Arrhythmia (available in Chinese only)

– The information has been reviewed by Dr. Lo Ka Yip, David




It is estimated about 70 to 80 thousand people in Hong Kong are affected by arrhythmia (also known as cardiac or heart arrhythmia), with the risk of the disease increasing with age. Atrial fibrillation and ventricular fibrillation are the most common types of arrhythmia. Generally if a patient with arrhythmia is not properly treated, their mortality rate will triple, and the risk of stroke and heart failure will be about 5 and 3 times higher respectively than that of ordinary people.


What is Arrhythmia? 

Unusual heartbeats that are too fast (over 100 beats per minute), too slow (less than 50 beats per minute) or palpitations (intermittent fast or distrubed heartbeats) are collectively categorized as irregular heartbeats. The same is true for abnormal heartbeats, which contain “bradycardia” for less than 60 beats per minute, and “tachycardia” for over 100 beats per minute. The follow are the most common arrhythmia conditions:

  • Ventricular Fibrillation (VF): The most serious type of arrhythmia is also the “culprit” behind half of all sudden heart disease deaths. The rapid and chaotic heartbeat hinders the lower heart cavity from pumping blood and oxygen to the brain and may even stop the heart entirely, leading to death within a few minutes.

  • Atrial Fibrillation (AF): The upper heart chamber and atrium of the patient will vibrate rapidly and chaotically, causing the heartbeat to become irregular, sometimes as high as 200 beats per minute. Although not directly fatal, it may cause other heart problems and congestive heart failure. The risk of stroke also increases by 5 times compared to normal.

  • Ventricular Tachycardia (VT): Common symptom is an extremely fast heartbeat, which can turn into fatal ventricular fibrillation. Requires early monitoring and treatment.

  • Sick Sinus Syndrome (SSS): Also known as sinus node dysfunction, it refers to a series of malfunctions in the sinus node such as an abnormally slow heart rate during rest, failure to speed up during exercise, failure to respond to adrenaline regulation, and more.

  • Supraventricular Tachycardia (SVT): Risk is relatively low, and usually comes and goes suddenly ranging from a few minutes to a few hours. Can cause palpitations, dizziness, or shortness of breath





  • 心室纖維顫動(VF): 最嚴重的心律不正,也是半數心臟病猝死的「元兇」。急速而混亂的心跳妨礙下心腔將血液和氧份泵至腦部及身體,甚至令心臟完全停頓,數分鐘內便會死亡。
  • 心房纖維顫動(AF): 患者的上心腔、心房會急速及紊亂地顫動,令心跳變得不規則,有時每分鐘高達200次。雖然不會直接致命,卻會導致其他心臟問題及充血性心臟衰竭,患者的中風機會,比一般人高5倍。
  • 心室心搏過速(VT) : 症狀是心跳極快,可以轉化成致命性的心室顫動,須及早監察和治療。
  • 病竇症候群(SSS): 又稱竇房結功能異常,指一系列竇房結功能失調,如在休息時心跳率會不正常地緩慢、運動時不能加快、未能因應腎上腺素調節等等。
  • 心室心搏過速(SVT): 危險性相對較低,通常驟來驟去,由數分鐘以至數小時不等,可引起心悸、昏暈或氣促。

Some patients with arrhythmia may show no symptoms, or they may feel that their heart beat is fast, slow, or irregular. Normally when people are at rest, a normal heart range is between 60 to 100 beats per minute for adults. If the heart beats less than 60 beats per minute, they will experience fatigue, shortness of breath, dizziness, pannus, chest pain, weariness, or even dizziness and fainting.

Similarly, if the heart’s rhythm is abnormally fast or uneven, it can also affect oxygen flow to vital organs. In severe cases, it can cause dizziness, fainting, shock, or even sudden cardiac death.

Causes + Risk Factors
Causes + Risk Factors

Arrhythmia is mainly caused by problems with the atrial sinus node. Once the function of this area is impaired, or atrial and ventricular conduction is affected, the electrical impulse responsible for coordinating heart contractions will be affected, which may cause arrhythmia.


Risk Factors

  • Genetic disease (genetic disorder), family history
  • Cardiovascular disease
  • Hypertension
  • Thyroid disorders
  • Diabetes
  • Imbalanced electrolytes
  • Pressure and mental stress from urban life
How is Arrhythmia diagnosed? + Treatment
How is Arrhythmia diagnosed? + Treatment
  • 24 Hour ECG Examination: Patients must carry a small “Holter” device with them to monitor and record their heartbeat, allowing cardiologists to assess the degree of palpitations or arrhythmia

  • Echocardiogram: Ultrasounds are used to obtain a clear image of the heart to detect irregular contractions. Depending on the patient’s condition, cardiologists may recommend that the patient undergo both exercise electrocardiography and coronary angiography

  • Electrophysiological Examination: Thin catheters are introduced into the heart through blood vessels to measure the heart current signal and conduction path. This allows for the patient’s heartbeat pattern to be uncovered, resulting in a detailed heartbeat frequency record



There are many treatments for arrhythmia. A cardiologist will determine which is most appropriate according to the type of arrhythmia and the patient’s condition.

  • Catheter Ablation: The most common and standard treatment method today, this minimally invasive surgery is usually performed under local anesthesia. The cardiologist guides the catheter towards the ventricle and uses electrodes at its end to find and correct parts causing the abnormal heartbeat. It can deal with a variety of arrhythmia problems with a high success rate, and is expected to replace medication in the future.

  • Instrument Implants: Artificial cardiac defibrillators, pacemakers, or cardiac resynchronization therapy devices are implants in the chest of arrhythmia patients. The heart is stimulated through preadjusted electrical pulses to correct the heartbeat’s rhythm, thus improving cardiac function and reducing the risk of sudden death.

  • Medication: The new generation of anticoagulant drugs proved to be effective against strokes. In addition to reducing its incidence rate, the risk of intracranial hemorrhages is lower than that of traditional anticoagulant drug warfarin. The new drug uses fixed doses, allowing patients to no longer have to undergo regular blood tests or restricted diets.