Despite the emerging relevance of high-density lipoprotein (HDL) in the inflammatory cascade and vascular barrier integrity, HDL levels in children undergoing cardiac surgery are unexplored. As a measure of HDL levels, the HDL-cholesterol (HDL-C) in single-ventricle patients was quantified before and after the Fontan operation, and it was determined whether relationships existed between the duration and the type of postoperative pleural effusions. The study prospectively enrolled 12 children undergoing the Fontan operation. Plasma HDL-C levels were measured before and after cardiopulmonary bypass. The outcome variables of interest were the duration and type of chest tube drainage (chylous vs. nonchylous). The Kendall rank correlation coefficient and the Wilcoxon rank sum test were used. There were 11 complete observations. The median preoperative HDL-C level for all the subjects was 30 mg/dl (range, 24-53 mg/dl), and the median postcardiopulmonary bypass level was 21 mg/dl (range, 14-46 mg/dl) (p = 0.004). There was a tendency toward a moderate inverse correlation (-0.42) between the postcardiopulmonary bypass HDL-C level and the duration of chest tube drainage, but the result was not statistically significant (p = 0.07). In the chylous effusion group, the median postcardiopulmonary bypass HDL-C tended to be lower (16 vs. 23 mg/dl; p = 0.09). After the Fontan operation, the plasma HDL-C levels in children are significantly reduced. It is reasonable to conclude that the reduction in HDL-C reflects reduced plasma levels of HDL particles, which may have pertinent implications in postoperative pleural effusions given the antiinflammatory and endothelial barrier functions of HDL.
KeywordsFontan; HDL-C; High-density lipoprotein-cholesterol Since the original description of the Fontan operation by Fontan and Baudet [8] in 1971, the procedure has undergone significant improvements in both the surgical and medical managements. These modifications have allowed a broad cross-section of patients with single-ventricle physiology to undergo successful Fontan palliation with excellent survival rates [1,13]. However, despite low mortality rates, patients who undergo the Fontan operation continue to remain at considerable risk for prolonged postoperative recovery complicated by persistent pleural effusions, ventricular dysfunction, arrhythmias, and protracted mechanical ventilation [18,21].Heart catheterization and echocardiographic evaluations are routinely performed before the Fontan operation in efforts to predict how the lungs and heart will interact. Yet, despite this practice, predicting the early postoperative course remains difficult, and it is becoming increasingly evident that catheterization hemodynamic data are not consistently associated with early postoperative outcomes [5,16]. This suggests the existence of other unexplored variables that place Fontan patients at risk for prolonged postoperative recovery despite acceptable hemodynamic criteria.In recent years, reductions in high-density lipoprotein (HDL) ...