3) Sinus Rhythms Flashcards
Rhythm initiated by SA node should have a rate between:
Sinus Tachycardia has a heart rate of:
Sinus Bradycardia has a heart rate of:
= 60-100 beats per minute
= 101 & >BPM
= 59 &<BPM
ECG rhythm w/ following} SA node fails to initiate an impulse, multiple dropped beats, & cadence is thrown off when starts back is:
Sinus Arrest
Which ECG component represents atrial depolarization?
Which ECG component represents ventricular depolarization?
Which ECG component represents ventricular repolarization?
= P wave
= QRS Complex
= T Wave
Vaughan-Williams Classification scale, Calcium channel blocker is a:
Vaughan-Williams Classification scale, Sodium channel blocker is a:
Vaughan-Williams Classification scale, Potassium channel blocker is a:
Vaughan-Williams Classification scale, a Beta-Blocker is a:
= Class IV Antiarrhythmic
= Class I Antiarrhythmic
= Class III Antiarrhythmic
= Class II Antiarrhythmic
If PRI >0.20 seconds, what is occurring in electrical conduction system:
= electrical impulse is being held too long at the AV node.
In any limb lead, a normal P wave shape & maximum amplitude is:
In any chest lead, a normal P wave has maximum amplitude of:
= nice & round w/ maximum amplitude of: 0.25 mV
= maximum amplitude of: 0.15 mV
The period of an ECG that is most vulnerable to an ectopic beat causing the patient to go into a lethal rhythm is known as the:
= Relative Refractory Period (& its segmentation)
1st step when deciphering an ECG rhythm is:
2nd step when deciphering an ECG rhythm is:
3rd step when deciphering an ECG rhythm is:
4th step when deciphering an ECG rhythm is:
5th step when deciphering an ECG rhythm is:
= To calculate the heart rate
= Determine if the rhythm has a normal or abnormal cadence
= Evaluate the P Waves
= Measure the PR Interval
= Evaluate the QRS complexes
Normal T Wave in any limb lead should have a max amplitude of:
Normal T Wave in any chest lead should have a max amplitude of:
= 5 mm
= 10 mm
ECG rhythm w/ following} impulse fails to leave SA node, multiple dropped beats, but cadence is right on track when it starts back up is:
= Sinus Block
A normal PRI should be between
A normal QRS duration should be between:
= 0.12-0.20 seconds
= 0.04-0.12 seconds.
Rapid influx of what ion causes an autorhythmic cell to depolarize:
Rapid influx of what ion causes a cardiac contractile cell to depolarize:
Efflux of what ion causes both types of cardiac cells to repolarize:
= Calcium
= Sodium
= Potassium
Class IV Antiarrhythmic of Vaughan-Williams Class is:
Class I Antiarrhythmic of Vaughan-Williams Class is:
Class III Antiarrhythmic of Vaughan-Williams Class is:
Class II Antiarrhythmic of Vaughan-Williams Class is:
= Calcium channel blocker
= Sodium channel blocker
= Potassium channel blocker
= Beta-Blocker
ECG rhythm w/ following} SA node fails to initiate an impulse, only 1 dropped beat, Cadence is thrown off when starts back up is:
= Sinus Pause
(ECG Paper) (Horizontal Boxes) small box duration:
5 small boxes makes:
Each large box duration:
(Vertical Boxes) Each small box volt & measurement:
5 small boxes makes:
Each large box voltage:
2 large boxes equivalent:
= 0.04 sec
= 1 large box
= 0.20 sec
= 0.1 mV & 1 mm
= 1 large box
= 0.5 mV
= 1 mV & 10mm
ECG originating from SA node is producing a rhythm that has 15 small boxes in-between R-R intervals. You would recognize this ECG has a heart rate of:
= 100 beats per minute
ST segment:
QT segment:
U wave:
P-T segment:
RR segment:
= Ventricle contraction
= Any action in ventricles
= “late bloomer”
= 1 cardiac cycle
= provides Rate & Rhythm
(P wave) morphology:
represents:
Limb Lead amplitude
Precordial “chest” Leads amplitude:
= + deflection in leads 1,2,&3 >Biphasic in V1
= Atrial depolarization
= <2.5
= <1.5
(Refractory periods) Absolute:
Relative:
= end of P to apex of T wave- cells absolute Beginning of repolarization
= “some really could happen” lot of cells repolar but not all so can throw out of rhythm Commodo cordis
Synchronized cardioversion:
= shock not in relative refractory period
(QRS complex) morphology Q,R,S waves:
Interval duration:
Represents:
= 1st neg deflection, 1st + deflection, neg deflection following R
= 0.04 - 0.12 secs (1-3 SB)
= Ventricles depolarization
(T wave) morphology:
Represents:
Duration:
Limb lead amplitude:
Precordial “chest” lead amplitude:
= + deflection, asymmetric w/ deeper downslope
= Ventricle repolarization
= QT variable calculation ()
= <5mm
= <10mm
Triplicate method:
6 sec method:
R to R small box method:
R to R big box method:
= for HR> Big box RR descends 300,150,100,75,50,50,43,38
= Count # of complexes in a 6-sec strip X 10
= Count small boxes between R waves then /1500 EX: 1500 / 22 = 68
= (only regular rhythm) Count big boxes between R waves then divide 300 by this number EX 300 / 4 = 75
(Arrhythmias) causes: 1.
2.
3.
4.
5.
6.
7.
8.
1.= Blood gas abnormalities (hypoxia & abnormal pH (haldane & Bohr)
2.= Electrolyte imbalances (Ca++, K+, Mg++)
3.= Trauma to myocardium
4.= Drug effects / toxicity
5.= Digoxin- can cause multitude of dysfunctions
6.= Myocardial ischemia, necrosis, infarction,
7.= ANS imbalance
8.= Chamber/s Distention
Digoxin-
= can cause any prescribed for CHF Restrict refractory K/Na pumps
(Electrolytes affects) Cl
Na
K
Ca
Mg
= Cl picks up Co2 (shift) to keep neutrality
= depolarizing myocardium
= depolarization & majority myocardial contractile
= influences repolarizations
= regulates contractility & rhythm
(Arrhythmias) Mechanism of Impulse Formation Ectopic foci:
= Enhanced automaticity; automatically depolarize, producing ectopic (abnormal) beats.
PAC PJC PVC
= premature atrial,junctional,ventricular contractions
Hypothermia affect on heart:
= Osborn waves (J waves), <90 core usually, So irritable will/can throw to AFIB
(Arrhythmias) Mechanism of Impulse Formation of Reentry:
= Isolated premature beats, or tachyarrhythmias; alters 2 branches of
conduction pathways> 1 branch slows thus unidirectional block
(Sinus Bradycardia) Rhythm Etiology:
Drug effects:
= Increased parasympathetic tone, Intrinsic SA node disease (old),
= digitalis, beta- blockers, calcium channel blockers
(Sinus Bradycardia) conduction etiology:
= typically all WNL besides rate, Impulse arises from the SA node
(Sinus Bradycardia) Symptomology “signs”:
Treatment:
If signs of poor perfusion:
= Decreased CO & BP, angina, CNS symptoms
= Atropine if needed symptomaticly stable PT, transcutaneous pacing
= prepare for transcutaneous pacing.
Cardiac always Dos & Knows} 1.
2.
3.
4.
5.
6.
7.
8.
1.= investigator for underlying etiology
2.= 50% syncope’s cardiac related
3.= look/know underlying symptoms before ANY MED ADMIN
4.= 220-age= THR withstanding
5.= SYSTEMATIC APPROACH
6.= if don’t know call pro (cardiologist/DR)
7.= Majority of MIs inferior wall w/ RCA
8.= more time to pacing = more ineffective
(ECG inturp/) Arrhythmia
= inconsistent RRs, possibly no/lil P waves, all other intervals WNL
(ECG inturp/) Sinus Bradycardia) definer:
Rhythm:
P waves & PRIs:
Pacemaker site:
QRS Complexes:
= <60BPM
= Regular Rhythm typically
= Present & normal, all followed by QRS complex, PRI: WNL
= SA Node typically
= Normal morphology & WNL
(ECG inturp/) w/ Sinus Pause) definer:
Rate & Rhythm:
P waves & PRIs:
Pacemaker site:
QRS Complexes:
= Drop beat out of cadence & only 1 drop beat! “SA paused”
= normal or Brady & Regular Rhythm typically
= Present & normal, all followed by QRS complex, PRI: WNL
= SA Node
= Normal morphology & WNL
(ECG inturp/) Sinus Tachycardia) definer:
Rhythm:
P waves & PRIs:
Pacemaker site:
QRS Complexes:
= 101 or more BPM “sharp narrow arrows”
= Regular Rhythm
= Present & normal, all followed by QRS complex, PRI: WNL
= SA Node
= Normal morphology & WNL
(ECG inturp/) w/ Sinus Block) definer:
Rhythm:
P waves & PRIs:
Pacemaker site:
QRS Complexes:
= “flatline in cadence” SA node fires on time but impulse blocked
= Irregular Rhythm
= Present & normal, all followed by QRS complex, PRI: WNL
= SA Node
= Normal morphology & WNL
(ECG inturp/) w/ Arrest) definer:
Rhythm:
P waves & PRIs:
Pacemaker site:
QRS Complexes:
= “Sinus pause on steroids”, large standstill, >1 drops
= Irregular Rhythm
= Present & normal, all followed by QRS complex, PRI: WNL
= SA Node
= Normal morphology & WNL
Sinus Block) Conduction:
Causes:
= SA node firing blocked for period, thus a brief cardiac “Hold”
= Ischemia of SA node, Digitalis toxicity, Excessive vagal tone, Degenerative fibrotic disease (getting old)
Sinus Pause) Conduction:
Causes:
= SA node fails to discharge for brief period, thus missing 1 PT seg/
= Ischemia of SA node, Digitalis toxicity, Excessive vagal tone, Degenerative fibrotic disease (getting old)
Sinus Arrest) Conduction:
Causes:
= Fails to discharge for period, thus a of cardiac standstill.
= Ischemia of SA node, Digitalis toxicity, Excessive vagal tone, Degenerative fibrotic disease (getting old)
Sick Sinus Syndrome:
Rhythm Etiology:
Causes:
S/S:
Treatment:
= “ICU death bed multiorgan fail/dysfunction”: organs dying b/c lacking perfusion, Very rare, Pre cursor to death, No P / beat
= Not arrhythmia per se; combo of arrhythmias; Wild swings in HR,
= SA node diseased or ischemic, Digoxin toxicity, getting old
= Frequent or prolonged episodes may comp/ CO resulting in syncope.
= If signs of poor perfusion, prepare for transcutaneous pacing.
Normal QRS duration:
Normal PRI duration:
= 0.04 - 0.12 seconds
= 0.12 - 0.20 secs
When using lead III – where is the positive lead placed?_Left leg.
When using lead II – where is the positive lead placed? Left leg
When using lead I – where is the positive lead placed? Left Arm
When using lead III – where is the negative lead placed? Left arm.
When using lead II – where is the negative lead placed? Right arm
When using lead I – where is the negative lead placed? Right Arm
When using lead I –where is the negative lead placed?Right arm
= Left leg
= left leg
= left arm
= left arm
= right arm
= right arm
= right arm
1st negative deflection following the R wave is the:
What wave on ECG represents repolarization of the ventricles:
The first negative deflection following the P wave is the:
What wave on ECG represents depolarization of ventricles:
1st positive deflection following the P wave is:
What wave on an ECG represents depolarization of the atriums:
= S wave
= T wave
= Q wave
= QRS wave
= R wave
= P wave
What is considered the normal max amplitude of a P wave in lead II?
What is considered the normal max amplitude of a P wave in lead V1?
= 2.5mm
= 1.5mm
When obtaining a 12 lead ECG, where do you place V2?
When obtaining a 12 lead ECG, where do you place V5?
When obtaining a 12 lead ECG, where do you place V6?
When obtaining a 12 lead ECG, where do you place V3?
When obtaining a 12 lead ECG, where do you place V1?
When obtaining a 12 lead ECG, where do you place V4?
When obtaining a 15 lead ECG, where do you place V4R?
= 4th ICS just left of Sternum
= Left 5th ICS anterior of auxiliary
= 5th ICS midaxillary
= ½ in between V2 & V4
= Right of Sternum 4th ICS
= 5th ICS left Midclavicular
= Right ICS midclavicular
1st step an EMS provider will take when deciphering an ECG rhythm?
2nd step an EMS provider will take when deciphering an ECG rhythm?
3rd step an EMS provider will use when deciphering an ECG rhythm?
4th step an EMS provider will take when deciphering an ECG rhythm?
5th step an EMS provider will take when deciphering an ECG rhythm?
= Calculate HR
= Determine if rhythm has normal cadence
= P waves
= Measure PRI
= Evaluate the QRS complexes
If SA node initiates an impulse & traveled through atriums via normal pathways, this would create what type of P wave in Lead I
= it should create an upright P wave
What’d happen to autorhyth/cell if admin/ Ca-channel blocker to PT?
= It would cause a decrease in the PTs BP
The period of an ECG that is most vulnerable to an ectopic beat causing the patient to go into a lethal rhythm is known as the:
= Relative Refractory Period
The RP of a myocardial contractile cell is how many mV’s:
The AP of a myocardial contractile cell is how many mV’s:
What channels in cardiac contractile cells bring about depolarization:
When cardiac contractile cell starts to repolarize – what ion is leaving:
= -90mV
= -85mV
= Voltage gated Na channels
= Potassium
med classified as “parasympatholytic” will have what effects on body?
med classified as “sympathomimetic” will have what effects on body:
= indirect SNS positive effects(cuts PSNS for SNS to indirectly to take over): positive tropic effects, + SNS effects, cuts PSNS & it’s effects
= mimics SNS: +tropic effects, vasoconstriction, bronchodilation, +A&B
What channels in the autorhythmic cells bring about depolarization:
The AP of an autorhythmic cell is how many mV’s
The RP of an autorhythmic cell is how many mV’s
what ion effluxes out of the cell membrane during repolarization:
= Ca channels
= -40mV
= -60mV
= Potassium
During the diastolic phase, what valves inside of the heart are closed?
During the systolic phase, what valves inside of the heart are closed?
= Pulmonic & Aortic
= Bi & Tricuspid
What is considered the normal max amplitude of a T wave in lead I?
What is considered the normal max amplitude of a T wave in lead V1?
= 5mm
= 10mm
Which part of the heart has the most muscle:
Oxygenated blood returns to left atrium via:
Blood cell travels from L-ventricle, through what valve & into What:
Deoxy/ blood travels from R-ventricle to lungs through what:
= Left Ventricle
= Pulmonic Vein
= Aortic valve & aorta
= Pulmonic artery
Usually only norm/ path for impulse to travel @ R-atrium to ventricles:
most correctly illustrates what a normal T Wave should look like?
= Via AV node
= should be slightly asymmetric w/ steeper downslope than upslope
Biphasic:
= “above & below” isoelectric line
ACS acute coronary syndrome
PVC premature ventricular
= “general broad title to book”
= “im tired of waiting screw you i’m firing”
minimum for ST elevation
= 2.5mm/0.25mV
ST depression >than:
= 2mm/0.2mV
QT interval:
RR interval:
= any action in ventricles
= measuring HR
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
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)
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
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
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
Normal ECG paper speed is
On ECG paper, 1 Small horizontal box represents:
On ECG paper, 1 Large horizontal box represents
= 25mm/sec
= 0.04 secs
= 0.20 secs
Cardiac artifacts:
Causes of artifacts:
= hard to decipher iso-electrical lines w/ 0 & skewed
= M. tremors/shivering, PT mnt(moves baseline), Loose electrodes, 60-hertz interference(ungrounded electricity near you (AC current alternating in house), Machine malfunction (Dotted flat line),& electrode bad connection/ off
Eintovhens triangle (bipolar) camera always at
L1 + & - leads:
L2 + & - leads:
L3 + & - leads:
= positive > Bipolar - to +
= -RA to +LA
= -LL to + LL
= -LL to + LL
Unipolar leads:
Unipolar lead camera:
aVR:
aVL:
aVF:
= 1 polarity(need 4 LL): AvR,LvR, (Wilson’s central terminal)
= Starts at middle point of lines look to center terminal
= augmented voltage right (right (looks at R-atrium)
= augmented voltage Left Positive Left arm +, L-wall
= augmented voltage Foot: Left Leg positive inferior
Precordial “chest” leads:
V1 location:
V2 location:
V3 location:
V4 location:
V5 location:
V6 location:
V ”5” 8 location:
V ”6” 9 location:
=
= V1: 4th ICS R of sternum
= V2: 4th ICS L of sternum
= V3: ½ in between
= V4: 5th ICS mid-clavicularly
= V5: 5th ICS anter auxillary
= V6: mid auxillary
= V ”5” 8: 5th ICS mid scapular
= V ”6” 9: ½ between spine & midscapular
(Limb leads) placement:
positive to negative makes wave:
positive to negative makes wave:
= mid forearm on M. & inside of calf (if amputee/ go less distally)
= positive wave
= negative wave
!!Starling’s Law of heart:
= states that the more the myocardium is stretched, up to a certain amount, the more forceful the subsequent contraction will be
(Einthoven’s triangle) Negitive & Positive lead 1 sites:
Negitive & Positive lead 2 sites:
Negitive & Positive lead 3 sites:
=negative @ RA & positive @ LA
= negative @ RA & positive @ LL
= negative @ LA & positive @ LL
Precordial “Chest” leads help in viewing:
L-ventricle & septum.
prolonged QT interval related to:
= increased risk of certain ventricular arrhythmias & sudden death. Numerous meds, (particularly some antipsychotics)
(leads veiws) I and aVL:
II, III, and aVF:
aVR:
V1 and V2:
V3 and V4:
V5 and V6:
= Left side of the heart in a vertical plane
= Inferior (diaphragmatic) side of the heart
= Right side of the heart in a vertical plane
= Right ventricle
= Interventricular septum and the anterior wall of the left ventricle
= Anterior and lateral walls of the left ventricle
!!Poiseuille’s law:
Example:
= vessel w/ relative radius of 1 would transport 1mL per min at BP difference of 100mmHg. Keep pressure constant
= Less blood = vaso-press
Ejection Fraction (EF):
<45% usually indicates:
<30%:
= Ratio of blood pumped from the ventricle to the amount remaining @ the end of diastole/ %of blood pumped out from ventricle (60-70%)
=<45% usually indicates in or going to CHF
=<30% in CHF & chronic cardiac crip on oxy
Preload:
= pressure (volume) w/in the ventricles at the end of diastole & Also commonly called the end diastolic volume (frank starlings law)
Afterload:
= resistance against which the heart must pump against afterload become increased w/ increased ventricular workload
Stroke volume:
3 factors that affect stroke volume:
= amount of blood ejected by heart in 1 contraction, varies 60-100mLs w/ average 70mL
= preload, afterload, & contractility
(only in heart) Intercalated discs:
Discs speed Vs standard cell membrane:
Syncytium:
= Special tissue bands inserted between myocardial cells that increase the rate(400x) in which AP is spread from cell-cell thus Syncytium
= 400x faster than standard cell membrane drom/Inotropy
= Group of cardiac cells physiologically function as a unit, “working together in sync” “top in syncytium to bottom”
(Einthoven’s triangle(Bipolar/limb leads) leads 1 views:
Lead 1 Negative:
Lead 1 Positive:
= Left Lateral wall
= Right Arm
= Left Arm
(Einthoven’s triangle(Bipolar/limb leads) leads 2 views:
Lead 2 Negative:
Lead 2 Positive:
= Inferior wall diagonally towards left foot
= Right Arm
= Left Leg
Which coronary artery feeds the inferior wall of the heart?
Right Coronary Artery (RCA)
Which coronary artery feeds the left lateral wall of the heart?
Left Circumflex (LCX)
A blockage of which of the following would result in the entire left ventricle not receiving blood supply?
Left Main Coronary Artery (LMCA)
Communication or the connecting of two or more vessels is known as:
= Anastomosis
Most common dysrhythmia
= Atrial Fibulation
