12L EKG REFRESHER KALAH ERICKSON, BAN, RN STEMI NURSE NAVIGATOR SANFORD HEALTH - FARGO DISCLOSURES

• No financial disclosures

Personal Disclosure: I struggled with everything cardiac in Nursing School, so... if you struggle, that’s OK!

It will come with time and practice. LEARNING OBJECTIVES

• Describe the anatomy of a 12L EKG • Explain proper patch placement to obtain a 12L EKG • Identify infarct territory on a 12L EKG showing STEMI • List two significant EKG changes • List three STEMI mimics that are seen on a 12L EKG

QUESTION

How comfortable do you feel reading a 12L EKG?

A B C

WHAT IS A 12 LEAD EKG? Limb Leads Chest Leads • Representation of the heart’s electrical activity • 10 electrodes • Capturing flow of impulses

• 12 pictures • Pictures of electrical flow from different angles

We don’t need these rhythm strips for STEMI/NSTEMI identification ECG PAPER ANATOMY OF A 12 LEAD EKG

10 second rhythm strips QUESTION

How many mm is each small box on an EKG? a. 1 b. 0.1 c. 0.4 d. 0.5 e. 5 PATCH PLACEMENT

1st Intercostal Space

2nd Intercostal Space

3rd Intercostal Space 12 LEAD VIEWS

V1 & V2

THE 3 I’S – INJURY - INFARCT

• The Three I’s of ACS • Ischemia • What causes it? • Injury • Lack of oxygen to meet • Infarct myocardial cell demand Demand • Mismatch of supply and demand Supply

• Increased Demand • Decreased Supply • Gradual process • Abrupt event • Stressful activities • Thrombosis • Stress test in the clinic • Spasm ISCHEMIA – INJURY - INFARCT

• What will the EKG show?

• What else causes ST Depression? • ST Depression • Wandering baseline • • Hyperventilation inversion • Side effect of • Tall peaked T waves • • R or L • • • prolapse • Central nervous system disease • Reciprocal changes of ST elevation ISCHEMIA – INJURY - INFARCT

• The Three I’s of ACS • Lack of oxygen • Ischemia • Injury to myocardial cells • Injury • Alterations in depolarization and • Infarct repolarization • May affect to epicardium • ST Elevation • Presume AMI/heart attack STEMI CRITERIA

• ST Elevation inThe 2 contiguous easy way….. leads • 2mm in V2-V3 for men • 1.5mm in V2≥1mm-V3 forof ST women elevation • 1mm in all otherIn 2 contiguous leads leads ISCHEMIA – INJURY - INFARCT

• The Three I’s of ACS • Ischemia • Death of tissue • Injury • Q waves • Infarct

LOCATING INFARCT TERRITORY INFARCT TERRITORY INFERIOR WALL

• II, III and aVF • View from left leg • Inferior wall of LV • Elevation = RCA occlusion • Watch for ST Depression or flipped T waves in aVL • Inferior MI

II, III and AVF INFERIOR MI RCA – RIGHT CORONARY ARTERY

• Supplies • Right atrium • Right ventricle • 25-35% of the LV • SA node in 60% of the population • EKG Changes • • Hypotension • • Heart blocks • Symptoms • Nausea and vomiting • RCA blockages account for 60% of all STEMI’s

SEPTAL AND ANTERIOR WALLS

• V1 and V2 • Septal Wall • V3 and V4 • Anterior Wall • Elevation = LAD occlusion V1 & V2 ANTERIOR MI LAD – LEFT ANTERIOR DESCENDING

• Supplies • Anterolateral (front and side) LV • Apex • Interventricular septum • 45-55% of the LV • LAD Blockage is particularly associated with mortality • Provides much of the blood flow for the LV • Systemic circulation • EKG Changes • Bundle branch blocks • 2nd Degree Type 2 • Complete LATERAL WALL • I, aVL, V5, V6 • Side view of the heart • Often occurs in combination with an inferior or anterior infarction • Lateral wall of the LV is supplied by branches off of the LAD and Circ • Culprit artery depends on where your elevation is at CIRCUMFLEX

• Supplies • Left atrium • Posterolateral (back and side) LV • Anterolateral papillary muscle • SA node in 38% of population POSTERIOR WALL • Known as the “dark side of the moon” • No leads look directly at this area • Viewed as a mirror image of anterior infarct • Deep ST depression in V1-V3 V1 & V2 • Occur with inferior or lateral MI

V3 POSTERIOR EKG You will likely receive an order from your Physician to obtain this type of EKG

At least 0.5mm of ST elevation in one lead indicates posterior STEMI

SIGNIFICANT EKG CHANGES LEFT MAIN DISEASE • Known as the “Widow Maker” • Widespread horizontal ST depression • ST elevation (≥1mm) in aVR • May indicate a blockage in the proximal LAD or Left Main Blow back of contrast LEFT MAIN DISEASE dye due to tight blockage Angiogram Catheter

LAD

Circ Why are these EKG changes something you should tell someone about?!

Sternal wires from previous CABG LEFT

• Activation of the LV is delayed • Depolarization starts and gets hung up at the L bundle • What will you see? • V1 • Wide QRS • Negative QRS • V6 • Wide QRS • Positive QRS • Inverted T wave

• LBBB severely distorts the QRS complex • Unreliable interpretation of ST segment • What’s most important? • Is this a new LBBB? • Look for a previous EKG • Ask the patient • Acute MI’s presenting as a new LBBB have the highest mortality rate • If related to ischemia, a LBBB occurs due to a large amount of anterior ischemia LEFT BUNDLE BRANCH BLOCK EKG CAUSES OF A LEFT BUNDLE

• • Dilated • Acute • Extensive • Primary disease of the cardiac electrical conduction system • Long standing HTN leading to aortic root dilatation and aortic regurgitation • Lyme disease

STEMI MIMICS TAKOTSUBO

• Non- • Sudden temporary weakness of the LV • Normal coronary arteries on angiogram • Triggered by emotional stress (AKA Broken Heart Syndrome) • Break up • Death of a loved one • Constant anxiety Occurs almost Treatment: HF Meds • EKG Characteristics • Beta Blockers exclusively in • Anterior ST elevation • Ace Inhibitors women • Diuretics TAKOTSUBO PRINZMETAL’S

• Caused by vasospasm • Contraction of the smooth muscle tissue in the vessel walls • Can be caused by: • Exposure to cold weather Pain or Discomfort: • Stress • At rest, midnight-early am • Medications • Usually severe • Relieved by medications • Smoking • Cocaine use

• Causes ST elevation with reciprocal changes during episodes of chest pain • EKG changes are normally transient and reversible with vasodilators EARLY REPOLARIZATION

• Mild ST elevation (concave) • Tall T waves (precordial leads) • Common in: • Young/healthy males • Athletes • Notching of the J-point • Fish hook pattern • No reciprocal changes EARLY REPOLARIZATION LEFT VENTRICULAR HYPERTROPHY

• Thickening of the myocardium of the LV • What will you see? • Tall peaked R waves • Concave ST elevation • Deep S waves with ST elevation in V1-V3 • ST depression and T wave inversion in V5-V6 • What causes it? • Aortic stenosis • Mitral insufficiency • HTN • Hypertrophic LEFT VENTRICULAR HYPERTROPHY

• Inflammation of the • What will you see? • Diffuse ST elevation • PR segment depression • Especially in lead II • ST elevation often times maximal in II, V5 and V6 • ST depression and PR elevation in aVR • No reciprocal changes PERICARDITIS

ANY QUESTIONS?

KALAH ERICKSON, BAN, RN STEMI NURSE NAVIGATOR [email protected]