Transesophageal echocardiography and contrast-TCD in the detection of a patent foramen ovale: experiences with 111 patients.
Patent foramen ovale (PFO) is increasingly recognized in association with cryptogenic stroke. Using transesophageal echocardiography (TEE) and transcranial Doppler sonography with ultrasonic contrast medium (contrast-TCD), we evaluated the frequency of a PFO as the fundamental condition of paradoxical embolism in 111 patients after cerebral ischemia. There was a right-left shunt in 50 patients (45%) with TEE. In 31 of 40 patients with stroke of unknown etiology, a PFO was the only detectable finding associated with cerebral ischemia. Using TEE as the "gold standard," the sensitivity of contrast-TCD was 91.3%, specificity 93.8%, and the overall accuracy 92.8%. Contrast-TCD failed to detect a right-left shunt in four patients, but there were four other patients with negative TEE and positive contrast-TCD. We conclude that contrast-TCD is a highly sensitive method for detecting a right-left shunt. Its advantages are low cost, its ability to detect single contrast-medium embolism, and control of the Valsalva maneuver by observing the decrease of cerebral blood flow. Evidence of PFO in cryptogenic stroke should prompt a search for a subclinical venous thrombosis as the embolic source.
Klötzsch
C
C
Department of Neurology, Alfried-Krupp-Hospital, Essen, Germany.
Janssen
G
G
Berlit
P
P
D000368:Aged; D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000209:etiology*; D002561:Cerebrovascular Disorders / Q000209:etiology; D003287:Contrast Media; D015150:Echocardiography, Doppler; D017548:Echocardiography, Transesophageal; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000150:complications / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged
D003287:Contrast Media