It occurs at least every other week in my own clinical experience. A patient has experienced an ischemic stroke, and after a workup that fails to show significant atherosclerosis (“hardening of the arteries,” “plaque build-up”) in the arteries leading to the part of the brain injured by the stroke, and without obvious risk factors that could have resulted in stroke, an echocardiogram identifies the presence of a patent foramen ovale (PFO). Often patients are told a PFO is a “hole in the heart,” allowing clots to reach the brain that would otherwise end up in the lungs as their final destination. I see in their notes: “Stroke caused by PFO.” Some patients arrive to the appointment, already having determined they want their PFOs closed, and others have already concluded just the opposite – no “heart surgery.” The majority feel lost and are seeking answers. What is a PFO, and what is the significance of it? The purpose of this post is outlined in the title – to remove some of the mystery from the PFO, although its potential effects and clinical associations with it are, indeed, still mysterious. A foramen ovale (“FO” – if you will) is a very normal part of a fetus’s […]