Ventricular function after anatomic repair in patients with atrioventricular discordance

Area of Science:

• Pediatric Cardiology
• Congenital Heart Surgery
• Cardiac Physiology

Background:

• Atrioventricular discordant anomalies represent complex congenital heart defects requiring specialized surgical intervention.
• The double switch operation aims to achieve anatomic correction in patients with these challenging conditions.
• Previous palliative procedures may have been performed, influencing surgical strategy and outcomes.

Purpose of the Study:

• To evaluate the outcomes of the double switch operation in pediatric patients with atrioventricular discordance.
• To assess the impact of the double switch operation on ventricular volumes, ejection fraction, and cardiac index.
• To identify patient subgroups that benefit most from this complex surgical procedure.

Main Methods:

• Retrospective analysis of 18 pediatric patients (<15 years) undergoing double switch operation since June 1989.
• Surgical techniques included Mustard or Senning procedures (atrial level) and arterial switch or conduit repair (ventriculoarterial level).
• Pre- and post-operative echocardiographic data were analyzed to assess ventricular function and dimensions.

Main Results:

• Two hospital deaths (11%) occurred; ages ranged from 1.4 to 12 years.
• Significant reduction in right ventricular end-diastolic volume (122.2% to 78.8%) was observed post-operation (p < 0.0003).
• Left ventricular function and volume remained unchanged; cardiac index averaged 3.1 L/min/m² post-operatively.

Conclusions:

• The double switch operation is a viable treatment for pediatric atrioventricular discordance, with acceptable mortality.
• The procedure effectively unloads the right ventricle, leading to significant volume reduction.
• This operation is particularly indicated for patients with systemic tricuspid regurgitation and/or impaired systemic right ventricular function.