[Contrast echocardiography in patients with insignificant interatrial communications (patent foramen ovale) (author's...

Peripheral M-mode contrast echocardiograms at rest and during the Valsalva manoeuvre were performed in 9 patients with haemodynamically insignificant interatrial communications. Contrast echoes appeared in the left heart in all 4 patients with elevated right ventricular pressure, but also in 3 out of the 5 patients with normal right-side pressures. Thus, a positive contrast echocardiogram, while definitely proving the presence of an intracardiac communication, does not necessarily mean that the defect is haemodynamically significant. The ability to detect a patent foramen ovale non-invasively by contrast echocardiography may be useful in patients with suspected paradoxical embolism.