Procoagulatory changes induced by head-up tilt test in patients with syncope: observational study

Thrombosis Journal

Research

Karin Strandberg¹  Artur Fedorowski²  Nazim Isma³  Viktor Hamrefors⁴  Richard Sutton⁵ 

[1] Centre for Thrombosis and Haemostasis, Skåne University Hospital, SE 205-02, Malmö, Sweden;Department of Clinical Sciences Malmö, Lund University, SE 205-02, Malmö, Sweden;Department of Cardiology, Skåne University Hospital, Inga Marie Nilssons gata 46, SE 205-02, Malmö, Sweden;Department of Clinical Sciences Malmö, Lund University, SE 205-02, Malmö, Sweden;Department of Cardiology, Skåne University Hospital, SE 221-85, Lund, Sweden;Department of Clinical Sciences Malmö, Lund University, SE 205-02, Malmö, Sweden;Department of Internal Medicine, Skåne University Hospital, SE 205-02, Malmö, Sweden;Department of Medical Imaging and Physiology, Skåne University Hospital, SE 205-02, Malmö, Sweden;National Heart and Lung Institute, Imperial College, Hammersmith Hospital Campus, Ducane Road, W12 0NN, London, UK;

关键词: Orthostatic stress;    Hypercoagulability;    Coagulation factors;    Partial thromboplastin time;    Fibrinogen;    von Willebrand factor;   

DOI  :  10.1186/s12959-017-0139-z

 received in 2017-03-30, accepted in 2017-06-13,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundOrthostatic hypercoagulability is proposed as a mechanism promoting cardiovascular and thromboembolic events after awakening and during prolonged orthostasis.We evaluated early changes in coagulation biomarkers induced by tilt testing among patients investigated for suspected syncope, aiming to test the hypothesis that orthostatic challenge evokes procoagulatory changes to a different degree according to diagnosis.MethodsOne-hundred-and-seventy-eight consecutive patients (age, 51 ± 21 years; 46% men) were analysed. Blood samples were collected during supine rest and after 3 min of 70° head-up tilt test (HUT) for determination of fibrinogen, von Willebrand factor antigen (VWF:Ag) and activity (VWF:GP1bA), factor VIII (FVIII:C), lupus anticoagulant (LA1), functional APC-resistance, and activated prothrombin time (APTT) with and without activated protein C (C+/−). Analyses were stratified according to age, sex and diagnosis.ResultsAfter 3 min in the upright position, VWF:Ag (1.28 ± 0.55 vs. 1.22 ± 0.54; p < 0.001) and fibrinogen (2.84 ± 0.60 vs. 2.75 ± 0.60, p < 0.001) increased, whereas APTT/C+/− (75.1 ± 18.8 vs. 84.3 ± 19.6 s; p < 0.001, and 30.8 ± 3.7 vs. 32.1 ± 3.8 s; p < 0.001, respectively) and APC-resistance (2.42 ± 0.43 vs. 2.60 ± 0.41, p < 0.001) decreased compared with supine values. Significant changes in fibrinogen were restricted to women (p < 0.001) who also had lower LA1 during HUT (p = 0.007), indicating increased coagulability. Diagnosis vasovagal syncope was associated with less increase in VWF:Ag during HUT compared to other diagnoses (0.01 ± 0.16 vs. 0.09 ± 0.17; p = 0.004).ConclusionsProcoagulatory changes in haemostatic plasma components are observed early during orthostasis in patients with history of syncope, irrespective of syncope aetiology. These findings may contribute to the understanding of orthostatic hypercoagulability and chronobiology of cardiovascular disease.

【 授权许可】

CC BY   
© The Author(s). 2017