title: Acquired von Willebrand syndrome in children with aortic and pulmonary stenosis.
abstract: BACKGROUND
  This prospective study was planned to investigate the frequency and relationship of acquired von Willebrand syndrome (AVWS) with aortic and pulmonary stenosis in patients.
  
  
  METHODS
  A total of 84 children, ranging from two to 18 years of age, were enrolled in this study. Of these, 28 had isolated aortic stenosis, 32 had isolated pulmonary stenosis and 24 were healthy. Children with aortic and pulmonary stenosis associated with other congenital heart diseases were excluded. Children with hypothyroidism, renal or liver disease, malignancy or autoimmune disease were also excluded. Wholeblood count, blood group, factor VIII level, prothrombin time (PT), activated partial thromboplastin time (aPTT), von Willebrand factor antigen (VWF:Ag), ristocetin co-factor (VWF:RCo), and bleeding time using a platelet-function analyser (PFA-100) were performed in all patients. All of the children in the study underwent a detailed physical examination and echocardiographic evaluation.
  
  
  RESULTS
  A history of bleeding was positive in 18% of the aortic stenosis group, 9% of the pulmonary stenosis group, and 4% of the control group. Seven of 60 (12%) patients had laboratory findings that implied a diagnosis of AVWS, and two of these (28%) had a history of bleeding. The frequency of AVWS was 14% in patients with aortic stenosis and 9% in those with pulmonary stenosis.
  
  
  CONCLUSIONS
  AVWS is not rare in stenotic obstructive cardiac diseases. A detailed history of bleeding should be taken from patients with valvular disease. Even if the history is negative, whole blood count, PT and aPTT should be performed. If necessary, PFA-100 closure time and further tests should be planned for the diagnosis of AVWS.
authors.affiliation: Department of Paediatric Cardiology, Çanakkale Onsekiz Mart University, Çanakkale, Turkey.
authors.forename: Fatih Köksal
authors.initials: FK
authors.lastname: Binnetoğlu
authors.affiliation: Department of Paediatric Cardiology, Kocaeli University Medical Faculty, Kocaeli, Turkey.
authors.forename: Kadir
authors.initials: K
authors.lastname: Babaoğlu
authors.affiliation: Department of Paediatrics, Karabük State Hospital, Karabük, Turkey.
authors.forename: Şayegan Güven
authors.initials: ŞG
authors.lastname: Filiz
authors.affiliation: Department of Paediatric Haematology, Kocaeli University Medical Faculty, Kocaeli, Turkey.
authors.forename: Emine
authors.initials: E
authors.lastname: Zengin
authors.affiliation: Department of Paediatric Cardiology, Kocaeli Derince Education and Research Hospital, Kocaeli Turkey.
authors.forename: Gürkan
authors.initials: G
authors.lastname: Altun
authors.affiliation: Department of Paediatric Haematology, Cumhuriyet University Medical Faculty, Sivas, Turkey.
authors.forename: Suar Çakı
authors.initials: SÇ
authors.lastname: Kılıç
authors.affiliation: Department of Paediatric Haematology, Kocaeli University Medical Faculty, Kocaeli, Turkey.
authors.forename: Nazan
authors.initials: N
authors.lastname: Sarper
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001024:Aortic Valve Stenosis / Q000150:complications* / Q000175:diagnosis; D001777:Blood Coagulation; D001780:Blood Coagulation Tests; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D010979:Platelet Function Tests; D011379:Prognosis; D011446:Prospective Studies; D011666:Pulmonary Valve Stenosis / Q000150:complications* / Q000175:diagnosis; D014421:Turkey / Q000453:epidemiology; D014842:von Willebrand Diseases / Q000097:blood / Q000150:complications* / Q000175:diagnosis