Propensity Score-Matched Analysis Comparing Modified Konno Procedure and Transaortic Septal Myectomy in Children With...

Area of Science:

• Pediatric Cardiac Surgery
• Cardiovascular Surgery
• Congenital Heart Disease

Background:

• Comparative outcomes of modified Konno procedure (MKP) and transaortic septal myectomy (TSM) for pediatric severe left ventricular outflow tract (LVOT) obstruction are not well-defined.
• Severe LVOT obstruction requires effective surgical intervention in pediatric patients.

Purpose of the Study:

• To compare the clinical outcomes of MKP and TSM in children with severe LVOT obstruction.
• To evaluate the efficacy and safety of MKP versus TSM in pediatric patients.

Main Methods:

• A cohort of 177 pediatric patients (<14 years) undergoing surgical treatment for LVOT obstruction was analyzed.
• Patients were categorized into MKP (n=45) and TSM (n=132) groups, with propensity-score matching creating a 1:1 cohort (45 patients each).

Main Results:

• MKP demonstrated significantly lower LVOT peak gradients at discharge and follow-up compared to TSM.
• While atrioventricular block was more frequent post-MKP, permanent pacemaker implantation rates did not differ significantly between groups.
• The incidence of recurrent LVOT obstruction was substantially higher in the TSM group (17.8%) versus the MKP group (0%).
• Smaller aortic annulus size and higher preoperative LVOT peak gradient were associated with recurrent obstruction.

Conclusions:

• MKP provides superior relief of LVOT obstruction in young children, especially those with small aortic annuli or severe obstruction.
• MKP does not appear to increase the risk of permanent pacemaker implantation or mortality.
• MKP represents a potentially more effective surgical option for specific pediatric LVOT obstruction cases.