Chronic Bradycardia: Understanding Symptoms and Impacts

Chronic bradycardia, also known as slow heart rhythm disorder, primarily includes sinus node dysfunction and atrioventricular (AV) block. Sinus node dysfunction, commonly referred to as sick sinus syndrome, occurs when the heart's natural pacemaker fails to function properly. This can lead to inadequate blood supply to vital organs such as the brain and kidneys, resulting in a range of symptoms.

Common Symptoms of Sinus Node Dysfunction

Individuals suffering from this condition often experience dizziness, fatigue, insomnia, and reduced mental alertness. These symptoms occur due to decreased blood flow to the brain and other organs. In some cases, patients may also feel lightheaded or experience memory issues due to prolonged low heart rates.

Understanding Atrioventricular Block and Its Stages

AV block is categorized into three degrees, each with varying symptoms. First-degree AV block typically presents no noticeable symptoms and is often detected only during routine electrocardiogram (ECG) testing. Second-degree AV block, however, may cause palpitations, chest discomfort, and general fatigue. These symptoms can interfere with daily activities and reduce overall quality of life.

Severe Symptoms in Third-Degree AV Block

Third-degree AV block, also known as complete heart block, has symptoms that largely depend on the ventricular heart rate and whether other heart conditions are present. Patients may experience extreme tiredness, dizziness, shortness of breath during physical activity, and in severe cases, episodes of syncope (fainting). This advanced stage can lead to Adams-Stokes syndrome, which involves loss of consciousness, seizures, and potentially life-threatening complications.

Comparing Congenital and Acquired AV Block

Those born with AV block often experience milder symptoms and may lead relatively normal lives with proper medical supervision. In contrast, individuals who develop AV block later in life tend to face more severe symptoms. These can include chronic fatigue, impaired physical performance, and sudden episodes of fainting. Without timely medical intervention, these symptoms can escalate into critical health events, including cardiac arrest.