Afib & Stroke

Atrial fibrillation (Afib) is the most common of all cardiac arrhythmias. It currently affects over 2.7 million Americans1 and has an estimated 2050 prevalence of approximately 12 million. Chances of developing atrial fibrillation increase with age and those forty years of age or older have a 1 in 4 chance of developing it in their lifetime2.

Afib is a serious cardiac condition. It increases the risk of stroke by five times3, slows down the flow of blood throughout the body, and can lead to acute heart disease.

Atrial fibrillation is characterized by an irregular and fast heartbeat. As in all cardiac arrhythmias, Afib is induced by abnormal electrical impulses that occur within the heart. In the case of Afib, the electrical impulses affect the atria (upper chambers of the heart), causing accelerated, erratic contractions.

These erratic contractions prevent the atria from producing full beats. Instead, they quiver rapidly, giving the ventricles (lower chambers of the heart) less time to fill with blood. Because the ventricles do not have enough time to fill with a sufficient amount of blood, they are not able to pump enough blood to the body’s other organs.

The quivering atria also contribute to the high risk of stroke associated with atrial fibrillation. Since the atria cannot pump with sufficient pressure, small amounts of blood may pool in the left atrial appendage (a hollow sac attached to the heart’s left atrium). This can lead to a stationary blood clot which can eventually work its way into the bloodstream and the brain. Ninety-five percent of detected blood clots (thrombi) in patients with atrial fibrillation occur in the left atrial appendage5.

Anticoagulant medications can reduce the risk of stroke significantly in patients with atrial fibrillation although they carry a risk of severe bleeding. The Stroke Feasibility Study using the AtriClip LAA Exclusion System is enrolling Afib patients contraindicated to anticoagulation medication and as a result do not have a reasonable alternative available.

 


1,3 January, C., Wann S., Alpert J., Calkins H., Cleveland J., Cigarroa J., Conti J., Ellinor P., “2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society.” Circulation. 2014 March.Lloyd-Jones, D., Wang, T., Leip, E., Larson, M., Levy, D., “Lifetime Risk for Development of Atrial Fibrillation: The Framingham Heart Study,” Circulation. August 16, 2004.Jeff S. Healey, MD, Eugene Crystal, MD, Andrew Lamy, et al. “Left Atrial Appendage Occlusion Study (LAAOS): Results of a randomized controlled pilot study of left atrial appendage occlusion during coronary bypass surgery in patients at risk for stroke.” American Heart Journal. 2005 Aug; 150:288-93.