An FDA panel has unanimously approved a new type of blood-thinning medication, Pradaxa (dabigatran etexilate) to help prevent stroke in people with atrial fibrillation. Atrial fibrillation (AF) is an irregular heartbeat in which the heart’s two small upper chambers (the atria) quiver instead of beating strongly. As a result, blood isn’t pumped completely out of them, and the trapped blood may pool and clot.
Atrial fibrillation is dangerous because of the risk that a clot may leave the heart and travel to the brain, resulting in a stroke. About 15% of strokes are a result of atrial fibrillation. AF can also lead to heart failure. The American Heart Association recommends aggressive treatment of this abnormal heart rhythm disorder, which affects about 2.2 million Americans – 3 to 5 percent of people over 65.
AF symptoms include dizziness or light-headedness, shortness of breath, fatigue, weakness, heart palpitations, a racing heart and chest pains, although some people have no obvious symptoms. The best way to confirm if you have AF is to have an electrocardiogram to measure your heart’s electrical activity. Atrial fibrillation can be caused by a heart attack, coronary artery disease, heart valve disease, high blood pressure or other medical problems. Heavy alcohol use, smoking, high consumption of caffeine, and use of illegal stimulants like cocaine and some prescription drugs (including decongestants and asthma medications) can also lead to atrial fibrillation.
Antiarrhythmics – prescription drugs to restore the heart’s natural rhythm – are the first line of defense against AF, along with lifestyle changes like quitting smoking, exercising, avoiding caffeine and alcohol and adopting a heart-healthy diet. Anticoagulant drugs, also known as blood thinner medications, are frequently prescribed to thin the blood and avoid the formation of clots. If AF symptoms fail to improve with prescription medications, electric shock to restore the heart’s regular beating pattern, radiofrequency ablation (cauterization of the problem area), surgery or insertion of an atrial pacemaker may be the next approach.
The newly approved Pradaxa is the first of a novel class of anticoagulant medication which inhibits an enzyme involved in blood clotting. In clinical trials, people with atrial fibrillation taking Pradaxa had fewer strokes than those taking the commonly prescribed anticoagulant medication warfarin. Warfarin is difficult to use as patients must be monitored with periodic blood tests, and the blood thinning medication interacts negatively with many other drugs and some foods. Germany’s Boehringer Ingelheim Pharmaceuticals Pradaxa is marketed in 75 mg and 110 mg capsules. Several American pharmaceutical companies are rushing to develop or get FDA approval for similar medications.