Atrial septal defect trans-cranial doppler ultrasound


 * 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

Overview
Trans-cranial doppler ultrasound is a diagnostic tool that involves a simple intravenous injection of saline under minimal sedation. It is primarily utilized to further diagnostically evaluate a patent foramen ovale defect.

Transcranial Doppler Ultrasound

 * Transcranial Doppler Ultrasound Bubble test can be used to determine hemodynamic interaction between atriums of the heart
 * Non-invasive ultrasound method
 * Operated by a hand-held Doppler transducer that functions on a pulsating low-frequency
 * Requires no sedation
 * Involves a simple intravenous injection of saline solution
 * Used as a testing standard in clinical trials of patent foramen ovale closure devices and in studies ivestigating the relationship and interconnectivity of patent foramen ovale, stroke and migraines.

Indications

 * Effective in detecting narrowing of cerebral arteries
 * Effective in measuring hemodynamic circulation patterns within occluded diseased cerebral arteries
 * Effectively measures:
 * Peak systolic velocity
 * Peak diastolic velocity
 * Mean velocity
 * Pulsitility

Advantages

 * Usage of Valsalva manuever during testing can increase the visibility and overall detection of an atrial septal defect
 * Less invasive than other methods
 * Cost effective
 * Can be completed in under an hour

Common Findings

 * A defect may present in two ways:
 * Small right-to-left shunt at start of systole (biphasic), associated with patent foramen ovale
 * Larger left-to-right shunt, associated primarily with atrial septal defect


 * Visualization of bubbles in the left atrium and left ventricle

==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) }}

Supportive Trial Data

 * Transcranial Doppler ultrasound Bubble study has minimal or no complications.
 * One study which detected an incidence of adverse events of 0.3% or greater and found 0 events; indicating a high confidence interval (alpha value was 0.05).