Objective and importance: Treatment of one side in cases of dissecting aneurysms of the bilateral vertebral arteries (VAs) with subarachnoid hemorrhage may result in dissection or rupture on the contralateral side.
Clinical presentation: Three patients presented with dissecting aneurysms of the bilateral VAs with subarachnoid hemorrhage.
Intervention: Two patients underwent trapping of the ruptured VA, with side-to-side anastomosis between the bilateral posteroinferior cerebellar arteries. One patient underwent resection of the ruptured VA, with interposition of a saphenous vein graft. Two patients died as a result of rupture of the contralateral VA dissecting aneurysm after surgery. One patient demonstrated development of an unruptured dissecting aneurysm in the contralateral VA 1 month after surgery.
Conclusion: Surgical intervention to treat dissecting aneurysms of the bilateral VAs on one side carries the risk of rupture of the contralateral lesion. Increased hemodynamic stress may be important in the development and rupture of dissections in the contralateral VA.