Stroke is the greatest threat to the life and health of people with atrial fibrillation (AF). In this group of patients, it occurs five times more often and usually has a more severe course than usual, doctors said on Wednesday at a press conference in Warsaw.
They announced a new era in the prevention of strokes in patients with AF, which is related to the emergence of drugs at least as effective as warfarin, known for half a century, but much more convenient and safer to use.
The first is dabigatran, which in October 2010 was registered in the USA and Canada for the prevention of strokes in patients with AF. In Europe, also in Poland, the registration of the drug in this indication is expected in the first quarter of 2011. Soon, the results of research on another drug – rivaroxaban, are also to be presented.
According to the hypertensiologist prof. Zbigniew Gaciong from the Medical University of Warsaw, it is estimated that 60-90 thousand people suffer from a stroke every year. Poles. About 30 percent. of them die in the first month after the onset of a stroke, and at least half of them do not recover and require care.
One in six cases of stroke affects a patient with atrial fibrillation, which is one of the most common arrhythmias. In patients with AF, the atria do not contract synchronously in accordance with the work of the ventricles, but fall into a chaotic, uncoordinated dance. In these patients, stroke is often more severe than usual and is associated with twice the risk of death.
It is estimated that about 0,5 million people in Poland suffer from flicker, which corresponds in number to the population of Poznań. The risk of the disorder increases with age and concerns as much as 10%. people over 80 years of age. Nevertheless, atrial fibrillation does not appear in the catalog of services provided by the National Health Fund – emphasized prof. Gaciong.
Among the risk factors for MP, the specialist mentioned primarily arterial hypertension and coronary heart disease. In a certain percentage of patients, the causes of this disorder cannot be identified. AF can be seen as palpitations, anxiety, weakness, fatigue, chest pain and even loss of consciousness. Sometimes it doesn’t cause any symptoms.
Stroke is the most dangerous complication of AF, reminded prof. Gaciong. Therefore, according to the latest European guidelines, stroke prevention has been recognized as the basic element of therapy for patients with AF.
Oral anticoagulants – warfarin and other coumarin derivatives – that reduce blood clotting, blocking the renewal of vitamin K in the body, are used as standard.
Unfortunately, warfarin therapy has numerous limitations that hinder its use in everyday practice, emphasized Dr. Rafał Dąbrowski from the Institute of Cardiology in Warsaw. Its effectiveness is reduced, for example, by foods rich in vitamin K, such as fresh vegetables (cabbage, lettuce, cauliflower, spinach), soy and liver. Warfarin also interacts with a variety of medications, including drugs that are frequently used such as ibuprofen and aspirin, certain antibiotics, medications for depression, antifungal medications, and alcohol and grapefruit juice.
The problem is that warfarin works in a very narrow range – when it thins the blood too little, the risk of an ischemic stroke increases significantly. When he does it too hard – the patient is at risk of a hemorrhagic stroke. This means that people taking the drug must regularly (sometimes even once a week) check blood clotting parameters and contact a doctor so that he can choose the dose appropriately.
These and other difficulties mean that the therapy is used by only half of the patients, although one fifth has contraindications, emphasized Dr. Dąbrowski. Therefore, patients and doctors are hopefully waiting for new drugs like dabigatran, which is at least as effective as warfarin, but has a better safety profile and does not require constant monitoring of clotting parameters, he added.
Joanna Morga (PAP)