Cardiac cycles & structures/ Dysrhythmias & arhythmias

Question 1

P wave

Answer 1

Action potential starts at SA node,
Atrial depolarization

Question 2

PR segment

Answer 2

Action potential reaches AV node, slowing down to allow atrium to fully contract and ventricles to fully fill w/ blood

Question 3

QRS complex

Answer 3

Ventricular depolarization
Bundle of his, bundle branches, pirkinju fibers

Question 4

T wave

Answer 4

Ventricular repolarization (recovery wave)
Ventricles relax & repolarize

Question 5

Atrial Fibrillation (A-FIB)

Answer 5

Rate: 350-400 bpm
Rhythm: IRREGULARLY, IRREGULAR

S/S: Palpitations, tightness in chest, pulse is bounding, irregular, pacing

TX: Control rate w/ digoxin, CC blockers (verapamil for rapid control)
-Percutaneous or trans thoracic (LIE ON LEFT SIDE)
-Chemical or electrical cardioversion

Question 6

Atrial Flutter (A-flutter)

Answer 6

Rate: 250-400 bpm
Rhythm: P waves are absent, SAWTOOTH PATTERN

S/S: palpitations, SOB, anxiety, weakness, syncope

TX: Slow rate w/ digitalis, beta b’s
-Cardioversion
-Heparin

Question 7

Ventricular Fibrillation (V-FIB)

Answer 7

Rate & rhythm: rapid, unorganized, no p wave

S/S: LOC, no pulse

TX: CPR
-ACLS, code blue, DEFIBRILLATE ASAP!

Question 8

Supraventricular tachycardia (SVT)

Answer 8

Starts at AV node (supra)
Rate & Rhythm: 150-250 bpm, regular

S/S: palpitations, chest discomfort (tight, pressure, pain) SOB, sweating, tightness/fullness in throat, excessive urine production
Pulse: pounding/ fluttering / rapid pulse

TX: Stable (asymptomatic): Valsalva maneuvers (hold breath & bear down, submerge face in cold water, cough forcefully)
Unstable: Adenosine, Cardioversion

Question 9

Ventricular Tachycardia (V-TACH)

Answer 9

Rate: 101-250 bpm
Rhythm: atrial, non distinguishing
No P waves, WIDE QRS COMPLEX

**S/S: palpitations, hypotension, chest pain (angina), SOB, syncope **

TX: Pulse, cardiovert & administer Amiodarone + Lidocaine
No pulse: CPR + ACLS
Chronic recurrent: longterm ICD