“A Pulse of 50—Still Okay to Exercise?” ... Myths and Facts About Arrhythmia [Health Talk]

[Financial News] It may seem natural to think that people with arrhythmia should avoid exercise, but regular exercise can actually protect the heart. However, with large temperature swings these days, it is important to adjust the time you exercise.
It is best to avoid outdoor exercise at dawn when temperatures are low, as well as early-morning hikes. After getting up, stretch thoroughly indoors and drink warm tea or water. When going out, dress in layers to maintain your body temperature.
Kwon Chang-hee, a professor in the Division of Cardiology at Konkuk University Medical Center, said, “There is no need to hold back just because you have arrhythmia. Doing aerobic and strength-training exercises vigorously enough to make you sweat at least three times a week strengthens the heart muscle and blood vessels.”

On days with large temperature swings, the time to be most careful is in the morning, when you step outside from a warm indoor space into the cold. A sudden drop in temperature stimulates the sympathetic nervous system, which tenses the body, and the heart beats faster than usual to maintain body temperature. If this stimulation is repeated, the heart muscle becomes more sensitive, making arrhythmia more likely.
Professor Kwon explained, “Autumn is a time when the number of patients with acute heart conditions such as heart attacks increases. Sharp temperature changes during seasonal transitions affect the autonomic nervous system, causing blood vessels to constrict and blood pressure to rise, which puts strain on the heart.”
On days with large temperature swings, your heart may race or feel as if it has dropped with a thud. It is easy to dismiss this as the weather or fatigue, but if these symptoms recur or are accompanied by dizziness or a feeling that you might faint, you should consider the possibility of arrhythmia.
The heart can be compared to a house with an upper and a lower floor. The atria, on the upper floor, receive blood that has circulated throughout the body, while the ventricles, on the lower floor, act as pumps that send the blood back out to the body. Electrical signals keep this house moving in rhythm. The “sinoatrial node” in the upper part of the right atrium generates regular electrical signals, which spread through the atria and ventricles and cause the heart to contract.
A normal pulse is regular, at 60 to 100 beats per minute. Arrhythmia is the general term for a heartbeat that is excessively fast, slow, or irregular. Generally, a rate below 60 beats per minute is considered bradycardia, while 100 or more is considered tachycardia. Atrial fibrillation, in which the pulse beats irregularly, and premature beats, which occur earlier than expected, are also common types of arrhythmia.
Symptoms also vary by type. Bradycardia can cause dizziness or lightheadedness as if you are about to faint, and make it difficult to keep up with others during exercise. With tachycardia, your heart may pound and feel tight even when you are still, as if you had just run 100 meters. Atrial fibrillation can cause persistent fatigue and an irregular pulse. If your heart is pounding, checking your pulse for one minute to see whether it is regular can help when you seek medical care.
However, a slow pulse is not always a problem. Professor Kwon urged people not to worry excessively, saying, “Even if your pulse is around 50 beats per minute, treatment is often unnecessary if you have no symptoms. Arrhythmias come in many types, and not all of them need treatment, so I hope you will discuss your diagnosis and treatment plan thoroughly with your doctor.”

Treatment depends on the type of arrhythmia. For premature beats, lifestyle changes are usually the first step, and medication is used if symptoms are severe. If medication does not control them and premature beats account for 15% or more of all beats on a 24-hour electrocardiogram, radiofrequency ablation may be considered to eliminate the area causing the arrhythmia with heat.
Bradycardia caused by reduced function of the sinoatrial node is difficult to treat by raising the heart rate with medication. If there are symptoms, a pacemaker is implanted in the body to generate signals in its place. An implantable cardioverter-defibrillator may be considered for those who have experienced ventricular tachycardia or whose heart function has declined significantly. If a dangerous rhythm occurs, the device delivers an electric shock on its own to restore a normal heartbeat.
For atrial fibrillation, the most common type of arrhythmia, treatment combines anticoagulants to prevent stroke with measures to control the heart rate or restore a normal rhythm. Anticoagulants are especially important for older people and those with diabetes, high blood pressure, or a history of stroke.
If medication does not control the condition, a procedure to block the openings of the pulmonary veins may be considered. The pulmonary veins are the passageways through which blood flows from the lungs into the heart, and about 90% of the abnormal electrical signals that cause atrial fibrillation originate there. Depending on the method used to block them, the procedures are classified as radiofrequency ablation, cryoballoon ablation, or pulsed-field ablation.
Radiofrequency ablation, which uses radiofrequency heat to block the affected area, has been used for a long time. Cryoballoon ablation places a balloon at the tip of a catheter against the opening of a pulmonary vein and freezes it, blocking a wider area at once and potentially shortening the procedure. Pulsed-field ablation, which has recently drawn attention, uses a strong electric current for an extremely brief moment to block the area and may reduce the risk of damage to surrounding tissue, including the esophagus. The appropriate method is chosen based on the patient’s condition and the progression of the arrhythmia.
Professor Kwon explained, “Atrial fibrillation is a chronic, progressive disease that requires lifelong management, but a procedure can slow deterioration of the atria and, even if the condition recurs, reduce recurrence from 10 times to once and episodes from 10 minutes to one minute. It is important to reduce the amount of time the heart is exposed to atrial fibrillation and lower the risk of complications such as stroke or death.”
 

[email protected] Jung Myung-jin, Medical Correspondent Reporter