Upgrade to remove ads
Only $35.99/year

ECG's

Terms in this set (50)

P wave (3)
-Arial depolarization and contraction
-less then .1 sec
-pumping blood into ventricles
PR segment (1)
AV node holds impulse
QRS interval (2)
-ventricular depolarization and contraction
-.04-.1 sec
T wave (2)
-ventricular repolarization
-rest
U wave (1)
-happens sometimes. norm with hypertension, K or Mg imbalance
PR interval (2)
-time it takes for the impulse to travel from atria through the AV node, bundle of his and bundle branches
-.12-.2 sec (3 blocks)
U wave (2)
-may represent purkinki fiber repolarization
- may indicate hypokalemia
J point
marks the end of the QRS complex and the beginning of the ST segment
absolute refractory (2)
-nothing can cause depolarization
-begins with P wave and goes halfway through T wave
relative refractory (2)
-will respond to strong stimulus (causing depolarization)
-begins second half of T wave and goes until next P wave
vulnerable period (3)
-extreme irritability
-top of T wave
-(first park of relative refractory) can result in V. tachy and V fib (lethal)
normal sinus rhythm
atrial rate-
PR interval -
QRS complex -
QT interval-
-atrial rate is 60-100
-.12-.20
-less then .12
-between .36 and .44 sec
*ventricular rate is the same as atrial rate
ST segment (2)
-changes will appear immediately after myocardial infarction, but they return to normal in 1-4 weeks
-T waves become symmetrical inverted 6-24 hours after infarction and return to normal anywhere from 2 weeks to several years later
Sinus bradycardia
characteristics (2)
clinical manifestations (2)
management (1)
-atrial and ventricular rates are equal and less than 60
-same sinus rhythm

-none unless pulse is very slow
-dizziness, syncope, hypotension, fatigue

-if pt is symptomatic, atropine or isoproterenol
sinus tachycardia
characteristics (2)
clinical manifestations (1)
management (2)
-atrial and ventricular rates are equal and greater than 100
-same sinus rhythm

-rapid pulse

-treating underlying cause
-digitalis or beta blockers
sinus arrhythmia
P wave:
atrial rhythm:
atrial rate:
PR interval:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave-always present
atrial rhythm-irregular, P-P variable
atrial rate-WNL
PR interval-varies slightly but WNL
QRS-WNL
QT-WNL
clin. man. -irregular pulse
manag.-none needed
Paroxysmal atrial tachycardia
P wave:
atrial rhythm:
atrial rate:
PR interval:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave-may have abnormal contour
atrial rhythm-regular
atrial rate-very rapid (150-250)
PR interval-WNL
QRS complex-may be narrowed
QT interval: difficult to measure because end of T wave is not clear
other: frequently occurs in healthy people, sometimes begins during sleep

clin. man: palpations, lighthead, if continues -> hypotension, CHF, shock
manag-valsalve maneuver, carotid massage, provide rest, meds to sedate pt, meds to slow electrical conduction (digitalis, verapamil, adenosine, Ca channel blockers, beta blockers
atrial flutter
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: saw tooth flutter
atrial rhythm: reg.
atrial rate: rapid, 250-400
PR interval: cant be measured
ventricular rhythm: reg or irreg, dependent on the ratio of flutter waves to QRS complexes
ventricular rate: ratio of flutter waves to QRS complexes from 2:1 to 6:1
QRS complex duration: WNL
QT internal: cant be measured

clinical manifestations: asymptomatic if the ventricular rate is WNL. s&s of decreased CO and BO. if its rapid -> palpations, dyspnea, angina, CHF. may need to call rapid response team.

management: admin meds to slow ventricular rate (Ca channel blockers, beta blockers), if rapid -> valsalve or carotid massage, synchronized cardioverson
-pt is at increased risk for developing clots in atria, on antithrombotic therapy. rate control is accomplished with meds that block the AV node. Elective cardioverion (on coumadin at least 6 weeks), or ablation in the EP lab
Atrial fibrillation
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: upright P wave NOT present
atrial rhythm: cant be measured
atrial rate: cant be measured, may be high (400 or more)
PR interval: none
ventricular rhythm: grossly irregular
ventricular rate: usually rapid, sporadic, unpredictable
QRS complex duration: WNL
QT internal: cant be measured
*** R to R will always be irregular
- common in old people

cause: ischemia heart disease, valvular heart disease, hyperthyroidism, lung disease, heart failure, aging
clinical manifestations: irregular pulse, apical-radial pulse deficit. if rapid -> palpations, angina, CHF
management: slow rapid ventricular pulse with Ca channel blockers or beta blockers, administer synchronized cardioversion, admin amiodarone followed by infusion or convert rhythm, anticoagulation therapy, vagal stimulation
First degree heart block
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: present, normal. everyone QRS has P
atrial rhythm: WNL
atrial rate: WNL
PR interval: prolonged, constant; >.20
ventricular rhythm: regular
ventricular rate:WNL
QRS complex duration: WNL
QT internal: WNL

clinical manifestations: none
management: none unless rate is slow
Second degree AV block (wenchebach/ mobitz I)
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: normal, not every P wave followed by QRS
atrial rhythm: reg
atrial rate: WNL
PR interval: becomes progressively longer until a P wave not followed by a QRS appears
ventricular rhythm: irregular
ventricular rate: less than atrial rate
QRS complex duration: WNL or slightly wider
QT internal: WNL

clinical manifestations: irregular pulse, may be slow
management: hold digitalis, careful monitoring because of potential to develop further degree of AV block, especially in the presents of AMI
second degree AV block (mobitz II)
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: normal, may be difficult to identify
atrial rhythm: regular
atrial rate: WNL
PR interval: constant, may be prolonged
ventricular rhythm: regularly irregular
ventricular rate: less than the atrial rate
QRS complex duration: varies dependent on the location of the block. if the QRS complex is narrow, the block is located high in the AV junction; if the complex is wide; the block is located father down the conduction system
QT internal: WNL

clinical manifestations: regular or irregular pulse, may be slow dependent on the degree of AB block
management: hold digitalis, give atropine IV push, obtain a 12-lead ECG, monitor for further conduction disturbances
three degree AV block (complete heart block)
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: present, no relationship between P waves and QRS complexes
atrial rhythm: mostly regular
atrial rate: greater than ventricular rate
PR interval: varies with every beat
ventricular rhythm: regular or irregular
ventricular rate: less than atrial ratel depends on location. intrinsic rate of AV junction is 40-60 beats/mini intrinsic rate of the ventriales is 20-40 beats/min
QRS complex duration: varies depends on locations
QT internal: WNL

clinical manifestations: slow pulse rate, patient may be symptomatic, dizzy, syncope, angina, CHF, hypotension
management: temp pacemaker insertion, atropine only affects the atrial rate
pacing rhythm
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: none may be present
atrial rhythm: cannot identify
atrial rate: cant be measured
PR interval: cant be measured
ventricular rhythm: regular
ventricular rate: dependent on the rate of the pacemaker
QRS complex duration: wider than normal, initiated by a "spike"
QT internal: may be WNL

clinical manifestations: none with normal functioning
management: none
premature ventricular contractions
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: not usually visible
atrial rhythm: regular
atrial rate: less than the ventricular rate
PR interval: WNL in normal sinus beats
ventricular rhythm: irregular
ventricular rate: greater than the atrial rate
QRS complex duration: wider than normal
QT internal: WNL

other: QRS complexes appear wide and bizarre; deflection is usually opposite that of the sinus beat; compensatory pause may follow PVC
clinical manifestations: palpation, "flip-flop", usually not palpable radially, early apical impulse, split s1 and s2
management: bolus IV amiodarone followed by IV infusion, bolus of IV libocaine followed by IV infusion is >6min, correct hypokalemia, correct hypoxia, give atropine sulfate IVP if HR is slow
ventricular tachycardia
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: not recognizable, obscured by QRS
atrial rhythm: cannot identify
atrial rate: cannot measure
PR interval: cannot measure
ventricular rhythm: reg
ventricular rate: usually rapid, 150-250
QRS complex duration: wide and symmetrical
QT internal: cannot be measured

clinical manifestations: usually no palpable pulses, if sustained, hemodynamic collapse, loss of consciousness, pulseless, apneic
management: precordial thump if rate >150, and rhythm is monitored and witnessed, IV bolus of lidocaine HCl or amiodarone followed by infusion. may administer meds phenytoin, synchronized cardioversion
ventricular fibrillation
P wave:
atrial rhythm:
atrial rate:
PR interval:
ventricular rhythm:
ventricular rate:
QRS complex duration:
QT internal:
clinical manifestations:
management:
P wave: no recognizable P waves
atrial rhythm: none
atrial rate: none
PR interval: none
ventricular rhythm: none
ventricular rate: none
QRS complex duration: not recognizable
QT internal: none, no recognizable T wave

clinical manifestations: pt is unconscious, no peripheral pulses, apneic
management: defibrillate immediately if cardiac arrest is witnessed, initiate CPR and continue until defibrillation is provided
premature atrial contraction (4)
-normal sinus with one PAC
-rate: matches that of the underlying rhythm
-the P wave of the PAC, normally looks different then the others
-PAC may cause palpitation
causes and care for premature atrial contraction
causes: stimulants (caffeine or tobacco), myocardial hypertrophy or dilatation, myocardia ischemia, lung disease, hypokalemia (4), hypomagnesemia (2)
treat: no treatment is indicated, may proceed atrial fib
nonconducted PAC
rhythm:
rate:
P wave:
PR interval:
QRS complex:
rhythm: underlying rhythm usually regular, irregular with non conducted PAC
rate: that of underlying rhythm
P wave: associated with the non-conducted PAC is premature, and abnormal in size, shape, or direction; often hidden in preceding T wave
PR interval: absent with non-conducted PAC
QRS complex: absent with nonconducted PAC
atrial tachycardia
rhythm:
rate:
P wave:
PR interval:
QRS complex:
rhythm: regular
rate: between 150-280 bpm
P wave: hidden or on the down slope of the previous T wave
PR interval: not measurable
QRS complex: .04-.1
Superventricular tachycardia (SVT)
(2)
causes:
treatment:
-the faster the rate the more symptoms
-arises from decreased CO and resultant decreased organ perfusion
causes: digitalis toxicity, electrolyte imbalance, lung disease, ischemic heart disease and cardiac valvular abnormalities
treatment: administer oxygen, antidysrthymic drugs (diltiazem, adenosine, beta blockers an amiodrone), vagel situations (bearing down, carotid message, face in ice water, gag reflex, squatting or breath holding), cadioversion ( synchronized shock may need to do emergently (give enough meds (ativan) so they dont remember)
cardioversion
delivers charge to R wave. make sure that this isnt done in vulnerable state (top of T wave)
Sinus tachycardia:
sinus bradycardia:
sinus arrhythmia :
-100-150
-40-60
-60-100
arrhythmia or dysrhythmia:
sinus arrhythmias:
-all rhythms other than the normal rhythms or the heart (normal sinus rhythm)

-disturbances in impulse discharge or impulse conduction from the sinus node
ST elevation:
ST elevation and T wave inversion:
ST depression:
injury
injury and ischemia
ischemia
causes of sinus tachycardia (7)
sympathetic stimulation: (3)
-hyperthyroidism, anemia, fever, hypovolemia, heart failure, exercise use of stimulants
-fear, pain, anxiety

*dysrthymia itself isnt treated, treat underlying cause
cause of sinus bradycardia (10)
treatment: (2)
-vasovagal response, meds (digoxin), calcium channel blockers, beta blockers, MI, normal physiological variant in athlete, diseases of the sinus node (SSS), increased ICP, hypoxemia, hypothermia
-assess for hemodynamic instability, if pt symptomatic (atropine (avoided if pt is hypothermic), transcutaneous pacing, dopamine, epinephrine
sinus arrhythmia (7)
patient response:
care and TX:
-a cyclical change in HR that is associated with respiration
-increased HR with inspiration
-decreased HR with expiration
-HR WNL (60-100)
-rhythm is cyclically irregular
-PR and QRS are WNL
-shape and sequence: Pwave before every QRS

-rhythm tolerated well. no treatment required
-this is a normal rhythm, common in kids
heart block
arrhythmias with delayed conduction or failed conduction of impulses through the AV node into the ventricles
-PR interval measure of conduction between initial stimulation of the atria and the initial stimulation of the ventricles
site of AV blocks
AV node:
Bundle of his:
bundle of branches:
-QRS complex normal (.10 second or less)

-QRS complex normal (.10 second or less)

-Bundle branches (QRS complete wise (greater than .10 sec))
classification of AV blocks
PR interbal determines type of block, QRS complex width determines location

first degree block
second degree block (type 1-mobitz I or wencheback)(type 2-mobitz II)
three degree block (complete heart block)
Mobitz I
-group of beats separated by a pause

cause: increased parasympathetic (vagal) tone, effects of meds (beta blockers, digitals, calcium channel blockers), hyerkalemia, normal in athletes
symptoms: usually temporary and resolved on its own, normally doesnt lead to higher degree block, normally asymptotic, if ventricular rate is slow ((symptomatic bradycardia: atropine, external or transvenous pacing, dopamine or epinephrine))
Mobitz II
more than one P wave before each QRS (2:1, 3:1)
-p waves are identical and appear regularly
-location of conduction disturbance is below the AV node in the bundle of his or bundle branches
-common after anterior wall MI
Mobitz II
causes:
symptoms:
treatment:
-acute myocarditis, degeneration of electrical conduction system

-if ventricular rate is slow decreased cardiac output (increased BP, SOB, heart failure, check pain, syncope)

-treatment is needed immediately for symptomatic mobitz II or if asymptomatic with wide QRS complexes (acute anterior wall MI)
-external pacemaker, dopamine infusion (increased blood pressure), permanent pacemaker
third degree AV block
"complete heart block"
-complete absence of conduction between the atria and the ventricles
-atria rate is controlled by sinus node (60-100 bpm)
-ventricular rate controlled by AV node (40-60), or in the ventricles (30-40)
characteristics of third degree AV block
associated with inferior-wall MI: (4)
associated with anterior wall MI (4)
result of block at level of the AB bundle of His
-rhythm usually stable, ventricles paced by junctional pacemaker
-narrow QRS complexes, ventricular rate 40-60
-resolved on its own

result of block within bundle branches
-rhythm usually unstable, ventricles paced by ventricular pacemaker
-wider QRS complexes, ventricular rate 40 bpm or less
-does not resolve on own, many require permeant pacemaker
Third degree AV block
causes:
symptoms:
treatment:
-older patients with degenerative changes in conduction system, lyme disease, digitalis toxicity

-if normal ventricular rate patient is relatively asymptotic (weakness, fatigue, dizziness, or exercise intolerance)
-extremely slow ventricular rate, decreased CO (hypotension, dyspnea, heart failure, check pain, strokes adams syncope)

-COMPLETE heart block ( serious, potentially life threatening)
-external pacemaker, temporary transvenous pacemaker, atropine (narrow QRS), hypotension (vasppressors- dopamine, levopred (sp?))
unresolved complete heart block- permaneent pacemaker
Tips to distinguish heart blocks
Measure P-P interval :
measure R-R interval:
measure PR interval:
Measure P-P interval
-P-P interval is reg in all blocks

measure R-R interval
-first degree and third degree AV blocks (regular ventricular rhythm)
-mobitz I (irregular ventricular rhythm )
-mobitz II (regular or irrgular ventricular rhythm)

measure PR internal:
-PR interval consistent (could be first degree or mobitz II)(mobitz II, two or more P waves to each QRS)
-PR interval is not constant (mobitz I, PR interval not constant, irregular ventricular rhythm)(third degree AV block, PR interval is not constant, regular ventricular rhythm)
again... her NOTES
first degree AV
-prolonged PR - but constant (>.2)
-every P will have QRS
-find underlying rhythm

Mobitz I
-PR will gradually lengthen
-will have P's with no QRS

Mobitz II
-PR will be constant (constantly with in norm limits or constantly long)
-will be P's without QRS's

complete heart block:
-QRS:reg, R-R: reg, P-reg
-will have P without QRS
-P's have NO relationship to QRS
Students also viewed