Atrioventricular Block Clinical Presentation

Updated: Nov 14, 2017
  • Author: Chirag M Sandesara, MD, FACC, FHRS; Chief Editor: Jose M Dizon, MD  more...
  • Print
Presentation

History

The degree atrioventricular (AV) block is generally associated with the severity of symptoms and clinical history. Common presentations and symptoms are outlined below for the different types of AV block.

Any level of AV block leading to profound bradycardia may also lead to life-threatening torsade de pointes (TdP). This is due to the inverse relationship between bradycardia and repolarization time; it may prolong the QT interval and predispose a patient to TdP especially if there is a long short interval. 

First-degree AV block

History

  • High vagal tone
  • Acute inferior myocardial infarction (MI)
  • Use of antiarrhythmic medication(s)
  • Being a conditioned athlete
  • Hypokalemia, hypomagnesemia
  • Degeneration of the AV node

Symptoms

  • None
  • Shortness of breath
  • Exercise intolerance
  • Fatigue

Second-degree AV Block

History

  • Inflammatory disease
  • Infiltrative disease
  • Hyperkalemia
  • Catheter ablation of the slow pathway
  • Valve replacement surgery
  • Acute MI

Symptoms

  • Fatigue
  • Shortness of breath
  • Exercise intolerance
  • Dizziness
  • Syncope
  • Chest pain

Third-degree AV Block

History

  • Degenerative disease
  • Infiltrative disease
  • Myocarditis
  • Neuromuscular disease
  • Ischemia/infarction
  • Hypoxia
  • Hyperkalemia
  • Use of antiarrhythmic medication(s)

Symptoms

  • Fatigue
  • Shortness of breath
  • Exercise intolerance
  • Lightheadedness, dizziness
  • Syncope
  • Chest pain
  • Neck palpitations
Next:

Physical Examination

Routine physical examination does not lead to the diagnosis of first-degree atrioventricular (AV) block. Second-degree AV block may manifest as bradycardia (Mobitz II), irregularity of the heart rate (Mobitz I), or a variable pulse and variable neck vein distention.

Third-degree AV block may be associated with profound bradycardia. In cases of concomitant structural heart disease, pulmonary edema and jugular venous distention may be noted. Cannon A-waves may be observed intermittently due to right atrium contraction against a closed tricuspid valve. A variable S2 and variable strength of the pulse is noted. 

Previous