AIM  To evaluate the surgical management strategy and follow-up of complete atrioventricular septal defect (cAVSD) infant-patients complicated with pulmonary artery hypertension (PAH) at high altitude.

METHODS 28 children under 2 years old with cAVSD and PAH were selected for primary correction from December 2009 to December 2021, including 15 males and 13 females, aged (2.5～21) months, with a body mass of (2.5～11.0) kg. Among them, 15 patients with moderate or above pulmonary hypertension were included in Group A. Thirteen patients with mild and normal pulmonary arterial pressure were assigned to Group B. Compare the ICU hospitalization time, ventilator intubation time, aortic occlusion time, overall hospitalization time, and mortality rate between the two groups of patients. And conduct follow-up. During the operation, improved single slice method was used in 3 cases, double slice method in 25 cases, direct suture of left atrioventricular valve holes was performed in 17 cases, hole patch widening and tendon cord transplantation was performed in 1 case, and left atrioventricular valve posterior annulus reconstruction was performed in 3 cases.

RESULTS There was no statistical difference in age, body mass, Rastelli classification, Down syndrome, common valve regurgitation and ventricular septal defect size between the two groups. Compared with Group B, the duration of ventilator intubation in Group A was significantly longer (P<0.05), while there were no significant differences in other indicators such as ICU hospitalization time, overall hospitalization time, aortic occlusion time, and mortality rate. Compared with Group A, Group B had a lower proportion of mild left atrioventricular valve regurgitation (P<0.05), while there were no significant differences in residual ventricular septal shunt, moderate to severe left atrioventricular valve regurgitation, right atrioventricular valve regurgitation, complete atrioventricular block, and early postoperative death in other items. The follow-up time of all children after surgery was (8 ± 3) years. The statistical results of cardiac echocardiography follow-up were: 18 cases of mild mitral insufficiency, 5 cases of moderate mitral insufficiency, 2 cases of severe Tricuspid valve insufficiency, 19 cases of mild tricuspid insufficiency, 4 cases of moderate tricuspid insufficiency, and 2 cases of severe tricuspid insufficiency. Two patients with severe mitral insufficiency received valve repair/replacement again. None of the surviving patients in the whole group had left ventricular outflow tract stenosis. One patient had severe Tricuspid valve regurgitation, and two patients had moderate regurgitation. The three death cases in Group A were classified as severe mitral regurgitation in 1 case, moderate regurgitation in 1 case, and mild regurgitation in 1 case based on the patient’s last ultrasound evaluation in the intensive care unit.

CONCLUSION Infants with cVASD at high altitude should be treated as early as possible, The key to success is the effect of valvuloplasty and avoidance of complete atrioventricular block, and the insufficient valvuloplasty of left atrioventricular valve is a most common cause for post-operative death and re-intervention in the medium or long term.