Wenckebach block

DiMarco JP, Sellers TD, Belardinelli L (1984) Paroxysmal supraventricular tachycardia with Wenckebach block evidence for re-entry within the upperportion of the atrioventricular node. J Am Coll Cardiol 3(6) 1551-1555... 

Lengthened Absent or depressed, elevated after 20 s Short, shifted toward T-wave Increased, decreased over time, T starts on top of R, diphasic, negative Tall T, surpassing R, sometimes inverted 0.4-0.8 mg/kg NaCN HRf, bradycardia, Wenckebach, heart block, V-flutter, VF 0.1 mg/kg NaCN, bradycardia, incomplete AV blockade, VF Leimdorfer (1950) (cats) Paulet (1955) (dog)... 

Paroxysmal atrial tachycardia with Wenckebach (Mobitz type I) atrioventricular block has been reported in a patient with a serum digoxin concentration of 3.2 ng/ml (39) and in a patient who in error took three times the recommended dose (40). 

Spodick DH. Well concealed atrial tachycardia with Wenckebach (Mobitz 1) atrioventricular block digitalis toxicity. Am J Geriatr Cardiol 2001 10(1) 59. 

Clonidine causes sinus bradycardia and atrioventricular block, as illustrated by two cases, one a 10-year-old boy (6) and the other a 71-year-old woman (7), who developed Wenckebach s phenomenon. Clonidine was also studied in seven patients subjected to electrophysiological studies after 5 weeks of therapy (8). It slowed the sinus rate and increased the atrial pacing rate, producing Wenckebach s phenomenon, indicating depressed function of the sinus and AV nodes. 

AV conduction - 2nd degree block, Mobitz I (Wenckebach) [10] AV conduction - 3rd degree block [10]... 

Three patients taking digoxin and either reserpine or whole root Rauwolfia serpentina developed arrhythmias, namely atrial tachyeardia with 4 1 Wenckebach irregular block, ventricular bigeminy and tachycardia, and atrial fibrillation. A large number of other patients received both drugs without problems. ... 

Fig. 9.2 An example of sinus node exit block (Wenckebach type). Progressive slowing of conduction within the sinus node leads to progressive reduction in the atrial rate until there is a long pause owing to blocked...

Haywood GA, Ward J, Ward DE, Cauun AJ. Atrioventricular Wenckebach point and progression to atrioventricular block in sinoatrial disease. Pacing Clin Electrophysiol. 1990 13 2054-2058. 

El-Sherif N, Aranda J, Befeler B, Lazzara R. Atypical Wenckebach periodicity simulating Mobitz type II AV block. Brit Heart J 1978 40 1376-1383. 

Lange HW, Ameisen O, Mack R, Moses SW, Kligfield R Prevalence and clinical correlates of non-Wenckebach narrow QRS complex second degree atrioventricular block detected by ambulatory ECG. Am Heart J 1988 115 114—120. 

The authors of a review of the cardiac toxicity associated with paclitaxel treatment concluded that the overall incidence of serious cardiac events is low (0.1%). The causal relation of paclitaxel to atrial and ventricular dysrhythmias and cardiac ischemia is not entirely clear [32 ]. Reported events include ventricular tachycardia, Mobitz I (Wenckebach syndrome), Mobitz U atrioventricular block, complete atrioventricular block (requiring pacemaker insertion), acute myocardial infarction, supraventricular tachycardia, and atrial fibrillation. 

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