Thursday, July 27, 2017

How Is Atrial Fibrillation Linked To Cryptogenic Stroke?

Stroke or also known as brain attack, occurs when the supply of blood to the brain is interrupted or reduced because either the blood supply is blocked or blood vessel within the brain ruptures. When this happens, the brain does not get enough oxygen or nutrients causing brain cells to die.

There are 3 main kinds of stroke, namely ischemic strokes caused by blockages or narrowing of the arteries, hemorrhagic strokes caused by arteries in the brain either leaking blood or bursting open, and transient ischemic attacks (TIAs), also referred to as mini-strokes. TIAs produce short-lived stroke symptoms and usually do not bring permanent injury to the brain. They, however, do serve as warning signs for future strokes and indicate that there is a partially blocked artery or clot source in the heart. 

It is interesting to note that about 30 to 40 percent of ischemic strokes, and nearly half of all TIAs are cryptogenic. A cryptogenic stroke is one for which there is no apparent underlying cause. 

Being one of the potential causes of cryptogenic stroke, atrial fibrillation (AF) is hard to detect because of its symptomless. It may come and go at random, or they can be chronic and range from several days in length to being present all the time. It causes one of every 6 strokes usually major. As many as 8 of every 10 patients with a stroke brought on by AF die or are disabled. Other causes for cryptogenic stroke include Patent Foreman Ovale (PFO), inherited thrombophilias, aortic arch plaque, infectious, autoimmune and inflammatory states.

When AF occurs, blood flow from one chamber of the heart to the next and from the heart to the rest of the body becomes inconsistent. This may cause blood to pool in the upper chamber of the heart known as atria and starts to clot. Pieces that break off from a clot may travel through arteries and eventually arrive at the brain. If a clot becomes entrapped, it blocks the flow of blood to the part of the brain that vessel supplies. This causes a stroke.

Underlying heart disease and age are the 2 major risk factors, though AF can happen at any age without any apparent cause. AF can be sporadic and difficult to pinpoint. However, if one can watch out for symptoms like quivering or fluttering heartbeat, feeling like your heart is racing or beating irregularly, fluttering or thumping in the chest, dizziness, shortness of breath, anxiety, fainting (a result of less blood getting to the brain), and confusion (another result of less blood to the brain), and inform doctor accordingly may save his or her life. 

Doctors can use ECG to show AF even when there are no symptoms. But monitoring the heart for signs of AF may require more than the 24 hours, which was recommended by the previous guidelines. Some research suggested monitoring for a period of over 30 days may reveal 5 times more cases of AF in patients. Patients who are diagnosed with AF could take anticoagulation medicines to help keep that first stroke from happening, reducing the risk by at least 50 percent.

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