Enhanced detection of right-to-left shunt through patent foramen ovale by transthoracic contrast echocardiography using harmonic imaging.

When the results of transesophageal echocardiography was regarded as the gold standard for detecting a patent foramen ovale (PFO) in 136 consecutive patients referred for evaluation of cardiac source of embolism, transthoracic harmonic imaging using saline contrast was superior to fundamental imaging in accuracy for detecting a PFO (sensitivity, 22.5%; specificity [p < 0.05] and sensitivity, 100%; specificity 100%, respectively.)