Characterization of Enteric Vasculopathy in Patients with Left Ventricular Assist Device (LVAD) Therapy: A Retrospective Analysis
Anand Kanagasabapathy, Louis P Dehner. Washington University School of Medicine, St Louis, MO
Background: Left ventricular assist devices (LVADs) are an increasingly used option in the management of end-stage refractory cardiac failure. Newer continious-flow devices are associated with improved clinical outcomes. However, there is an increased incidence of gastrointestinal (GI) bleeding, as reported by several large scale studies. For instance, upto one-third of patients with the Heartmate II device are reported to have developed arteriovenous malformation/s of the GI tract. To date however, the histopathologic nature of these putative vascular malformations has not been characterized.
Design: We included patients who were autopsied in the past 5 years at our institution, following ante-mortem LVAD support, in whom reliable morphologic evaluation was possible. Cases were retrieved from the files of the department of Pathology using appropriate keyword searches. Clinical information, including type of ventricular assist device, duration of device function, history of GI bleeding were obtained. Routine H&E sections from the esophagus, stomach, small and large bowel were examined with special attention to vascular changes.
Results: 18 patients (out of a total of 22) who were autopsied after LVAD placement were included in the study. They were predominantly male (M:F - 5:1), with age ranging from 3-71 years (median=59 yrs). The most commonly used device was the Heartmate II. Duration of support (from device implantation to death) ranged from 0 to 1213 days (median=40 days). In 4 cases (22%), vascular changes of varied morphology were observed in the GI tract, ranging from dilated submucosal native vascular channels, mucosal hemorrhagic necrosis, congestive capillary vascular ectasia, to frank submucosal bleeding. Of these, two patients had clinically significant GI hemorrhage and in one, the cause of death was extensive colonic bleeding. In this patient, distinctly clustered submucosal vessels with focal thrombi were observed. No arteriovenous malformations were seen in any of the cases.
Conclusions: A signifcant proportion of patients (∼20%) showed gastrointestinal vascular pathologic findings. The congestive vasculopathy appears to involve recruitment of existing native vessels, with associated hemorrhage, rather than formation of arteriovenous malformations. Our data suggest that a more diverse range of enteric vascular changes than currently understood, occur in the setting of patients on LVAD support and contribute to morbidity or mortality.
Monday, March 4, 2013 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 2, Monday Morning