PFO and Cryptogenic Stroke: Finding Closure

There’s no denying the impact of stroke. Not only is it the third leading cause of death, but it is in many ways more feared than heart disease or cancer. As interventionists, our sights have turned to three controversial procedures: (1) carotid stenting, (2) left atrial appendage isolation, and (3) PFO closure. While the first two concern older patients, the third affects those younger and often in the prime of life, throwing patient and physician fears and preferences into the debate. The argument for PFO closure goes something like this: (1) patients with cryptogenic stroke, especially those under age 55 but also those older, have a higher prevalence of PFO; (2) PFO has been proven to cause stroke, most likely from paradoxical emboli; (3) observational studies have shown very low procedural complications and recurrent TIA/stroke after closure; (4) PFO closure may avoid long-term coumadin therapy in those with high-risk anatomy, and therefore; (5) PFO should be closed in patients with cryptogenic stroke, especially when there are high-risk features. The argument against closure, in contrast, goes something like this: (1) PFO closure carries procedural and long-term risk, and is also costly; (2) PFO closure has not been proven better than medical therapy after cryptogenic stroke in randomized clinical trials; (3) PFO is incredibly common, and therefore may be merely an innocent bystander; (4) prospective observational studies have failed to associate PFO with even a first stroke, and thus; (5) initial therapy should be medical (anti-platelet or anti-coagulant) with closure reserved only for failures. We as clinicians have three options: (1) encourage trial participation after a first cryptogenic stroke, (2) allow off-label closure based on observational studies, or (3) suggest patients continue medical therapy (anti-coagulant perhaps over anti-platelet therapy) until a second event. Now, we all know that it has been exceedingly difficult to enroll patients into randomized trials of closure versus medical therapy. For the majority of young patients, the unpredictable long-term safety and efficacy of medical therapy, as well as physician uncertainty over which medical therapy is best, are disconcerting. As a result, it has become hard to take a firm stance against PFO closure in young patients with cryptogenic stroke and high-risk anatomy, especially when meta-analyses of observational studies now show a recurrent TIA/stroke rate Dr. Srihari S. Naidu is Director of the Cardiac Catheterization Laboratory, Interventional Cardiology Fellowship Program and Hypertrophic Cardiomyopathy Center at Winthrop University Hospital on Long Island, and Assistant Professor of Medicine at SUNY – Stony Brook School of Medicine