Comparison of transesophageal and transthoracic contrast echocardiography for detection of a patent foramen ovale

Presence of a patent foramen ovale may indicate paradoxic embolism in patients with otherwise unexplained embolie disease. 1–3 Transthoracic contrast echocardiography has been used as a simple technique for detecting patent foramen ovale. 4–6 However, particularly in patients with poor transthoracic image quality, presence of a patent foramen ovale might be missed. Transesophageal contrast echocardiography provides superior visualization of the atrial septum and therefore is believed to improve diagnostic accuracy. The present study investigates the influence of image quality on the detection of a patent foramen ovale by both transthoracic and transesophageal contrast echocardiography.