Second degree atrioventricular block: Mobitz type II
- William H Sauer, MD
William H Sauer, MD
- Associate Professor of Medicine
- University of Colorado School of Medicine
Atrioventricular (AV) block is defined as a delay or interruption in the transmission of an impulse from the atria to the ventricles due to an anatomic or functional impairment in the conduction system. The conduction can be transient or permanent, with conduction that is delayed, intermittent, or absent. Commonly used terminology includes:
●First degree AV block – Delayed conduction from the atrium to the ventricle (defined as a prolonged PR interval of >200 milliseconds) without interruption in atrial to ventricular conduction.
●Second degree AV block – Intermittent atrial conduction to the ventricle, often in a regular pattern (eg, 2:1, 3:2), or higher degrees of block, which are further classified into Mobitz type I (Wenckebach) and Mobitz type II second degree AV block.
●Third degree (complete) AV block – No atrial impulses conduct to the ventricle.
●High-grade AV block – Two or more consecutive blocked P waves.
- Wenckebach KF. Zur Analyse der unregelmässigen Pulses. Ztschr klin Med 1899; 36:181.
- Mobitz W. Über die unvollständige Störung der Erregungsüberleitung zwischen Vorhof und Kammer des menschlichen Herzens. Z Gesamte Exp Med 1924; 41:180.
- Narula OS. Conduction disorders in the AV transmission system. In: Cardiac Arrhythmias, Dreifus L, Likoff W (Eds), Grune and Stratton, New York 1973. p.259.
- Peuch P. The value in intracardiac recordings. In: Cardiac Arrhythmias, Krikler D, Gododwin JF (Eds), Saunders, Philadelphia 1975. p.81.
- Puech P, Wainwright RJ. Clinical electrophysiology of atrioventricular block. Cardiol Clin 1983; 1:209.
- Takaya Y, Kusano KF, Nakamura K, Ito H. Outcomes in patients with high-degree atrioventricular block as the initial manifestation of cardiac sarcoidosis. Am J Cardiol 2015; 115:505.
- Nery PB, Beanlands RS, Nair GM, et al. Atrioventricular block as the initial manifestation of cardiac sarcoidosis in middle-aged adults. J Cardiovasc Electrophysiol 2014; 25:875.
- Birnie DH, Sauer WH, Bogun F, et al. HRS expert consensus statement on the diagnosis and management of arrhythmias associated with cardiac sarcoidosis. Heart Rhythm 2014; 11:1305.
- Rosen KM, Dhingra RC, Loeb HS, Rahimtoola SH. Chronic heart block in adults. Clinical and electrophysiological observations. Arch Intern Med 1973; 131:663.
- Gupta PK, Lichstein E, Chadda KD. Chronic His bundle block. Clinical, electrocardiographic, electrophysiological, and follow-up studies on 16 patients. Br Heart J 1976; 38:1343.
- Narula OS, Narula JT. Junctional pacemakers in man. Response to overdrive suppression with and without parasympathetic blockade. Circulation 1978; 57:880.
- Amat-y-Leon F, Dhingra R, Denes P, et al. The clinical spectrum of chronic His bundle block. Chest 1976; 70:747.
- Langendorf R, Cohen H, Gozo EG Jr. Observations on second degree atrioventricular block, including new criteria for the differential diagnosis between type I and type II block. Am J Cardiol 1972; 29:111.
- Goodfriend MA, Barold SS. Tachycardia-dependent and bradycardia-dependent Mobitz type II atrioventricular block within the bundle of His. Am J Cardiol 1974; 33:908.
- Epstein AE, DiMarco JP, Ellenbogen KA, et al. ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices): developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. Circulation 2008; 117:e350.
- Dhingra RC, Palileo E, Strasberg B, et al. Significance of the HV interval in 517 patients with chronic bifascicular block. Circulation 1981; 64:1265.
- Strasberg B, Amat-Y-Leon F, Dhingra RC, et al. Natural history of chronic second-degree atrioventricular nodal block. Circulation 1981; 63:1043.