Sleep apnea syndrome and patent foramen ovale: a dangerous association in ischemic stroke?

Patent Foramen Ovale Closure for Nonstroke Indications

The patent foramen ovale (PFO) is a flap or tunnel-like communication in the atrial septum present in 20% to 34% of the adult population. In most cases, it is a benign finding and poses no health risk. However, some PFOs may provide a conduit for bloodborne materials, such as thrombi, vasoactive substances, or air to pass into the systemic circulation causing a paradoxical embolus. PFOs have been linked with several clinical disease states including cryptogenic stroke, migraine headache, platypnea-orthodeoxia, and decompression illness. Percutaneous PFO closure provides a practical solution to the problem of PFO in carefully selected populations. Recent randomized control trials have demonstrated that PFO closure in patients with cryptogenic stroke is associated with reduced rates of recurrent stroke compared with medical therapy. This translated into a dramatic increase in the number of PFO closure procedures worldwide, primarily for the indication of cryptogenic stroke, with high procedural success and low complication rates. However, there are no randomized clinical trials available to support PFO closure in other clinical conditions. This article reviews potential indications, existing data, and management approaches for PFO closure in disorders other than cryptogenic stroke.

Sleep and Stroke: New Updates on Epidemiology, Pathophysiology, Assessment, and Treatment

PURPOSE OF REVIEW

This review aims to discuss the most recent data on sleep disorders and stroke, highlighting relevant findings for the practicing neurologist or health providers who encounter patients with sleep disorders and stroke.

RECENT FINDINGS

Sleep apnea and abnormal sleep duration have the strongest association with stroke risk. Possible mechanisms include non-dipping of blood pressure during sleep, hypoxemia or reoxygenation leading to sympathetic activation, hypertension, atrial fibrillation and impaired cerebral hemodynamics. Treatment studies suggest that continuous positive airway pressure (CPAP) for sleep apnea could improve primary prevention of stroke, but data is equivocal for secondary prevention. However, CPAP could improve functional outcomes after stroke.

SUMMARY

Sleep disorders present an opportunity to improve stroke risk and functional outcomes. However, new strategies are needed to determine the patients at high-risk who would most likely benefit from targeted care. Novel methods for phenotyping sleep disorders could provide personalized stroke care to improve clinical outcomes and public health strategies.