Association between angiotensin II antagonism and gastrointestinal bleeding on left ventricular assist device support

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.

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.

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

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

Impact of renin-angiotensin-aldosterone system inhibition on morbidity and mortality during long-term continuous-flow left ventricular assist device support: An IMACS report

BACKGROUND

Inhibition of the renin angiotensin aldosterone system (RAAS) improves survival and reduces adverse cardiac events in heart failure with reduced ejection fraction, but the benefit is not well-defined following left ventricular assist device (LVAD).

METHODS

We analyzed the ISHLT IMACS registry for adults with a primary, continuous-flow LVAD from January 2013 to September 2017 who were alive at postoperative month 3 without a major adverse event, and categorized patients according to treatment an angiotensin converting enzyme inhibitor (ACEI/ARB) or mineralocorticoid receptor antagonist (MRA). Propensity score matching was performed separately for ACEI/ARB vs none (n = 4,118 each) and MRA vs none (n = 3,892 each).

RESULTS

Of 11,494 patients included, 50% were treated with ACEI/ARB and 38% with MRA. Kaplan-Meier survival was significantly better for patients receiving ACEI/ARB (p < 0.001) but not MRA (p = 0.31). In Cox proportional hazards analyses adjusted for known predictors of mortality following LVAD, ACEI/ARB use (hazard ratio 0.81 [95% confidence interval 0.71-0.93], p < 0.0001) but not MRA use (hazard ratio 1.03 [95% confidence interval 0.88-1.21], p = 0.69) was independently associated with lower mortality. Among patients treated with an ACEI/ARB, there was a significantly lower unadjusted risk of cardiovascular death (p < 0.001), risk of gastrointestinal bleeding (p = 0.01), and creatinine level (p < 0.001). MRA therapy was associated with lower risk of gastrointestinal bleeding (p = 0.01) but higher risk of hemolysis (p < 0.01). Potential limitations include residual confounding and therapy crossover.

CONCLUSION

These findings suggest a benefit for ACEI/ARB therapy in patients with heart failure after LVAD implantation.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

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

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

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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