Treatment Efficacy in Vertebrobasilar Transient Ischemic Attacks Presenting as Isolated Vertigo: A Retrospective Case Study

Background: Vertigo without other neurological symptoms is usually not supposed to be due to a vascular cause. However, hypoperfusion of the anterior cerebellar artery can lead to ischemia of the vestibular labyrinth and/or vestibular nuclei in the pontomedullary region whereas hypoperfusion of the posterior cerebellar artery can cause ischemia of the vestibulocerebellum, all resulting in isolated vertigo. Methods: We retrospectively reviewed the clinical records of patients with vertebrobasilar ischemic attacks referred to our outpatient dizziness clinic during the years 1999-2009. Patients who presented only with vertigo (+/– vomiting and unsteadiness) were selected. Their clinical data, findings and treatment responses were recorded. Results: Amongst about one hundred patients with vertebrobasilar TIA we found 24 patients with monosymptomatic presentation. Their mean age was 67.3 years, fifteen were men. In most of the patients the vertigo attacsk were multiple and lasted from minutes to hours. All but four patients had at least one vascular risk factor at the time of presentation, among them 13 had multiple vascular risk factors. Seven patients had evidence of chronic ischemic changes on brain CT or MRI. Aspirin (100 325 mg/die) was started in 15 patients. Three patients were started on clopidogrel (75 mg/die) because of aspirin intolerance and two patients on warfarin due to atrial fibrillation. In two patients who were treated with aspirin prior to their vertigo attack, clopidogrel or dipyridamol were added. The mean time period from first attack to treatment initiation was 5.2 months. The mean follow up period was 27.4 months. In 18 patients the attacks have completely resolved after treatment initiation. Three patients had further vertigo attacks despite treatment. Two patients with vertigo episodes where a vascular etiology was not suspected, developed later an ischemic stroke in the vertebrobasilar territory (anterior cerebellar artery and vertebral artery infarct). Conclusions: The differential diagnosis of a vertigo attack presenting in a monosymptomatic form should include vertebrobasilar TIA, especially in individuals with vascular risk factors. In view of lack of a specific test for establishing the diagnosis antiplatelets should be administered on empirical grounds since early administration of therapy can abolish further attacks and prevent a vertebrobasilar stroke. Warfarin should be preserved for patients with cardiac conditions that warrant antiocoagulation for stroke prevention.