A heart block, also known as an atrioventricular block (AV Block), is a disorder where the heart beats more slowly or with an irregular rhythm. It results from an issue with the electrical pulses that regulate your heartbeat. Three different forms of heart blocks exist.
The least serious type of heart block, a first-degree block, may not even show any symptoms. The impulses in this type are delayed.
Second-degree heart block: Can result in uncomfortable symptoms that require medical attention. The impulses are momentarily inhibited in this type.
The most severe heart block, a third-degree block is occasionally a medical emergency. This type fully blocks the electrical signal.
Heart block can be quite harmful. Severe heart block can cause sudden cardiac arrest (your heart stops beating quickly) if ignored, however it usually causes dizziness or fainting spells. The severity of your heart block will determine your symptoms.
A first-degree heart block may not present any troubling symptoms.
Symptoms of second-degree heart block include fainting, dizziness, and the sensation that your heart is skipping beats. Chest pain, nausea, fatigue, difficulty breathing, or shortness of breath.
The following symptoms of third-degree heart block, which can be fatal: extreme fatigue, irregular heartbeats, dizziness, fainting, and Heart arrest.
Book an appointment with your Cardiologist if you experience any of these symptoms or call the emergency number right away if you experience any chest pain or discomfort.
Congenital heart block, which affects some people, is a birth defect. However, heart block typically appears later in life. Acquired heart block is what this is, and it can be brought on by:
Other cardiac issues, like a heart attack
Prescription medications
Other health issues, like Lyme disease
Undergoing heart surgery
If a baby is born with a heart defect or if their mother has an autoimmune disease like lupus, they are more likely to suffer congenital heart block.
Laboratory studies
Troponin levels: if AV block is suspected as a result of ischemia/infarction.
Electrolyte levels (hyperkalemia) and drug levels (e.g., digitalis), if raised potassium level or drug toxicity is detected.
In cases of systemic illness, investigations of infection (Lyme titers), myxedema (TSH levels), or connective tissue disease (ANA).
Electrocardiography
24-hour and/or extended monitoring
12-lead ECG recordings; rhythm/monitor strips
Implantable loop recorder
Additional modalities
Electrophysiologic test: To pinpoint the block's position and associated tachyarrhythmias
Echocardiography can be used to evaluate ventricular function (especially if an implantable device is required)
Exercise test: To determine whether AV block gets better or worse with exercise.
You can be referred to an electrophysiologist by your Cardiologist. Doctors that specialise in the electrical activity of the heart are called electrophysiologists.
Typically, a heart block only needs to be treated if symptoms are present.
You might need to have a pacemaker, a small device that is implanted in your chest and provides frequent electrical pulses to maintain your heart beating normally, depending on the reason of your heart block and your symptoms.
Altering heart disease drugs or treatments relieves heart block.
If heart block isn't adequately treated, consequences including heart failure, arrhythmia, heart attack, or even sudden cardiac arrest can be fatal.
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