Need for performance protocols in TEE and TCD for detection of right to left shunts.
OBJECTIVE
Although transesophageal echocardiography (TEE) is the gold standard for right to left shunt detection, we observed that transcranial Doppler (TCD) was more sensitive and sought an explanation.


METHODS
We retrospectively evaluated results of TCD and TEE in 118 patients with cryptogenic stroke and transient ischemic attacks. TCDs were done as per modification of a published performance protocol and interpreted by a neurologist and radiologist. TEEs were performed and interpreted by five cardiologists without standardized protocol. Statistical methodology included χ(2) tests, Fisher exact tests, and ANOVA.


RESULTS
Overall agreement between TCD and TEE was found for 76 of 118 patients. Sensitivities of TCD and TEE were 93.8% and 53.1%. Sensitivities for TCD interpreters were 61.1% and 64.1%. Sensitivities for TEE operators varied from 46.7% to 75.7%. We were unable to find a performance protocol for TEE microbubble studies in either published literature or certification organizations.


CONCLUSIONS
TEEs and TCDs are operator dependent and thus subject to false negatives. The lower yield and interoperator variability in TEE results appear to reflect the lack of performance protocols and engender concern about false negatives in community use. Consensus performance protocols and certification criteria for both modalities should have an impact on accuracy of shunt detection.
Neurology Department, Barrow Neurological Institute, Phoenix, AZ.
Jason
J
Chang
Carol
C
Darbonne
Denise A
DA
Drumm
Mohamed S
MS
Teleb
James L
JL
Frey
D000293:Adolescent; D000328:Adult; D000368:Aged; D017548:Echocardiography, Transesophageal / Q000379:methods* / Q000592:standards; D005260:Female; D054092:Foramen Ovale, Patent / Q000150:complications* / Q000000981:diagnostic imaging*; D006801:Humans; D002546:Ischemic Attack, Transient / Q000000981:diagnostic imaging* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D020380:Needs Assessment; D015588:Observer Variation; D017410:Practice Guidelines as Topic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods* / Q000592:standards; D014481:United States; D055815:Young Adult