Atrial septal defect contrast echocardiography


 * Associate Editor(s)-In-Chief: Priyamvada Singh, M.B.B.S. [mailto:psingh@perfuse.org], ; Assistant Editor(s)-In-Chief: Kristin Feeney, B.S. [mailto:kfeeney@perfuse.org]

For a full discussion on the usage of echocardiography for atrial septal defect diagnosis click here.

Overview
Echocardiography is the preferred diagnostic tool in the evaluation of an atrial septal defect. Contrast echocardiography is an effective modality that can be performed in individuals with a suspected atrial septal defect which is not visualized definitively on transthoracic imaging.

Contrast echocardiography

 * Used to determine the presence of intercardiac shunting often seen in the apical four chamber view
 * Agitated saline is commonly used as the contrast material.
 * Saline contrast can visualize heart function, problems in the left ventricle, and problems in the surrounding valves.
 * Injected into a peripheral vein during echocardiography, small air bubbles can be seen on the imaging.
 * It may be possible to see bubbles travel across an atrial septal defect either at rest or during a cough.
 * Bubbles will only flow from right atrium to left atrium if the RA pressure is greater than LA

Common Findings

 * A right-to-left interatrial shunt can be seen:
 * When an atrial septal defect with accompanying pulmonary hypertension, resulting in a left-to-right reversal.
 * Any time a patent foramen ovale defect is present.
 * When an uncomplicated atrial septal defect has an imbalance in right-sided pressure, such as from coughing or the Valsalva maneuver.
 * When an uncomplicated atrial septal defect has a momentary onset of left ventricular contraction.

Sensitivity

 * Not recommended for:
 * Left-to-right interatrial shunt diagnosis
 * Pregnant patients
 * Patients with severe pulmonary hypertension

Disadvantages

 * False positives in the setting of a pulmonary arteriovenous malformation
 * Difficulty in quantifying the size of the shunt

==ACC / AHA Guidelines - Evaluation of the Unoperated Patient (DO NOT EDIT) == {{cquote|

Class I
1) ASD should be diagnosed by imaging techniques with demonstration of shunting across the defect and evidence of RV volume overload and any associated anomalies. (Level of Evidence: C)

2) Patients with unexplained RV volume overload should be referred to an ACHD center for further diagnostic studies to rule out obscure ASD, partial anomalous venous connection, or coronary sinoseptal defect. (Level of Evidence: C) }}