Brief history of patent foramen ovale and stroke.

Abstract

Lechat is usually credited with first calling attention to patent foramen ovale (PFO) and stroke in 1988.1 Previous studies of the role of echocardiography in stroke rarely, if ever, mentioned PFO and focused on now-almost-forgotten disorders, such as mitral valve prolapse.2 Interest in PFO has emerged for 3 main reasons: (1) renewed interest in cryptogenic stroke especially in younger patients; (2) technical advances, including bubble contrast transthoracic echocardiography, transesophageal echocardiography, and saline contrast transcranial doppler; and (3) perhaps most importantly, the emergence of endovascular device closure as a treatment option. Cryptogenic stroke is highly prevalent in stroke populations under the age of 55 years. Many of these patients have circumstantial evidence for embolism on MR, such as cortical infarct location or multiple silent infarcts in different vascular territories. Large PFO with a substantial shunt and atrial septal aneurysm has been identified in many (although not all) studies as anatomic comorbidities associated with stroke. However, as with PFO detection, new technology, including implantable cardiac monitors and MR plaque morphological analysis, has identified occult atrial fibrillation and acute rupture of benign atherosclerotic plaques as underdiagnosed causes of crytpogenic stroke.3 This suggests that in many patients with cryptogenic stroke, a PFO may be coincidental. The explosion of device technology has played a central role in the PFO renaissance. Reimbursement policies and an inherent bias in young patients with stroke to close the hole bolstered by numerous observational case series provided a strong incentive for endovascular device closure.4 With this background, 3 randomized clinical trials of the management of patients with cryptogenic stroke and PFO have recently been completed. Given the lingering controversy, it is important to review why the Evaluation of the STARFlex Septal Closure System in Patients With a Stroke and/or Transient Ischemic Attack Due to Presumed Paradoxical …