DEFINITION of 'Attribution Rules'. A set of rules created by Canada Revenue Agency (CRA) that prevents investors from transferring assets between family members with the intention of avoiding taxes. Next Up.
Causes of atrial fibrillation. The exact cause of atrial fibrillation is unknown, but it's more common with age and affects certain groups of people more than others. Atrial fibrillation is common in people with other heart conditions, such as: 1  high blood pressure (hypertension). 2  atherosclerosis.3  heart valve disease.4  congenital heart disease.auses of atrial fibrillation. The exact cause of atrial fibrillation is unknown, but it's more common with age and affects certain groups of people more than others. Atrial fibrillation is common in people with other heart conditions, such as: 1  high blood pressure (hypertension). 2  atherosclerosis.
The most common cause of stroke from an arrhythmia is atrial fibrillation. Atrial fibrillation can cause blood clots to form in the atria (top chamber of the heart) where they can be pumped out of the heart, to the brain, blocking a blood vessel and causing a stroke.Treatment for atrial fibrillation focuses in part on reducing the risk of stroke.lood clots can form in the heart's upper chambers because of atrial fibrillation, a disorder in which the atria quiver instead of beating effectively. Blood that isn't pumped completely out of the atria when the heart beats may pool and clot.