Background/Aim To study the growth of left ventricular outflow tract (LVOT) after repair of ventricular septal defect (VSD) and aortic arch obstruction. Methods Retrospective review was done for all patients who underwent repair of VSD and aortic arch obstruction (coarctation or interrupted aortic arch) between July 2002 and Jun 2013. Echocardiographic data was reviewed. We evaluated the growth rate of LVOT and the need for reintervention. Results There were 93 patients with mean age of 30 ± 41 days and mean weight of 3.2 ± 1 kg. Sixty-six of them (70%) had coarctation and 27 (30%) had interrupted aortic arch. There is significant LVOT growth noticed after repair of VSD and aortic arch obstruction. 84 patients had negative Z-score of LVOT at diagnosis (mean −1.78 ± 0.9) which had grown significantly at last follow up (mean −1.29 ± 1.4, p = 0.003). Small LVOT was not a risk factor for LVOT obstruction. LVOT Z-score mean was −1.78 ± 0.9 versus −2.1 ± 0.75 in those who are free from reintervention versus those who had surgical reintervention, respectively (p = 0.17). Young age, small weight and small aortic valve annulus were not correlating with the risk of reintervention as well. Conclusion There is significant LVOT growth expected after repair of VSD and aortic arch obstruction. Small aortic valve and LVOT at diagnosis of those cases are not correlating with the need of surgical reintervention for LVOT obstruction.