2) ECG Flashcards
QT interval:
RR interval:
= any action in ventricles
= measuring HR
(ECG Horizontal Boxes) small box is how long
5 small boxes:
Each large box is how long
= 0.04 sec
= 1 large box
= 0.20 sec
(ECG Vertical Boxes) Each small box is & what:
5 small boxes equal:
Each large box is:
2 large boxes equal
= Each small box 1 mm & 0.1mV
= 1 large box
= 0.5 mV & 5mm
= 1mV & 10mm
PRI measured by:
PRI “PR/PRI” interval rep/s:
A normal PRI interval range:
prolonged PRI indicates:
= distance from beginning of P wave to beginning of QRS complex.
= time impulse takes from atria-ventricles “Gatekeeper Gandolf”
= 0.12-0.20 sec / 3-5 SB
= a delay in the AV node & possible HB
QRS interval measured:
QRS interval represents
QRS interval range:
QRS interval Q,R,&S:
= distance from 1st deflection of complex to last deflection
= time needed for ventricle depolarization (bundle of his > ventricles)
= 0.04-0.12secs / 1-3SB
= 1st -deflection not >1SB, 1st +deflection, -deflection after R
T wave represents:
T wave amplitude:
= Repolarization of ventricles
= <5mm in LL <10mm in precordial
Absolute refractory period:
Relative refractory period:
= Apex of T wave Q-T wave apex of wave: ventricle not ready to work
= T wave top to end of T wave: (commodo cordis) cells not repolarized (torsades de pointes more dead from repolarization not in sync)
who 1st noted skeletal M.s are excitable by shocking frogs:
who Pub/ed 1st ECG using a capillary metter w/ salt water:
= 1786 Dr. Luigi Galvani> “Muscle contract w/ elect”
= 1821, Augustus Waller > (couldn’t recreate same impinge)
1786 Dr. Luigi Galvani:
1821, Augustus Waller:
= 1st noted skeletal muscles were excitable by shocking frogs “Muscle contract w/ elect”
= Pub/ed 1st ECG using a capillary metter w/ salt water (couldn’t recreate same impinge)
Resting potential of the cardiac contractile cell occurs at:
Action potential of the cardiac contractile cell occurs at:
What ion causes the cardiac contractile cell to depolarize?
What ion causes the cardiac contractile cell to repolarize?
= -90mV
= -85mv
= Sodium
= Potassium
A normal QRS has a duration between:
A normal PRI has a duration between:
= 0.04-0.12 secs / 1-3SB
= 0.12 - 0.20 secs/ 3-5SB
On ECG paper, one small vertical box represents:
On ECG paper, one large vertical box represents:
= 0.1mV/ 1mm
= 0.5mV/ 5mm
Purkinje System has an inherent firing rate of:
AV Node has an inherent firing rate of:
SA Node has an inherent firing rate of:
= 15-40BPM
= 40-60BPM
= 60-100BPM
Natural pacemaker of the heart is:
If SA Node failed to initiate a impulse, what is 1st back-up firing site?
If both SA & AV fails what is last firing site:
= SA node
= AV node
= Purjunkie
impulse traveling towards a positive electrode will produce a:
Impulse traveling away from a positive electrode will produce a:
= positive deflection wave ECG
= negative deflection wave ECG
Action potential of autorhythmic cell occurs at:
Resting potential of autorhythmic cell occurs at:
ion causes autorhythmic cell to depolarize:
ion causes autorhythmic cell to repolarize:
= -40mV
= -60mV
= Calcium
= Potassium
The SA Node is found where in the heart?
The AV Node is found where in the heart?
Purjunkie System found where in the heart?
= Upper right of atrium
= In the lower right of atrium
= Septum to bottom of ventricles
Cardiac cell communication w/ ions
Phase 0 of the cardiac contractile cell:
Phase 1 of the cardiac contractile cell:
Phase 2 of the cardiac contractile cell:
Phase 3 of the cardiac contractile cell:
Phase 4 of the cardiac contractile cell:
= gab junction & intercalated disc 400x faster
= P0) Depolarization
= P1) slow K efflux
= P2) Plateau> Slow Ca in & K out “- for +”
= P3) Repolarization> rapid K efflux
= P4) Refractory Na/K pumps & Ca pumps out
What does the P wave represent on an ECG:
What does the T wave represent on an ECG:
What does the QRS wave represent on an ECG:
= Arterial depolarization
= Ventricular depolarization
= electrical activity in ventricles