Atrial septal defect overview

Atrial Septal Defect Microchapters
Home
Patient Information
Overview
Anatomy
Classification
Ostium Secundum Atrial Septal Defect
Ostium Primum Atrial Septal Defect
Sinus Venosus Atrial Septal Defect
Coronary Sinus
Patent Foramen Ovale
Common or Single Atrium
Pathophysiology
Epidemiology and Demographics
Risk Factors
Natural History and Prognosis
Complications
Diagnosis
History and Symptoms
Physical Examination
Electrocardiogram
Chest X Ray
CT
MRI
Echocardiography
Transesophageal Echocardiography
Transthoracic Echocardiography
Contrast Echocardiography
M-Mode
Doppler
Transcranial Doppler Ultrasound
Cardiac Catheterization
Exercise Testing
ACC/AHA Guidelines for Evaluation of Unoperated Patients
Treatment
Medical Therapy
Surgery
Indications for Surgical Repair
Surgical Closure
Minimally Invasive Repair
Robotic ASD Repair
Percutaneous Closure
Post-Surgical Follow Up
Special Scenarios
Pregnancy
Diving and Decompression Sickness
Paradoxical Emboli
Pulmonary Hypertension
Eisenmenger's Syndrome
Atmospheric Pressure
Case Studies
Case #1
Atrial septal defect overview On the Web
Most recent articles
Most cited articles
Review articles
CME Programs
Powerpoint slides
Images
American Roentgen Ray Society Images of Atrial septal defect overview All Images X-rays Echo & Ultrasound CT Images MRI
Ongoing Trials at Clinical Trials.gov
US National Guidelines Clearinghouse
NICE Guidance
FDA on Atrial septal defect overview
CDC on Atrial septal defect overview
Atrial septal defect overview in the news
Blogs on Atrial septal defect overview
Directions to Hospitals Treating Type page name here
Risk calculators and risk factors for Atrial septal defect overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Claudia Hochberg, M.D.

Associate Editors-In-Chief: Cafer Zorkun, M.D., Ph.D. [2]; Keri Shafer, M.D. [3]; Priyamvada Singh, MBBS [[4]]

Assistant Editor-In-Chief: Kristin Feeney, B.S. [[5]]

Overview

Atrial septal defects (ASD) are a group of congenital heart diseases that involve the inter-atrial septum. The inter-atrial septum is the tissue that separates the right and left atria from each other. This tissue prevents arterial and venous blood from mixing with each other. If there is a defect in this septum, a direct communication between the atria can occur, which allows shunting, resulting in mixing of arterial and venous blood. It is possible for blood to travel from the left side of the heart to the right side of the heart, or vice versa.

The direction of shunting will depend on a variety of factors, notably the patient's hemodynamics. If the pressures are higher in the right atrium than the left atrium, blue cyanotic blood will flow from the right atrium into the lower pressure left atrium. A "Right-to-left-shunt" as described above may pose a more dangerous scenario (See Pathophysiology below). Since the right side of the heart contains venous blood with a low oxygen content, and the left side of the heart contains arterial blood with a high oxygen content, right to left shunts can cause hypoxia and result in cyanosis. Additionally, a communication between the two atria may allow blood clots to pass from the venous system to the arterial system and result in a stroke or peripheral embolism.