Bradycardia: Causes, Symptoms, Treatment & Prevention

What Is Bradycardia?

Bradycardia is a heart rhythm disorder (arrhythmia) that occurs when the heart's beating rate falls below 60 beats per minute (BPM) while at rest. For most adults and adolescents, the normal heart rate ranges from 60 to 100 beats per minute. For infants this starts from 80 BPM.

The heart's rhythm is controlled by electrical signals that originate in the sinoatrial (SA) node, often referred to as the heart's natural pacemaker. When these signals are delayed, blocked, or disrupted, the heart may beat more slowly than normal. As a result, the heart may not circulate blood as efficiently, which can affect the body's supply of oxygen and nutrients.

What Are the Types of Bradycardia?

Depending on the location of the cause of bradycardia, it is categorised as:

How Common Is Bradycardia in India?

In India, cardiovascular disease is very common, with clinical studies estimating a pooled prevalence rate of 11%. Heart diseases constitute roughly 31% of all deaths in the country, making it a serious health concern.

Bradycardia arrhythmias are a major part of the disease burden, especially among older people in the country aged over 65 years.

What Are the Symptoms of Bradycardia?

Symptoms of bradycardia can differ according to how slowed the heartbeat is and if it affects the perfusion (continuous supply of blood and oxygen) of organs. Typical symptoms of bradycardia include:

• Tiredness and weakness

• Dizziness and light-headedness

• Fainting and loss of consciousness

• Shortness of breath

• Pain and pressure in the chest

• Difficulty concentrating or memory problems

• Feeling ill during physical activity

What Causes Bradycardia?

Factors that can cause bradycardia include:

• Ageing-Associated Degeneration: The heart's conduction system deteriorates due to age, leading to bradycardia becoming increasingly prevalent in adults aged above 65 years.

• Heart Disorders: Coronary heart diseases, heart failure, and prior heart attacks may damage the SA node or the conduction pathway, resulting in impaired signalling within the heart.

• Drug Use: Drugs such as beta-blockers, calcium channel blockers, digoxin, and antiarrhythmics lower the rate of contraction of the heart as a side effect.

• Electrolyte Imbalance: Imbalances in electrolytes, such as potassium, calcium, or sodium, due to dehydration, renal failure, or dietary deficiencies, interfere with heart rate signalling.

• Infection: Lyme disease (tick-borne) or myocarditis (inflammation of the heart muscles) can impair the conduction of electrical signals within the heart.

• Sleep Apnea: Sleep apnea results in frequent interruptions in breathing, leading to the vagus nerve slowing the heart rate.

• Vasovagal Responses: Stressful or painful situations and prolonged periods of standing lead to activation of the vagus nerve, which slows the heart rate.

• Conditions at Birth: Some individuals are born with structural heart defects that affect the conduction system, causing bradycardia during infancy or childhood.

Complications Associated With Bradycardia

If bradycardia is left untreated or is improperly managed, the following complications can arise:

• Fainting and Falls: The more frequent the fainting spells, the higher the risk of sustaining serious injuries from falls, particularly for the elderly.

• Heart Failure: The continuous inadequacy of cardiac output eventually causes an overload of the heart muscle, leading to heart failure.

• Cardiac Arrest: Bradycardia and, in particular, heart block may cause death through fatal ventricular rhythm disorders or low heartbeats.

• Exercise Intolerance: The chronic problem of chronotropic incompetence (inability of the heart to increase its rate in response to physical activity) causes exercise intolerance. This condition lowers the quality of life and negatively impacts the heart.

• Memory Issues: Persistent symptomatic bradycardia can reduce blood flow to the brain and contribute to concentration difficulties or cognitive impairment in some individuals.

• Stroke: Patients with any underlying heart rhythm disorders that coexist with bradycardia are at risk of developing complications like a stroke.

When Should I See My Healthcare Provider?

Contact your physician without delay if either you or your family members experience the following:

• Unexpected fainting or near-fainting spells for no known reason

• Dizziness or lightheadedness while walking or moving around

• Feeling chest pains and experiencing difficulty breathing

• Extreme fatigue that does not improve after getting proper sleep

• Irregular heart rate that may be too slow or too fast after a self-checkup

• Experiencing breathlessness while performing exercises that you usually do effortlessly

• Concurrent use of heart medication (such as beta-blockers and digoxin) and the development of dizziness and exhaustion

How Is Bradycardia Diagnosed?

The following diagnostic methods can be used to detect irregular heart rhythm:

Note: A slow heart rate that is <60 BPM is normal for certain people, especially athletes who normally have a resting heart rate in the range of 40-50 BPM.

How Is Bradycardia Treated?

Bradycardia treatment depends on its causation, severity, and presence of accompanying symptoms. Treatment strategies usually include:

What is the Prognosis of Bradycardia

The prognosis of bradycardia is generally good and depends on its cause, severity, and whether symptoms are present.

Many people, especially athletes and healthy individuals, may have a naturally slow heart rate without any health problems. When bradycardia is caused by reversible factors like medications, electrolyte imbalances, or hypothyroidism, treatment of the underlying cause often leads to a favourable outcome.

However, untreated symptomatic bradycardia can increase the risk of dizziness, fainting, falls, heart failure, and, in rare cases, cardiac arrest. For patients with significant conduction disorders, such as sick sinus syndrome or heart block, pacemaker implantation can effectively manage symptoms and improve quality of life.

With timely diagnosis, appropriate treatment, and regular follow-up, most individuals with bradycardia can lead normal, active lives.

How to Prevent Bradycardia?

A reduction of cardiovascular risks can often significantly lower the chances of bradycardia development. Important tips include:

• Continuous monitoring of blood pressure and taking medication when needed.

• Managing diabetes effectively can help reduce the risk of cardiovascular complications that can affect heart rhythm.

• Proper consumption of medications prescribed by the cardiologists without altering the dosage.

• Treating thyroid disorders in time, because hypothyroidism is one of the most prevalent causes of bradycardia.

• Have regular checkups in case you have previously had some problems with your heart, like having a heart attack or arrhythmias.

• Taking care of sleep apnea because it causes bradycardia while sleeping.

• Avoiding drinking alcohol excessively, as it affects the work of the SA node, resulting in bradycardia.

Does Health Insurance Cover Bradycardia in India?

Yes. Many comprehensive health insurance policies in India cover the medically required treatment for bradycardia, such as pacemaker surgery. Coverage for the procedure normally includes:

• Pre- and post-hospitalisation expenses

• Cardiology consultations

• Diagnostic processes such as ECG, echocardiogram, and Holter monitor test

• Laboratory procedures

• Pacemaker device and surgery

However, if bradycardia is due to a pre-existing condition such as coronary heart disease, heart failure, or hypothyroidism, among others, the policy may come with a waiting period of up to 36 months, according to the terms and conditions of the policy document.

These conditions can vary based on plan and insurer.

How Much Health Insurance Coverage Is Needed for Bradycardia Treatment?

The health insurance coverage depends on the seriousness of the disease, the kind of treatment, the hospital, and the location of the patient.

For medication-induced or reversible bradycardia, there would only be outpatient consultation and diagnosis costs. In such situations, ₹5-10 lakh coverage is advisable to cater to your healthcare needs in the event of admission into the hospital.

Pacemaker implantation surgery can cost ₹2.4–₹4.5 lakh, depending on the treatment hospital in India, the cost of the equipment, the procedure itself, and the stay in the hospital. These costs can be higher in a private tertiary hospital in metropolitan cities, and thus, will require a higher coverage amount.

Older patients or those with other comorbidities like hypertension, diabetes, coronary artery disease, or a future need to replace the pacemaker's battery will need insurance coverage of ₹15–20 lakh.

To get the best health insurance coverage as per your needs, always review policy documents carefully.