Endocardial Cushion Defects (Atrioventricular Canal Defects, Atrioventricular Septal Defects) Treatment & Management

Updated: Dec 28, 2020
  • Author: Mary C Mancini, MD, PhD, MMM; Chief Editor: Yasmine S Ali, MD, MSCI, FACC, FACP  more...
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Medical Care

Medical treatment for endocardial cushion defect (atrioventricular [AV] canal or septal defect) is designed to relieve the symptoms of congestive heart failure (CHF) until operative correction is feasible. The objective of therapy is to avoid development of pulmonary vascular obstructive disease. When heart failure and associated pulmonary congestion are present, diuretics and digoxin are indicated.

Postoperative recovery requires 5-10 days of hospitalization, depending upon the condition of the child prior to surgery and whether palliative or complete correction is undertaken. With palliation (ie, pulmonary artery banding), the presurgical condition of volume overload still must be regulated. With complete correction, recovery generally is uneventful.

Diet and activity

For infants in CHF, discretion with fluid intake and salt use is encouraged.

Rest during feeding is encouraged, because one manifestation of dyspnea in these infants is the inability to feed. Generally, the child limits activity without encouragement.

Outpatient care

Continued observation is needed with regularly scheduled echocardiography in order to assess the integrity of the AV valvular reconstruction. This area is prone to development of valvular insufficiency that may require further intervention as the child grows older.


Surgical Care

See also the Guidelines section for American Heart Association/American College of Cardiology (2018) [10] and European Society of Cardiology (2020) [11, 12] ​ recommendations.

Infants with partial endocardial cushion defect (atrioventricular [AV] canal or septal defect [AVSDs]) that are symptomatic are referred for corrective surgery, which includes mitral valvuloplasty and closure of the atrial septal defect. Asymptomatic patients with an ostium primum defect are referred for elective repair after infancy.

Patients with complete AVSDs who do not have associated right ventricular (RT) outflow obstruction (OTO) generally have pulmonary artery pressures near systemic levels. These patients will develop pulmonary vascular disease after the first year of life and usually are referred for corrective surgery in infancy.

Historically, children were treated with pulmonary artery banding in infancy to protect the pulmonary vasculature from excessive blood flow and development of pulmonary vascular disease. Patients were referred for corrective surgery when older than 3-4 years.

Corrective surgery can be performed even in early infancy, in several ways. A single Dacron patch can be used to close the atrial and ventricular septal defect (see image below). The right and left portions of the common AV valve are then resuspended from the patch. A two-patch technique also may be used.

Endocardial Cushion Defects (Atrioventricular Cana Endocardial Cushion Defects (Atrioventricular Canal Defects, Atrioventricular Septal Defects). Repair of the endocardial cushion defect. The patch is covering the ostium primum atrial septal defect.

Severe and irreversible pulmonary vascular disease is a contraindication to corrective surgery, and these children may be referred for cardiopulmonary transplantation. [13, 14, 15, 16]

In a study that evaluated trans-left AV valve (LAVV) blood flow in patients after AVSD correction and in healthy controls, 25 patients after AVSD correction and 25 controls underwent 4DFlow magnetic resonance imaging (MRI). [17] Streamline visualization of 4DFlow MRI data showed dynamic trans-LAVV inflow and increased lateral flow after AVSD correction.

Ginde and colleagues examined the outcomes of complete AVSD (CAVSD) repair in 198 patients who underwent surgical repair for CAVSD at their institution between 1974 and 2000. [18] Overall perioperative mortality was 10.1%, with a significant decrease to 2.9% in the surgical era of 1991 to 2000. For the entire cohort, the overall estimated survival was 85% at 10 years, 82% at 20 years, and 71% at 30 years after initial CAVSD repair. [18]



The current limited knowledge of the genetic abnormalities that predispose to the formation of the endocardial cushion defect can be expanded greatly with current advances in the Human Genome Project. As the knowledge base expands, prenatal detection and possibly treatment may be possible in the future.