ECG Basics

Torsades de Pointes: Form of V-Tach

"Twisting of the points". Rhythm: regular or irregular Rate: >200 P waves: none PR Interval: none QRS Interval: Wide, bizarre >0.12 second ST Segment: none T wave: opposite the QRS but may not be seen due to rapid rate

Prolonged PR Interval

* Prolonged P wave = conduction problem (1st degree block) A prolonged PR Interval(greater than 0.20 sec) may mean that the electrical impulse is delayed as it travels through the AV node and bundle of His. Short PR(Less than 0.12 sec) Interval can mean that the impulse originated somewhere other than the SA node.

QRS Complex

* Represents depolarization of the ventricles (contraction) * Follows th PR interval * < 0.12 sec (2-3 lil boxes) * Q wave 0.04 sec or wider or 1/4 size of R wave indicates MI * greater than 0.12 = bundle branch block * Repolarization of Atria hidden

ST Segment

* Represents the ventricular cell in refractory period (resting) * Should be isoelectric * elevated or raised ST segment = Acute MI * depressed ST segment = Digoxin dip (toxic) or MI Represents early ventricular repolarization. Usually isoelectric. Elevation or depression of the ST segment 1 mm or more above or below the baseline is considered abnormal.

PR Interval

* electrical impulse to leave SA node and travel thru Atria to AV node, bundle branches and purkinje network. * Starts at P wave to the beginning of QRS complex. * 0.12 to 0.20 sec(3-5 lil boxes) Remember, 5 lil squares = 0.20 sec

P Wave

*Represents atrial depolarization *< 0.10 sec *Abnormal P waves indicates altered or damaged atria or impulse originated outside the SA node

U Wave

*Represents repolarization of the purkinje fibers * Rarely seen *Follows T Wave and comes before the next P wave * Same deflection as the Pwave but smaller * Taller than 2 mm = hypokalemia or toxic digoxin or quinidine The U Wave is a wave not well understood. Know that it is not easily identified nor necessary to calculate. However, a U wave taller than 2 mm is considered abnormal and may suggest hypokalemia or the toxic effects of digoxin or quinidine.

T Wave

*Represents repolarization of the ventricles * Always follows the QRS *Usually defection is the same as QRS *Amplitude is < or = to 5 mm *Appearance is upright * Variations( Inverted= myocardial ischemia, Peaked/Tall= hyperkalemia)

Steps to read a Telemetry Step

1. Rhythm ( Regular or Irregular) Compare two R's should be within 0.04 sec 2. Rate (count # of R's per 6 sec strip X 10) 3. P waves (look alike?, occur reg rate?, P wave before each QRS?) 4. PR Interval ( consistant?) (0.12 to 0.20) 5. QRS Complex ( 0.12 or less?) 6. T Wave ( elevated, depressed, greater than 5mm?) 7. U wave ( present?, follow the T wave?)

A Fib Causes/Symptoms/Effects/TX

Cause MI Lung Disease Symptoms: Palpitations or chest discomfort Shortness of air and possibly respiratory distress Hypotension, light-headedness and possibly loss of consciousness Peripheral edema, jugular vein distention, and possibly pulmonary edema Effect Decreased cardiac output; increased risk for blood clots to lungs and brain Treatment: < 48 hrs Digoxin, Calcium Channel Blockers; Beta Blockers; Amiodarone Cardioversion Oxygen > 48 hrs Coumadin Heparin Therapy until Transesophageal Echocardiogram is performed to rule out clot in atrium Oxygen

Premature Atrial Causes/Effect/TX

Cause: Medications that are stimulants Caffeine Tobacco Hypoxia Heart Disease Occasional is normal Effect: No effects May be sign of impending heart failure or atrial tachycardia Treatment: Omit caffeine, tobacco and other stimulants Digoxin; Quinidine Oxygen Treat heart failure Effect: No effects May be sign of impending heart failure or atrial tachycardia

PAT Causes/Symptoms/Effects/TX

Cause: Medications that are stimulants Caffeine Tobacco Hypoxia Heart Disease Occasional is normal Symptoms: None or Palpations Bounding pulse Dizziness Fainting Shortness of breath Chest Pain Throat tightness Diaphoresis Effect: Prolonged runs can decrease cardiac output. Treatment: Digitalis, calcium channel blockers, beta blockers, sedation; amiodarone, adenosine, oxygen

1st Degree Block Causes/Effects/Tx

Cause: AV node ischemia, digitalis toxicity, side effect of other meds such as beta blockers or calcium channel blockers. Effects: None Treatment: Remove cause

V-Fib Cause/Effect/TX

Cause: Acute MI, untreated or unsuccessful treatment of V-Tach, cardiomyopathy, valvular heart disease, acid/base and electrolyte imbalances, electrical shock, overdose. Effect: Cardiac arrest (Death) Treatment: Immediate defibrillation (CPR until defib available). Medications: epinephrine, lidocaine, procainamide, amiodarone, oxygen.

PVCs Cause/Symptoms/Effects/TX

Cause: Heart disease; hypokalemia; hypoxia; low blood magnesium levels, stimulants, caffeine, stress, or anxiety. Symptoms: None Odd sensation in chest: feels like heart is flipping or having palpations Effects: Occasional occurrence-no effect Six or more per minute or PVCs very close to preceding T wave can progress to lethal arrhythmias like V-Tach or V-Fib. Multi-focal PVCs means multiple irritable areas in ventricles Treatment: Treat cause Oxygen Amiodarone Pronestyl Associated with bradycardia give atropine

3rd Degree Block Causes/Symptoms/Effects/TX

Cause: MI; conduction system lesion; medication side effects; hypoxia Symptoms: Chest pain Palpitations Shortness of breath Symptoms worse Diaphoresis on exertion Fatigue Faintness or fainting Pulse may be weak and thready Call CODE! Effect: Low cardiac output, patient may or may not be symptomatic Treatment: Temporary pacemaker then a permanent pacemaker; Atropine, epinephrine or dopamine can be given until pacemaker inserted. Oxygen Sometimes Dopamine is given for vasoconstriction to get a better BP

Asystole: Flat Line

Cause: Profound cardiac or other body system damage; profound hypoxia. Effect: death Treatment: Atropine, epinephrine, CPR, pacemaker, dopamine, oxygen Do defib there must be some kind of elecrical activity showing on the monitor. If you can at least get them into v-fib you can defib.

SVT Causes/Symptoms/Effects/TX

Cause: Same as PAT Symptoms: Shortness of air Palpitation feeling in chest Ongoing chest pain Dizziness Rapid breathing Loss of consciousness Numbness of body parts Effect: Decreased cardiac output secondary to the rapid heart rate Treatment: If stable: Digoxin, calcium channel blockers, beta blockers. Oxygen If unstable: cardioversion

V-Tach Cause/Symptoms/Effects/TX

Cause: Same as PVCs Symptoms : Congestive heart failure (CHF) Dyspnea and hypoxemia Rales from pulmonary edema Jugular venous distention Hypotension Mental status changes Anxiety Agitation Lethargy Coma Effect: Not tolerated well. Can cause shock, unconsciousness and death if untreated Treatment: Medications: Amiodarone, procainamide, lidocaine Cardioversion Treat cause CPR Immediate defibrillation ( pulseless V-Tach)

Atrial Flutter Causes/Symptoms/Effects/TX

Causes: Heart Disease, PE, Valvular Heart Disease; Thyrotoxicosis; Lung Disease Symptoms: palpitations, chest pain or discomfort shortness of air lightheadedness or dizziness nausea nervousness and feelings of impending doom symptoms of heart failure such as activity intolerance and swelling of the legs occur with prolonged fast flutter) Effects: Decreased cardiac output; increased oxygen requirements Treatment: Digoxin Calcium Channel Blockers Adenosine Carotid Sinus massage-slow vent. Rate Electrical Cardioversion

Sinus Tach Effects / TX

EFX: Decreased CO. Increased Cardiac Workload TX: Treat underlying cause, O2, Tylenol/ IBU (fever), if persistant Tach: Beta Blockers to slow Rate.

(PAT) Paraoxymal Atrial Tachycardia

Effect: No effects May be sign of impending heart failure or atrial tachycardia Treatment: Omit caffeine, tobacco and other stimulants Digoxin; Quinidine Oxygen Treat heart failure a sudden burst of three or more PACs in a row; usurps underlying rhythm

Atrial Fibrillation

Hundreds of impulses from different locations in atria are firing. As a result, atrial depolarization does not occur as a unit but in small sections. The atria wiggles. Rhythm: irregular Rate Atrial rate 350-700>not measured Ventricular rate Controlled - vent. rate is ≤ 100 Uncontrolled - vent rate is ≥ 101 P wave: None; Fibrillatory waves PR Interval: none QRS Interval: ≤0.12 ST Segment: isoelectric; elevated; depressed T Wave: upright; ≤ 5 mm ampli tude

(V-Fib) Ventricular Fibrilliation

Hundreds of impulses in the ventricles are firing, each depolarizing its own piece of territory. Ventricles wiggle instead of contract. Rhythm: very irregular, no pattern Rate: unable to count P waves: none PR Interval: none QRS Interval: none detected T wave: none Course onset more likely to be reversed Fine onset present for longer and may require drug therapy first then defib

ST Segment Variation (Elevated Segment)

Indicates Acute Myocardial Infarction (MI)

ST Segment Variation (Depressd ST Segment)

Indicates Myocardial Ischemia

P Wave (Wide)

Left Atrium Enlargement

Atrial Rhythm Criteria

Matching upright P's with atrial rate >160 No P's at all; wavy or sawtooth baseline between QRS present Premature abnormal P wave Heart rate ≥130, rhythm regular, P waves not discernible

Sinus Tach Causes / Symptoms

Meds: atropine Diseases: PE, MI, HF, Fever, Inhibition of vagus nerve, thyrotoxicosis Hypoxia Symptoms: Palpitations, Dizzy, periodic chest pain-sometimes sharp, fatigue, SOB, Activity Intolerance

Another "Normal" QRS

Not all complex have all three waves. This slide shows some common variations.

Atrial Rhythms

Originate in one or more irritable foci in the atria Called an ectopic rhythm when pacemaker site is outside of the SA node Sites in the atrium usurp the SA Node as the pacemaker These rhythms tend to be very fast and patients are often symptomatic Overall treatment is conversion Atrial rhythms have multiple and variable criteria Treatment goal is to convert rhythm back to sinus rhythm or return heart rate to more normal rates.

Sinus Rythm

Originates: SA node Rhythm: regular Rate: Fast or slow < or = to 160 bpm at rest Must have all three criteria * Upright P waves followed by a QRS *PR Intervals: constant 0.12 to 0.20 * Rate < or = to 160 bpm at rest ( Higher = SVT) Only TX if symptomatic

Telemetry Strip

P wave represents atrial depolarization QRS represents ventricular depolarization T wave represents ventricular repolarization Atrial repolarization? Occurring at the same time as ventricular depolarization, therefore not seen on ECG.

(PVCs) Premature Ventricular Complexes

Premature beats originating in an irritable ventricular tissue before the next sinus beat Rhythm: depends on underlying rhythm Rate: can occur at any rate P waves: not seen with PVCs PR Interval: none QRS Interval: Wide and bizarre in shape >0.12 seconds ST Segment: underlying rhythm: isoelectric; elevated; depressed. None in premature beat T Wave: slopes off in opposite direction to QRS. If QRS upward then t wave will pint downward

Atrial Flutter

Results when one irritable atrial foci fires out regular impulses at a rap id rate. This results in a flutter pattern. The AV Node is bombarded with so many impulses it lets some through but blocks others. Rhythm Regular if impulses from one foci Irregular if from various foci Rate Atrial rate 250-350 Ventricular rate: depends on conduction rate P waves No P waves; flutter waves with saw tooth appearance PR Interval Not measured QRS Interval: ≤0.12 ST Segment:: isoelectric, above, or below line T wave: upright, ≤ 5 mm amplitude

Ventricular Rhythms

Rhythm originate in the ventricular tissue Impulse is conducted slowly through the ventricle producing a wide QRS complex that measure >0.12 seconds. Impulse can travel backward to depolarize the atria resulting in the P wave lost in the QRS complex. Conduction systems last attempt at a pacemaker. Potentially most lethal of all rhythms Treatment goal is to restore sinus rhythm Criteria: Wide QRS > 0.12 seconds without preceding P wave No QRS at all Premature, wide QRS beat without preceding P wave, interrupting another rhythm

Sinus Bradycardia

Rhythm: Regular Rate: , or = to 59 bpm P Wave: 1:1 normal appearance PR Interval: 0.12 to 0.20 sec QRS Interval: < or = to 0.12 sec ST Segment: isoelectric T Wave: upright, < or = to 5mm amplitude Only difference between Normal Sinus and Sinus Brady is slow Rate. Normal for Athletes Causes: *Vagal Stimulation ie, vommiting, valsalva maneuver *Meds: Could be related to CC Blockers or B Blockers or Dig Toxicity, *MI,*Hypoxia Effects: Decreased CO TX: None unless symptomatic Symptomatic: Atropine, dopamine (infusion), and epinephrine, O2, Pacemaker

Sinus Tachycardia

Rhythm: Regular Rate: 101-160 bpm P wave 1:1 normal appearance PR Interval: 0.12 - 0.20 sec QRS Interval: < or = to 0.12 sec ST Segment: Isoelectric TWave: upright < or= to 5mm

Normal Sinus Rythym

Rhythm: Regular Rate: 60-100 bpm P Wave: 1:1 normal appearance PR Interval: 0.12 - 0.20 QRS Interval: < or = to 0.12 sec ST Segment: isoelectric T Wave: upright: < or = to 5 mm

Premature Atrial Complexes

Rhythm: Regular until premature beat Rate: Can occur at any rate P Wave: shaped differently; if preceding T wave looks different than the rest of the T waves the P is buried in the T deforming the wave PR Interval: if present 0.12-0.20 sec QRS Interval: ≤0.12 sec ST Segment: isoelectric; elevated; depressed T Wave: upright; ≤ 5 mm amplitude beats that are fired from an irritable foci in the atria before the next sinus beat is due

P Wave (Tall)

Right Atrium Enlargement

ST Segment Variation (Digoxin Dip)

ST Segment Digoxin Dip

AV Blocks

Sinus node fires as usual, there is a partial or complete interruption in the transmission of these impulses to the ventricles. Site of block is either the AV node or at the bundle branches. The underlying rhythm is sinus. Heart rates can be normal or very slow and patient may be symptomatic or non symptomatic Treatment goal is to increase heart rate and improve AV conduction. Criteria: PR interval prolonged >0.20 Some Ps not followed by a QRS; P-P interval regular

3rd Degree Block

The sinus node sends out impulses as usual but they are not transmitted to the ventricles because of a complete block in the AV node or the bundle branches Rhythm: Regular Rate: Atrial rate: 60-10 CO drops tremendously Vent. Rate: 20-30 P waves: normal sinus Ps. Can march P all the way across the strip. No association with QRS. PR Interval: None QRS Interval: ≤0.12 or ≥0.12 ST Segment: isoelectric; elevated; depressed T Wave: upright; ≤ 5 mm amplitude

1st Degree Block

There is a delay in the AV nodes conduction of sinus impulses to the ventricles. Rhythm: depends on underlying rhythm Rate: any rate P waves: upright; 1:1 PR Interval: Prolonged, ≥0.21 QRS Interval: ≤0.12 ST Segment: isoelectric; elevated; depressed T Wave: upright; ≤ 5 mm amplitude

Torsades de Pointes Cause/Symptoms/Effects/TX

This rhythm means the ventricles are very irritable and it must be treated immediately or V-fib will occur Cause: Antiarrhythmic medication such as procainamide; amiodarone Hypokalemia and/ or Hypomagnesemia levels Symptoms: Tachycardia Hypotension or Normotension Transient or prolonged loss of consciousness Palpations Pallor Diaphoresis Effect: Cardiac arrest Treatment: IV magnesium Cardioversion Isuprel Oxygen

(V-Tach)Ventricular Tachycardia

V-tach is defined as three or more PVC's in a row, occurring at a rate >100.V-tach can present with a pulse or without a pulse. Always assess your patient for a pulse when you see this rhythm. V-tach will be treated depending on the severity or pt. tolerance. An irritable focus in the ventricle has usurped the sinus node to become the pacemaker and is firing rapidly. Rhythm: regular or irregular Rate: >100 P waves: none PR Interval: none QRS Interval: Wide, bizarre, >0.12 ST segment: none T wave: slopes off in the opposite direction to the QRS

(SVT) Supraventricular Tachycardia

originates above the ventricles in either the SA node, the atrium, or the AV node. Rhythm: regular Rate: 130 and higher P waves: not identifiable PR Interval: none QRS Interval: ≤0.12 ST Segment: isoelectric; elevated; depressed T Wave: upright; ≤ 5 mm amplitude