“…However, in patients with complex CHD and no PVD, survival rate was significantly lower in patients with SpO 2 b 79% than those with SpO 2 ≧ 79%. Persistent severe hypoxia from birth along with erythrocytosis may have a negative impact on cardiac function [38,39] and myocardial structure [40,41], which may cause systemic complications and further deteriorate cardiac function to death due to cardiac failure and arrhythmias.…”