Abstract 1765: Fusion of the Aortic Valve Commissures During Continuous Axial Flow Left Ventricular Assist Device Support
Introduction: An association between aortic valve fusion and the use of pulsatile left ventricular assist devices (LVAD) has been previously described. This has been attributed to diminished flow across the aortic valve during ventricular systole reducing leaflet excursion and increasing duration of leaflet coaptation. We describe fusion of aortic valve (AoV) commissures in seven patients who were bridged to transplant with a new, continuous axial flow LVAD.
Methods: Explanted hearts from seven patients supported by the HeartMate II LVAD were examined for degree of AoV thickening and number of commissures involved. Echocardiograms were retrospectively reviewed for the presence or absence of aortic insufficiency (AI) and AoV opening before and after LVAD placement.
Results: Six of seven explanted hearts were found to have AoV commissural fusion. Of these six hearts, 3 were male and 3 female with an average age of 38±19 years. Two patients had ischemic cardiomyopathy and diabetes with the remaining having nonischemic cardiomyopathy only. Average duration of mechanical support for hearts with AoV fusion was 383 days (range 33–730 days). One heart had fusion of two commissures and the remaining five had fusion of one commissure. AoV commissural fusion was graded as mild in 3 and moderate in 3 hearts. Five echocardiograms of the fused AoV hearts were available for review pre implantation and all had evidence of valve opening with 80% having AI. One month after LVAD placement the AoV opened in three of six hearts with AI present in five. Six months post implant one of five patients with AoV fusion had AoV opening and all had AI. Accurate assessment of AI and AoV opening was limited by the number of cardiac cycles captured on routine echocardiography.
Conclusions: Varying degrees of aortic valve commissural fusion were present in six of seven patients supported with a continuous axial flow LVAD after as little as 33 days. Aortic insufficiency was present in the majority of hearts at one and six months with a corresponding decreasing incidence of AoV opening. Given the interest in possibly weaning patients from LVADs, it may be important to set the flow speed to allow for routine aortic valve opening to prevent AoV commissural fusion.