Unusual form of coarctation of the distal thoracic aorta.

We report the case of a 3-month-old girl with a rare form of coarctation involving the lower descending thoracic aorta. Because of clinical findings of congestive heart failure and hypertension, early repair was recommended. Surgical intervention in young patients with this unusual localization presents a complex challenge. Aortic reconstruction was carried out by patching the stenotic segment with autologous arterial tissue. Three years after the repair, there is no evidence of recoarctation or aneurysmal dilation.

Factors affecting left ventricular mass in childhood: the Muscatine Study.

OBJECTIVE: To examine the contribution of age, body size, and blood pressure to left ventricular mass (LVM) in childhood and develop a population-based reference of normative LVM data. METHODS: Age, sex, height, weight, and auscultatory systolic and diastolic blood pressures were measured and an echocardiogram was performed to estimate LVM in 904 normal children, aged 6 to 16 years, in Muscatine, IA. Pearson product-moment correlation coefficients were determined to describe the degree of linear association between LVM and age, body size, and blood pressure. Age-sex-, weight-sex-, and height-sex-specific Z scores were determined for LVM, age, weight, height, and blood pressure. Sex-specific LVM prediction equations were derived using weighted-least-squares regression analysis. RESULTS: A strong positive linear association of LVM with age, weight, height, Quetelet index, and systolic and diastolic blood pressure was demonstrated. Z scores for eight different LVM quintile patterns revealed that age, height, weight, and blood pressure each exert an independent influence on LVM in children. Sex-specific predicted M-mode LVM and upper limits of the 90% prediction intervals based on age and height are presented. CONCLUSION: Since age, height, weight, and blood pressure may each exert an independent influence on LVM in children, each factor must be considered when interpreting LVM in childhood. While age, sex, and height are unalterable, both weight and blood pressure can be modified. Thus the pathologic contribution of excess weight and blood pressure ought not be masked by statistical adjustments in reference values for LVM. Sex-specific values of LVM and the 90% and 95% prediction intervals of LVM that do not factor out the effects of obesity or blood pressure are presented. These provide the upper-limit reference values of LVM for the evaluation of children in whom increased LVM is suspected.

Indomethacin compromises hemodynamics during positive-pressure ventilation, independently of prostanoids.

We examined whether prostanoids contribute to the impaired cardiac function and decrease in regional blood flow induced by increasing mean airway pressure. Using microspheres, we measured cardiac output and major organ blood flow and assayed prostaglandin E2, 6-ketoprostaglandin F1 alpha, and thromboxane B2 in blood at mean airway pressures of 5-25 cmH2O in mechanically ventilated newborn piglets treated with ibuprofen (40 mg/kg, n = 6), indomethacin (0.3 mg/kg, n = 6), or vehicle (n = 6). Blood gases and pH were stable throughout the experiments. Prostanoid levels remained constant with increasing mean airway pressure in vehicle-treated pigs and were unchanged by indomethacin. However, ibuprofen decreased the prostanoid levels at all mean airway pressures studied (P < 0.01). As ventilatory pressure was progressively increased, cardiac output decreased gradually and similarly by 42-45% (P < 0.05) in all groups. At the highest mean airway pressure, blood flow decreased to the kidneys by 37-57%, to the ileum by 58-74%, and to the colon by 53-71% (P < 0.05) in all groups. Cerebral blood flow remained constant at all ventilatory pressures regardless of the treatment. There was no difference in cardiac output and regional hemodynamics between ibuprofen- and vehicle-treated animals. However, after indomethacin, ileal blood flow at the higher ventilatory pressures was 41-46% lower and cerebral blood flow at all mean airway pressures was 14-25% lower than after the other treatments (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)