To evaluate the potential efficacy of the combined administration of inhaled nitric oxide and oral beraprost sodium in producing pulmonary vasodilation, we studied 20 patients with pulmonary hypertension during cardiac catheterization. We also evaluated some of the mechanisms of vasodilation under these circumstances by investigating the levels of cyclic GMP and AMP in the pulmonary venous blood. A significant decrease in pulmonary vascular resistance was observed after the administration of nitric oxide (−37 ± 6%, p<0.01), and more intense decrease was observed after the combined administration of nitric oxide and beraprost sodium (−46 ± 6%, p<0.05). In addition, the ratio of pulmonary-to-systemic resistance also decreased to a greater extent with combined administration than with nitric oxide alone (−34 ± 6% vs −42 ± 7%, p<0.05). Conversely, systemic vascular resistance showed no change, neither after loading with nitric oxide nor after combined administration. Although equivalent increases in levels of cyclic GMP were observed after inhalation of nitric and the combined administration (mean 78% vs 65%), greater increases in levels of cyclic AMP were observed with the combined use (mean 15% vs 69%). Combined treatment with nitric oxide and beraprost sodium may prove markedly beneficial in patients with primary and postoperative pulmonary hypertension who do not respond adequately to inhalation of nitric oxide alone or conventional modes of treatment.

There are many congenital malformations of the mitral valve which produce valvar insufficiency. From a surgical point of view, systems based exclusively on anatomic analysis are not always entirely appropriate for assessment of these lesions. With this in mind, Carpentier proposed a functional approach for analysis based upon the motion of the valvar leaflets. From 1969 to 1994, 135 children under the age of 12 (mean age: 5.8 + 3.15 Y, 0.6–12Y) underwent surgery in our department, basing treatment on such analysis. Since motion of the leaflets during the operation is compromised by cardioplegia, and sometimes exposure can be however difficult, preoperative echocardiography was a mandatory part of the diagnostic cascade.

Normal motion of the leaflets was present in 41 patients, with deformation of the annulus in 14, a cleft in 21, and partial agenesis in 6. Prolapse of leaflets was present in 42 patients. Leaflet motion was restricted in 28 patients. These were divided in two groups, one with normal papillary muscles and commissural fusion or short cords. The other with abnormal papillary muscles producing a parachute arrangement in 6 and a hammock valve in 9. Associated lesions were present in 47% of the patients. Conservative surgical procedures following the precepts developed by Carpentier were used in 127 patients. Valvar replacement was necessary in 8 patients. Operative mortality was 4%. Mean follow up was 8.4 ± 5.3 years (1–23Y). Actuarial survival at 5 years was 90 ± 6% and, at this time, was stable. No thromboembolic events occurred after conservative surgery. The reoperation rate was 5% for those undergoing repair (6 patients). We conclude that the functional classification developed by Carpentier is a reliable and robust approach to these complex lesions. Conservative surgery is feasible in most of the cases presenting with congenital mitral valvar insufficiency. Results are stable and reliable. Surgery should be undertaken before the onset of left ventricular deterioration.

Pulmonary arteriovenous malformations are a frequent cause of progressive cyanosis after construction of a cavopulmonary anastomosis. Their formation complicates the management of children with single ventricle physiology after a bidirectional Glenn shunt or the Kawashima procedure. The key role of the liver in this phenomenon is suggested by the observation that providing modifications of the Fontan procedure which permit hepatic venous effluent to reach the pulmonary arterial circulation limit further development of the malformations. In addition, it is known that patients with end-stage hepatic failure develop pulmonary arteriovenous malformations that diminish after liver transplantation. We have begun purification of a factor derived from hepatocyte-conditioned media that is inhibitory for the proliferation of cultured endothelial cells. This substance is heat sensitive, and binds avidly to a copper-containing chromatography column. These clinical observations, and this preliminary experimental work, support the concept that hepatic-derived angiogenic factors may play a role in the development of pulmonary arteriovenous malformations after construction of cavopulmonary anastomoses.

Lesions producing congenital mitral valvar stenosis are complex and often multiple, From 1970 to 1994, 58 patients under 12 years of age (mean 5 ± 3.2 y) underwent surgical treatment for such malformations in our department. In order to provide a clear understanding of the pathology, we used a classification based on anatomy and function. Echocardiography was a major tool of the preoperative investigations. The lesions were classified as follows:

Normal papillary muscles: commissural fusion in 19, excess leaflet tissue in 2, valvar ring in 12, and annular hypolasia in 2.

Abnormal papillary muscles: paachute arrangement in 10 and hammock mitral valve in 13.

Associated malformations were found in 63%, the most common being multiple stenosis in the left heart. Conservative treatment was possible in 54 patients (95%) using the techniques developed by Carpentier. Hospital mortality was 22%, with 95% confident limits between 13 and 36% (13/58). Of the 13 patients with a hammock valve, 6 died in hospital. The overall mean period of follow up was 7.8 + 5 years. No thromboembolic events occured after conservative surgery. Late death occured in 3%. The actuarial survival at 5 years was 64 + 15%. Reoperation was needed for residual mitral valvar stenosis in three patients or insufficiency in one.

In spite of effective techniques to relieve mitral obstruction, 12% of our patients need early or delayed replacement of the valve. The hospital mortality remains high due to the complexity of the lesions, associated with the associated malformations. Echocardiography proved to be extremly helpful for the functional analysis. In order to improve operative results, simple and early valvar repair, even if considered palliative, seems to be appropriate.

Transvenous placement of pacemaker leads is the recommended method for permanent pacemaking in children. We evaluated 11 children with transvenous ventricular pacemaker leads by digital subtraction angiography in order to determine the incidence of venous obstruction. The ages at the implantation ranged from 4.5 to 11.2 years with a mean of 8.05±2.17 and a median of 7.9 years. The interval from implantation to the time of procedure ranged from 12 to 64 months, with a mean of 37.4±19.2 and a median of 45 months. Complete occlusion of the subclavian vein was demonstrated in two patients. We also showed significant stenosis of the venous system in five further patients. Of the 7 patients, 5 had an extensive venous collateral circulation. We did not observe obstruction of the superior caval vein, or superior caval venous syndrome. Although we did not demonstrate this syndrome, we propose future regular evaluation of all our children undergoing transvenous pacemaking. This point may be important when second or third leads are implanted.