The prognostic implications of perioperative endogenous hydrogen sulfide and nitric oxide levels in children with congenital heart disease complicated by pulmonary arterial hypertension.

The goal of this study was to measure perioperative changes in endogenous hydrogen sulfide (H2S) and nitric oxide (NO) levels in children with congenital heart disease (CHD) complicated by pulmonary arterial hypertension (PAH), with the goal of better monitoring these children and evaluating their prognosis. For this study, we enrolled 48 normal control cases, 48 preoperative CHD cases including 16 without PAH, 16 with mild PAH, and 16 with moderate-to-severe PAH. We additionally enrolled a cohort of 32 other children with PAH-CHD that had undergone CHD correction prior to transfer to an intensive care unit (ICU). These children were further subdivided based on whether or not PAH was still present after operation (n = 16 per group). Spectrophotometry was used to assess endogenous H2S and NO levels at 24 and 48 h postoperatively in each group. Correlations between postoperative endogenous H2S and NO levels at these two time points, as well as duration of mechanical ventilation, ICU length of stay, duration of hospitalization, and vasoactive drug score values at 24 and 48 h postoperation were assessed. Endogenous H2S and NO values differed significantly between the control and preoperative CHD groups (P < 0.05). These values also differed significantly among the three different preoperative CHD subgroups and were negatively correlated with pulmonary arterial pressure (P < 0.05). Spearman rank correlation analyses indicated that endogenous H2S levels at 24 and 48 h postoperation were negatively correlated with the duration of mechanical ventilation, ICU length of stay, and maximum vasoactive drug score values at both 24 and 48 h postoperation. We similarly identified a negative correlation between NO concentrations at 24 and 48 h postoperation and maximum vasoactive drug score at these same time points (P < 0.05).Conclusions: Endogenous H2S and NO levels are closely associated with CHD-PAH incidence, and there is a correlation between endogenous H2S levels and the postoperative prognosis of CHD in children. Higher H2S concentrations seem to correspond to better patient prognosis, and as such these values can be used as a prognostic index at an early time point. These values can additionally guide treatment efforts and improve outcomes among children with CHD-PAH. What is Known: • Hydrogen sulfide and nitric oxide are both vasodilating factors. • Hydrogen sulfide and nitric oxide can regulate pulmonary vascular remodeling, which is closely related to the occurrence and prognosis of pulmonary arterial hypertension. What is New: • This study was designed to explore the relationship between short-term prognostic indexes and hydrogen sulfide and nitric oxide levels, in an effort to provide a frame of reference for the postoperative monitoring and treatment of children with congenital heart disease complicated by pulmonary arterial hypertension.