ABNORMALITIES IN CIRCULATING VON-WILLEBRAND-FACTOR AND SURVIVAL IN PULMONARY-HYPERTENSION

BACKGROUND: Changes in circulating von Willebrand factor (vWF) have be en widely used for evaluating the severity of endothelial dysfunction in vascular disorders. In pulmonary hypertension, quantitative and str uctural abnormalities in circulating von Willebrand factor have been i dentified. We therefore hypothesized that these abnormalities could ha ve prognostic implications. PATIENTS AND METHODS: We studied 30 consec utive medically treated patients with primary (n = 11) or secondary pr ecapillary pulmonary hypertension associated with congenital heart dis ease (n = 16) or schistosomiasis (n = 3). Plasma antigenic activity of vWF (vWF:Ag) was measured by electro-immunodiffusion. The relative co ncentration of low molecular weight VWF multimers (vWF:LMW/Total) was determined by Western immunoblotting. Results of initial evaluation we re analyzed at the end of the first and third years of follow-up. RESU LTS: Baseline vWF:Ag activity (P <0.0002) and the VWF: LMW/Total ratio (P <0.005) were higher in patients who died during the first year tha n in survivors. All patients with vWF:Ag activity >250% or a vWF:LMW/T otal ratio >70% died in the first year. All 7 patients with vWF:Ag act ivity <100% were alive at the end of 3 years of follow-up. A vWF:LMW/T otal ratio >68% waste 67% sensitive and 95% specific for 1-year mortal ity, with an overall predictive value of 80%. Both vWF:Ag levels and m ortality were greater in the patients with primary pulmonary hypertens ion than in patients with secondary pulmonary hypertension. CONCLUSION : Patients with pulmonary hypertension who have abnormalities in circu lating vWF have reduced 1-year survival. This might affect decisions s uch as patient assignment to lung transplantation. (C) 1998 by Excerpt a Medica, Inc.