Vascular inflammation and abnormal aortic histomorphometry in patients after pulsatile- and continuous-flow left ventricular assist device placement

Abstract

Background: Left ventricular assist devices are increasingly being used in patients with advanced heart failure as both destination therapy and bridge to transplant. We aimed to identify histomorphometric, structural and inflammatory changes after pulsatile- and continuous-flow left ventricular assist device placement.

Methods: Clinical and echocardiographic data were collected from medical records. Aortic wall diameter, cellularity and inflammation were assessed by immunohistochemistry on aortic tissue collected at left ventricular assist device placement and at explantation during heart transplantation. Expression of adhesion molecules was quantified by Western blot.

Results: Decellularization of the aortic tunica media was observed in patients receiving continuous-flow support. Both device types showed an increased inflammatory response after left ventricular assist device placement with variable T-cell and macrophage accumulations and increased expression of vascular E-selectin, ICAM and VCAM in the aortic wall.

Conclusions: Left ventricular assist device implantation is associated with distinct vascular derangements with development of vascular inflammation. These changes are pronounced in patients on continuous-flow left ventricular assist and associated with aortic media decellularization. The present findings help to explain the progressive aortic root dilation and vascular dysfunction in patients after continuous-flow device placement.

Keywords: adhesion molecule; aorta; heart failure; histology; inflammation; left ventricular assist device.