arrythmias

Question 1

gradual onset/termination, P wave identical to NSR

Answer 1

sinus tach

Question 2

HR <55-60bpm

Answer 2

brady

Question 3

1. inappropriate sinus bradycardia
2. Alternating bradycardia & atrial tachyarrhythmias (tachy-brady syndrome)
3. Sinus pause/arrest: sinus pause >3s = sinus arrest (+/- escape rhythm)
4. SA nodal exit block

Answer 3

SND

Question 4

Block occurs IN the AV node:

Answer 4

▪︎first-degree
▪︎second-degree Mobitz type I (Wenckebach)

Question 5

prolonged PR interval (>200ms)

Answer 5

first-degree AV block

Question 6

Block occurs BELOW the AV node:

Answer 6

▪︎second-degree Mobitz type II
▪︎third-degree (complete heart block)

Question 6

progressively longer interval followed by non-conducted P

Answer 6

Second-degree, Mobitz I (Wenckebach):

Question 7

NO atrial impulses reach ventricles; complete dissociation between P waves & QRS complexes

Answer 7

▪︎third-degree (complete heart block)

Question 8

random dropped QRS, stable PR

Answer 8

Second-degree, Mobitz II

Question 9

*ONE irritable atrial focus causing atrial depolarization
– sudden onset/termination
*circuit usually initiated by PAC

Answer 9

a flutter

Question 10

atrial rate ~300bpm, ventricular rate ~150bpm

Answer 10

a flutter

Question 11

absence of discrete P waves ⇢ replaced by small, rapid, continuously varying
fibrillatory waves oscillating at 350-600bpm

Answer 11

a fib

Question 12

narrow QRS, retrograde P wave after QRS, ⊖delta wave

Answer 12

Orthodromic AVRT

Question 13

wide QRS, ⊕ delta wave, P wave rarely visible

Answer 13

antidromic AVRT

Question 14

fast & slow pathways in AV node; often trigged by PAC

Answer 14

AVNRT

Question 15

reentry mechanism via bypass tract between atria/ventricles,

Answer 15

AVRT

Question 16

premature beat followed by a normal QRS, P wave has different morphology from sinus P wave

Answer 16

PAC

Question 17

premature wide QRS w/o preceding P wave followed by full compensatory pause

Answer 17

PVC

Question 18

≥3 PVCs =

Answer 18

nonsustained VTACH

Question 19

*regular, broad complex tachycardia
*uniform QRS complexes within each lead (i.e., each QRS is identical)

Answer 19

monomorphic VT

Question 20

hereditary, characterized by structurally normal heart
*associated w/ ventricular dysrhythmias ⇢ syncope & sudden cardiac death
– d/t mutation in cardiac Na gene channel (“sodium channelopathy”)

Answer 20

brugada

Question 21

pseudo-RBBB + persistent ST segment ⇡ (coved) in V1-V2

Answer 21

brugada

Question 22

*total disorganized ventricular depolarization
*ventricle impulse rates up to 500bpm
*total loss of synchronized ventricular contraction, complete loss of CO

Answer 22

vfib

Question 23

chaotic irregular zigzag pattern of varying amplitude
▪︎no identifiable P waves or QRS complexes, rates varying between 150-500bpm
▪︎as times passes, amplitude typically decreases (coarse ⇢ fine)

Answer 23

vfib

Question 24

broad, notched, or slurred R waves (rR’/RR’) in leads I, aVL, V5/V6
▪︎dominant S wave in lead V1

Answer 24

LBBB

Question 25

terminal R wave in V1/V2 (rSR’) w/ discordant ST/T waves

Answer 25

RBBB