Lopes A A, Maeda N Y, Bydlowski S P
Heart Institute and Department of Hematology, University of São Paulo School of Medicine, Fundação Pró-Sangue Hemocentro de São Paulo, Brazil.
Am J Med. 1998 Jul;105(1):21-6. doi: 10.1016/s0002-9343(98)00138-7.
Changes in circulating von Willebrand factor (vWF) have been widely used for evaluating the severity of endothelial dysfunction in vascular disorders. In pulmonary hypertension, quantitative and structural abnormalities in circulating von Willebrand factor have been identified. We therefore hypothesized that these abnormalities could have prognostic implications.
We studied 30 consecutive medically treated patients with primary (n = 11) or secondary precapillary pulmonary hypertension associated with congenital heart disease (n = 16) or schistosomiasis (n = 3). Plasma antigenic activity of vWF (vWF:Ag) was measured by electroimmunodiffusion. The relative concentration of low molecular weight vWF multimers (vWF:LMW/Total) was determined by Western immunoblotting. Results of initial evaluation were analyzed at the end of the first and third years of follow-up.
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 than in survivors. All patients with vWF:Ag activity >250% or a vWF:LMW/Total ratio >70% died in the first year. All 7 patients with vWF:Ag activity <100% were alive at the end of 3 years of follow-up. A vWF:LMW/Total ratio >68% was 67% sensitive and 95% specific for 1-year mortality, with an overall predictive value of 80%. Both vWF:Ag levels and mortality were greater in the patients with primary pulmonary hypertension than in patients with secondary pulmonary hypertension.
Patients with pulmonary hypertension who have abnormalities in circulating vWF have reduced 1-year survival. This might affect decisions such as patient assignment to lung transplantation.
循环血管性血友病因子（vWF）的变化已被广泛用于评估血管疾病中内皮功能障碍的严重程度。在肺动脉高压中，已发现循环血管性血友病因子存在定量和结构异常。因此，我们推测这些异常可能具有预后意义。
我们连续研究了30例接受药物治疗的患者，其中原发性肺动脉高压患者11例，与先天性心脏病相关的继发性毛细血管前肺动脉高压患者16例，血吸虫病相关的继发性毛细血管前肺动脉高压患者3例。采用电免疫扩散法测定vWF的血浆抗原活性（vWF:Ag）。通过Western免疫印迹法测定低分子量vWF多聚体的相对浓度（vWF:LMW/Total）。在随访的第一年和第三年末分析初始评估结果。
第一年死亡患者的基线vWF:Ag活性（P<0.0002）和vWF:LMW/Total比值（P<0.005）高于存活患者。所有vWF:Ag活性>250%或vWF:LMW/Total比值>70%的患者在第一年死亡。所有7例vWF:Ag活性<100%的患者在随访3年末均存活。vWF:LMW/Total比值>68%对1年死亡率的敏感性为67%，特异性为95%，总体预测价值为80%。原发性肺动脉高压患者的vWF:Ag水平和死亡率均高于继发性肺动脉高压患者。
循环vWF异常的肺动脉高压患者1年生存率降低。这可能会影响诸如患者是否适合肺移植之类的决策。
