Second Degree Atrioventricular Block 2:1

With 2:1 atrioventricular block, it is impossible to know whether it is Mobitz I (nodal) or Mobitz II (infranodal) based on the surface ECG; therefore, 2:1 AV block is simply referred to as “2:1 AV block.” When the QRS is narrow, as in this case, Mobitz I is more likely; however, it is prudent to assume the worst scenario (i.e., Mobitz II).

Examples

References

  1. Costa D Da, Brady WJ, Edhouse J. Bradycardias and Atrioventricular conduction block. Br Med J. 2002;324(March):535-538.
  2. de Pádua F, Pereirinha A, Marques N, Lopes MG, Macfarlane PW. Conduction Defects. In: Macfarlane PW, van Oosterom A, Pahlm O, Kligfield P, Janse M, Camm J, eds. Comprehensive Electrocardiology. London: Springer London; 2010:547-604.
  3. Kusumoto FM, Schoenfeld MH, Barrett C, et al. 2018 ACC/AHA/HRS Guideline on the Evaluation and Management of Patients With Bradycardia and Cardiac Conduction Delay: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhyth. Circulation. 2019;140(8):e382-e482.