Patent foramen ovale is an important predictor of adverse outcome in patients with major pulmonary embolism.

BACKGROUND Right-to-left shunt through a patent foramen ovale is frequently diagnosed by contrast echocardiography and can be particularly prominent in the presence of elevated pressures in the right side of the heart. Its prognostic significance in patients with pulmonary thromboembolism, however, is unknown. METHODS AND RESULTS The present prospective study included 139 consecutive patients with major pulmonary embolism diagnosed on the basis of clinical, echocardiographic, and cardiac catheterization criteria. All patients underwent contrast echocardiography at presentation. The end points of the study were overall mortality and complicated clinical course during the hospital stay defined as death, cerebral or peripheral arterial thromboembolism, major bleeding, or need for endotracheal intubation or cardiopulmonary resuscitation. Patent foramen ovale was diagnosed in 48 patients (35%). These patients had a death rate of 33% as opposed to 14% in patients with a negative echo-contrast examination (P=.015). Logistic regression analysis demonstrated that the only independent predictors of mortality in the study population were a patent foramen ovale (odds ratio [OR], 11.4; P<.001) and arterial hypotension at presentation (OR, 26.3; P<.001). Patients with a patent foramen ovale also had a significantly higher incidence of ischemic stroke (13% versus 2.2%; P=.02) and peripheral arterial embolism (15 versus 0%; P<.001). Overall, the risk of a complicated in-hospital course was 5.2 times higher in this patient group (P<.001). CONCLUSIONS In patients with major pulmonary embolism, echocardiographic detection of a patent foramen ovale signifies a particularly high risk of death and arterial thromboembolic complications.