The cough test is superior to the Valsalva maneuver in the delineation of right-to-left shunting through a patent foramen ovale during contrast transesophageal echocardiography

A patent foramen ovale may result in paradoxical embolization and serious morbidity. Thus a sensitive method to diagnose a patent foramen ovale is important. It is unknown whether the cough test or the Valsalva maneuver is superior in delineating right-to-left shunting through a patent foramen ovale during contrast transesophageal echocardiography. Thus we studied 73 consecutive patients (53 men and 20 women), aged 54 ± 16 years (range 18 to 79 years), during elective transesophageal echocardiography. Contrast transesophageal echocardiography was performed from a four-chamber view during quiet respirations, Valsalva maneuver, and cough test. In the entire group the incidence of a patent foramen ovale was higher during the cough test (3273) as compared with the Valsalva maneuver (2473, p < 0.025) and quiet respirations (1873, p < 0.005). All subjects with a patent foramen ovale during the Valsalva maneuver had a positive contrast transesophageal echocardiogram during the cough test. In subjects (n = 55) without a patent foramen ovale during quiet respirations, the incidence of a patent foramen ovale was higher during the cough test (1555) as compared with the Valsalva maneuver (955, p < 0.05). In a subgroup (N = 17) of patients with nonhemorrhagic stroke (n = 11), transient ischemic attack (n = 2), or peripheral embolus (n = 4), the cough test had a higher yield (917) in delineating a patent foramen ovale as compared with the Valsalva maneuver (717) but did not reach statistical significance. These data demonstrate that the cough test is superior to the Valsalva maneuver in delineating a patent foramen ovale during contrast transesophageal echocardiography. The cough test should be considered the maneuver of choice when attempting to delineate a patent foramen ovale during contrast transesophageal echocardiography.