Characteristics and prospective 2-year follow-up of children with pulmonary arterial hypertension in France.

BACKGROUND: Limited data are available describing paediatric pulmonary arterial hypertension. AIMS: To characterize the epidemiology, management and impact on quality of life and outcome of paediatric pulmonary arterial hypertension, excluding persistent pulmonary hypertension of the newborn and pulmonary arterial hypertension caused by congenital heart disease. METHODS: In this multicentre study, children with pulmonary arterial hypertension were included and followed prospectively for two years at 21 referral centres in France. WHO functional class, 6-minute walk distance and quality of life (CHQ-PF50 questionnaire) were evaluated. RESULTS: Fifty children were included with a mean age of 8.9 +/- 5.4 years from May 2005 until June 2006. The estimated prevalence for pulmonary arterial hypertension was 3.7 cases/million. Patients had idiopathic pulmonary arterial hypertension (60%), familial pulmonary arterial hypertension (10%), pulmonary arterial hypertension associated with, but not caused by, congenital heart disease (24%), pulmonary arterial hypertension associated with connective tissue disease (4%) or portal hypertension (2%). During follow-up, the combination of pulmonary arterial hypertension-specific therapies was increasingly prescribed (44% patients versus 22% at inclusion). Patients remained stable regarding clinical status, 6-minute walk distance and quality of life. Survival estimates after one and two years were 86% (95% CI 76, 96) and 82% (95% CI 71, 93), respectively. CONCLUSIONS: In children, idiopathic/familial pulmonary arterial hypertension accounts for the majority of cases. A specific pulmonary arterial hypertension group in conjunction with congenital heart disease can be identified that resembles patients with idiopathic pulmonary arterial hypertension. Combined pulmonary arterial hypertension-specific therapies may have contributed to disease stability and favourable survival.

Myocardial adaptation to anemia and red blood cell transfusion in premature infants requiring ventilation support in the 1st postnatal week.

BACKGROUND: Although transfusion practice in very premature infants is becoming more restrictive, little is known about myocardial adaptation to anemia during the 1st postnatal week. OBJECTIVES: To determine the central hemodynamic effects of anemia and red blood cell transfusion in very preterm infants undergoing intensive care. METHODS: Twenty-nine neonates of less than 30 weeks gestational age were treated for respiratory distress syndrome, following a strict protocol. Echocardiographies were performed at the 4th and 6th postnatal days, which corresponded to, respectively, just before and 48 h after an erythrocyte transfusion of 15 ml/kg in the 12 anemic infants. RESULTS: Anemic infants had increased stroke volume [2.1 (1.8-2.3) vs. 1.5 (1.3-1.6) ml/kg] and left ventricular (LV) output [312 (271-345) vs. 206 (177-240) ml/min/kg]. The relationship of the heart rate-corrected velocity of circumferential fiber shortening to LV end-systolic meridional wall stress indicated a higher contractile state in the anemic infants, with a higher y-intercept (p = 0.03) and a steeper slope (p = 0.05) of the regression line than in the nonanemic patients. Posttransfusion, the stroke volume, LV output, shortening fraction, and contractile state decreased to the values observed in the nonanemic infants. CONCLUSIONS: Myocardial contractility was a major component of the circulatory adjustments in the anemic premature infants requiring ventilation support in the early neonatal period. Changes in LV performance associated with anemia were reversed by transfusion with no detrimental effect on right ventricular function, LV preload or the respiratory status of these patients.

Training of aerobic and anaerobic fitness in children with asthma.

OBJECTIVE: To assess the effect of a training protocol on aerobic and anaerobic fitness in children with asthma. STUDY DESIGN: Sixteen boys (mean age: 13 years; range: 10-16 years) with mild-to-moderate asthma participated in a rehabilitation program that included 6 weeks of individualized training on a cycle ergometer. Two groups were randomly formed: the control group (CG, n = 7) and the training group (TG, n = 9), which exercised at an intensity set at the heart rate corresponding to the ventilatory threshold, with 1-minute sprints against the maximal aerobic power (MAP) every 4 minutes. Session duration was 45 minutes, 3 sessions per week. Changes in maximal oxygen uptake (VO(2)max), MAP, short-term peak power (PP), and pulmonary function were assessed. RESULTS: Two patients of the training group did not complete the study. Pulmonary function remained unchanged in both groups. Improvement in both aerobic and anaerobic fitness was significant only in the training group (TG vs CG): VO(2)max +18% +/- 2.1% versus +9% +/- 4.5% (P <.05), MAP +32% +/- 5% versus 12% +/- 7% (P <.05), PP +21% +/- 5.7% versus +8.8% +/- 10% (P <.01). CONCLUSION: Exercise training with high-intensity bouts is well tolerated in children with mild-to-moderate asthma. When included in a global rehabilitation program, this type of training improves both aerobic and anaerobic fitness. Anaerobic activities should be considered in sports rehabilitation programs for children with asthma.