Pediatric Partial and Intermediate Atrioventricular Septal Defects Treatment & Management

Updated: Jan 24, 2019
  • Author: M Silvana Horenstein, MD; Chief Editor: Syamasundar Rao Patnana, MD  more...
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Medical Care

Treatment for congestive heart failure (CHF) is occasionally required if mitral regurgitation (MR) cannot be adequately surgically reduced.

Follow-up in patients with atrioventricular septal defect (AVSD) is determined on an individual basis, and the frequency depends on the persistence and severity of atrioventricular valve regurgitation or other abnormalities.

Chest radiography, electrocardiography (ECG), and echocardiography should be performed, if the physical examination warrants.


Obtain consultations with the following specialists:

  • Pediatric cardiologist

  • Cardiovascular surgeon

  • Geneticist, if an abnormality is suspected (eg, Down syndrome)


Surgical Care

Management of partial atrioventricular septal defect (AVSD) is primarily surgical, and repair includes patch closure of the atrial septal defect (ASD), mitral valve annuloplasty, or cleft closure. Other defects (eg, left ventricular outflow tract [LVOT] obstruction, patent ductus arteriosus [PDA]) may require repair during the same operation. [12]

Repair is usually electively performed in children aged 2-5 years, unless significant mitral regurgitation (MR) is present, in which case earlier repair is indicated. However, in the current era, repair of AVSD can be successfully performed in patients who weigh less than 5 kg. [13, 14, 15]

While the conventional timing for repair of partial AV septal defects is between the ages of 4 and 5 years, the recent trend has been to repair them early, before the age of 18 months. [16, 17, 18] However, the mortality rates (5.9%) are higher in the infant group; [18] this may in part be due to higher prevalence of unfavorable anatomy (poor left AV valve morphology and abnormalities of the subvalvar apparatus). A recent editorial on this subject suggests that repair in infancy may increase the early risk without accruing long-term benefit [19] On the basis of these considerations, it may be wise to follow the conventional approach of repair between the ages of 4 and 5 years. If repair in infancy is required because of heart failure, technique of cleft augmentation with a patch of autologous pericardium (instead simple cleft closure or repair with prosthetic patch material) may be useful in preventing late re-operations. [20, 21]

Surgical morbidity

Severe MR develops in a significant number of patients after correction of ASD. In fact, MR is the most common residual defect [16] and therefore, it is the most frequent indication for reoperation in patients after repair of both partial and complete AVSD. [22, 23, 24]

LVOT obstruction may not be evident for years after the initial repair. LVOT obstruction is the second most common indication for reoperation in patients with partial AVSD. [25, 26]

Preoperative severe left-sided atrioventricular valve regurgitation and associated valve malformations are important risk factors for postoperative development of MR. [22, 27]

According to another study, predictors for reoperation include postoperative MR, presence of major associated cardiac malformations, associated left atrioventricular valve malformations, partial or absent left atrioventricular valve cleft closure, and a weight of less than 5 kg. [13]

When the left-sided atrioventricular valve requires replacement because of unacceptable degrees of regurgitation, complete atrioventricular block (as well as higher mortality) are expected. [28]

Spontaneous regression of left-sided atrioventricular valve regurgitation after the immediate postoperative period has been described, thus avoiding the need for reoperation. [22]

Surgical mortality

Depending on the surgical series, early postoperative mortality rate is less than 3% in patients with mostly uncomplicated partial AVSD. [22, 29, 17] However, a multicenter study showed that the current survival rate from all types of AVSD repairs (in which 21.5% of patients had partial AVSDs and almost 12% had intermediate AVSDs) was 98-99%, of which 96-97% have no major complications. [30]

Poorer survival was seen in patients with major associated cardiac malformations and pulmonary hypertension, with an early postoperative mortality of 8%. [13] Poorer survival was also observed in patients who required reoperation, regardless of whether the procedure entailed AV valve repair or replacement. [26]