention-to-treat analyses. Analyses of covariance were used to adjust for baseline transfusion requirements and incomplete follow-up.

RESULTS

We enrolled 62 patients (mean age, 72 years; 32 men) from 17 Dutch hospitals in the octreotide (n = 31) and standard of care (n = 31) groups. Patients required a mean number of 20.3 (standard deviation, 15.6) transfusion units and 2.4 (standard deviation, 2.0) endoscopic procedures in the year before enrollment. The total number of transfusions was lower with octreotide (11.0; 95% confidence interval [CI], 5.5-16.5) compared with standard of care (21.2; 95% CI, 15.7-26.7). Octreotide reduced the mean number of transfusion units by 10.2 (95% CI, 2.4-18.1; P = .012). Octreotide reduced the annual volume of endoscopic procedures by 0.9 (95% CI, 0.3-1.5).

CONCLUSIONS

Octreotide effectively reduces transfusion requirements and the need for endoscopic therapy in patients with angiodysplasia-related anemia.

CLINICALTRIALS

gov, NCT02384122.

Intravenous administration of umbilical cord lining stem cells in left ventricular assist device recipients: Results of the uSTOP LVAD BLEED pilot study

Background

Left ventricular assist device (LVAD) implantation improves survival in advanced heart failure. Despite this, angiodysplastic bleeding complications remain a significant driver of costs as well as morbidity. Mechanisms implicated in post-LVAD implant bleeding include the dysregulation of angiogenic factors seen in this population. The present pilot study evaluates the safety of umbilical cord lining stem cells (ULSCs) in LVAD recipients while exploring any early evidence of efficacy to improve bleeding.

Methods

In a 3 + 3 design, 9 patients received an intravenous (IV) infusion of ULSCs at escalating doses. The primary endpoint was safety and tolerability, secondary exploratory outcomes included antibodies against hemoglobin to quantify the amount of blood in stool without the need for dietary restriction.

Results

The primary safety and tolerability outcomes were met as no infusion-related adverse events or toxic responses were observed. There was no sensitization after administration of ULSCs as assessed by panel reactive antibody. An increase in angiopoietin-1 levels and a decrease in angiopoietin-2 levels from baseline to 30 days were observed in 4 patients. Quantitative Faecal Immunochemical Test suggested a decrease in the mean blood content of stool from baseline to 30 days.

Conclusions

In this first-ever IV administration of ULSCs in LVAD patients, infusion was noted to be safe and tolerable and did not cause immune sensitization. Half of the patients were noted to have angiogenic stabilization, and there was a trend toward decreasing amounts of blood noted in the stool, suggesting an early signal of efficacy.

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.

Pulsatility and flow patterns across macro- and microcirculatory arteries of continuous-flow left ventricular assist device patients

BACKGROUND

Reduced arterial pulsatility in continuous-flow left ventricular assist devices (CF-LVAD) patients has been implicated in clinical complications. Consequently, recent improvements in clinical outcomes have been attributed to the "artificial pulse" technology inherent to the HeartMate3 (HM3) LVAD. However, the effect of the "artificial pulse" on arterial flow, transmission of pulsatility into the microcirculation and its association with LVAD pump parameters is not known.

METHODS

The local flow oscillation (pulsatility index, PI) of common carotid arteries (CCAs), middle cerebral arteries (MCAs) and central retinal arteries (CRAs-representing the microcirculation) were quantified by 2D-aligned, angle-corrected Doppler ultrasound in 148 participants: healthy controls, n = 32; heart failure (HF), n = 43; HeartMate II (HMII), n = 32; HM3, n = 41.

RESULTS

In HM3 patients, 2D-Doppler PI in beats with "artificial pulse" and beats with "continuous-flow" was similar to that of HMII patients across the macro- and microcirculation. Additionally, peak systolic velocity did not differ between HM3 and HMII patients. Transmission of PI into the microcirculation was higher in both HM3 (during the beats with "artificial pulse") and in HMII patients compared with HF patients. LVAD pump speed was inversely associated with microvascular PI in HMII and HM3 (HMII, r2 = 0.51, p < 0.0001; HM3 "continuous-flow," r2 = 0.32, p = 0.0009; HM3 "artificial pulse," r2 = 0.23, p = 0.007), while LVAD pump PI was only associated with microcirculatory PI in HMII patients.

CONCLUSIONS

The "artificial pulse" of the HM3 is detectable in the macro- and microcirculation but without creating a significant alteration in PI compared with HMII patients. Increased transmission of pulsatility and the association between pump speed and PI in the microcirculation indicate that the future clinical care of HM3 patients may involve individualized pump settings according to the microcirculatory PI in specific end-organs.