Atrial fibrillation can be caused by many different factors. A brief explanation; The heart has four chambers, the ventricles which are the main pumps and are more muscular and the atria which sort of top off the venrtricles before they pump (atrial kick). They contribute about 25% to the cardiac output. Afib is an irregular heart rhythm, the conduction pathway originates in the SA node and is conducted to the av node where there is a slight delay and then proceeds to the ventricles where they are stimulated to contract. In betwwen the atria and the ventricles is a nonconductive layer of tissue, which is very important to prevent runaway ventricular responses from afib. Every cell in the heart has the ability to generate a heart beat So afib is caused by rapid, firing of electrical signals in the atria. this prevents coordinated contractin of the atria- you lose 25% of your cardiac output as well as an increased ventricular response in some people. This condition is the most common cardiac arrythmia and is seen quite a bit. The problem is that clots can form in the atria due to stagant blood, so an aspirin should be taken everyday just incase he goes into w/o knowing it. What causes it? Things that irritate the heart like alcohol- which is quite common (holiday heart) and Ive seen ephedrine do it as well- caffeine should be eliminated. Another component that causes this is structural abnormalities such as a leaky valve. Mitral regurgitation of a moderate degree will stretch out the left atrium and once the atria is stretched out the electrical impulses wont conduct normally and will "chase their tails" and cause electrical loops where the signal just goes round and round causing fibrillation. The problem with afib is that it too stretches out the atria so if you have it once, you're much more likely for it too occur. Also high blood pressure causes this as well, so if a person has had uncontrolled bp they are much more likely to get this. High bp can also exacerbate any leaky valves and so on. Now the question is what kind of cycle should he take. Since there are no studies on this I think the safe route would be not to take any drugs that may cause water retention simply because of the blood pressure issue. If he decides to, a low dose is called for and blood pressure must be strictly controlled. I would suggest the EQ or the var and skip the test unless its low dose. Again all of this is in general, like I said alot of things cause atrial fibrillation.
