Hemodynamic vertebrobasilar insufficiency as an adverse effect of antihypertensive therapy.

A 63-year-old white male with a 25-year history of hypertension experienced the onset of intermittent diplopia and gait disturbance 24 hours after a change in antihypertensive medication from atenolol 50 mg/d to enalapril 5 mg bid. Three weeks later, the patient was admitted with a worsening of symptoms. Cerebral arteriography revealed significant bilateral vertebral artery stenosis. Symptoms continued to progress in the hospital, and at the time of posterior circulation revascularization the patient had a persistent bilateral internuclear ophthalmoplegia and right ptosis. The need for a neurovascular workup and adjustment of therapy in patients with antihypertensive-associated cerebral ischemia is discussed.