Proposal for Updated Nomenclature and Classification of Potential Causative Mechanism in Patent Foramen Ovale-Associated Stroke.

Importance: Recent epidemiologic and therapeutic advances have transformed understanding of the role of and therapeutic approach to patent foramen ovale (PFO) in ischemic stroke. Patent foramen ovale is likely responsible for approximately 5% of all ischemic strokes and 10% of those occurring in young and middle-aged adults. Observations: Randomized clinical trials have demonstrated that, to prevent recurrent ischemic stroke in patients with PFO and an otherwise-cryptogenic index ischemic stroke, PFO closure is superior to antiplatelet medical therapy alone; these trials have provided some evidence that, among medical therapy options, anticoagulants may be more effective than antiplatelet agents. Conclusions and Relevance: These new data indicate a need to update classification schemes of causative mechanisms in stroke, developed in an era in which an association between PFO and stroke was viewed as uncertain. We propose a revised general nomenclature and classification framework for PFO-associated stroke and detailed revisions for the 3 major stroke subtyping algorithms in wide use.

Revascularization strategies for patients with myocardial infarction and multi-vessel disease: A critical appraisal of the current evidence.

Approximately half of patients presenting with myocardial infarction are found to have non-infarct related multi-vessel severe coronary artery disease. Various observational studies and randomized controlled trials have been conducted to assess if revascularization of non-infarct related artery is associated with better clinical outcomes. In this review, the authors discuss the various revascularization strategies in patients with multi-vessel disease who present with myocardial infarction.

Patent Foramen Ovale and Hypoxemia.

Patent foramen ovale (PFO), an embryonic remnant of the fetal circulation, is present in 20-25% of adults. Although recent observational studies and clinical trials have established the link between PFO-mediated right-to-left shunting with cryptogenic stroke and migraine with aura, the role of a PFO in exacerbating hypoxemic medical conditions (ie, sleep apnea, chronic obstructive pulmonary disease, pulmonary hypertension, platypnea-orthodeoxia, pulmonary arteriovenous malformation, high-altitude pulmonary edema, and exercise desaturation) remains less understood. PFO-mediated hypoxemia occurs when deoxygenated venous blood from the right atrium enters and mixes with oxygenated arterial blood in the left atrium. Patients with an intracardiac right-to-left shunt may have profound hypoxemia out of proportion to underlying primary lung disease, even in the presence of normal right-sided pressures. The presence of right-to-left cardiac shunting can exacerbate the degree of hypoxemia in patients with underlying pulmonary disorders. In a subset of these patients, percutaneous PFO closure may result in marked improvement in dyspnea and hypoxemia. This review discusses the association between PFO-mediated right-to-left shunting with medical conditions associated with hypoxemia and explores the role of percutaneous PFO closure in alleviating the hypoxemia.

Cryptogenic Stroke and Patent Foramen Ovale.

Nearly one-half of patients with cryptogenic stroke have a patent foramen ovale (PFO). The dilemma of whether to close these PFOs percutaneously, in an effort to reduce the risk of recurrent paradoxical embolism, has been a matter of ongoing debate for more than a decade. Early randomized clinical trials failed to demonstrate a significant benefit of percutaneous PFO closure for secondary prevention of cryptogenic stroke in an intention-to-treat analysis. The long-term follow-up data from the RESPECT trial and 2 new randomized trials (CLOSE and REDUCE) have clarified these findings. They showed that with good patient selection, transcatheter PFO closure significantly reduces the risk of recurrent stroke compared with medical therapy in patients with cryptogenic stroke, with no increased risk of serious adverse events or influence on major bleeding.