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Life on Warfarin - Greater Freedom with Coaguchek

By Jonathan Upton

In October 1998 I underwent an aortic valve + root replacement with a CarboMedics 27mm 'CarboSeal' prosthesis for a leaky bi-cuspid aortic valve and aortic root aneurysm, previous Coarctation of Aorta.

The day after my surgery I was started on Warfarin to thin my blood and prevent blood clots from forming. At the time I was a little apprehensive how this might affect my life as I enjoy mountain-biking and climbing.

Unfortunately, my INR (International Normalised Ratio) the international standard for measuring the blood viscosity, rarely remains within the therapeutic range. The recommended INR range for my particular valve is 3.0 - 4.0. Despite following the advice on alcohol consumption and dietary guidelines, my INR would typically be too high or too low. This meant that I had to attend the anti-coagulation clinic at my local hospital on a weekly basis. Having to leave the office, find a parking space at the hospital and then wait to have blood taken would take a long time.

I did some research and learnt of a medical device called a 'Coaguchek Self-Tester' manufactured by Roche Diagnostics. I was so excited at what I read about it. In 2001 I became the proud owner of one. Since owning one, I have met other patients who use the device and it has been great sharing experiences. My GUCH Cardiologist and GP are very supportive of me self-testing.

Having a Coaguchek machine has completely changed my life for the better. I no longer have to attend the hospital for weekly blood-tests. However I do have periodic venous blood-tests as advised by the hospital (once every 2 or 3 months). Self-testing allows me to check my INR at home or away from home at any time I wish and get an accurate result within 3 minutes! This wonderful device has given me greater independence and the freedom to travel (something I really enjoy), without the worry of making arrangements to have my blood tested overseas at a hospital. Last year I took my Coaguchek machine to Australia and was able to monitor my INR. The hospital back in the UK was able to advise me over the phone about any alterations to my dose. My Coaguchek machine has also accompanied me to Turkey, Spain, Greece, Singapore and the USA.

Some may worry about how easy/difficult it is to use. I can assure you that it's a very easy piece of equipment to use. My Coaguchek machine came with a comprehensive 'step-by-step' user guide and an excellent video/DVD with demos on how to use the equipment. The test strips are even available on NHS prescription!

I have now been using my Coaguchek machine for 6 years and haven't looked back. It has improved my quality of life immensely and given me greater control over my life.

It is important to note that you must have the full backing of your GUCH cardiologist and GP before embarking on self-testing of your INR. Self-testing means working with your doctors, not independently of them and is not suitable for everyone.

If anyone would like to know more about the Coaguchek and 'self-testing' I am happy to share my experiences. You can also visit the website of ACE (Anti-Coagulation Europe) at:, which has lots of useful information, patient experiences and a message-board.

Roche Diagnostics have recently launched a new, smaller, lighter model Coaguchek called the 'XS' model. This model does not require test strips to be refrigerated and the new strips are also available on NHS prescription.

By Jonathan Upton, June 2007

Dr Kate English of Leeds General Infirmary has made the following comments.

Using home testing INR machines has been really valuable for some people who have to take warfarin, saving them time and lots of trouble attending the hospital for INR checks. It stops people missing lots of time off work, and can be really useful when you are on holiday. It is important to know that for some patients (particularly those with cyanosis) there are concerns about reliability of the INR measurements. Most GUCH cardiologists back the use of these machines, but you need to make sure their use is backed by whichever doctor runs your anti-coagulation service - this will usually be a local haematologist (blood doctor) or your GP. Some services are adamant they will not let you use them because they are not sure of the accuracy of the measurements.

Funding from The Somerville Foundation

If you and your GUCH Cardiologist think you would benefit from having a Coagucheck self-testing machine, you may be able to get funding from The Somerville Foundation to purchase one. Funding is only available on application from your GUCH Cardiologist or GUCH Nurse Specialist. All applications are dealt with individually and in the strictest confidence.

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