PFO detection by saline contrast echocardiography

Patent foramen ovale (PFO) can cause paradoxical embolism and stroke. Hence in every case of stroke, it is necessary to look for a PFO. PFO typically shunts right to left at the end of a Valsalva maneuver. Hence injection of an agitated saline bolus at the end of a Valsalva maneuver and detection of the microbubbles in the left atrium within three cardiac cycles from the right atrial appearance would suggest presence of a PFO. Delayed appearance would indicate a pulmonary arteriovenous fistula. Sometimes injection from the lower limb is needed to detect a PFO because of the preferential streaming of the inferior vena caval blood towards the PFO as in fetal life. This is more likely if there is an associated Eustachian valve. Trans esophageal echocardiography (TEE) may be able to detect PFO better than trans thoracic echocardiography (TTE).

Source: Cardiophile MD - July 26, 2014 Category: Cardiology Authors: Prof. Dr. Johnson Francis MD, DM, FACC, FRCP Edin, FRCP London Tags: General Cardiology agitated saline bolus Eustachian valve microbubbles patent foramen ovale PFO PFO detection preferential streaming of the inferior vena caval blood pulmonary arteriovenous fistula right to left shunt saline contrast e Source Type: blogs