Summary about Disease
Atrioventricular (AV) block is a type of heart block in which the electrical signal from the atria (upper chambers of the heart) to the ventricles (lower chambers of the heart) is either delayed or completely blocked. This disruption can cause the heart to beat too slowly, leading to various symptoms and potential complications. AV block is classified into three degrees of severity: first-degree (mildest), second-degree (partial block, Mobitz type I and Mobitz type II), and third-degree (complete block).
Symptoms
Symptoms of AV block can vary depending on the severity of the block. Some people, especially with first-degree AV block, may have no symptoms. Others may experience:
Lightheadedness or dizziness
Fainting (syncope)
Fatigue
Shortness of breath
Chest pain
Skipped heartbeats or palpitations
Slow pulse rate (bradycardia)
Causes
AV block can be caused by a variety of factors, including:
Heart disease: Coronary artery disease, heart attack, cardiomyopathy, congenital heart defects
Medications: Beta-blockers, calcium channel blockers, digoxin, antiarrhythmics
Aging: Degeneration of the heart's electrical conduction system
Electrolyte imbalances: High potassium levels (hyperkalemia)
Infections: Lyme disease, rheumatic fever, endocarditis
Inflammatory conditions: Lupus, rheumatoid arthritis
Surgery: Heart valve surgery
Medicine Used
The treatment for AV block depends on the severity of the block and the presence of symptoms.
Asymptomatic First-Degree AV Block: Usually requires no treatment.
Symptomatic AV Block:
Medications: If caused by reversible causes such as medications, dose adjustment or cessation of the offending medication.
Pacemaker: A permanent pacemaker is often required for symptomatic second-degree (especially Mobitz type II) and third-degree AV block. A pacemaker is a small device implanted under the skin that sends electrical signals to the heart to regulate the heart rate.
Is Communicable
Atrioventricular block is not a communicable disease. It is not caused by an infectious agent and cannot be transmitted from person to person.
Precautions
Precautions depend on the underlying cause and the presence of symptoms.
Medication Review: Review all medications with your doctor to identify potential causes or contributors to AV block.
Medical Alert: If you have a pacemaker, wear a medical alert bracelet or necklace.
Regular Check-ups: Regular follow-up appointments with your cardiologist are essential to monitor your heart condition and pacemaker function (if applicable).
Lifestyle Modifications: Follow your doctor's recommendations regarding diet, exercise, and other lifestyle factors to maintain overall heart health.
How long does an outbreak last?
AV block is not an infectious disease and does not involve "outbreaks." It is a chronic condition that may require ongoing management. The duration of symptoms depends on the severity of the block, the underlying cause, and the effectiveness of treatment.
How is it diagnosed?
AV block is diagnosed through a combination of:
Electrocardiogram (ECG or EKG): This test records the electrical activity of the heart and can identify characteristic patterns of AV block.
Holter monitor: A portable ECG that records heart activity over 24-48 hours or longer to detect intermittent AV block.
Event monitor: A device worn for several weeks to record heart activity when symptoms occur.
Electrophysiology study (EPS): An invasive procedure to assess the heart's electrical conduction system.
Timeline of Symptoms
The timeline of symptoms varies greatly depending on the type and severity of AV block:
First-degree AV block: Often asymptomatic and may be discovered incidentally during a routine ECG.
Second-degree AV block (Mobitz type I): May cause occasional skipped heartbeats or lightheadedness.
Second-degree AV block (Mobitz type II): More likely to cause dizziness, fainting, or fatigue.
Third-degree AV block: Can lead to severe symptoms, including frequent fainting, heart failure, and sudden cardiac arrest. Symptoms are persistent unless treated.
Important Considerations
Underlying cause: Identifying and treating the underlying cause of AV block is crucial.
Pacemaker safety: If you have a pacemaker, be aware of potential electromagnetic interference from certain devices.
Emergency preparedness: Know the signs and symptoms of worsening AV block and seek immediate medical attention if they occur.
Medication adherence: Take all medications as prescribed by your doctor.
Communication with your healthcare team: Maintain open communication with your cardiologist and other healthcare providers about any changes in your symptoms or concerns.