The P wave represents the depolarization of the atria. The P-R interval represents depolarization of the atria, atrioventricular (AV) node, bundle of His, bundle branches, and the Purkinje fibers. The QRS represents ventricular depolarization. The Q wave is the first negative deflection following the P wave and should be narrow and short.
DIF: Cognitive Level: Understand (comprehension) REF: 791
TOP: Nursing Process: Assessment MSC: