Acquired commissural fusion of aortic valves in patients with left ventricular assist devices

Background: Left ventricular assist devices (LVADs) currently are used as bridges for patients who deteriorate clinically while awaiting cardiac transplantation. At the time of transplantation or subsequent death, we can assess the effect of long-term device implantation on cardiac structural changes. We have noted, in our years of experience, that aortic valve commissures may fuse in patients supported by LVADs. These observations may be important in the use of these pumps as long-term destination therapy. Methods: We examined 33 hearts (both explants and autopsy specimens) from patients supported either with vented-electric (VE) HeartMates (n = 21) or with implantable pneumatic HeartMates (n = 12). We noted commissures involved, fusion length (mm), duration of LVAD support, and type of LVAD. As controls, we examined 49 explanted hearts from patients with heart failure who were not supported by LVADs. Results: We found commissural fusion in 17 of the 33 hearts. Of those 17 hearts, 4 (23.5%) had 2 commissural fusions, and 13 (76.5%) had only 1 fusion. Fusion length ranged from 5 mm to 17 mm (mean, 9.9 mm). The lesion was more common in patients fitted with VE HeartMates (p < 0.0002). We found small amounts of commissural fusion in 8 of the 49 control hearts. Conclusions: Acquired commissural fusion is common in patients supported by LVADs, particularly the VE HeartMate. The lesion also occurs occasionally in failing hearts of patients not supported by LVADs. The significance of the lesion in patients who require long-term LVAD support either as a bridge to transplantation or as destination therapy is unclear.