Clinical Effects of Syncope on Disease Severity and Adverse Outcomes in Children with Idiopathic and Heritable Pulmonary Arterial Hypertension.

Syncope is more common in children with idiopathic pulmonary arterial hypertension (PAH) than in adults with PAH. Although syncope is associated with a poor prognosis in adult PAH, the clinical effects of syncopal events on disease severity and outcome in children have not been carefully investigated. This study assessed the prevalence of syncope in pediatric PAH and examined its clinical, hemodynamic, and prognostic importance. This retrospective study assessed clinical data, including syncope status, from 78 children (37 girls) with idiopathic and heritable PAH (median age at diagnosis, 11 years). Patients were classified as syncopal or non-syncopal, and clinical data from the two groups were compared. The primary outcome was a composite of lung transplantation and cardiac mortality. Overall, 31 (38%) children had a history of syncope at presentation. Median age at diagnosis, sex ratio, brain natriuretic peptide level, and 6-min walk distance at diagnosis did not differ between groups. The hemodynamic parameters of initial right heart catheterization were similar between the syncope and non-syncope group (mean pulmonary artery pressure, 67 versus 71 mm Hg; cardiac index, 2.9 versus 2.9 l/min/m2, respectively). There was not significantly difference in event-free survival rate between two groups. Although syncopal events are common in children with PAH, our findings suggest that syncope may not be correlated with disease severity or outcome in pediatric PAH.

Correction to: Clinical Effects of Syncope on Disease Severity and Adverse Outcomes in Children with Idiopathic and Heritable Pulmonary Arterial Hypertension.

The original version of this article unfortunately contained a mistake in the author name. The co-author name should be Hiroyuki Matsuura instead of Horoyuki Matsuura. The original article has been corrected.

Clinical Impact of Main Pulmonary Artery Dilatation on Outcome in Pediatric Idiopathic and Heritable Pulmonary Arterial Hypertension.

BACKGROUND: Few studies have investigated the clinical impact of pulmonary artery (PA) dilatation on outcomes in pediatric pulmonary arterial hypertension (PAH).Methods and Results:This study investigated the clinical outcomes of idiopathic or heritable PAH in 66 children aged <18 years at diagnosis. Main PA/thorax (MPA/T) ratio was measured on chest radiography in PAH patients. Patients were divided into 2 groups based on MPA/T ratio, and compared with a control group of 166 age- and gender-matched healthy children. Group A had higher MPA/T ratio than normal, and group B had normal MPA/T ratio. Composite outcomes included cardiac death, lung transplantation, and hospitalization due to heart failure. Group A consisted of 27 patients and group B, 39 patients. At diagnosis, group A had significantly higher brain natriuretic peptide (BNP), cardiothoracic ratio, PA pressure, and pulmonary vascular resistance index compared with group B. The number of patients with New York Heart Association (NYHA) functional class III and IV was significantly higher in group A than in group B. Cumulative event-free survival rate was significantly lower in group A. CONCLUSIONS: MPA dilatation correlated with BNP, NYHA functional class, and hemodynamics with regard to disease severity, and may be a potential prognostic factor in pediatric idiopathic and heritable PAH.

Pulmonary Arterial Capacitance Index Is a Strong Predictor for Adverse Outcome in Children with Idiopathic and Heritable Pulmonary Arterial Hypertension.

OBJECTIVES: To evaluate the clinical utility of pulmonary artery capacitance index (PACi) in the assessment of disease severity and prognostic value in children with idiopathic and heritable pulmonary arterial hypertension (PAH). STUDY DESIGN: PACi is defined as the ratio of stroke volume index over pulmonary pulse pressure. A retrospective study was performed to compare PACi, brain natriuretic peptide (BNP), 6-minute walk distance, New York Heart association (NYHA) functional class, and adverse outcomes (hospitalization due to heart failure, lung transplantation, and cardiac mortality) in 72 Japanese children (10 ± 3.6 years) with idiopathic and heritable PAH. RESULTS: PACi had significant correlations with pulmonary vascular resistance index (r =-0.73, P < .0001), BNP levels (r = -0.40, P = .0008), and 6-minute walk distance (r = 0.57, P < .05). Statistically significant differences in PACi were observed between NYHA functional class II vs combined III and IV (median; 1.1 vs 0.6 mL/mm Hg/m2, respectively, P < .05). There were 25 of 72 (35%) children who had an adverse event including initiation of hospitalization due to heart failure, lung transplantation, and death. Cumulative event-free survival rate was significantly lower when PACi was <0.85 mL/mm Hg/m2 (log-rank test, P < .0001). CONCLUSIONS: PACi correlated with BNP and NYHA functional class and may serve as a strong prognostic marker in children with idiopathic and heritable PAH.

Coronary artery outcomes among children with Kawasaki disease in the United States and Japan.

OBJECTIVE: It has been claimed that the aneurysm rate for Kawasaki disease (KD) patients in Japan is lower than in the U.S. However it has been difficult to compare coronary artery (CA) outcomes between the two countries because of different definitions for CA abnormalities. Therefore, we compared CA internal diameters between Japanese and U.S. KD patients using standard definitions and methods. STUDY DESIGN: We retrospectively reviewed CA outcomes in 1082 KD patients from 2 centers in the U.S. and 3 centers in Japan and compared Z-max scores (maximum internal diameter for the left anterior descending or right coronary artery expressed as standard deviation units from the mean (Z-score) normalized for body surface area) obtained within 12 weeks after onset and calculated using two different regression equations from Canada (Dallaire) and Japan (Fuse). We defined a Z-max of < 2.5 as normal and a Z-max of ≥ 10 as giant aneurysm. RESULT: The median Z-max for the U.S. and Japanese subjects was 1.9 and 2.3 SD units, respectively (p < 0.001). There was no significant difference in rates of patients with Z-max ≥ 5.0 between the countries. In a multivariable model adjusting for age, sex, and treatment response, being Japanese was still associated with a higher Z-max score. CONCLUSION: Previously reported differences in aneurysm rates between Japan and the U.S. likely resulted from use of different definitions and nomenclature. Adoption of Z-scores as a standard for reporting CA internal diameters will allow meaningful comparisons among different countries and will facilitate international, collaborative clinical trials.

A 3-year-old girl with Graves' disease with hypoglycemia following transient adrenal hyporesponsiveness.

A 3-year-old girl with Graves' disease developed a generalized convulsion as a result of hypoglycemia (25 mg/dL). At the time of the hypoglycemic seizure, her plasma adrenocorticotropin (ACTH) level (1460 pg/mL) was extremely high, but her serum cortisol level (28.4 microg/dL) was relatively low given the severe stress. The cortisol-releasing hormone (CRH) provocation test done after thyroid function had improved revealed normal ACTH and cortisol responses. Since there was no other cause of hypoglycemia, such as hyperinsulinemia, long-term starvation, suddenly advanced emaciation, or prolonged fasting, it was suspected that the transient adrenal hyporesponsiveness was the main cause of hypoglycemia.

Autoimmune thyroid disease in children and adolescents with idiopathic pulmonary arterial hypertension.

BACKGROUND: Previous studies have reported a high prevalence of autoimmune thyroid disease (AITD) in adult patients with pulmonary arterial hypertension (PAH). The aim of this retrospective study was to determine the prevalence of AITD in children and adolescents with idiopathic PAH (IPAH). METHODS AND RESULTS: The study group included 16 patients who had been diagnosed as having idiopathic PAH when they were younger than 15 years old; all were younger than 20 years of age. Thyroid function and antithyroid antibody levels were examined regularly at 6-12-month intervals and when there were clinical signs of thyroid dysfunction. In total, 7 patients (44%) had AITD; 2 patients developed Graves' disease, 2 developed silent thyroiditis, and 3 had antithyroid antibodies with euthyroidism. The duration after PAH onset and the prostacyclin (PGI(2)) treatment period were significantly longer in patients with AITD (7.6+/-2.1 and 7.4+/-2.3 years, respectively) than in patients without AITD (5.0+/-1.1 and 4.8+/-1.2 years, respectively; P<0.01 and P<0.05). CONCLUSIONS: The prevalence of AITD is high in children and adolescents with IPAH, so evaluation of thyroid function is important to prevent deterioration of right heart failure.