Heart block

Heart block is a condition where there is a delay or interruption in the electrical signals that regulate the heartbeat. It's categorized into first, second, and third degrees, based on the severity of the blockage. Symptoms can range from mild to severe, and treatment depends on the degree of block and associated symptoms. If you have concerns about heart block, it's crucial to consult with a healthcare professional for proper evaluation and guidance.

Heart block can have various causes, including:

1. **Age-related degeneration:** As people age, the electrical conduction system of the heart may degenerate, leading to heart block.

2. **Ischemic heart disease:** Lack of blood flow to the heart muscle due to coronary artery disease can damage the conduction system.

3. **Inflammatory conditions:** Conditions like myocarditis, which involve inflammation of the heart muscle, can disrupt the electrical pathways.

4. **Certain medications:** Some medications, especially those used for heart conditions, may interfere with the normal conduction of electrical signals.

5. **Infections:** Certain infections, like Lyme disease, can affect the heart and lead to heart block.

6. **Autoimmune diseases:** Conditions where the immune system attacks the body's own tissues can impact the heart's conduction system.

7. **Congenital factors:** Some individuals may have a congenital predisposition to heart block due to abnormalities in the heart's structure.

There are three main types of heart block:

1. **First-degree heart block:** This is the mildest form, characterized by a slowing of the electrical signals as they pass through the atrioventricular (AV) node. Although there is a delay, all signals eventually reach the ventricles.

2. **Second-degree heart block:** This type is divided into two subtypes: Mobitz Type I (Wenckebach) and Mobitz Type II. Mobitz I involves a progressive delay in the signals until one is blocked, while Mobitz II is characterized by occasional blocked signals without preceding warning.

3. **Third-degree heart block (complete heart block):** In this severe form, all electrical signals between the atria and ventricles are blocked. The atria and ventricles beat independently, leading to a slower and often irregular heartbeat.

Symptoms of heart block can include:

1. **Fatigue:** Due to the heart's inefficient pumping.

2. **Dizziness or lightheadedness:** Resulting from decreased blood flow to the brain.

3. **Fainting (syncope):** Especially in more severe cases or during physical exertion.

4. **Irregular heartbeat (arrhythmia):** As the heart's normal rhythm is disrupted.

5. **Shortness of breath:** When the heart is unable to pump blood effectively.

6. **Chest pain:** Occurs in some cases, particularly with underlying heart disease.

Diagnostic evaluation for heart block typically involves:

1. **Electrocardiogram (ECG or EKG):** This is a primary tool to identify heart block and determine its type by measuring the electrical activity of the heart.

2. **Holter monitor:** A portable ECG device worn for an extended period to record heart activity continuously. It helps capture intermittent heart block that may not be evident during a standard ECG.

3. **Event monitor:** Similar to a Holter monitor but used for shorter durations. It is activated by the patient when symptoms occur to capture specific episodes.

4. **Exercise stress test:** Measures heart activity during physical exertion, helping to identify exercise-induced heart block.

5. **Echocardiogram:** Uses sound waves to create images of the heart, assessing its structure and function, and identifying any underlying heart conditions.

6. **Blood tests:** These may be done to check for signs of heart muscle damage or assess electrolyte levels, which can impact heart function.

The management of heart block depends on its type and severity. Here are common approaches:

1. **Observation:** Asymptomatic first-degree heart block may not require specific treatment but should be monitored regularly.

2. **Medications:** Certain medications, such as atropine or isoproterenol, may be used to address symptoms or transient heart blocks. However, medication efficacy can vary.

3. **Temporary pacing:** In acute situations, temporary pacing via external devices can be used until a long-term solution is established.

4. **Permanent pacing:** For persistent or symptomatic heart block, especially third-degree heart block, a permanent pacemaker may be implanted. This device helps regulate the heart's rhythm by sending electrical signals when the heart's natural conduction system fails.

5. **Lifestyle modifications:** Adopting a heart-healthy lifestyle, including regular exercise, a balanced diet, and avoiding smoking, can support overall cardiovascular health.