Transosophageale echokardiographie und transkranielle dopplersonographie mit ultraschallkontrastmittel sind 'erganzende, nicht konkurrierende methoden'

Background: The prevalence of patent foramen ovale (PFO) in healthy individuals is estimated to be about 25% and is elevated to 40% patients with stroke. To date transesophageal echocardiography (TEE) was considered to be the most sensitive method to detect PFO and was regarded as the gold standard. Transcranial Doppler sonography of the middle cerebral artery during contrast injection (c-TCD) has recently been proposed as an alternative method for the detection of PFO. We report our experience on 45 patients (age < 55 years) with stroke or transient ischemic attack (TIA) in whom both c-TCD and TEE were performed to detect PFO as a mechanism for embolic cerebral ischemia. Patients and Methods: In 45 patients (21 women, 24 men, mean age 41,4 years ranging from 17 to 54 years) with cerebral ischemia, both standardized TEE and standardized c-TCD were performed separately. When any PFO was found by TEE and/or c-TCD, it was classified as positive. If c- TCD was positive but TEE negative, a second TEE was performed and vice versa. Results: PFO was found epicritically in 26 patients (57.8%). First TEE detected PFO in 24 cases (sensitivity 92.3%). Separately performed c-TCD detected PFO in 22 cases of the PFO-positive cases (sensitivity 84.6%). However, c-TCD detected PFO in 2 cases, in which the first TEE had been negative, leading to a second TEE which confirmed PFO and demonstrated minimal shunt (7.7%). TEE detected PFO in 4 cases in which first c-TCD was negative. A second c-TCD confirmed in 2 of these 4 cases a positive right- to-left shunt. Neither method revealed false positive results (specifity 100%). The positive predictive value was 100% in both methods. The negative predictive value in TEE was 90.5% and in c-TCD was 82.6%. Conclusion: TEE and c-TCD are not concurrent diagnostic tools to detect PFO. Both supplement each other. If both methods are used in all PFO-suspected patients, PFO detection rate is higher than when using either method alone.