QUESTIONS AND ANSWERS SURE A+
✔✔Block in HPS at an H1-H2 interval greater than 400 ms would be - ✔✔indication for
pacer
✔✔Autonomic maneuvers would do what to the refractory of AVN - ✔✔Decrease
✔✔Approximately what % of patients with SA nodal disease also have AV conduction
disease - ✔✔33%
✔✔Most characteristic of automatic tachycardia - ✔✔non-inducible
✔✔What is most necessary for initiation of a reentrant SVT - ✔✔Slow pathway,
unidirectional block
✔✔SVT rhythm characterized by afterpotentials and cycle length being key initiators -
✔✔Triggered
✔✔Two of the most common automatic arrhythmias - ✔✔Nonparoxysmal junctional and
atrial
,✔✔T of F: there is typically a conduction delay when a reentry tachycardia is initiated -
✔✔True
✔✔T or F: The tachycardia zone is the range of intervals of premature beats that will
initiate reentrant tachycardias - ✔✔True
✔✔T or F: the atrium is a critical part of the circuit in AN nodal entry tach - ✔✔False
✔✔The critical portion of the circuit in intra-atrial reentry tach involves - ✔✔Atrial
myocardium
✔✔SA nodal reentry is distinguished from sinus tach by its - ✔✔paroxysmal onset and
termination & inducibility and termination by pacing
✔✔Retrograde P waves
Negative P waves in inferior
RP<PR - ✔✔Bypass tract mediated tach
✔✔Bypass tracts electrophysiologically behave most like - ✔✔Myocardial tissue
✔✔Pharmacologic treatment for rate control of Afib often includes - ✔✔Digoxin & beta
blocker
✔✔T or F: Patients w/ bypass tracts are more prone to AFL and AF - ✔✔True
✔✔T or F: the atrium may take hours to days to contract following cessation of AFib -
✔✔True
✔✔T or F: AFib requires a critical mass of contiguous myocardium to propagate itself -
✔✔true
✔✔Approximate number of American that suddenly die each year - ✔✔400,000
✔✔Which arrhythmia type (automatic, reentrant, triggered, outflow): Also termed
"repetitive monomorphic VT) - ✔✔Outflow
✔✔Which arrhythmia type (automatic, reentrant, triggered, outflow): non-inducible,
younger pts w/o heart disease often provoked by exercise - ✔✔Outflow
✔✔Ohm's Law - ✔✔V=IR
✔✔Energy
-definition
,-unit
-formula - ✔✔-Ability to do wok
-Joule (J)
J= V x I x t = (V^2/R)t
✔✔Power
-definition
-unit
-formula - ✔✔-Quantity of energy applied per unit of time
-Watt (W)
W = J/t = V x I
✔✔Voltage - ✔✔Electrical pressure or electromotive force causing current to flow
✔✔Current - ✔✔Flow of electrons or ions
1 Amp = 1 coulomb/sec
✔✔Resistance - ✔✔Opposition to current flow
✔✔(-) signal deflection indicates signal is moving away from _____ towards _______ -
✔✔(-) signal deflection indicates signal is moving away from (+) towards (-)
✔✔(+) signal deflection indicates signal is moving away from _____ towards _______ -
✔✔(+) signal deflection indicates signal is moving away from (-) towards (+)
✔✔biphasic signal deflection indicates signal is moving _______ - ✔✔biphasic signal
deflection indicates signal is moving perpendicular
✔✔High pass & low pass filter settings for ECG - ✔✔0.5 Hz
100 Hz
✔✔High pass & low pass filter settings for intracardiac - ✔✔30-40 Hz
400-500 Hz
✔✔1st deg heart block - ✔✔A condition of abnormally slow conduction through the AV
node. It is defined by ECG changes that include a PR interval of greater than 0.20
without disruption of atrial to ventricular conduction.
PR > 200 msec
✔✔2nd deg heart block type 1 - ✔✔Wenckebach - electrical signals get slower & slower
until a beat eventually skips
✔✔2nd deg heart block type 2 - ✔✔Some electrical signals get to ventricles and some
don't
, ✔✔3rd deg heart block - ✔✔Electrical signals do not go from Atria to Ventricles at all
✔✔Signal Average ECG
-uses
-values (HFQD, LAS, RMSA) - ✔✔Looks for late potentials in pts vulnerable to
Sustained VT (pts post MI)
Normal Ranges
-HFQD: <110-114
-LAS for QRS <40 uV: <30-38ms
-RMSA: >20-35uV
(+) result = 2/3 abnormal
✔✔2 types of ICE - ✔✔-Radial (Boston Scientific)
-Phased Array (BWI)
✔✔T Wave Alterna (TWA)
-uses
-pitfalls
-most significant result - ✔✔SCD risk stratifier
Measures microscopic changes in T wave amplitude on beat by eat basis
Criteria
-HR must exceed 110 bpm
-<10% ectopic beats, low noise, absence of AF
1/4 of TWA are indeterminate due to failure to meet criteria
If test is (-) 99% predictive probability where as (+) only has 20% predicative probability
✔✔Vasodepressor Tilt Table Response - ✔✔HR increases progressively & does not fall
more than 10% from peak at time of syncope
BP decreases dramatically to cause syncope
✔✔Cardio-inhibitory Tilt Table Response - ✔✔HR increases initially then falls to <40
bpm for more than 10 sec or asystole >3 sec
BP increases initially and then falls
✔✔Mixed Response Tilt Table Response - ✔✔HR increases initially then falls but not
<40 bpm (or if <40 bpm, not for more than 10 sec)
BP increases initially and then falls before HR drops
Most common response
✔✔Tilt Table result benefiting from PPM - ✔✔Cardio-inhibitory
✔✔Drugs used in Tilt Table Testing - ✔✔Isuprel
Nitroglycerin (powerful vasodilator which enhances venous pooling)