Pulmonary arterial hypertension, a common consequence of untreated CHD, is associated with a significant morbidity and mortality. Recent researches have demonstrated that patients with clinically severe cardiovascular illnesses, including pulmonary hypertension, have a greater mortality risk when their red cell distribution width is high. This work aimed to assess the predictive value of red cell distribution width in children with pulmonary arterial hypertension-CHD and to correlate red cell distribution width with various clinical and echocardiographic data.

Sixty patients with CHD associated with pulmonary arterial hypertension were enrolled as the patient group. Another 60 patients with CHD and no pulmonary arterial hypertension, matched for age and sex, were enrolled as the control group. Electrocardiography and echocardiographic evaluation were performed for all included children. Red cell distribution width as part of the complete blood count was also performed using a Coulter® LH 700 series haematology analyzer.

The red cell distribution width was significantly higher in the pulmonary arterial hypertension-CHD group than in the CHD-only group (P < 0.05). There was a significant positive correlation between the red cell distribution width and mean pulmonary artery pressure. Red cell distribution width was an independent predictor of mortality in children with pulmonary arterial hypertension-CHD. The best red cell distribution width cut-off for predicting mortality in children with pulmonary arterial hypertension-CHD was ≥ 17.6%.

Red cell distribution width was significantly higher in children with pulmonary arterial hypertension–CHD than in those without pulmonary arterial hypertension. Moreover, red cell distribution width could be a cheap easy predictive marker for mortality in children with pulmonary arterial hypertension-CHD.

The aim of the present study was to explore the predictive value of red cell distribution width as a means to differentiate between neurally mediated syncope and arrhythmic syncope in children.

Patients were divided into a neurally mediated syncope group (n=72) and an arrhythmic syncope group (n=21) on the basis of clinical history, results of the head-up tilt test, electrocardiography, and 24-hour ambulatory electrocardiography. As controls, we recruited 55 healthy children. Red cell distribution width was determined for children in all groups. A receiver operating characteristic curve was drawn to study the predictive effect of red cell distribution width to differentiate between neurally mediated syncope and arrhythmic syncope.

Red cell distribution width was significantly higher in children with neurally mediated syncope than in children with arrhythmic syncope and the control group. A receiver operating characteristic curve on the predictive value of red cell distribution width in differentiating neurally mediated syncope from arrhythmic syncope showed that the area under the curve was 0.841 (95% confidence interval: 0.737–0.945, p<0.05). A red cell distribution width value of 12.8% as the cut-off value yielded a sensitivity of 80.6% and a specificity of 76.2% in discriminating between patients with neurally mediated syncope and arrhythmic syncope.

Red cell distribution width value of ⩾12.8% might be a useful adjunct for primary-care physicians to differentiate neurally mediated syncope from arrhythmic syncope in children.