(Enviado por Marcelo Gustavo Colominas [mgcolominas@gigared.com]. A disposição arquivo em *.pdf a quem solicitar)
The association of an irregular pulse with morbidity has been recognised since antiquity, and as long ago as 1628 William Harvey observed cardiac irregularity directly in animals. The modern emphasis on electrical demonstration of atrial fibrillation (AF) dates back a mere 100 years to the first publication by William Einthoven of an electrocardiogram showing the abnormality. Even the treatment of this disorder has a long and venerable history: William Withering published An account of the foxglove and some of its medical uses in 1785, and digoxin, the active extract of his remedy, remains in use today.
A patient developing AF in 2006 is faced with a wide array of potential therapies. A number of drugs can be employed to control the rapid heart rate, which is often an intrinsic part of AF; attempts can be made to restore sinus rhythm using drugs or direct current electrical shock; and an increasing number of surgical procedures are described. Despite the wide number of options available, there is an acknowledgement that AF is too frequently treated with the almost
automatic prescription of monotherapy with digoxin: this is still a useful drug over 200 years on but the best option for only a minority of patients. This failure to appreciate or implement proper treatment options in such a common condition makes AF an excellent topic for a national clinical guideline.
The guideline covers aspects of diagnosis and the management of AF in a number of different circumstances. It covers paroxysmal, persistent and permanent AF, considers AF developing after surgical procedures, and offers advice on haemodynamically unstable AF. Many of the recommendations relate to control of AF and the important decision of whether to attempt to restore sinus rhythm or concentrate on control of the heart rate. In a linked set of recommendations, the importance of considering anticoagulation in all these patients is emphasised.
This is sometimes neglected in clinical practice, but anticoagulation is of enormous potential benefit because of its role in stroke prevention, and one of the key recommendations in the guideline is that the risk of thromboembolism should be formally assessed. A simple clinical model that includes advice on appropriate prophylaxis is suggested for this purpose. Other key
recommendations cover the use of the electrocardiogram in diagnosis, and the preference in most patients for beta-blockers or rate-limiting calcium antagonists over digoxin for rate control.
The work of producing the guideline has been in the hands of a Guideline Development Group (GDG) comprising a small team from the National Collaborating Centre for Chronic Conditions working together with patients and health professionals with particular interest and experience in the management of AF. They have used the available evidence and their own clinical and personal judgement to produce guidance that is both clinically relevant and methodologically sound.
The GDG has had to evaluate a large amount of evidence during this process, and debate on some of the recommendations has been lively. The members have been driven throughout by the desire to produce a guideline that will be of value throughout the NHS. I am grateful to them for their hard work and for their expertise, and I am confident that they have produced a guideline that deserves to meet that aim.
Dr Bernard Higgins MD FRCP
Director, National Collaborating Centre for Chronic Conditions
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