AFib in the Summer: Know the Triggers

People with atrial fibrillation should take extra precautions during hot weather, when dehydration and alcohol consumption can trigger symptoms and make the common heart rhythm disorder more difficult to manage, according to experts in the Smidt Heart Institute at Cedars-Sinai.

Atrial fibrillation, or AFib, is a condition in which the heart's upper chambers beat irregularly, often causing a rapid heartbeat. Some people with AFib also experience chest discomfort, shortness of breath or heart palpitations. Others may notice only mild fatigue during activity. And still others may feel no symptoms at all. AFib also increases the risk of stroke.

"That's why it's especially important to carefully manage AFib in the summer, when people may spend more time in the sun, lose fluids through sweating, and drink more alcohol on vacation, at barbecues and at other outdoor social gatherings," said Archana Ramireddy, MD, a clinical electrophysiologist in the Smidt Heart Institute. "Older adults are especially affected by the heat, even if it may not seem obvious at first."

In recognition of AFib Awareness Month in September-when Southern California often experiences some of its hottest weather-the Cedars-Sinai Newsroom spoke with Ramireddy about steps people with AFib can take to stay healthy.

What summer factors can trigger an AFib episode?

Hot weather can put added stress on the heart, but heat itself isn't necessarily the primary concern. Dehydration is of special concern because people lose fluids through sweating. Older adults may be particularly susceptible to heat-related dehydration because the body's ability to conserve fluids and regulate temperature can decline with age. Alcohol is another concern because it is a well-recognized trigger for AFib, and people tend to drink more during the summer while vacationing, spending time outdoors and attending social gatherings.

Should people with AFib drink plain water to stay hydrated, or do they need electrolytes?

Plain water is usually the best choice. Electrolyte drinks may be helpful in some circumstances, although individual needs vary based on heat exposure, activity level, how much a person has been sweating, and underlying health conditions.

What are the signs of dehydration?

Signs of dehydration can include dark urine, dizziness, dry mouth, fatigue, confusion and a rapid heartbeat. If symptoms are prolonged or severe, or if a person also is experiencing chest discomfort or shortness of breath, they should seek medical attention.

Is coffee off-limits for people with AFib?

One cup of coffee a day generally isn't a concern. Even two cups may be acceptable, although for some patients I recommend switching extra servings to decaf or half-caf. It's most important that people pay attention to their own bodies. If caffeine consistently triggers symptoms, cutting back is recommended. I'm far more concerned about the consumption of multiple energy drinks, because high doses of caffeine and other ingredients in these drinks can increase the risk of arrhythmias.

Is it safe for people with AFib to exercise in the summer?

I encourage regular exercise for my patients with AFib. If physical activity consistently triggers episodes, the underlying AFib should be evaluated and treated rather than simply avoiding exercise. That said, it's best to avoid strenuous exercise during the hottest part of the day and to stay well-hydrated if outside in the heat. To combat overheating, seek air conditioning, drink plenty of water, take a cool shower or use cool towels.

What if a person thinks they may have AFib?

If a person has heart palpitations and isn't sure what is causing them, capturing an episode can be key for diagnosis and treatment. This is where wearable devices, such as smartwatches, can play a role. If a device can record an ECG, or electrocardiogram, during an episode, a physician can review the tracing to determine whether it is consistent with AFib. Wearable devices have helped us identify more patients sooner, allowing us to begin treatment sooner. Preventing stroke is a major goal of AFib treatment. People who have been diagnosed with AFib should work with their healthcare team to determine whether further evaluation by a cardiac electrophysiologist is appropriate.

Read more from Cedars-Sinai Stories and Insights: Atrial Fibrillation-Know the Warning Signs