Rules for Second Degree Type 1 Block (Wenkebach)
Regularity: The R-R interval is irregular, but there is usually a pattern to it. The R-R interval gets longer as the PRI gets longer. Rate: The ventricular rate is usually slightly higher than the atrial rate due to some atrial beats not being conducted. The atrial rate is usually normal. P WAVE: P waves are upright and uniform. Most copmlexes will have a P wave in front of them, however there will be some that do not have a P wave. PRI: PR interval gets progressively longer until there is a dropped QRS complex. QRS: Measures less than 0.12 seconds.