AV Blocks

Question 1

Blocks are?

Answer 1

partial or complete interruption in conduction b/w atria and vents

Question 2

1º AV Block is?

Answer 2

consistent delay at AV node,
not true block,
(U) insignificant

Question 3

1º AV Block findings:

Rate?

Rhyth?

P-wave?

PR Interval?

QRS?

QT Interval?

Answer 3

Rate = any

Rhyth = regular

P-wave = normal

PR Interval = LONG / CONSTANT

QRS = normal

QT Interval = normal

Question 4

2º AV Block Type I is?

Answer 4

(“Wenckebach”) intermittent block at AV node,
(U) reversible,
if frequent QRS dropping -> sxs of ↓ CO

Question 5

2º AV Block Type I findings:

Rate?

Rhyth?

P-wave?

PR Interval?

QRS?

QT Interval?

Answer 5

Rate: Atrial = normal, Vent = any

Rhyth =patterned irregular

P-wave = normal, not always followed by QRS

PR Interval = PROGRESSIVELY LONGER until QRS DROPPED, cycle REPEATS

QRS = normal

QT Interval =normal

Question 6

2º AV Block Type II is?

Answer 6

intermittent block at HIS/branches ->
atrial impulses don’t reach vents

serious -> ↓ CO

Question 7

2º AV Block Type II findings:

Rate?

Rhyth?

P-wave?

PR Interval?

QRS?

QT Interval?

Answer 7

Rate: Atrial = normal, Vent = any

Rhyth = reg or irregular

P-wave = normal, more P-waves than by QRS

PR Interval = PROLONGED/CONSTANT

QRS = normal, intermittently dropped

QT Interval =normal

Question 8

3º AV Block is?

Answer 8

complete block at or below AV node,
no atrial impulses reach vent,
vent pacemakers take over (escape)

tolerated if escape rhythm maintains CO

Question 9

3º AV Block findings:

Rate?

Rhyth?

P-wave?

PR Interval?

QRS?

QT Interval?

Answer 9

Rate: Atrial = normal, Vent = any

Rhyth = Atrial and Vent regular but NOT RELATED to ea other

P-wave = normal (march out)

PR Interval = not measurable

QRS = normal if escape is jxnl, wide if escape is ventral

QT Interval = normal or abnormal