Atrioventricular Block

AV block causes include: 

• Ageing: The majority of AV block cases are caused by ageing; as we grow, the
  heart's electrical conduction system may sink, leading to AV block.
• Heart disease: Diseases such as coronary artery disease, heart attack,
  myocarditis and cardiomyopathy can lead to damage to the heart muscles and
  disrupt the electrical impulses between the atria and ventricles
• Medications: Beta-blockers, calcium channel blockers, and digoxin can slow
  down the heart rate, which can cause AV block.
• Inherited conditions:  Some heart conditions are rare genetic disorders
  inherited from the family, such as Lenegre disease and Lev disease, which can
  cause AV block.
• Other factors: AV block condition can be caused by conditions that impact the
  autonomic nervous system, such as sleep apnoea, carotid sinus
  hypersensitivity or by electrolyte imbalances, such as low potassium and
  magnesium level.

Some factors that may increase the risk of AV block include certain medications, such as beta-blockers, calcium channel blockers, and digoxin, which can lead to this condition.  Some rare genetic disorders, such as Lenegre disease and Lev disease, can also increase the risk of developing AV block. An imbalance in Electrolytes, such as Low levels of potassium or magnesium in the blood, can be caused by AV block. Autonomic nervous system disorders, conditions that affect the autonomic nervous system, such as sleep apnoea or carotid sinus hypersensitivity, can increase the risk of developing AV block. 
Its important to note that having one or more risk factors for AV block does not necessarily mean that a person will develop the condition. However, suppose you have any risk factors for AV block. In that case, its important to discuss your concerns with a healthcare provider and take steps to manage your overall health and reduce your risk of developing the condition.

Atrioventricular block management is not always preventable, mainly if its caused by factors such as ageing or genetic conditions. However, some steps can reduce or control the risk of developing this condition. 

These are:

• Maintaining a healthy lifestyle, such as regular exercise, following a balanced
  diet, and avoiding alcohol and tobacco intake, can keep your heart healthy
  and reduce the risk of developing heart disease.
• If you have underlying conditions that can increase the risk of this condition,
  such as heart disease, high blood pressure, and diabetes. It would help if you
  worked with the Doctor that can help you with these conditions.
• If you are taking medications that can be the risk factor in developing AV
  block, such as beta-blockers, calcium channel blockers, or digoxin, its
  essential to take your Doctor's advice and monitor your heartbeat regularly.
• Being overweight can increase the risk of developing heart disease and other
  conditions leading to AV block.
• Regular check-ups by visiting your Doctor can help detect early symptoms of
  heart problems, including AV block, and it will enable immediate treatment
  for the condition.
  Preventing AV block conditions is not always possible, but you can maintain a healthy lifestyle to control the risk of developing this condition.

There are three stages of AV block which include: 

• First-degree AV block: in the first stage, the electrical signal which passes from the atria and ventricles delays the signal; however, all the signals are transmitted from the atria to the ventricles, due to which the heart functions normally.
• Second-degree AV block: In this stage, some electrical signals that run from the atria to the ventricles are blocked or delayed. Depending on the extent of the blockage, Second degree AV blocks have two subtypes:
  • Mobitz type I (Wenckebach): this type refers to an irregular heartbeat because of the progressive lengthening of the delay between the atria and ventricles until one beat is stopped.
  • Mobitz type II: this type is characterized by periodic blockage of electrical signals from the atria to the ventricles, which can be associated with severe symptoms.
• Third-degree AV block: in the third-degree stage, there is a complete blockage of electrical signals, resulting in independent beating of the atria and ventricle that can slow down the heartbeat. This Degree is a severe form of AV block.

The treatment and symptoms for the heart electrical system blockage vary depending on the stage and type.