Heart arrhythmia

Heart arrhythmia

People can have a fast heartbeat during exercise or a slow heartbeat while sleeping. When your heart beats irregularly due to faulty electrical signals, it may be due to a heart arrhythmia. You may experience a heart that is racing or fluttering. Some heart arrhythmias can be harmless, while others can be life-threatening.  

To treat heart arrhythmia, your doctor may prescribe medications, perform catheter procedures, or device implantation. However, maintaining a healthy lifestyle can lower the risk of developing heart arrhythmias.

Type of heart arrhythmias

• Tachycardia (fast heartbeat) is when the resting heartbeat is over 100 beats per minute.
• Bradycardia (slow heartbeat) is when the resting heartbeat is less than 60 beats per minute.

Tachycardia

can be classified as follows:

• Atrial fibrillation (A-fib) results from chaotic cardiac signals, leading to temporary uncoordinated racing heart rhythm. However, left untreated, some people may have a continuous A-fib rhythm. A-fib is associated with other severe complications such as stroke.
• Atrial flutter occurs when the atria (upper heart’s chambers) beat too rapidly but more rhythmically than A-fib. It is also associated with
• Supraventricular tachycardia develops due to erratic heartbeat in the heart’s upper chambers. It can lead to heart palpitation.
• Ventricular tachycardia is the abnormal heart rhythm due to erratic electrical signals in the ventricles (the heart’s lower chambers). The heart beats so fast that there is inadequate blood to fill the ventricles to pump to the body. Ventricular tachycardia may not pose any symptoms in some people with a healthy heart. However, in those with heart disease, it can lead to a medical emergency.
• Ventricular fibrillation (V-fib) is the most life-threatening arrhythmic condition because the heart muscles quiver but do not contract or pump blood; there is no blood circulation or pulse. Patients will have cardiac arrest if they do not receive CPR or defibrillation. They will die within a few minutes.

Bradycardia

• Sick sinus syndrome is a heartbeat disorder frequent among the elderly. The scarring near the sinus node can interfere with the flow of electrical current, causing the heart to beat too slowly or stop beating for several seconds, leading to fatigue and syncope. Some may have a tachy-brady syndrome.
• Conduction block happens when the heart’s electrical pathway is blocked. The electric current from the upper chamber cannot travel to the lower heart chambers slowing down or stopping the heartbeat.

Premature heartbeats

Premature heartbeats are extra heartbeats that may come from the upper or lower heart chamber. You will feel like your heart is skipping a beat. Usually, they are not alarming but can trigger long-term arrhythmia, particularly in people with heart disease. It can lead to a weak heart in people with frequent and long-standing premature beats. Premature heartbeats can occur when you rest, exercise strenuously or consume stimulants like nicotine or caffeine.

Symptoms

The irregular heartbeat may be asymptomatic and could only be detectable during an exam for other medical conditions. However, some signs and symptoms may include:

• Chest pain
• Shortness of breath
• Tachycardia
• Bradycardia
• Fluttering heart
• Dizziness
• Sweating
• Syncope
• Fatigue
• Anxiety

When to see a doctor

Seek medical attention if you experience shortness of breath, dizziness, fainting, chest pain, and your heartbeat is too fast, too slow, or skipping. Ventricular fibrillation can cause your blood pressure to drop dramatically, leading to sudden collapse and eventual absence of pulse and breathing. If this happens, call for an ambulance immediately. If a CPR (cardiopulmonary resuscitation) - capable person is around, quickly start chest-compression-only CPR. Otherwise, try pressing the chest hard and fast at 100-120 compressions per minute. If an automated external defibrillator (AED) and a trained person are nearby, quickly follow the instruction to give an electric shock to restart the heartbeats.

How our heart works

Our heart consists of 4 chambers – 2 upper chambers or atria and 2 lower chambers or ventricles.

The sinus node in the right upper chamber is a natural pacemaker controlling the heart rhythm. It generates cardiac electric signals propagating to both upper heart chambers and through the AV node to the lower heart chambers. The AV node slows down the electric pulse wave slightly, allowing blood to flow from the upper to fill the lower heart chambers before triggering their contractions. An appropriate contraction sequence of the atriums and ventricles results in an effective cardiac cycle. A healthy heart has a resting heart rate of 50-90 beats per minute.

Causes

The irregular heart rhythm may be caused by

• Heredity
• Stress
• Smoking, drug use, excessive consumption of alcohol or caffeine
• Diabetes
• High blood pressure
• Hyperthyroidism
• Hypothyroidism
• Sleep apnea
• COVID-19
• Heart attack or coronary artery disease, cardiomyopathy

Risk factors

• High blood pressure
• Congenital heart disease
• Thyroid disease
• Obstructive sleep apnea
• Heart disease
• Electrolyte imbalances
• Certain medications and supplements
• Excessive consumption of alcohol
• Caffeine, nicotine, or illegal drug use

Complications from heart arrhythmia

• Shortness of breath
• Heart failure
• Syncope
• Heart failure
• Blood clots in the heart may travel through arteries to cause blockage in other organs, such as cerebral arteries, which can cause a cerebrovascular accident, and leg arteries, which can cause a lack of blood flow to the feet and legs, leading to gangrene.

Prevention

• Eat healthy foods which are beneficial for your heart.
• Exercise regularly.
• Keep a healthy weight.
• Quit smoking.
• Avoid alcohol.
• Have regular follow-ups or treatment if you have heart disease.
• Avoid stress or anger, which can lead to a racing heartbeat.

Diagnosis

Your doctor performs a physical exam and reviews your medical history and conditions. You may undergo some tests to diagnose if you have a heart arrhythmia, which types and how severe they are, and to help pinpoint the cause of arrhythmias such as thyroid disease or heart disease.

Typical tests for heart arrhythmias are:

• Electrocardiogram (ECG or EKG)
• Holter monitor
• Event recorder
• Echocardiogram (ECHO)
• Implantable loop recorder
• Exercise stress test to diagnose a stroke or heart arrhythmia, which may be associated with exercise.
• Tilt table test
  You will lie supine on a table with monitoring of your blood pressure, heart rate, and EKG. The table is tilted until it looks like you are standing up. This test can check your response to the more upright position. A positive test indicates the cause of syncope due to abnormal neurocardiac reflex.
• Cardiac Electrophysiological Testing
  Catheters tipped with electrodes are threaded through blood vessels to areas within the heart. The electrodes map out the electrical impulses throughout the heart. A cardiologist will measure cardiac electric current and perform cardiac stimulation according to a standard protocol to diagnose a heart arrhythmia and pinpoint the site of the cardiac abnormality. In most cases, cardiac ablation at the location that causes the condition will solve the problem.

Treatment

Regular follow-ups may be adequate in some people with heart arrhythmias. However, if the condition aggravates the risk of more severe heart conditions or interferes with your daily life, your doctor may suggest medications, therapies, cardioversion, catheter procedures, or heart surgery.

Medications

Most people with tachycardia need medications to control the heart rhythm. Some people with atrial fibrillation also take blood thinners to prevent the formation of blood clots. Taking the prescribed medications as directed is crucial to lowering the risk of complications.

Therapies

• Vagal maneuvers
  This method can help slow down your heartbeat by stimulating vagus nerves which control your heart rate. An arrhythmia may stop by coughing, putting your face in cold water, holding your breath, and straining. People with supraventricular tachycardia may try out this approach.
• Cardioversion
  It is to quickly bring the heart rhythm back to normal by sending an electrical current to the heart through chest electrodes. It is suitable for refractory arrhythmia, not responding to medications, particularly those with no severe underlying conditions such as hypotension, chest congestion, shortness of breath, and heart failure. This method restores normal heartbeat through medications or cardioversion.

Surgery or other procedures

• Catheter ablation.
  Threading one or more catheters tipped with electrodes through your blood vessels to the heart for radiofrequency ablation of abnormal heart tissue creating tiny scars that block faulty electrical signals and reset your heart rhythm.
• Pacemaker
  A pacemaker, implanted on the chest wall near the collarbone, connects with an electrode-tipped wire running through a blood vessel to a position at the apex of the heart and will discharge electrical impulses to stabilize the heart rate if slow heartbeats are detected. A pacemaker is usually for people with bradycardias that are not correctable by other means.
• Implantable cardioverter-defibrillator (ICD)
  An ICD implanted under the skin near the collarbone delivers either a high- or low-energy shock to restore normal heartbeats if it detects abnormal heart rhythms. This method is for people with ventricular tachycardia, ventricular fibrillation, cardiac arrest, or higher risks of sudden cardiac arrest.
• Coronary bypass surgery
  It is for people with heart arrhythmia accompanied by severe coronary artery disease. Coronary bypass surgery improves the blood flow to the heart.
• Maze procedure
  In patients with atrial fibrillation undergoing open heart surgery for other indications, the doctor may consider adding a concurrent maze procedure to cure the atrial fibrillation.

Lifestyle modification

• Stop smoking
• Exercise regularly: Try to exercise for 150-300 minutes per week at moderate to high intensity.
• Eat healthily: Cut salt and trans fats. Eat more fresh fruits, vegetables, and whole grains.
• Maintain a healthy weight
• Manage blood pressure and cholesterol levels
• Stop drinking alcohol.
• Attend every follow-up appointment.

Preparation

Consult a cardiologist if you think you have a heart arrhythmia; the earlier the detection, the more successful the treatment is.

If you experience a heart arrhythmia longer than 2-3 minutes, chest pain, shortness of breath, or fainting, call for an ambulance or have someone drive you to the nearest hospital.

What you can do

• When making a doctor appointment, ask if you need to do anything in advance, such as food restriction.
• Take note of the symptoms you are experiencing – related or unrelated to heart arrhythmia.
• List your medical conditions, medications, recent notable life changes, and a family history of stroke, heart disease, hypertension, and diabetes.
• Bring someone along to help you remember all the information.
• If you have symptoms and have a medical device, check and record your blood pressure, oxygen level, and EKG. There are now wearable gadgets that can record EKG, such as a smart watch.