Optimal practice review: recommendation reminders detail
|Date issued:||June 2006|
Atrial fibrillation (AF) is a condition that affects the heart. It occurs when the electrical impulses controlling the heartbeat become disorganised, so that the heart beats irregularly and too fast. As a result, the heart is not able to efficiently pump blood around the body and the pulse is irregular. This may cause symptoms such as palpitations, chest pain or discomfort, shortness of breath, dizziness and fainting. If severe, these can be life threatening and require immediate treatment. However, many people with AF have no or only mild symptoms.
AF may increase the risk of blood clots because when the heart beats irregularly, the blood does not flow properly through the heart and the rest of the body. People with AF may need medication to reduce or prevent this risk.
Most people with AF will be offered medication known as an anticoagulant to ‘thin’ their blood and reduce the risk of clotting. Depending on individual circumstances, this may be needed before or after cardioversion (the use of medicine or electric shock, or sometimes both, to help the heart return to its normal [sinus] rhythm).
Some of the anticoagulants used to prevent blood clots are aspirin, warfarin and heparin. The decision on which drug to use, and how long for, is based on the presence of certain risk factors (such as high blood pressure, diabetes or a heart condition), whether the person has had a stroke (which can happen if a clot blocks an artery to the brain) and the type of AF they have.
As well as benefits, there are common risks associated with anticoagulants, such as a risk of haemorrhage. Except in an emergency, doctors should discuss the benefits and risks with people before a decision is made whether to go ahead with anticoagulation treatment.
The onset of AF is associated with the formation of blood clots that can break away and lead to the blockage of blood vessels (known as thromboembolism). However, the evidence reviewed by the NICE Guideline Development Group indicated that the development of blood clots in the heart, and the immediate risk of thromboembolism, is thought to be minimal within the first 48 hours after AF. In addition, common clinical practice indicates that cardioversion may be safely performed without the need for oral anticoagulation if AF has been present for less than 48 hours.
This evidence supported the recommendation that, if sinus rhythm is successfully restored with cardioversion, anticoagulation is not required in people with AF that is confirmed to have lasted less than 48 hours.
This page was last updated: 09 September 2009