Safety indicators confirmed for common treatment of heart defect

July 3, 2012

A new study by medical scientists coordinated from the University of Manchester has for the first time used patients' results to establish that "safety indicators" for people taking anticoagulant drugs to regulate a common heart condition are correct.

More than 760,000 patients in the UK have atrial fibrillation (AF), a defect that causes an irregular heart rate. It is also known to increase the risk and severity of stroke.

The main treatment used to regulate the condition is an anticoagulant drug called which prevents the blood from forming clots so easily. This treatment also lowers the risk of a stroke by about two thirds.

The recommendation to use anticoagulation for patients with AF was circulated to all NHS hospitals and practices last year in a Commissioning Safety Document.

However, there are risks associated with the drug as too little anticoagulation results in thrombosis but too much can result in haemorrhage. Both can be fatal. Patients therefore require frequent monitoring and dose adjustments.

Part of monitoring is measuring a patients' international normalized ratio (INR). In healthy people, the INR is about 1.0. For patients on anticoagulants, the INR typically should be between 2.0 and 3.0. However there had been no large scale studies to establish the danger INR level in patients with AF.

Medical scientists working with the European Action on Anticoagulation which is organised from the University of Manchester tested 5839 patients with AF. The INR for each case was monitored by blood tests which were independently assessed. Any clinical events, such as bleeding or , were also monitored and matched to the patient's INR reading.

The study found that in patients starting to take who had a bleeding episode 9.5% had at least one INR result that was greater than 5.0. This was significantly higher than in the 4.6% of patients who had a bleeding episode but did not develop an INR greater than 5.0.

In the first two months of treatment, bleeding occurred in 11.0% of patients who had at least one incidence of an INR greater than 5.0. Whereas the rate in patients who never recorded an INR greater than 5.0 was only 5%.

Professor Leon Poller, the Project Leader of the European Action on Anticoagulation said: "This study demonstrates through significant patient results that the "" listed in last year's UK NHS Improvement Document are correct. This is a really important finding for the hundreds of thousands of in the UK who suffer from AF and for the medical staff who treat them."

The results of the study are being made available to all NHS hospitals and practices and have been published in the current issue of the Journal of Clinical Pathology.

Explore further: Clot-busting medicine safe for use in warfarin-treated patients following stroke

Related Stories

Clot-busting medicine safe for use in warfarin-treated patients following stroke

June 26, 2012
The clot-busting medicine, tPA (tissue plasminogen activator), is safe to use in acute stroke patients already on the home blood thinner warfarin, according to researchers from Duke Clinical Research Institute (DCRI). This ...

Repeat CT scan urged for head trauma patients on warfarin

May 31, 2012
(HealthDay) -- Minor head trauma patients taking warfarin should have a repeat computed tomography (CT) scan prior to discharge to detect delayed hemorrhage, particularly in those with an initial international normalized ...

ARISTOTLE trial finds new drug may revolutionize the treatment of atrial fibrillation

October 26, 2011
New research has the potential to revolutionize the treatment of atrial fibrillation (AF), a condition affecting a quarter of a million Canadians which is expected to strike even more in the coming years, as the Canadian ...

Recommended for you

How genes and environment interact to raise risk of congenital heart defects

October 19, 2017
Infants of mothers with diabetes have a three- to five-fold increased risk of congenital heart defects. Such developmental defects are likely caused by a combination of genetic and environmental factors. However, the molecular ...

Mouse studies shed light on how protein controls heart failure

October 18, 2017
A new study on two specially bred strains of mice has illuminated how abnormal addition of the chemical phosphate to a specific heart muscle protein may sabotage the way the protein behaves in a cell, and may damage the way ...

Newborns with trisomy 13 or 18 benefit from heart surgery, study finds

October 18, 2017
Heart surgery significantly decreases in-hospital mortality among infants with either of two genetic disorders that cause severe physical and intellectual disabilities, according to a new study by a researcher at the Stanford ...

Saving hearts after heart attacks: Overexpression of a gene enhances repair of dead muscle

October 17, 2017
University of Alabama at Birmingham biomedical engineers report a significant advance in efforts to repair a damaged heart after a heart attack, using grafted heart-muscle cells to create a repair patch. The key was overexpressing ...

Physically active white men at high risk for plaque buildup in arteries

October 17, 2017
White men who exercise at high levels are 86 percent more likely than people who exercise at low levels to experience a buildup of plaque in the heart arteries by middle age, a new study suggests.

High blood pressure linked to common heart valve disorder

October 17, 2017
For the first time, a strong link has been established between high blood pressure and the most common heart valve disorder in high-income countries, by new research from The George Institute for Global Health at the University ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.