KIN 569 EKG powerpoint

right axis deviation

100 to 180 degrees -1 and +aVF normal variant, RVH, MI of lateral wall, chronic lung disease, acute pulmonary embolism

AV junction intrinsic rate

40-60/min

sinus tachycardia

>100bpm regular rhythm PR interval 0.12-0.20 QRS <0.12 P wave before each QRS

lead III

LA (-) to LL (+), 120 degrees

left atrial hypertrophy

M shaped, widened P wave in one or more of leads I, II, aVL

pacemaker potential

SA and AV nodes have a "less negative" resting potential. SA node has a steeper slope for pacemaker potential than AV so it triggers that action potential that arrives at AV before it reaches its threshold

order of depolarization

SA node, atria, AV node, bundle of HIS, bundle branches, purkinje fibers, ventricles

infarction

ST segment elevation=hallmark of acute infarction T wave inversion Q waves are 25% of R wave

atrial fibrillation

multiple pacemaker sites atria and ventricles not coordinated similar causes as atrial flutter no distinct p waves baseline is junky

atrial flutter

no p waves ectopic focus for pacemaker causes include hypoxia and CHF saw tooth pattern can be regular or irregular

PR interval

from beginning of P wave to end of QRS complex

V2, V3, V4

anterior leads

PVC

area within ventricles that becomes irritated wide and abnormal QRS

third degree av block

atria and ventricles are depolarizing independently no association between atria and ventricles

P wave

atrial depolarization

left ventricular hypertrophy

deepest S in V1 or V2 and tallest R wave in V5 or V6 strain pattern (asymmetric ST segment depression and T wave inversion)

aVF

inferior lead (90 degrees) foot

aVL

lateral lead (30 degrees) left shoulder

V4, V5, V6

lateral leads

posterior myocardial infarction

lead V1

lateral myocardial infarction

leads I, aVL, V5, V6 occlusion of left circumflex coronary artery, marginal branch of left circumflex artery or diagonal branch of left anterior descending artery

inferior myocardial infarction

leads II, III, aVF, V6

QRS complex

looks different with different leads, ventricular depolarization, atrial repolarization is lost

right ventricular hypertrophy

low voltage tall R wave in V1 persistent precordial S waves "strain" in inferior (I, III, aVF) or anterior leads (V1-V3)

right atrial hypertrophy

prominent >2.5 mm tall, peaked P waves in leads II, III, and aVF

ventricular fibrillation

requires immediate CPR and defibrillation not able to maintain cardiac output HR 300-600 extremely irregular rhythm no p waves no PR interval

First degree Av block

rhythm is regular rate is of underlying rhythm PR interval is greater than 0.2 seconds QRS is usually normal

aVR

right shoulder

V1 and V2

septal leads

second degree av block type 1 (wenckeback)

successively longer PR intervals until a QRS fails rhythm is often irregular QRS is normal

axis

the average direction (orientation) of the hearts electrical activity current moving toward the positive electrode of a lead will result in a positive deflection current moving away results in a negative deflection

EKG

the graphic representation of the hearts electrical activity

T wave

ventricular repolarization

second degree av block type 2

2 to 1 or 3 to 1 pattern of p waves to QRS complex

ventricular intrinsic rate

20-40/min

ventricular tachycardia

3 Or More PVCs In A Row And A Heart Rate Of 150-250 BPM. Wide,bizarre QRS complexes with T Waves pointing in the opposite direction from the main QRS direction.

normal sinus rhythm

60-100 bpm regular rhythm PR interval 0.12-0.20 QRS <0.12 P wave before each QRS

sinus intrinsic pacemaker rate

60-100/min

sinus arrhythmia

60-100bpm irregular rhythm PR interval 0.12-0.20 QRS <0.12

sinus bradycardia

<60bpm regular rhythm PR interval 0.12-0.20 QRS interval <0.12 P wave before each QRS

left axis deviation

-30 to -90 degrees +1 and -aVF normal variant, LVH, LBBB

normal axis

-30 to 90/100 degrees +1 and +aVF

no mans land

-90 to 180 degrees

rate

1500/number of small boxes between successive waves paper speed at 25 mm/sec

anterior myocardial infarction

Leads 1, V2, V3, V4 occlusion of proximal left anterior descending coronary artery

right bundle branch block

QRS widening of at least 0.11 seconds 2 r waves in lead V1 wide terminal s in leads 1 and V6 "bunny ears" seen in leads close to the right side (V1 and V2)

Left bundle branch block

QRS widening of at least 0.12 seconds upright QRS complex in leads 1 and V6 predominately negative QRS complex in V1

lead I

RA (-) to LA (+), 0 degrees

lead II

RA (-) to LL (+), 60 degrees