 Any
atrial area may originate an impulse.
 Rhythms have upright P waves preceding
each QRS complex.

Not as well-rounded
 Heart
rates usually from 60 to
100 beats/min
 Atrial



flutter
Atria contract too fast for ventricles to match
Resemble a saw tooth
F waves get blocked by AV node, creating several
F waves before each QRS complex
 Atrial




flutter (cont’d)
Caused by hypertension, coronary artery disease,
and cardiomyopathy .
frequently degenerates into atrial fibrillation .
Symptoms include shortness of breath, chest
pains, lightheadedness or dizziness, nausea and,
in some patients, nervousness and feelings of
impending doom.
Treatment is usually medication or electrical
cardioversion.
 Atrial


fibrillation
Atria fibrillate or quiver
Random depolarization from atria cells
depolarizing independently
Adapted from Arrhythmia Recognition: The Art of Interpretation, courtesy of Tomas B. Garcia, MD.
 Atrial




fibrillation (cont’d)
Irregularly irregular appearance .
Usually signs of serious heart problem .
Tendency to cause clots .
Prehospital treatment is rare.
 paroxysmal
supraventricular tachycardia
(SVT)





Called paroxysmal SVT (PSVT) because of
tendency to begin and end abruptly
Tachycardic rhythm from pacemaker
Regular rhythm, rate exceeding 150 beats/min
QRS complexes: 40 to 120 ms.
May have cannon “A” waves
Adapted from Arrhythmia Recognition: The Art of Interpretation, courtesy of Tomas B. Garcia, MD.
 Premature


atrial complex
A particular complex within another rhythm
Upright P wave precedes each QRS complex
Adapted from Arrhythmia Recognition: The Art of Interpretation, courtesy of Tomas B. Garcia, MD.
 Premature


atrial complex (cont’d)
Non-conducted PAC: P wave occurs early on the
ECG and is not followed by a QRS complex.
PACs occur when another region of the atria
depolarizes before the sinoatrial node and thus
triggers a premature heartbeat.
 Wandering

atrial pacemaker
Wandering pacemaker is usually caused by
varying vagal tone . With increased vagal tone
the SA Node slows, allowing a pacemaker in the
atria or AV Nodal area, which may briefly become
slightly faster. After vagal tone decreases, the SA
Node assumes its natural pace.Upright P wave
precedes each QRS (at least
3 shapes of P waves within a strip)
 Wandering

atrial pacemaker (cont’d)
Most common with significant lung disease
 Multifocal



atrial tachycardia (MAT)
Pacemaker moves within various atrial areas
Rate of more than 100 beats/min
Upright P wave preceding each QRS complex

P waves vary.
 Multifocal



atrial tachycardia (cont’d)
PR interval: 120 to 200 ms
Most common with significant lung disease, but it
can occur after acute MI, hypokalemia, and
hypomagnesemia
Therapies for SVT generally ineffective
 The
P-waves and P–R intervals are variable
due to a phenomenon called wandering atrial
pacemaker (WAP).
 Then, if the heart rate exceeds 100 beats per
minute, the phenomenon is called multifocal
atrial tachycardia.