Higher soluble thrombomodulin and angiogenic markers in continuous flow left ventricular assist device-supported patients associated with arteriovenous malformation and nonsurgical bleeding.

Bleeding complications are a bane of continuous flow left ventricular assist devices (cfLVAD); gastrointestinal bleeding (GIB) from arteriovenous malformation (AVM) predominating. We hypothesized that shear stress disrupts vascular endothelium altering angiogenesis and contributing to bleeding. We profiled markers of endothelial dysfunction (soluble thrombomodulin [sTM]) and angiogenesis (angiopoietin-1 [Ang-1], angiopoietin-2 [Ang-2]) in 21 patients implanted with a centrifugal cfLVAD. Bleeding episodes were documented in 11 patients, 8 had GIB, 4 of whom had AVMs. We observed a dynamic change in sTM and Ang-2/Ang-1 ratio following cfLVAD support (p = 0.030 and p = 0.025, respectively). Bleeding patients had higher sTM and Ang-2/Ang-1 ratios than patients with no bleeding (p = 0.04 and p = 0.06, respectively). At D180, patients with AVMs had significantly higher Ang-2/Ang-1 ratios vs patients without proven AVMs (p = 0.006). We conclude that bleeding in cfLVAD-supported patients is associated with alteration in endothelial/vascular homeostasis, possibly contributing to AVM formation.