Atrial fibrillation (AF or A-Fib) affects millions of people around the world and the incidence continues to rise. Men are more likely to have this condition than women. The risk of AF increases with age; however, half of those with AF are younger than 75. In the United States, AF is more prevalent among Caucasians than African-Americans or Hispanics.

What is atrial fibrillation? 

AF is caused by an electrical disturbance within the upper chambers of the heart, the atria. With this condition, the heart's electrical signals originate in a disorganized and rapid pattern, which causes the pulse to be fast and irregular. The atria no longer contract normally and this can lead to the formation of small blood clots within the left atrium. AF increases your risk of stroke and heart failure. 

What are the symptoms?

AF is often diagnosed during routine medical checkups because many people do not have symptoms. Others may experience heart palpitations, shortness of breath, dizziness, fatigue, and/or chest pain.

What increases your risk for AF?

Age older than 65 years and high blood pressure put you at risk for atrial fibrillation. 

Other risk factors to consider include: 

• Obstructive sleep apnea and obesity 
• Coronary artery disease and heart attack 
• Hyperthyroidism 
• Chronic use of alcohol 
• Heart failure and cardiomyopathy 
• Heart valve disease and rheumatic fever 
• Heart surgery (coronary artery bypass or valve surgery) 
• Infections like pneumonia 
• Congenital heart disease 
• Lung diseases including COPD, asthma, pulmonary emboli 
• Use of stimulants: decongestants, amphetamines, illicit drugs and even excessive caffeine or nicotine.
  

How is AF diagnosed?

An irregular pulse on physical exam suggests AF, but AF is confirmed by an electrocardiogram (EKG). AF is recurrent and may not be present at the time of the EKG. Longer monitoring of the heart rhythm may be required. Event monitors, which can be worn by the patient during their normal daily activities, may help detect AF. Simple lab tests and an echocardiogram may be required to exclude other contributing conditions (such as those listed above as risk factors). 

AF recurs 90% of the time and 90% of these recurrences are without symptoms. Therefore, people with confirmed AF have more AF than they realize, which can lead to strokes.

How is the risk of stroke related to AF? 

Age, hypertension, congestive heart failure, prior stroke or Transient Ischemic Attack (TIA - temporary loss or reduction of blood flow to parts of the brain), and diabetes —  each increases the risk of stroke in patients with AF. Anticoagulation with blood thinners like warfarin (Coumadin) or newer agents like dabigatran (Pradaxa) or rivaroxaban (Xarelto) or apixaban (Eliquis) reduces the risk of stroke in AF patients with a small increase in serious bleeding. 

How to treat and prevent? 

Treating AF reduces the risk of stroke and controls the rapid irregular heart rates that can lead to heart failure. Controlling precipitating conditions such as those listed above is important. Common medicines to control and decrease heart rate, including beta blockers (atenolol, metoprolol, carvedilol, or bisoprolol) and calcium channel blockers (diltiazem or verapamil) are often used first. Other agents may be added if AF recurs or if the rhythm remains irregular or too rapid. If the heart rate is much too fast or if the heart function is abnormal then a simple medical procedure to immediately replace AF with normal sinus rhythm may be required (electrical cardioversion). 

Healthy lifestyle choices will help protect you from heart disease and subsequently AF. These include daily exercise, a healthy/clean diet, weight control, avoiding caffeine, alcohol or other stimulants, managing high blood pressure and cholesterol. People with AF can live normal, active lives. Treatment can restore normal heart rhythms in some people. In others it can help control symptoms and prevent complications. Please follow your doctor's recommendations and be patient as treatment needs to be individualized to each patient. 

Until next time!

Stephanie Coulter, MD 

P.S. Read the Heart Information Center article: Atrial Fibrillation.

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