Elizabeth Blackwell (3 February 1821 â 31 May 1910) was the first female doctor in the United States and the first on the UK Medical Register. She was the first openly identified woman to graduate from medical school, a pioneer in educating women in medicine in the United States, and was prominent in the emerging women's rights movement.
According to Medilexicon's medical dictionary, atrial fibrillation is fibrillation in which the normal rhythmic contractions of the cardiac atria are replaced by rapid irregular twitchings of the muscular wall; the ventricles respond irregularly to the dysrhythmic bombardment from the atria..
The result is a fast and irregular heart rhythm. The heart rate in atrial fibrillation may range from 100 to 175 beats a minute. The normal range for a heart rate is 60 to 100 beats a minute. Abnormalities or damage to the heart's structure are the most common cause of atrial fibrillation.