News & Events

Added to My Toolbox
Removed from My Toolbox
Added to My Toolbox
Removed from My Toolbox
Aug 12, 2015

Enlarged Heart Linked to Atrial Fibrillation

The largest study of its kind confirms that an enlarged heart increases risk for a common condition involving an irregular heartbeat.

Published in Heart, a journal of the British Cardiovascular Society, this study analyzed data from the Tromso Study—a large Norwegian research study started in 1974 to investigate risk factors for heart disease. Using surveys and health exams, the Tromso Study has collected information from thousands of Norwegian adults about various heart conditions, including atrial fibrillation (AFib).

AFib is a common type of irregular heartbeat that causes reduced blood flow to the body. While there are a number of well established risk factors for AFib, such as high blood pressure and diabetes, recent studies have found an association between an enlarged heart and increased risk for AFib. However, most of these studies were small and only followed patients for a short period of time.

To learn more, researchers analyzed data from more than 2,400 participants in the Tromso Study. On average, participants were 62 years old at the start of the study and were followed for 16 years, providing health information through periodic surveys. Participants also underwent echocardiograms, which use moving pictures to assess the size, shape and function of the heart. For the purposes of this study, researchers looked at the size of participants’ left atrium, which is one of the four chambers of the heart. An enlarged left atrium has been linked to AFib, as it can prevent the heart from pumping blood properly and may increase risk for an irregular heartbeat.

Based on tests results, researchers found that 19% of study participants had AFib; most were men. Individuals with a moderately enlarged left heart chamber were 60% more likely to have AFib than those with a normal heart size. Those with a severely enlarged left atrium were more than four times more likely to have AFib than those with normal heart chambers.

Findings confirm that an enlarged left atrium is an independent risk factor for AFib, similar to risk factors like obesity and diabetes. Although further research is needed to better understand the association between heart size and AFib, authors hope findings can help identify patients at risk for AFib or those at risk for complications from AFib, such as stroke and heart failure.

Afib is a common condition affecting roughly 2.7 million Americans. Although AFib significantly increases risk for stroke, healthy lifestyle choices, medication and other treatments can help reduce risk for complications. Addressing risk factors for AFib like high blood pressure can also go a long way in reducing risk for developing this condition. The more we know about risk factors that put us at increased risk for AFib, the more we can do to reduce risk for complications.

Questions for You to Consider

  • What is atrial fibrillation?

  • Atrial fibrillation is an irregular heart rhythm caused by abnormal, chaotic electrical impulses in the heart’s upper chambers, the atria. These electrical impulses, which interfere with the heart’s natural pacemaker, fire so rapidly the atria cannot beat with a regular rhythm or squeeze out blood effectively. Instead, they merely quiver while the ventricles, the heart’s lower chambers, beat rapidly.
  • How is atrial fibrillation treated?
  • In general, the goals of atrial fibrillation treatment are to promote a regular heart rhythm or rate and prevent blood clots, which can cause stroke. However, treatment strategies depend on the unique needs of each patient. Treatment options may include antiarrhythmic medication, blood thinners, and a variety of procedures that can help control atrial fibrillation.

Featured Video

Dr. Kanny S. Grewal, FACC, presents at a Living with Atrial Fibrillation event in Columbus, Ohio in Oct. 2014.


Bob's Story: Atrial Fibrillation

Learn how Bob Ek and his cardiologist, Scott J. Pollak, MD, FACC, work as a team to manage Bob’s atrial fibrillation.

Kathy Webster is CardioSmart

Kathy Webster was born with a heart defect that contributed to her developing atrial fibrillation. After two open heart surgeries, Kathy is dedicated to living an active and healthy lifestyle.

Marcus McCleery is CardioSmart

An AFib patient, Marcus lost a considerable amount of weight through diet and exercise. He maintains his heart-healthy ways and passes them on to fellow heart patients through volunteer work.

Fatty Acids May Help Prevent Recurrence of Atrial Fibrillation

N-3 polyunsaturated fatty acids found in fish and fish oils help control AFib.