Inflow Valve Regurgitation During Left Ventricular Assist Device Support May Interfere With Reverse Ventricular Remodeling

Background. Left ventricular assist devices have been reported previously to reverse ventricular remodeling in patients with dilated cardiomyopathy. In patients with prolonged mechanical support, structural failure of the left ventricular assist device inflow valve can cause regurgitation into the left ventricle, which may affect adversely this process. Methods. Left ventricular end-diastolic pressure–volume relation of hearts explanted from 8 patients with left ventricular assist device and 8 control subjects with idiopathic cardiomyopathy was determined ex vivo at the time of transplantation. Results. Duration of mechanical support ranged from 210 to 276 days (mean ± standard deviation = 283 ± 76 days) in 3 patients with inflow valve regurgitation versus 100 to 155 days (132 ± 22 days) in 5 patients without (p = 0.005). The end-diastolic pressure–volume relation of all hearts supported mechanically was shifted to the left toward normal controls. This effect was markedly attenuated in patients with inflow valve regurgitation. Conclusions. Mechanical assistance can cause reverse remodeling in patients with dilated cardiomyopathy as evidenced by the shift in the end-diastolic pressure–volume relation curve to the left. Inflow valve failure, associated with prolonged support, can attenuate changes in left ventricular structure and dimension. Ineffective pressure and volume unloading may explain these observations.