American Heart Association

Clinical and In Vitro Evidence that LVAD-Induced Von Willebrand Factor Degradation May Alter Angiogenesis

Contributor: Darien Allen

GI bleeds in continuous-flow left ventricular assist device (CF-LVAD) patients are an increasing problem. Bartoli et al posit a two-hit hypothesis to explain the increased risk of mucosal bleeds in this population:

Hit 1: CF-LVAD-induced shear stress activates von Willebrand factor (VWF) multimers leading to enzymatic and mechanical degradation into variably sized fragments and acquired VWF deficiency. CF-LVAD induced VWF deficiency reduces VWF-collagen and VWF-platelet binding resulting in increased risk of mucosal bleeding.
Hit 2: Higher circulating concentrations of VWF fragments lead to altered angiogenesis and likely contribute to the development of angiodysplasia.

Octreotide may prevent recurrent GI bleeds in CF-LVAD patients

Contributor: Nick Hawkes

CF-LVAD patients experience high rates of gastrointestinal (GI) bleeding. A multicenter, retrospective analysis by Shah et al demonstrated that patients with a prior GI bleed after CF-LVAD implantation had a lower rate (24% vs 43%) of recurrent GI bleed when receiving octreotide.

Fifty-one patients were identified from 5 participating centers. All patients had one previous GI bleed following CF-LVAD implantation, and received octreotide treatment for at least 6 months following index GI bleed. Octreotide was dosed as a monthly depot injection in 72% of patients or twice daily subcutaneous injection in 28%. Shah et al used a comparison group of HMII CF-LVAD patients who had experienced a GI bleed in clinical trials using HMII bridge-to-transplant (BTT) and destination therapy (DT). Patients were propensity matched based on HF etiology, CF-LVAD indication, CF-LVAD support time, sex, and age. Of the 51 CF-LVAD patients analyzed, 50% were DT. Twelve patients (24%) who received octreotide experienced a recurrent bleed vs 22 (43%) of the comparison group (p<0.04).