What is Cardiac Arrhythmia?
It is a condition where there is an abnormality in the heart’s electrical conduction, causing the heart to beat faster or slower than normal, and the rhythm may be regular or irregular. Some types of cardiac arrhythmia are medical emergencies that can be life-threatening, leading to cardiac arrest and death. Generally, arrhythmias can be divided into two main types: abnormal slow heartbeats (Bradyarrhythmia) and abnormal fast heartbeats (Tachyarrhythmia).
What symptoms indicate cardiac arrhythmia?
We can classify symptoms indicating cardiac arrhythmia into 3 types:
- In cases of excessively fast heartbeats, a pulse over 80 beats per minute in adults at rest is considered faster than normal. Some may experience palpitations, dizziness, lightheadedness, chest tightness, easy fatigue, fainting, paralysis, stroke, or cardiac arrest and death.
- In cases of excessively slow heartbeats, a pulse under 60 beats per minute in adults at rest (except in athletes who train regularly and are healthy, where a slow heartbeat such as 50 beats per minute is still considered normal). If the heart beats too slowly, the blood pumped from the heart to the brain is insufficient, causing dizziness, lightheadedness, or fainting.
- Besides beating too fast or too slow, the heart may beat irregularly, which further reduces the amount of blood pumped from the heart to supply various organs, especially the brain and the heart itself, leading to ischemia and subsequent symptoms.
Causes and risk factors for cardiac arrhythmia
Cardiac arrhythmia can arise from many causes and other risk factors, such as abnormalities in the heart’s electrical conduction system, which may result from ischemic heart disease, myocarditis caused by certain viruses, pre-existing heart diseases like congenital heart defects, valvular stenosis or regurgitation, stimulation by caffeine or stimulants such as amphetamines, alcohol, some weight loss drugs, and bronchodilators. Aging also causes degeneration of the heart’s electrical system, which is why this condition often occurs in the elderly. Certain diseases can trigger arrhythmias, such as hypertension, hyperlipidemia, diabetes, hyperthyroidism, and electrolyte imbalances like magnesium or potassium abnormalities.
Steps for cardiac disease diagnosis
- History taking and physical examination, checking pulse rate, rhythm regularity, pulse strength, and auscultation of heart sounds. Valvular stenosis or regurgitation often accompanies fast arrhythmias originating from the atria.
- Electrocardiogram (ECG) to detect abnormalities in the heart’s electrical waves and the type of arrhythmia at that time.
- Chest X-ray to assess heart size and chambers.
- 24-48 hour Holter monitoring, as some arrhythmias cannot be detected by a single ECG. The patient wears the monitor for 1-2 days, and the data is analyzed to classify the arrhythmia type.
- Echocardiogram (ultrasound of the heart).
- Cardiac electrophysiology study to assess the heart’s electrical conduction system.
- Coronary angiogram to image the coronary arteries.
- Additional blood tests to check blood concentration for anemia, kidney function, thyroid hormones, electrolytes, and markers of myocardial ischemia.
Heart disease and treatment methods
- Medication aimed at controlling the heart rate to prevent it from being too fast (Rate control), controlling the heart rhythm to be regular (Rhythm control), and anticoagulants to prevent blood clots in the atria and embolism in other vital organs.
- Carotid sinus massage in cases of fast arrhythmias originating from the atria. Doctors may massage the neck to stimulate the parasympathetic nervous system, which controls heart rate, to slow the heartbeat.
- Electrical cardioversion to restore normal heart rhythm. Ventricular arrhythmias reduce blood output from the heart and can cause rapid death. Effective resuscitation involves using a defibrillator. The sooner the treatment, the better the outcome.
- Radiofrequency ablation, where a catheter is inserted into the heart to destroy abnormal areas identified by electrophysiologic study (EP). This method eliminates the origin or shortcut pathways causing arrhythmia, resulting in a high cure rate.
