Thrombus - 2003

Mechanical prostheses and anticoagulation
Pushpinder Sidhu and Hugh O’Kane
pp 1-4
Although the first mechanical valve was implanted in the descending aorta for a patient with aortic regurgitation, orthoptic mechanical heart-valve replacement surgery became possible with the advent of cardiopulmonary bypass in the mid-1950s Harken was credited with the first aortic valve replacement (AVR) in 1960, and Starr with the first mitral valve replacement (MVR), also in 1960. Both used caged ball valves. Shortly after this, caged disc valves were developed. In its early stages thromboembolism was a common feature – reported at up to 4% per year – and warfarin was the chief anticoagulant.

Comment: Customised warfarin dosage
Peter Rose
pp 3-3
Clinicians have struggled to produce a safe and user-friendly regimen for the commencement of oral anticoagulation. Initiation of warfarin therapy remains a continuing challenge as many clinicians continue to use loading dose regimens stored in the cerebral recesses from medical school days, many of which are distinctly unsafe. The problem is compounded by the ever increasing need to rapidly anticoagulate patients and minimise any delay in hospital discharge. The practice, therefore, of giving warfarin in high doses; for example, 10, 10 and 5 mg for the first three days in the expectation that the international normalised ratio (INR) will be fine on Day 4 is dangerous; in particular, because the risk of serious haemorrhage is greatest in the first three weeks of oral anticoagulant treatment.

Anticoagulation in palliative care
Carina Saxby
pp 5-6
Venous thromboembolism (VTE) is common in advanced malignancy. In such cases anticoagulation is hazardous and less effective. Patients with advanced cancer may already be taking multiple medications so there is an increased risk of bleeding.

Congenital atresia of the inferior vena cava and deep vein thrombosis
Myles Bradbury
pp 7-8
The aetiology of deep vein thrombosis (DVT) is multifactorial, involving an interaction between congenital and acquired factors. Research into the causation of acquired factors has focused on both inducing a hypercoagulable state and promoting venous stasis – environmentally (immobility/postoperative) and structurally (mass effect). In contrast, research into congenital factors focuses mainly on coagulation abnormalities promoting a hypercoagulable state. However, congenital structure abnormalities can promote venous stasis leading to thrombosis, but is this an extremely rare finding that doesn’t warrant being implemented onto care pathways screening for causes of DVT?

Anticoagulation and haemodialysis
RM Higgins and MVegad
pp 9-11
Dialysis is a treatment whereby waste and excess fluid is removed from the body. In haemodialysis, blood is removed from circulation at a rate of about 200 ml per minute and is passed through a blood pump and an artificial kidney in order to clean it (the artificial kidney has a surface area of up to 2 m²). The membrane within the artificial kidney activates complement, neutrophils and the coagulation cascade.

Thrombus was previously supported by Bayer from 2014 to 2016, by Boehringer Ingelheim from 2009 to 2013, by sanofi-aventis from 2007 to 2008 and by Leo Pharma from 1998 to 2006.

The data, opinions and statements appearing in the articles herein are those of the contributor(s) concerned; they are not necessarily endorsed by the sponsor, publisher, Editor or Editorial Board. Accordingly the sponsor, publisher, Editor and Editorial Board and their respective employees, officers and agents accept no liability for the consequences of any such inaccurate or misleading data, opinion or statement.

The title Thrombus is the property of Hayward Medical Publishing and PMGroup Worldwide Ltd and, together with the content, is bound by copyright. Copyright © 2019 PMGroup Worldwide Ltd. All rights reserved. The information contained on the site may not be reproduced, distributed or published, in whole or in part, in any form without the permission of the publishers. All correspondence should be addressed to: admin@hayward.co.uk

ISSN 1369-8117 (Print) ISSN 2045-7855 (Online)