Cardiovascular Journal of Africa: Vol 27 No 4 (July/August 2016)

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 4, July/August 2016

222

AFRICA

Acquired von Willebrand syndrome in children with aortic

and pulmonary stenosis

Fatih Köksal Binneto

lu, Kadir Babao

lu,

ayegan Güven Filiz, Emine Zengin, Gürkan Altun, Suar Çakı

Kılıç, Nazan Sarper

Abstract

Introduction:

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, malig-

nancy or autoimmune disease were also excluded. Whole-

blood 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 examina-

tion 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.

Conclusion:

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.

Keywords:

aortic stenosis, children, pulmonary stenosis, von

Willebrand

Submitted 21/3/15, accepted 7/12/15

Cardiovasc J Afr

2016;

: 222–227

www.cvja.co.za

DOI: 10.5830/CVJA-2015-093

Acquired von Willebrand syndrome (AVWS) is a rare clinical

condition characterised by prolonged bleeding time and

decreased levels of factor VIII and von Willebrand factor, as in

congenital von Willebrand disease (VWD). It was first defined

by Simone

et al

. in a seven-year-old boy with systemic lupus

erythematosus.

The actual prevalence of AVWS is uncertain.

From 1968 to 1999, a total of 266 cases were reported. The

International Society of Thrombosis and Haemostasis reported

a retrospective analysis of 186 cases in 2000.

AVWS is usually associated with underlying diseases such

as lymphoproliferative disorders (48%), cardiovascular diseases

(21%), myeloproliferative disorders (15%), other neoplasms (5%)

and autoimmune diseases (2%).

In rare cases, AVWS is also

associated with hypothyroidism, uraemia and certain drugs, such

as valproic acid and ciprofloxacin.

A few studies have reported on the association between

AVWS and aortic stenosis in adults, but there are not enough

studies reporting on the relationship between AVWS and right

ventricular outflow obstruction. In patients with aortic stenosis,

there is a loss of high-molecular-weight multimers, which are

active in coagulation, due to increased shear stress. This situation

can cause bleeding problems after menstruation, circumcision,

dental extraction and congenital heart disease surgery.

No other coagulation tests are routinely used in people with

heart disease, because AVWS has been identified in only a small

number of patients. Therefore, it is of importance to identify

AVWS in children with congenital heart diseases.

1,3-5

In this

study, we aimed to evaluate AVWS in children with aortic and

pulmonary stenosis, and their clinical consequences.

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

Department of Paediatric Cardiology, Çanakkale Onsekiz

Mart University, Çanakkale, Turkey

Fatih Köksal Binneto

lu, MD,

koksaldr@yahoo.com

Department of Paediatric Cardiology, Kocaeli University

Medical Faculty, Kocaeli, Turkey

Kadir Babao

lu, MD

Department of Paediatrics, Karabük State Hospital,

Karabük, Turkey

ayegan Güven Filiz, MD

Department of Paediatric Haematology, Kocaeli University

Medical Faculty, Kocaeli, Turkey

Emine Zengin, MD

Nazan Sarper, MD

Department of Paediatric Cardiology, Kocaeli Derince

Education and Research Hospital, Kocaeli Turkey

Gürkan Altun, MD

Department of Paediatric Haematology, Cumhuriyet

University Medical Faculty, Sivas, Turkey

Suar Çakı Kılıç, MD