Chaos is defined as a state of disorder, disarray, a lack of organization. Atrial fibrillation (Afib) is a disorganized, chaotic heart rhythm. Chaos theory is a branch of science and mathematics that seeks to find connections and repetitive patterns in chaotic systems (for example weather patterns, stock market trends, or understanding complex medical systems). It seeks to bring order to the chaos. This review will try to bring some order to the chaotic world of Afib.
During normal heart rhythm, the atria (the upper chambers of the heart) beat smoothly and rhythmically. In Afib, the atria fibrillate and beat chaotically, like a bag of squirming worms. Afib is triggered by extra beats (premature atrial contractions) that arise in the pulmonary veins (there are 4 pulmonary veins bringing blood from the lungs into the left atrium). The extra beats start the rhythm, then multiple electrical wavelets travel in a random, chaotic way through the atria. The wavelets disrupt the normal, organized contraction of the atria, leading to disorganization and “squirmy atria”.
Afib is the most common arrhythmia encountered in cardiology. About 3 to 6 million people in the US currently have Afib and that number is expected to rise in the coming years (to about 12 million by 2030). The prevalence of Afib rises with age. About 1% to 3% of 60-year-olds have Afib while 10% to 11% of 80-year-olds have it. Afib causes serious medical problems, increasing the risk for stroke by 5 times, the risk for congestive heart failure by 3 times and the risk of death by 2 times.
Risk factors for developing Afib include: high blood pressure, valvular heart disease, congestive heart failure, heart attack, sedentary lifestyle, obesity, alcohol, smoking, sleep apnea, and thyroid disease. However, it is not just the old and the sick who have Afib. Famous people who have had Afib include: George HW Bush, Dick Cheney, Tony Blair, Barry Manilow, Elton John, Roger Moore (aka, James Bond), Kareem Abdul-Jabbar, Larry Bird, Jerry West, Billie Jean King, Mark Spitz, and Mario Lemieux. The athletes on this list might be surprising, but there are many Olympic athletes who have had Afib. In fact, studies have shown that high volume exercisers, professional and amateur, are prone to Afib. Elite, Olympic rowers are seven times more likely to develop Afib compared to the average person.
Afib is diagnosed on an electrocardiogram (EKG) or on a rhythm strip. Often, Afib is fleeting and short- and long-term monitors have been developed to try to catch Afib. An example of a short-term monitor is a Holter monitor, which assesses the heart’s rhythm for one to three days. An event monitor is a patch that provides more long-term evaluation and is worn for one to four weeks. Wearable devices (such as an Apple watch) can detect Afib and the detection algorithms are getting better and better. Still, wearable devices are only about 70% accurate in determining Afib. The diagnosis must be confirmed by a medical-grade device.
The treatment for Afib occurs on several levels. Almost everyone is put on a blood thinner to prevent blood clots and strokes. If the heart rate is fast, beta blockers (such as metoprolol) or calcium channel blockers (for example diltiazem) are used to slow the heart rate. If appropriate, cardioversion is recommended. Cardioversion is performed with the patient under light anesthesia. An electric shock is given via pads placed on the chest. This resets the heart rhythm and, in many cases, returns the patient to normal sinus rhythm. In addition, antiarrhythmic agents may be employed (for example, amiodarone, sotalol or flecainide). Antiarrhythmics are powerful medications with many side effects. In addition, they are only moderately effective. The best agent, amiodarone, can only keep a patient in normal rhythm 60% of the time. What else can be done to bring order to Afib?
Catheter ablation is an invasive procedure to try to cure Afib. Cardiologists who specialize in arrhythmias (electrophysiologists) place a catheter around each of the four pulmonary veins and create a scar (using radiofrequency or pulsed field energy). The scar acts as an electrical barrier, preventing the wavelets in the pulmonary veins from escaping and precipitating Afib in the atria. The ablationists can eliminate Afib about 80% of the time; so let’s call them the chaos crushers. What can the average person do to avoid Afib and an ablation? Several lifestyle modifications can be initiated to prevent Afib. Being sedentary is a huge risk factor for Afib. Moderate exercise will decrease the risk substantially. If obese (BMI > 27), losing 10% or more of body weight almost cures Afib. Treating sleep apnea decreases the risk of Afib by 40%. Lastly, stopping or cutting back on alcohol consumption lowers the risk of Afib.
Life can be chaotic. Your heart rhythm doesn’t have to be. Take care of the factors that you can control. See your doctor and treat any medical issues that might lead to Afib (bring blood pressure down or treat sleep apnea, for example). Initiate the lifestyle changes noted earlier to decrease the risk of Afib. This is the theory on how to control the chaos king of cardiology, Afib.
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