[Behavioral situation at onset of paradoxical brain embolism due to patent foramen ovale].

The goal of this study was to determine whether there was difference in behavioral situation at onset of stroke between the patients with right-to-left shunt whose stroke was diagnosed as paradoxical brain embolism according to the new criteria proposed by Strategies against Stroke Study for Young Adults in Japan (SASSY-Japan) and whose stroke was not. Among 365 consecutive patients with possible acute ischemic stroke who underwent transesophageal echocardiography, we compared clinical profiles of the following three patient groups: patients with patent foramen ovale whose stroke was diagnosed as paradoxical brain embolism (group A), patients with patent foramen ovale whose stroke was not diagnosed as paradoxical brain embolism (group B), and patients without patent foramen ovale whose stroke was diagnosed as cardiogenic brain embolism (group C). Patent foramen ovale was present on echocardiogram in 76 of 365 patients (21%). Among them, 19 patients were classified into group A and 34 into group B. Group C was composed of 69 patients. At stroke onset, 3 patients in group A took behavior with positive Valsalva maneuver, 2 in group B, and 1 in group C. Similarly at stroke onset, 4 patients in group A just stood up from long-time sitting position, 1 in group B, and 1 in group C. In all, stroke onset following Valsalva maneuver or long-time sitting position was positive in 37% of group A, 9% of group B, and 3% of group C, and was most frequent in group A (p < 0.0001). In group A, the frequency of Valsalva maneuver or long-time sitting position at stroke onset was higher than the frequency of detection of venous thrombus (21%). The result indicates that Valsalva maneuver and long-time sitting position contribute to occurrence of paradoxical brain embolism. We think that these behavioral situations are appropriate diagnostic criteria for paradoxical brain embolism.