Background: Long-term left ventricular assist device (LVAD) support diminishes flow through the native aortic valve and decreases valve motion. This may cause aortic valve commissural fusion. The clinical importance of such fusion is not well understood.
Methods: Thirty-three consecutive patients receiving long-term LVAD support were followed up until transplantation or death. In each case, the native aortic valve was examined pathologically for commissural fusion. Pathology findings were correlated with hemodynamic performance as assessed by both LVAD pump flow and echocardiography.
Results: Seventeen of the 33 patients had some degree of native aortic valve commissural fusion. Four patients had fusion at 2 commissures; of these, 2 had clinically significant native valve aortic insufficiency (2+ or greater), and 1 exhibited trace insufficiency of the native aortic valve. Thirteen patients had fusion at only 1 aortic commissure; of these, 2 had clinically significant aortic insufficiency (2+ or greater), and 3 had trace or mild (1+) insufficiency of native aortic valve. Two of the 4 patients with fusion at 2 commissures required increased LVAD support of >3 liters/min/cm2. No patient with fusion of only 1 commissure required increased LVAD support. Three patients with no commissural fusion of the aortic valve required increased LVAD support secondary to sepsis.
Conclusions: Commissural fusion of the native aortic valve occurs in a significant number of patients receiving long-term LVAD support and can necessitate increased levels of LVAD support. Recognition of this phenomenon may allow development of strategies to minimize commissural fusion and extend LVAD pump life.