ekg lead avr

EKG Lead aVr: What You DON’T Know May Kill Your

Patient

EKG Lead aVr: What You DON’T Know May Kill Your

PatientAndrew J. Bowman

Acute Care Nurse Practitioner

Fellow American College CV Nurses

Emergency Departments

Witham Health Services - Lebanon

IU Health Arnett - Lafayette

Disclosures

• No financial disclosures

EKG Club

• Co-Founder

• Facebook – 1500+ (1800+ as of today)

History EKG

• First recorded 1887 – Waller

• Clinical tool - Einthoven

Einthoven’s EKG

Leads

• Limb Leads

• Augmented Limb Leads

• Precordial Leads

Limb Leads & Augmented Limb Leads

Einthoven’s Triangle

Normal Ventricular Axis

Limb Leads

• I

• II

• III

Augmented Limb Leads

• aVr

• aVl

• aVf

Precordial Leads

• V1

• V2

• V3

• V4

• V5

• V6

Normal EKG

“Map’ of EKG

“Map’ of EKG

???

“Map” of EKG

Analogy

Lead aVr (or How Many View It)

Why EKG?

• Cardiac Problems

• Non-Cardiac Problems

Cardiac Problems

• Ischemia

• Injury

• Infarction

• Arrhythmia

• Cardiomyopathy

Non-Cardiac Problems

• Electrolyte Disorders

• Toxidromes

• Pulmonary Embolism

Lead aVr

• An augmented limb lead placed on right arm

• Most commonly used to assure proper limb lead placement

• Common belief rarely offers useful information “forgotten 12th lead”

“Forgotten 12th Lead”

11

Lead aVr

• Actual several good reasons to carefully evaluate lead aVr

Lead aVr

• STEMI / STEMI Equivalent

• SVT r/t WPW

• VT vs. SVT in WCT

• Pericarditis

• Na+ Channel Blocker Toxicity

STEMI

• ST segment Elevation Myocardial Infarction– A need to recognize pattern indicating acute

myocardial infarction and need for emergent reperfusion therapies (PCI preferred)

STEMI Patterns to Know

• Inferior

• Lateral

• Septal

• Anterior

• Posterior

STEMI Patterns to Know

Inferior STEMI

Lateral STEMI

Anterior-Septal STEMI

Inferior-Posterior STEMI

How is aVr Helpful in STEMI?

Case

• 64 year old man

• Hx MI, HTN, DM

• Left arm pain

Case EKG

What Do We See?

Case Progression

• ACS

• Widespread ST depression (STD)– STE aVr & aVl & V1

• ASA

• NTG

• Heparin

Case Evolution

• Admitted to ICU

• 8 Hours Later

• Cardiogenic Shock

• Died

STE Lead aVr

• In setting of ACS, STE Lead aVr– LMCA Stenosis– Proximal LAD Stenosis– Triple Vessel Disease

– All BAD!!!!

STE Lead aVr

• STE aVr + aVl = LMCA Stenosis

STE Lead aVr


• STE aVr > STE V1 = LMCA Stenosis

STE Lead aVr


• STE aVr > STE V1 = LMCA Stenosis

• Greater STE aVr, more likely LMCA Stenosis

ACS with LMCA Stenosis

• HIGH Mortality w/o PCI

• Medical Tx Does NOT Help!!

My Recent Case

• 47 yowm

• Chest pain and heart racing 1 hr PTA

• **Sweating**

• Hx smokes, HTN

• No Known CAD

Initial EKG

Initial Evaluation

• P - 178

• R - 24

• BP - 260/180

• SpO2 – 95%

• Pain – 2/10

• Given ASA, IV Cardizem

• Repeat EKG

Evolution

• HR Better

• Still CP 2/10

• NTG with Better BP

• EKG Repeated

Evolution 2

• Concern for STEMI or Equivalent

• Diffuse STD

• STE aVr

• STE V1

• Concern for “BADNESS”

Evolution 2

• Interventionalist Paged and to ER

• Patient to Cath Lab

• Returned 15 Minutes Later

• “Not STEMI” “LVH”

Evolution 3

• Initial Troponin 0.14 (0.10)

• Admitted

• AM Troponin 13.3!!

• Cath Lab

Cath Lab

• Triple Vessel Disease

Cath Lab

• Triple Vessel Disease

–“BADNESS”

Why Delay?

• Cardiologists are often behind the times

• Large percentage of STEMI EKG literature is from EM

• We have to “convince” cardiology

Next Case

• 85 yowm

• Chest Pain

• EKG

What Do We See?

• Widespread STD

• STE aVr

• STE aVl

Evolution

• Elevated Troponin

• Dx NSTEMI

• Admitted

• Continued to Have Pain!

Repeat EKG

STE aVr + deWinter ST-T

Lead aVr in STEMI

• In setting of ACS, STE Lead aVr– LMCA Stenosis

– Proximal LAD Stenosis– Triple Vessel Disease

– All BAD!!!!

How Else Is aVr helpful?

SVT w WPW

SVT with WPW

• 14 yowm

• Dizziness

• Healthy

• Exam – Tachycardia

• EKG

SVT

• STE Lead aVr with NCT likely to be WPW

• Confirm delta waves on post conversion EKG

• STE & STD in SVT are not Dx ischemia

How Else May We Use aVr?

VT vs SVT in WCT

Numerous Old Algorithms

• Brugada Criteria

• Wellens Criteria

• Akhtar Criteria

• Griffith Criteria

Brugada Criteria

• 4 step process– No RS complex all precordial leads?

– RS interval > 100ms in 1 precordial lead?

– AV dissociation?

– Morphology criteria for VT present in precordial leads V1-2 and V6?

Wellens Criteria

• QRS width > 0.14 secs

• Left axis deviation > -30°

• AV Dissociation

• Certain QRS configurations– RBBB type QRS

• Monophasic R, qR, QR, RS in V1• R/S < 1, monophasic R, QR, QS in V6

– LBBB type QRS• qR or Qs in V6

Akhtar Criteria

• AV Dissociation

• Positive QRS concordance

• QRS axis between –90° and +180°

• LBBB and rightward axis >90°

• RBBB and QRS > 0.14 secs

• LBBB and QRS > 0.16 secs

• QRS morphology during tachycardia different from baseline preexisting BBB

Griffith Criteria

• SVT diagnosed only if QRS morphology is typical of a BBB

– RBBB• rSR’ in V1 and RS in V6 with R/S > 1

– LBBB• rS or QS in V1 and V2 and delay to S nadir

< 70 msecs• R wave and no Q wave in V6

What Makes It Easy?

Old EKG!

New Algorithm

• Uses a SINGLE EKG lead

VT vs SVT Lead aVr (Verecki et al, January 2008, Heart Rhythm, 5/1)

WCT + SVT

WCT = VT

Notched QS = VT

What Else is aVr Helpful For?

Pericarditis

• Diffuse “global” STE or STD

• PR segment depression inferior leads

• PR segment elevation aVr

Pericarditis

Finally, What Else?

Na+ Channel Blocker Toxicity

• Amitriptyline• Chlorimipramine• Desipramine• Doxepin• Imipramine• Nortriptyline• Protriptyline

• Elavil• Clomipramine• Norpramin• Sinequan• Tofranil• Pamelor• Vivactil

TCA OD Effects

• AMS

• Hypotension

• Tachycardia

• Prolonged QRS, QTc

• Seizures

• Cardio-Respiratory Arrest

Terminal R Wave

TCA OD

Poorly Responsive Young Male

After Tx

TCA OD and What Else??

TCA “SALT”

• Shock

• AMS

• Long QRS & QTc

• Terminal R in Lead aVr

• “SALT” is also the cure NaHCO3

Lead aVr

• May be VERY helpful in…– STEMI

– SVT r/t WPW– VT vs SVT in WCT– Pericarditis– TCA OD

Handout

• Thanks to Michelle Lin, MD

• Academic Life in Emergency Medicine– ALiEM– academiclifeinem.com

• Paucis Verbis cards

Questions

• [email protected]

• Facebook “EKG Club”– Add your “cool” EKG’s and stump us

Web Sites

• ekgumem.tumblr.com Dr. Mattu’s

• ecg.bidmc.harvard.edu/maven Lots of EKG’s

• hqmeded-ecg.blogspot.com Dr. Smith

• ecgguru.com Free Downloads

• en.ecgpedia.org Comprehensive Overview

ekg lead avr

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