A 62-year-old woman is evaluated in the stroke unit for a 2-day history of difficulty speaking and right arm weakness. She has a history of hypertension and dyslipidemia and a 35-pack-year smoking history. Medications are lisinopril, atenolol, simvastatin, and aspirin.
On physical examination, blood pressure is 148/78 mm Hg, pulse rate is 84/min and regular, and respiration rate is 12/min. Other general medical examination findings are normal. Neurologic examination shows mild sensory aphasia and right arm drift.
An MRI of the brain shows an acute infarct in the left middle cerebral artery distribution that appears embolic. A magnetic resonance angiogram of the head and neck is normal. An electrocardiogram shows sinus rhythm and is normal. Telemetry performed over the next 3 days shows occasional premature ventricular complexes. A transesophageal echocardiogram shows no intracardiac thrombus, normal left atrial appendage velocities, and a patent foramen ovale with an atrial septal aneurysm. No evidence of deep venous thrombosis is found.
Which of the following is the most appropriate next step in management?
A Percutaneous patent foramen ovale closure
B Prolonged cardiac rhythm monitoring
C Surgical closure of the patent foramen ovale
Manage cryptogenic ischemic stroke.
This patient’s condition should be managed with prolonged cardiac rhythm monitoring. She has infarcts that appear embolic on an MRI and no evidence of proximal arterial disease. As such, her stroke is classified as a cryptogenic ischemic stroke. According to data from recent studies, up to 25% of patients with cryptogenic ischemic stroke have paroxysmal atrial fibrillation on prolonged cardiac monitoring. A diagnosis of atrial fibrillation would be the only reason for this patient to start warfarin for stroke prevention. The risk of recurrent stroke in patients with an otherwise isolated patent foramen ovale, with or without an atrial septal aneurysm, is low in most clinical trials.
Percutaneous or surgical closure of a patent foramen ovale has not been shown to reduce the risk of ischemic stroke in patients with an otherwise cryptogenic stroke. Patent foramen ovale, especially in combination with an atrial septal aneurysm, is associated with an increased risk of ischemic stroke in epidemiologic studies, but the optimal medical treatment remains unknown. Preliminary results from the CLOSURE I trial showed no significant difference in the risk of stroke recurrence in patients with cryptogenic stroke randomized to either the percutaneous patent foramen ovale closure arm or the best medical treatment arm.
Warfarin is an inappropriate treatment for this patient at this time, pending results of cardiac rhythm monitoring. No clinical trials, including a substudy of the Warfarin-Aspirin Recurrent Stroke Study (WARSS), have shown the superiority of warfarin compared with aspirin in the prevention of recurrent cryptogenic stroke, even in the presence of a patent foramen ovale.
- Tayal AH, Tian M, Kelly KM, et al. Atrial fibrillation detected by mobile cardiac outpatient telemetry in cryptogenic TIA or stroke. Neurology. 2008;71(21):1696-1701. PMID: 18815386