[Pulmonary hypertension and pulmonary vascular disease in congenital heart defects].

Pulmonary vascular disease (PVD) is a serious complication of several congenital heart defects (CHD). The post-tricuspid heart lesions, such as AVSD, VSD, PDA, TGA with VSD, Ao-pulmonary window, Truncus arteriosus, DORV and DILV (univentricular heart) with a high pressure and increased flow in the pulmonary circulation are earlier and more often the cause of PVD than such pretricuspid shunts as ASD or TAPVD. The pathogenesis of PVD is only partially known. The endothelial cell of the pre- and intraacinar arteries releases substances (eicosanoids and mitogens) which cause functional and structural changes in the wall of arteriols and precapillary arteries: media hypertrophy, intima proliferation, obliterations, and necroses. The number and size of small arteries is reduced. Advanced changes are irreversible. Subtle diagnostic tools are necessary to evaluate the clinical, hemodynamic and morphologic status of the pulmonary circulation. Clinical signs, ECG, echocardiogram, x-ray of the chest, cardiac catheterization and special angiograms of the lung vessels have to be performed and their results have to be viewed in a synopsis. The type of tapering of the small arteries in the wedge-angio, the transit time of contrast media in the digital function angio, and changes of pressure and flow under test conditions give further information. Biopsy and histologic studies are difficult and not without risk. Treatment means prevention of advanced changes of PVD. Earlier correction of operable defects, banding of the pulmonary artery in complex heart lesions can avoid the development of PVD. A potent dilator of the small pulmonary arteries, applicable orally and over a long time, is not available at present.(ABSTRACT TRUNCATED AT 250 WORDS)