P1: SBT
0521779407-05 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 20:49
194 Atrial Premature Complexes
Atrial Premature Complexes............................
EDMUND C. KEUNG, MD
history & physical
History
■Most common cause of an irregular pulse. Often induced by stress,
tobacco, excessive caffeine or alcohol intake. Common in structural
heart diseases.
Signs & Symptoms
■Often asymptomatic. Palpitation and irregular pulse. Rarely, fatigue
and exacerbation of heart failure.
tests
■Basic Tests
➣12-lead ECG:
➣Premature P wave with or without conduction to ventricle
(blocked APC). Premature P wave morphology and P-R inter-
val differ from sinus P wave and conduction. Premature P wave
often masked by preceding T wave. Post-premature pauses usu-
ally non-compensatory
■Specific Diagnostic Test
➣none
differential diagnosis
■Ventricular premature complex, junctional premature complex.
management
What to Do First
■12-lead ECG
General Measures
■Abstin from alcohol and caffeine
specific therapy
■Generally requires no treatment. In symptomatic patients, reassur-
ance, digoxin, beta and calcium channel blocker.
Side Effects & Contraindications
■Excessive suppression of AVN or sinus node activity with beta block-
ers or calcium channel blockers.