Second-Degree Atrioventricular Block Clinical Presentation

Updated: Jun 28, 2022
  • Author: Ali A Sovari, MD, FACP, FACC; Chief Editor: Jeffrey N Rottman, MD  more...
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Presentation

History and Physical Examination

In patients with Mobitz I second-degree atrioventricular (AV) block, symptoms may vary substantially, ranging from an absence of symptoms in well-trained athletes and persons without structural heart disease to recurrent syncope, presyncope, and bradycardia in patients with heart disease.

Most patients are asymptomatic. Patients may experience light-headedness, dizziness, or syncope, but these symptoms are uncommon. Patients may have chest pain if the heart block is related to myocarditis or ischemia. Patients may have a history of structural heart disease. The presence of absence of symptoms has important therapeutic implications.

In contrast to patients with Mobitz I AV block, those with Mobitz II AV block are more likely to experience light-headedness, dizziness, or syncope, though they may be asymptomatic as well. Patients may have chest pain if the heart block is related to myocarditis or ischemia.

Patients often have a regularly irregular heartbeat. Bradycardia may be present. Symptomatic patients may have signs of hypoperfusion, including hypotension.

Careful auscultation might show variations in the intensity of the first heart sound with variable AV conduction.