AFib is an electrical malfunction that affects the atria, the two upper chambers of the heart, causing them to beat “irregularly irregular.” This means there is no set pattern that affects the rhythm. The result may be insufficient blood supply throughout the body.
Complications can be severely debilitating, such as stroke or even death. Risk factors include age (the older we get, the higher the probability), obesity, high blood pressure, premature atrial contractions and diabetes.
When AFib is symptomatic, symptoms include shortness of breath, chest discomfort, light-headedness, fatigue and confusion. It can be diagnosed by electrocardiogram (ECG), but more likely with a 24-hour Holter monitor or a 14-day Zio Patch. The challenge in diagnosing AFib is that it can be intermittent.
There are two main types of AFib, paroxysmal and persistent. Paroxysmal is acute, or sudden, and lasts for less than seven days, usually less than 24 hours. It tends to occur with greater frequency over time, but comes and goes.
Persistent AFib continues past seven days. AFib is a progressive disease, meaning it gets worse, especially without treatment.
Medications are meant to treat either the heart rate or rhythm or prevent strokes from occurring. There is also ablation, an invasive procedure that requires threading a catheter through an artery, usually the femoral artery located in the groin, to reach the heart.
In one type of ablation, the inappropriate nodes firing in the walls of the atria are ablated, or destroyed, using radiofrequency. This procedure causes scarring of atrial tissue. When successful, patients may no longer need medication.
Role of obesity
There is good news and bad news with obesity in regard to AFib. Let’s first talk about the bad news. In studies, those who are obese are at significantly increased risk.
In the Framingham Heart Study, the risk of developing AFib was 52 percent greater in men who were obese and 46 percent greater in women who were obese when compared to those of normal weight. There were over 5,000 participants in this study with a follow-up of 13 years.
The Danish Diet, Cancer and Health Study reinforces these results by showing that obese men were at a greater than twofold increased risk of developing AFib, and obese women were at a twofold increased risk.
Now the good news: Weight loss may help reduce the frequency of AFib episodes. In a randomized controlled trial of 150 patients, those in the intervention group, which lost 32 pounds, saw a significant reduction in atrial fibrillation severity score (AFSS) compared to those in the control group.
AFSS includes duration, severity and frequency of atrial fibrillation. All three components in the AFSS were reduced in the intervention group compared to the control group.
There was a 692-minute decrease in the time spent in AFib over 12 months in the intervention arm, while there was a 419-minute increase in the time in AFib in the control group. This is the first study to demonstrate that managing risk factors may actually help manage the disease.
Anecdotally, in those who already have AFib, caffeine may increase the frequency of symptomatic occurrences. With my patients, when we reduce or discontinue caffeinated substances, such as coffee, tea and chocolate, the number of AFib episodes declines.
I have also heard similar results from colleagues and their patients. So, think twice before running out and getting a cup of coffee if you have AFib. What we really need are formal studies to confirm these findings.
The bottom line is this: AFib is dangerous and has severe potential complications, so if you have AFib, consider avoiding caffeine and, if you’re obese, there’s no better reason to lose weight.