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Complete atrioventricular canal: comparison of modified single-patch technique with two-patch technique
Carl L Backer1, Robert D Stewart, Frédérique Bailliard
1Division of Cardiovascular Thoracic Surgery, and Cardiology, Children's Memorial Hospital, Chicago, IL 60614, USA. cbacker@childrensmemorial.org
Insights
The modified single-patch technique offers comparable outcomes to the two-patch technique for complete atrioventricular canal (CAVC) defects. This approach also significantly reduces cross-clamp and cardiopulmonary bypass times in infants.
Area of Science:
- Pediatric Cardiac Surgery
- Congenital Heart Defects
- Surgical Techniques
Background:
- Complete atrioventricular canal (CAVC) defects are complex congenital heart conditions.
- Surgical repair is essential for managing CAVC defects in infants.
- Two surgical techniques, the modified single-patch and the two-patch method, are commonly employed.
Purpose of the Study:
- To compare the efficacy and outcomes of the modified single-patch technique versus the two-patch technique for CAVC repair in infants.
- To evaluate differences in operative times, complication rates, and long-term results between the two surgical approaches.
Main Methods:
- A retrospective study of 55 infants undergoing CAVC repair between 2000 and 2006.
- Patients were divided into two groups: 26 receiving the modified single-patch technique and 29 receiving the two-patch technique.
- Demographic data, operative details, and postoperative outcomes were analyzed, including Rastelli classification and valve insufficiency.
Main Results:
- The modified single-patch group experienced shorter cross-clamp (97.3 vs 123.3 min) and cardiopulmonary bypass times (128 vs 157 min).
- No significant differences were observed in mortality, reoperation rates for mitral insufficiency or residual VSD, or AV valve insufficiency.
- Fewer patients in the single-patch group required pacemakers for AV block compared to the two-patch group.
Conclusions:
- The modified single-patch technique provides comparable results to the two-patch technique for CAVC repair in infants.
- This technique is associated with significantly reduced operative times, potentially leading to improved patient recovery.
- Both techniques demonstrate acceptable outcomes regarding valve function and need for reoperation.
Background:
The purpose of this study was to compare the modified single-patch technique to the two-patch technique for infants with complete atrioventricular canal (CAVC) defects.
Methods:
Between January 2000 and June 2006, 55 infants underwent CAVC repair. Twenty-six patients had a modified single-patch technique; 29 patients had a two-patch technique. Trisomy 21 was present in 23 of 26 and 26 of 29 patients (p = not significant [ns]). Mean age was 4.4 +/- 1.3 months (single-patch) versus 5.5 +/- 1.9 months (two-patch, p < 0.02). Mean weight was 4.74 +/- 0.92 versus 5.28 +/- 1.67 kilograms (p = ns).
Results:
There was one death in the modified single-patch group (postoperative day 130, liver failure) and no deaths in the two-patch group. Cross-clamp times and cardiopulmonary bypass times were shorter in the modified single-patch group (97.3 +/- 19.9 vs 123.3 +/- 28.2 minutes, p < 0.0003; 128 +/- 25 vs 157 +/- 37, p < 0.03). Rastelli classification was type A (18 vs 14), B (1 vs 0), and C (7 vs 15). Mean size of the ventricular septal defect as assessed by transesophageal echocardiogram was 9 +/- 2 mm, (single-patch) versus 10 +/- 3 mm (two-patch) (p = ns). Median postoperative length of stay did not differ (10 vs 8 days). There was no difference in the degree of postoperative left or right AV valve insufficiency as assessed by serial echocardiography. One patient (4%) required reoperation for mitral insufficiency in the modified single-patch versus three patients in the two-patch group (10%, p = ns). There were no patients with third degree atrioventricular block or that required reoperation for residual VSD in the modified single-patch group. There was one patient with third-degree AV block that required a pacemaker and one patient who had reoperation for a residual ventricular septal defect in the two-patch group (p = ns). No patient in either group required reoperation for left ventricular outflow tract obstruction.
Conclusions:
The modified single-patch technique produced results comparable with the two-patch technique in younger patients with similarly sized ventricular septal defects. Furthermore, the modified single-patch technique was performed with significantly shorter cross-clamp and cardiopulmonary bypass times.

