Category: Cardiovascular

Complications of Myocardial Infarction

Mnemonic: DARTH VADER

Death

Arrhythmia

  • ACS patients need to be placed on cardiac monitor
  • Frequently degenerate into non-perfusing rhythms

Rupture of Ventricle

  • Occur within a few days of myocardial infarction
  • Rapid decompensation
  • Bedside ultrasound will show pericardial effusion and tamponade

Tamponade

  • Multiple etiologies
    • Rupture of ventricle (see above)
    • Pericarditis
  • Becks Triad
    • Jugular vein distension
    • Muffled heart sounds
    • Hypotension
  • Diagnosed with bedside ultrasound
  • Treatment is pericardiocentesis

Heart Failure

  • Occurs in approximately 1/3 post-MI patients
  • Leads to cardiogenic shock
  • Treatment
    • Fluid bolus
    • Vasopressors (esp. norepinephrine)
    • Inotropes (milrinone, dobutimine)
    • Left ventricular assist devices
    • Intra-aortic balloon pumps

Valve Failure/Rupture

  • Rapid decompensation (similar to ventricular wall rupture)
  • PLUS
  • New heart murmur
  • Surgical emergency

Aneurysm

  • A classic STEMI mimic
  • Large Q waves with ST segment elevation (IN ASYMPTOMATIC PATIENT)

Dresslers Syndrome/Pericarditis

  • Rule out cardiac tamponade
  • Treatment
    • NSAIDS/colchicine

Embolism

  • Occur in damaged ventricles and in cardiac aneurysms
  • Require anticoagulation

Recurrence

  • Emphasize lifestyle management

Additional Reading

How to Read an EKG

Always remember…1, 2, 3, get an old EKG!!!

Step 1: Identify the Rate and Rhythm

  • Is it sinus rhythm?
    • P wave before every QRS
  • Is it one of the tachycardias? (Refer to THIS episode)
  • Is it one of the bradycardias? (Refer to THIS episode)

Step 2: Look for Signs of Ischemia

  • Most consistent way is to examine by anatomic region of the heart
    • II, III, and aVF are “inferior” leads
    • I, aVL, V5, V6 are “lateral” leads
    • V1 and V2 are “septal” leads
    • V3 and V4 are “anterior” leads
  • Check for Q waves
  • Check for ST segment elevation or depression
    • Compare the J point with baseline (TP segment)
  • Check for peaked T waves and T wave inversions
    • T wave inversions in V1 and aVR are normal

Step 3: Look at Intervals

  • PR interval
    • Wolf-Parkinson White Syndrome
    • 1st degree heart block
  • QRS interval
    • Left bundle branch block
    • Right bundle branch block
    • Sodium channel blockade
  • QT interval
    • Long QT syndrome
    • Hypokalemia
    • Risk of torsades de pointes

Step 4: Get an Old EKG

  • If you find anything abnormal looking, compare to an old EKG

Bonus: Scarbossa Criteria

  • Identifies ischemia in patients with a left bundle branch block
    • 1 lead with concordant ST elevation
    • 1 lead with concordant ST depression (V1-V3)
    • Severely discordant ST elevation (>25% preceding S wave)

Additional Reading

Bradycardia

Differential Diagnosis

  • Mnemonic: HE DIES
    • Hypothyroidism
    • Elevated intracranial pressure (ICP)
      • Cushings reflex
        • Bradycardia
        • Increased blood pressure
        • Irregular breathing
    • Drugs
      • Beta blockers
      • Calcium channel blockers
      • Digoxin
    • Ischemia
    • Electrolytes
      • Especially potassium!!!
    • Sick Sinus Syndrome

Approach to Bradycardia

  • Step 1: Get an EKG
    • Ischemia?
    • Heart block?
      • 1st degree = PR interval >200ms (5 small boxes)
      • 2nd degree type 1 = PR gradually prolongs until dropped beat
      • 2nd degree type 2 = Intermittent dropped beats
      • 3rd degree = None of the atrial beats result in a ventricular beat
    • Evidence of hyperkalemia?
  • Step 2: Determine if patient is SYMPTOMATIC
    • Hypotension
    • Chest Pain
    • Syncope
    • Lightheadedness
    • Note: Many patients have benign and asymptomatic resting bradycardia (I’ve seen as low as 30s!) and this does not necessarily require aggressive treatments/IV medications
  • Step 3: If patient is having symptoms… Give atropine!
    • Typical dose is 0.5mg IV atropine
  • Step 4: If patient still having symptoms… Give epinephrine!
  • Step 5: If patient still having symptoms… Cardiac pacing!
    • If symptoms are minimal or resolved, patient can sometimes wait for permanent pacemaker with cardiology
    • Transcutaneous pacing
      • Sometimes difficult to get mechanical capture
    • Transvenous pacing
      • Place through the right internal jugular vein

Additional Reading

Tachycardia

Basic Approach

  • Step 1: Is this SINUS tachycardia?
    • P before every QRS?
    • Treat the underlying condition
  • Step 2: Is this a NARROW and REGULAR rhythm?
    • SVT
      • Treat with vagal maneuvers or adenosine
      • Another new trend is treating with calcium channel blockers!!
    • ORTHOdromic Wolf Parkinson White
      • Treat with adenosine
    • Atrial flutter with fixed block
      • Treat with AV blockers (diltiazem)
        • Slows the heart rate
  • Step 3: Is this a NARROW and IRREGULAR tachycardia?
    • Almost always atrial fibrillation
      • Treat with AV blockers (diltiazem)
    • Other (less common) diagnoses
      • Atrial flutter with variable block
      • Multifocal atrial tachycardia
  • Step 4: Is this a WIDE and REGULAR tachycardia?
    • Assume ventricular tachycardia until proven otherwise
      • Treatment is immediate cardioversion if unstable
      • May try chemical cardioversion if stable
        • Procainamide
        • Amiodarone
        • Lidocaine
    • Other diagnoses
      • ANTIdromic Wolf Parkinson White
      • Narrow complex tachycardias PLUS aberrancy
  • Step 5: Is this a WIDE and IRREGULAR tachycardia?
    • Atrial fibrillation with bundle branch block
      • Extremely fast and bizarre in appearance?
        • Consider atrial fibrillation with Wolf Parkinson White

Additional Reading

  • Calcium Channel Blockers for Stable SVT (ALiEM)
  • Atrial Fibrillation in WPW – Pearls and Pitfalls (County EM)

Syncope

6 EKG Findings. 6 Risk Factors. 6 Mimics.

Step 1: Get an EKG

  • This is the only “required” test for a patient with syncope
  • Other common tests
    • CBC
      • Evaluate for anemia
    • hCG
      • If patient might be pregnant

Step 2: Look For 6 High Risk EKG Patterns

  • Mnemonic: QT-BRIDE
    • QT prolongation
      • Especially QTc >500
    • Brugada pattern
    • Right heart strain
      • Tachycardia
      • S1Q3T3
      • Inverted T waves precordial leads
    • Ischemic changes
      • ST segment elevation/depression
      • T wave inversion
    • Delta waves
      • Seen in Wolf-Parkinson White (WPW)
    • Epsilon waves
      • Seen in arrhythmogenic right ventricular dysplasia (ARVD)

Step 3: Ask the 6 High Risk Historical Questions

  • Mnemonic: CHESS +1
    • Cardiac history
      • CHF
      • Structural heart disease
    • Hematocrit <30%
    • “Elderly”
    • Shortness of Breath
    • Systolic BP <90
    • (+1) Family history of sudden cardiac death

Step 4: Consider 6 Deadly Syncope Mimics

  • 15% of the following diseases reportedly present as “syncope”
    • AKA “Rule of 15s”
  • Subarachnoid hemorrhage
  • Myocardial infarction
  • Pulmonary embolism
  • Aortic dissection
  • Abdominal aortic aneurysm
  • Perforated GI
    • Ulcers
    • Ectopics

Additional Reading

STEMI

You have 90 minutes to restore blood flow.

Step 1: Obtain EKG and Call STEMI Alert

  • This activates ED resources as well as cath lab, interventional cardiology, etc

Step 2: Stop the Platelets

  • Dual anti-platelet therapy
    • Aspirin 325mg chewed (or PR)
    • Plavix 600mg (not usually given in ED)
      • Complicates management if patient needs CABG

Step 3: Stop the Coagulation Cascade

  • Heparin 60 units/kg (MAX 4000 units)

Step 4: Patient Should (Ideally) Be Going to Cath Lab By Now

  • If you DON’T have cath lab
    • Option 1: 30 minutes to give thrombolytics
    • Option 2: 120 minutes to get them to a different hospital with cath lab

Sgarbossa Criteria

  • Left bundle branch block (LBBB)
  • PLUS
  • Concordant ST elevation (>1mm) in leads with positive QRS
  • OR
  • Concordant ST depression (>1mm) in leads with negative QRS
    • Typically V1-V3
  • OR
  • Severely discordant ST elevation (>5mm) in leads with negative QRS

“MONA”

  • Morphine 4mg IV q5min PRN pain is appropriate if patient actually HAS pain
  • Oxygen has been shown to worsen outcomes if given indiscriminately
    • Not ideal to be giving supplemental O2 when SaO2 is 100%
  • Nitroglycerine
    • Nitroglycerine 0.4 mg SL q5min
    • OR
    • Nitroglycerin 10mcg/min drip (will need to be titrated UP)
      • For comparison…
        • 0.4 mg SL nitroglycerine releases approximately 80mcg/min
    • Contraindications
      • Inferior/Right heart infarction
        • Patients usually preload dependent
        • Nitro drops preload
      • Sildenafil (Viagra)
        • Can cause sudden/severe drop in blood pressure
      • Hypotension

Additional Reading

Chest Pain

There are six cardiopulmonary causes of chest pain that you need to know.

The SIX Causes

  • Cardiac
    • Acute coronary syndrome (ACS)
    • Pericarditis with tamponade
  • Pulmonary
    • Pneumonia
    • Pneumothorax
  • Vascular
    • Pulmonary embolism
    • Aortic dissection

Step 1: Core Measures

  • Aspirin
  • EKG

Step 2: Look for the “King” (Acute Coronary Syndrome)

  • Four high yield symptoms
    • Radiation to the RIGHT shoulder
    • Vomiting
    • Worsens with exertion
    • Diaphoresis

Step 3: Look for the “Queen” (Pulmonary Embolism)

  • Wells score
  • PERC rule

Step 4: Print a Previous Cath Report

  • Major bonus points with attending!
  • Other useful information
    • Previous echocardiograms
    • Previous stress tests
    • Previous CTAs for PE

Step 5: Basic Testing Plan

  • If concerned for cardiac causes
    • Troponin
  • If concerned for pulmonary causes
    • Chest x-ray
  • If concerned for vascular causes
    • CTA of the chest

Additional Reading

© 2020 EM Clerkship

Theme by Anders NorenUp ↑