Enhanced detection of patent foramen ovale by systematic transthoracic saline contrast echocardiography.
OBJECTIVE
We aimed to evaluate the effectiveness of transthoracic saline contrast echocardiography (TSCE) in detecting patent foramen ovale (PFO).


BACKGROUND
Transesophageal echocardiography (TEE) is semi-invasive and not ideal for PFO screening.


METHODS
112 patients (48 males, 46 ± 14 years) with suspected PFO received intravenous agitated-saline contrast at rest and stress (strain and release phases of Valsalva maneuver and coughing). The presence of interatrial shunting was defined as >5 bubbles appearing in the left heart within 3 cardiac cycles. The stage of the maneuver at which interatrial shunting occurred was recorded. The TSCE findings were validated by TEE.


RESULTS
TEE identified PFO in 45% of patients. The sensitivities of TSCE in detecting PFO at rest, during strain and release of Valsalva maneuver, and coughing were 12.0%, 38.0%, 80.0% and 94.0% respectively (each p<0.05 when compared to previous stage). Specificities were similar and >95% for all stages. Moreover, the release phase of the maneuver improved the diagnostic accuracy [defined as (number of true positives+true negatives) divided by total in sample] with incremental value over the preceding strain phase (89.2 vs. 70.5%, p<0.001).


CONCLUSIONS
Patent foramen ovale can be identified confidently with proper conduct of the Valsalva maneuver during the transthoracic saline contrast echocardiography.
Lam
Yat-Yin
YY
Division of Cardiology, Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, Peoples’ Republic of China.
Yu
Cheuk-Man
CM
Zhang
Qing
Q
Yan
Bryan P
BP
Yip
Gabriel Wai-Kwok
GW
D000328:Adult; D003287:Contrast Media; D003371:Cough; D004452:Echocardiography / Q000379:methods*; D005260:Female; D054092:Foramen Ovale, Patent / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012146:Rest; D012680:Sensitivity and Specificity; D012965:Sodium Chloride; D014636:Valsalva Maneuver
D003287:Contrast Media; D012965:Sodium Chloride