Age-related changes among 25 patients with congenital cardiac left-to-right shunts and irreversible plexogenic pulmonary arteriopathy

Abstract

Some patients with congenital heart disease and irreversible plexogenic pulmonary arteriopathy survive into adulthood. The purpose of this study was to compare histopathological and antigen expression patterns in adults and children with congenital heart disease and plexogenic pulmonary arteriopathy. Autopsy/explant lung tissues from 25 patients with congenital heart disease and plexogenic pulmonary arteriopathy were reviewed for 24 histopathological parameters associated with plexogenic pulmonary arteriopathy, including the prevalence and character of plexiform lesions. Immunohistochemistry using antibodies against CD31, C-kit, smooth muscle actin, CD68, and Fli-1 was performed to evaluate plexiform lesions. Group 1 consisted of 14 patients aged <20 years, and Group 2 included 11 patients aged >or=20 years (range, 20-69 years). Cellular plexiform lesions trended toward greater prevalence in Group 1 than in Group 2 (P=.081), whereas involuted plexiform lesions more frequently affected Group 2 than Group 1 (P=.0037). In addition, recent platelet-fibrin thrombi within plexiform lesions occurred more often in Group 1 than in Group 2 (P=.0419). Intimal proliferation/fibrosis of elastic arteries and pulmonary vein dilation were more common in Group 2 (P=.0172 and P=.0048, respectively). CD31 and C-kit staining in non-lumen-lining cells of plexiform lesions was more frequent in Group 2 than in Group 1 (P=.0858 and P=.0173, respectively). No statistically significant differences in expression patterns between cellular and involuted plexiform lesions existed. Among patients with congenital heart disease and plexogenic pulmonary arteriopathy, histopathological differences were observed between those surviving into adulthood and those dying in childhood/adolescence. Plexiform lesions in adults undergo remodeling from a cellular morphology to an involuted morphology. It is unclear whether this simply represents the natural progression of plexiform lesions or also confers a survival advantage.