RESUMEN
Background: The late postoperative course for children with transposition of the great arteries [TGA] with an intact ventricular septum [IVS] is very important because the coronary arteries may be at risk of damage during arterial switch operation [ASO]. We sought to investigate left ventricular function in patients with TGA/IVS by echocardiography
Methods: From March 2011 to December 2012, totally 20 infants [12 males and 8 females] with TGA/IVS were evaluated via 2-dimensional speckle-tracking echocardiography [2D STE] more than 6 months after they underwent ASO. A control group of age-matched infants and children was also studied. Left ventricular longitudinal strain [S], strain rate [SR], time to peak systolic longitudinal strain [TPS], and time to peak systolic longitudinal strain rate [TPSR] were measured and compared between the 2 groups
Results: Mean +/- SD of age at the time of study in the patients with TGA/IVS was 15 +/- 5 months, and also age at the time of ASO was 12 +/- 3 days. Weight was 3.13 +/- 0.07 kg at birth and 8.83 +/- 1.57 kg at the time of ASO. Global strain [S], Time to peak strain rate [TPSR], and Time to peak strain [TPS] were not significantly different between the 2 groups, whereas global strain rate [SR] was significantly different [p value < 0.001]. In the 3-chamber view, the values of S in the lateral, septal, inferior, and anteroseptal walls were significantly different between the 2 groups [p value < 0.001], and SR in the posterior wall was significantly different between the 2 groups [p value < 0.001]. There were no positive correlations between S and SR in terms of the variables of heart rate, total cardiopulmonary bypass time, and aortic cross-clamp time. There were no statistically significant differences between the 2 groups regarding S, SR, TPS, and TPSR in the anteroseptal and posterior walls in the 3-chamber view and in the lateral and septal walls in the 4-chamber view
Conclusion: We showed that between 6 and 18 months after a successful ASO, the parameters of S, SR, and global TPS were normal in our patients with TGA/IVS. However, LV myocardial TPSR did not normalize in this time period