Multiple pulmonary arteriovenous fistulas in childhood.

Three cases of multiple pulmonary arteriovenous fistulas are described in children who presented at five months, two and nine years of age. Mass spectrometry was used to measure pulmonary blood flow and, in two cases, the intrapulmonary right-to-left shunt. The shunt fractions were 51% and 35%, with no significant change on breathing 100% oxygen. In one case, effective pulmonary blood flow was measured during cardiac catheterisation by the argon-freon rebreathing method and agreed closely with that found from the Fick, principle with measured oxygen consumption. Treatment consisted of surgical ligation of a lower lobe pulmonary artery in the youngest child, balloon embolisation in the second, and initial surgical oversewing of a single large fistula followed twenty months later by steel coil embolisation in the third. The last and oldest child is well and no longer cyanosed. The first two children died seven months after treatment with evidence of progression of their pulmonary arteriovenous fistulas. The first of these, who also had an atrial septal defect and discordant thoraco-abdominal arrangement, died of heart failure. Autopsies on both children confirmed extensive involvement of both lungs by arteriovenous fistulas. In one case who had a diffuse, telangiectatic form of pulmonary arteriovenous fistulas, microscopic serial reconstructions of lung tissue revealed that anastomoses occurred between arteries accompanying terminal bronchioles and intra-acinar arteries and adjacent veins. Occlusion of the pulmonary arteries supplying the fistulas led to extensive fibrosis within them, and was associated with enlargement of the corresponding bronchial arterial circulation.

Capillary haemangioma presenting as a lung pseudocyst.

A girl who developed a lung cyst at 24 hours of age during gentle ventilation for respiratory distress syndrome is reported. Instead of resolving as expected of a pseudocyst it continued to expand. Resection at 1 year of age showed a cyst entirely surrounded by capillary haemangioma. Aspiration of this cyst would have been dangerous.

Effective pulmonary blood flow in normal children at rest.

Effective pulmonary blood flow was measured with a soluble inert gas uptake method (10% argon, 3.5% freon-22, 35% oxygen, balance nitrogen) in 98 apparently healthy children aged 5-14 years. None had any evidence of cardiorespiratory disease and all had normal values for absolute and dynamic lung volumes and transfer factor for carbon monoxide. Values of blood flow measured by a rebreathing method correlated reasonably closely with height, weight, body surface area, and lung volumes, and to a lesser extent with hand and foot size. The mean (SD) effective pulmonary blood flow index was 2.7 (0.31) 1 min-1 m-2. Small children found a single breath method of measuring flow more difficult to perform and the results were more variable.

Variations in clinical presentation of Fallot's tetralogy in infancy. Angiographic and pathogenetic implications.

Striking variability has been observed in the presenting features in infancy of patients subsequently shown to have tetralogy of Fallot. Some patients presented with severe cyanosis in the neonatal period while others had a systolic murmur and cyanosis only on crying. In these latter patients cyanosis became present at rest over the subsequent months. Yet others presented with episodic attacks of unconsciousness, and a final group presented with dyspnoea and heart failure, accompanying a left-to-right shunt. Angiography demonstrates corresponding variations in the anatomy of the ventricular outflow tracts. In the severely cyanosed patients, the conus septum was deviated so as to obstruct the pulmonary outflow tract, and was best visualized in the lateral projection. In the patients with increasing cyanosis or episodic attacks of unconsciousness, the conus septum again obstructed the pulmonary infundibulum, but was obliquely orientated, not being seen clearly on either lateral or frontal projections. The episodic attacks were considered to be related to infundibular spasm, as previously shown to occur in Fallot's tetralogy. In contrast, increasing cyanosis was believed to be related to hypertrophy of infundibular musculature. In the patients with an initial left-to-right shunt, the arteries were orientated side-by-side so that the conus septum was observed in the frontal projection. Again, subsequent cyanosis was related to ventricular hypertrophy producing outflow tract obstruction. These findings are interpreted in the setting of a recent study, indicating that Fallot's tetralogy is produced by rotation of the embryonic conus together with sinistro-anterior deviation of the conus septum.

Exercise ability after Mustard's operation.

Twenty children who were well six to 12 years after undergoing Mustard's operation for transposition of the great arteries were studied. Each child performed a graded maximal treadmill test with measurements of gas exchange and oxygen saturation, and had electrocardiography carried out. Nineteen were also catheterised, and oxygen consumption was measured so that pulmonary and systemic flow could be calculated. Compared with 20 age and size matched controls, seven of the patients had normal exercise tolerance (as judged by a maximal oxygen consumption of greater than 40 ml/kg/min), 10 showed a moderate reduction (30-39 ml/kg/min), and three were more seriously limited. None of the patients with normal exercise tolerance had obstruction of venous return but six of those with mild impairment of exercise ability had partial or complete obstruction of one or both of the vena cavas. More severe limitation was associated with pulmonary vascular disease and fixed ventricular outflow tract obstruction. Formal exercise testing of apparently well children who have undergone Mustard's operation identifies those with haemodynamic abnormalities that may require intervention.

Effect of long term oxygen treatment at home in children with pulmonary vascular disease.

Inhalation of 100% oxygen by nine children with pulmonary vascular disease increased pulmonary blood flow measured at cardiac catheterisation; there was no significant change in pulmonary artery pressure. Fifteen children with pulmonary vascular disease that was severe enough to preclude corrective cardiac operation were studied to determine the effect of long term oxygen treatment on pulmonary vascular disease. Nine received long term domiciliary oxygen for a minimum of twelve hours a day for up to five years. Though the untreated group closely resembled the treated group their survival was significantly less good. All nine treated children are alive whereas five of the six children who did not receive oxygen have died.