Arrhythmia, a condition where the heart beats irregularly, ranges from mild cases requiring no treatment to life-threatening forms that can lead to stroke or sudden death. Particularly when arrhythmia appears at a young age, it may indicate higher risk and requires accurate evaluation. Even a single episode of arrhythmia can be a warning sign of sudden cardiac death.
Professor Choi Jong-il of the Cardiovascular Medicine Department at Korea University Anam Hospital, one of Korea's leading experts in arrhythmia, recognized these risks and established Korea's first Hereditary Heart Disease Clinic.
"Genetic testing, which was limited in the past, has developed explosively with the introduction of NGS (Next-Generation Sequencing), enabling accurate diagnosis of hereditary arrhythmia," Choi said. "Although not common, atrial fibrillation occurring before age 60 should definitely be checked for genetic causes."
Seoul Economic TV's "Now, the Best Doctors" program will air an interview with Professor Choi on Sunday at 9 p.m., covering dangerous arrhythmias and the latest treatment methods.
'Abnormal Pulse' Requires ECG Identification
Arrhythmia literally means an abnormal pulse. Normally, the heart maintains a regular rhythm of 60 to 100 beats per minute. When this rhythm becomes too fast (tachycardia), too slow (bradycardia), or irregular, it is called arrhythmia.
While many people worry about arrhythmia when they feel their heart racing, palpitations do not always indicate arrhythmia. Heart rate can increase due to other causes such as nervousness, exercise, anemia, or thyroid conditions. The key is to properly identify the condition through electrocardiogram (ECG) testing when symptoms occur.
Arrhythmia diagnosis is made through ECG testing. However, accurate diagnosis requires capturing the ECG at the exact moment symptoms occur, which is practically difficult. Recently, medical devices that can continuously monitor heart rhythm are being used for diagnosis. These include patch-type ECG monitors (attached to the chest for three days to two weeks to record heart rhythm), wearable watches, and implantable loop recorders (for long-term monitoring inside the body for two to three years).
Hypertension and Diabetes Increase Arrhythmia Risk
High-risk groups for arrhythmia fall into two main categories. The first is people who already have heart disease. Patients with a history of heart failure or myocardial infarction have a higher likelihood of developing arrhythmias such as ventricular tachycardia or atrial fibrillation, and their risk of cardiac arrest also increases. The second is people with chronic diseases even without heart disease. Those with metabolic conditions such as hypertension, diabetes, obesity, or hyperlipidemia, or those in pre-disease stages, also face increased arrhythmia risk.
Although uncommon, some arrhythmias have genetic predisposition. "If a family member experienced unexplained sudden death or cardiac arrest at a young age, hereditary arrhythmia must be considered," Choi said. "If there is a family history of sudden death, regardless of age, I recommend getting at least one ECG and echocardiogram."
Additionally, when specific patterns appear on ECG tests, or when echocardiography or MRI shows thickened heart muscle or abnormal findings indicating cardiomyopathy, detailed evaluation including genetic testing is necessary.
Arrhythmias Requiring Treatment vs. Those That Can Be Monitored
Not all arrhythmias require treatment. Cases that definitely need treatment include ventricular tachycardia, ventricular fibrillation, atrial fibrillation, severe bradycardia, and hereditary arrhythmias that can cause cardiac arrest. These cases require active treatment such as medication, procedures, artificial pacemakers, or implantable cardioverter-defibrillators (ICD). In contrast, low-risk arrhythmias with minimal symptoms, such as mild premature ventricular contractions or premature atrial beats on ECG, can be managed with lifestyle modifications and observation alone.
For atrial fibrillation and some ventricular tachycardias, medication is the first-line treatment. If symptoms are well controlled, medication alone may suffice, but if control is difficult or side effects occur, procedures are considered. For bradycardia patients, artificial pacemakers are the standard treatment, sending electrical stimulation to maintain normal heartbeat when the heart cannot beat regularly on its own.
Catheter Ablation for Tachyarrhythmias
Catheter ablation is the key treatment for tachyarrhythmias, where the heart beats too fast. The procedure involves inserting electrodes into the heart to find the circuit causing the arrhythmia and destroying that area using radiofrequency, cryotherapy, or pulsed field energy.
"Eighty to ninety percent of atrial fibrillation originates around the pulmonary veins," Choi explained. "We use radiofrequency energy to block abnormal electrical signals from the pulmonary veins from spreading throughout the atrium."
Pulsed field ablation, in particular, reduces damage to surrounding tissue while shortening procedure time, and Choi expects it to become an important pillar of atrial fibrillation treatment in the future.
Ventricular tachycardia originates in the ventricles, the lower chambers of the heart, making procedures much more difficult. "The heart muscle is thick and there are large blood vessels and valves nearby, so sometimes we need to access not just inside the heart but also the epicardium," Choi said. "For this reason, it is safer to have procedures performed at institutions with experienced medical staff and proper equipment."
For patients who have experienced cardiac arrest or have high risk of arrhythmia recurrence due to reduced heart function, implantable cardioverter-defibrillators are inserted to reduce risk. These devices automatically deliver strong electrical shocks to restore normal rhythm when life-threatening arrhythmias occur.
Choi emphasized that patients should not be afraid and should actively seek treatment, as there are various treatment options for arrhythmia. "I have a 104-year-old patient who has an artificial pacemaker and takes medication, but is healthy enough to take the subway to the hospital by himself," he said. "This is entirely possible when good lifestyle habits and appropriate medical treatment go together."
Korea University Anam: A 'Quaternary Hospital' for Arrhythmia
Professor Choi described Korea University Anam Hospital's Arrhythmia Center as a "quaternary hospital in the arrhythmia field." The hospital has pioneered many firsts in Korea, including the first atrial fibrillation procedure, introduction of ECG testing, and research on wearable patch and watch-based arrhythmia monitoring.
"Our center treats many difficult cases such as refractory and recurrent arrhythmia patients, while also focusing on education," Choi said. "About 30 medical professionals from university hospitals across Korea and more than 50 from the Asia-Pacific region have received training here and returned to their countries and hospitals to continue providing treatment."
