indiana ena 2011 tachyarrhythmias

INDIANAENA SYMPOSIUM

2011

Andrew J. Bowman

Acute Care Nurse Practitioner

Fellow – American College CV Nurses

Registered Nurse

Paramedic

Co-Founder

Yahoo Groups

Facebook

TACHYARRHYTHMIAS

What works…

What doesn’t…

What KILLS!!!

OVERVIEW

• Wide Complex Tachycardia (WCT)

• Ventricular Tachycardia (VT)

• Adenosine in WCT

• Wolff-Parkinson-White Syndrome

• The “walking-talking” VF patient

ACLS Algorithm

• 2010 AHA Guidelines for WCT

– Determine Stability

– Obtain 12 Lead EKG (if Stable)

– Regular or Irregular

ACLS Algorithm

• Regular WCT

– If confirm VT or SVT with Aberrancy

• Treat accordingly

– If not able to determine

• Adenosine likely safe to treat and/or diagnose

ACLS Algorithm

• Irregular WCT

– Atrial Fibrillation or Flutter

• Rate Control

• Rhythm Control

– Polymorphic VT

• Defibrillation Likely Needed

• Treat baseline long QTc if present

Wide Complex Tachycardia

• Definition

– ANY heart rhythm with…

– QRS duration >= 120ms (3 little boxes)

– Ventricular rate > 100bpm

– VERY BROAD & INCLUSIVE!!!

WCT• Differential Dx

– VT

– VT!!

–VT!!!– SVT with BBB

– SVT with Aberrant Conduction

– Paced Rhythms

– AV Re-Entrant Tachycardia with Antidromic Conduction

– Electrolyte Abnormalities

– Drug Toxicity (Na+ Channel Blockers)

Yes or No?

• EKG can reliably distinguish VT from SVT with BBB /aberrant conduction ?

Yes or No?

• EKG can reliably distinguish VT from SVT with BBB /aberrant conduction?

•NO!!!!!

Yes or No?

• EKG can reliably distinguish VT from SVT with BBB /aberrant conduction?

•NO!!!!!

• EKG rules IN VT

• Nothing reliably rules OUT VT

“BEST” Teaching

• Assume wide complex tachycardia (WCT) is VT until proven otherwise

• When in doubt, assume and treat WCT as VT

EKG Favors VT

• AV Dissociation

• Fusion Beats

• Left Axis or Right Axis

• Extreme Right Axis

• QRS > 140ms duration

• RS > 100ms

• Precordial Concordance

– (All UP or All DOWN)

Fusion

QRS > 140msRS > 100ms

Concordance

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?

Brugada Criteria

• 27 EKG’s with WCT

• 3 ED Physicians

• Applied Brugada Criteria

• 22% Intra-operator variability with OPEN BOOK TEST!!!

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

But What Did We Say???

• EKG can ONLY…

• Rule IN VT

• NOT…

• Rule OUT VT

VT or SVT with BBB

• Can only say SVT with BBB…IF…

• Tachycardia EKG QRS configuration

EXACTLY same as baseline EKG

QRS configuration

43 Male with Palpitations

43 Male, Asymptomatic

11th Commandment

• Thou shalt not give verapamil to WCT tachycardia!

•IT KILLS!!!!!!!

Clinical Information?

• Hemodynamic Status?

• Younger Age?

• No History Cardiac Disease?

•NO!!!!!

Adenosine (Adenocard)

• Can convert SOME VT

• Adenosine will NOT convert all SVT

• Adenosine responsive VT• Usually younger

• No prior known history cardiac disease

• SOUND FAMILIAR?????

Tx of VT

• Pulseless

• Unstable VT with Pulse

• Stable VT

Pulseless

• Treat as VF

• Defibrillate

Unstable VT with Pulse

• Synchronized Cardioversion

Stable VT

• Lidocaine?

• Amiodarone??

• Procainamide???

Lidocaine

• Poor success rate for converting VT to NSR

• 20-30%

Amiodarone

• “GOOD FOR EVERYTHING”

• Except…

Except Cardiac Arrest

• “There is no evidence that ANYantiarrhythmic drug given routinely during cardiac arrest increases survival to hospital discharge.” (Hazinski, Circulation, 2005)

Except Pregnancy

• Avoid amiodarone in pregnancy– The ONLY class D antiarrhythmic

– Fetal hypothyroidism, IUGR, fetal bradycardia, prematurity

– Only if other drugs fail

• Procainamide or Lidocaine preferred in pregnant patients with ventricular arrhythmias

Except A-Fib with WPW

• More on this later!

Except Torsades de Pointes

• TDP from prolonged QTc

– Further prolongs QTc and worsens TDP

– If baseline EKG has NORMAL QTc then it is not TDP, it is polymorphic VT

Young Woman - Syncope

Torsades de Pointes

Except “SLOW VT”

• WCT < 120-130bpm

– Think…

• AIVR

• Na channel blocker OD

• Hyperkalemia

“Slow VT”

Post - Tx

“Slow VT”

• Inappropriate Tx of “Slow VT” may cause ASYSTOLE

– WCT from hyperkalemia may be mis-Dx as VT

– AIVR may be mis-Dx as VT

– Tx with Lidocaine = ASYSTOLE!!

– Tx with Amiodarone = ASYSTOLE!!

Tx Slow VT

• Hyperkalemia

– NaHCO3

• TCA OD (Na+ Channel Blocker)

– NaHCO3

• AIVR

– Benign Neglect

So What to Use???

•Procainamide is

BACK!!!!!

Procainamide

• Excellent success ALL types of WCT’s

– VT

– SVT or Afib with BBB

– SVT or Afib with WPW

• When in doubt….…reach for procainamide

Procainamide Dosing

• 20 – 50 mg/min “bolus” until…

– Arrhythmia suppression

– Hypotension

– QRS widens > 50% baseline

– 17mg/kg total dose

• Then 1-4mg/min infusion

Wolff-Parkinson-White

• Pre-excitation of ventricles because of abnormal pathway of conduction that bypasses the AV node.

WPW

WPW

• EKG Findings

– Short PR interval

– Widened QRS

– Delta wave

– Repolarization changes

WPW

WPW Tachyarrhythmias

• Orthodromic Conduction

• Antidromic Conduction

• Atrial Fibrillation

Orthodromic

• Conduction down AVN then back through accessory pathway

• Narrow complex QRS (unless BBB)

Orthodromic Tx

• Adenosine

• Other AVN blockers

– Calcium blockers

– Beta blockers

Antidromic

• Conduction down accessory pathway then back through AVN

• Wide complex QRS

Antidromic Tx

• Adenosine

• Procainamide

A-Fib with WPW

• Atria 400-600 bpm

• AVN blocks many

• Accessory pathway still available

A-Fib with WPW

A-Fib with WPW

• Classic EKG Findings

– Irregularly-irregular (may be difficult to “eyeball”)

– Narrow and wide QRS morphology

– Portions “very fast” (>200-250bpm, may approach 300bpm)

A-Fib with WPW

WPW w A-Fib

WPW with A-Fib

WPW with A-Fib

WPW with A-Fib

A-Fib with WPW

• Atria at 400-600bpm

• If unopposed to ventricles

• Ventricles at 400-600bpm

–VF!!!

Tx A-Fib with WPW

• AVOID AV NODE BLOCKERS!!!!!

– A

– B

– C

– D

Tx A-Fib with WPW

• AVOID AV NODE BLOCKERS!!!!!

– A – Adenosine AND Amiodarone

– B – Beta Blockers

– C – Calcium Channel Blockers

– D - Digitalis

A-Fib, WPW & AV Nodal Blockers (The Problem)

• Is there evidence of irregularity?

• Is there evidence of changing QRS morphology?

• Are there sections of “very fast” ventricular rates?

A-Fib, WPW & AV Nodal Blockers (The Problem)

Pitfalls

• Patient with A-Fib with WPW

– Mis-Dx as SVT/VT & give adenosine

•VF

– Mis-Dx as A-Fib with BBB & give AVN blockers

•VF

AHA

• Still recommends Amiodarone for A-Fib in the setting of WPW

NO!!!!!• Amiodarone

– Class I (Na+)

– Class II (Beta)

– Class III (K+)

– Class IV (Calcium)

How to Tx?

• P-

• P-

How to Tx?

• Procainamide

• Propofol (or sedation of choice) and DCC.

“Walking-Talking” VF

“Walking-Talking” VF

• Medics sent for “weak & dizzy all over”

• BP cannot be obtained

• Pulse “hard to palpate” – “keep losing it”

• SpO2 80% and poor waveform

Arrival to ED

• Awake and talking

• Hoses entering chest wall

• Battery pack on waist

• Rhythm below

Walking-Talking 12 Lead

VAD

• Ventricular Assist Device

• Provides mechanical support for failing heart

• Support can be… hours…days…months…years

VAD

• Bridge to re-evaluation

• Bridge to recovery

• Bridge to transplant

• Bridge to destination therapy

VAD Patient

• Anti-coagulation

– Triple therapy

• Anti-arrhythmics

• Anti-hypertensives

VAD Types

• Pulsatile Flow

– Heartmate XVE

– Thoratec IVAD

• Non-Pulsatile Flow

– Heartmate II

Calling 911

• Lack of energy or weakness

• Symptoms may be vague

Outpatient Emergencies

• Arrhythmia

• Hemolysis

• Renal Failure

• Infection

• Decreased Preload from Dehydration

• GI Bleeding

Arrhythmia

• VAD’s do not affect EKG tracing

• Effects of Prolonged Arrhythmia

– Poor Perfusion

– Hypoxia

– Brain Damage

– Death

Who Has A VAD???

Arrhythmia

• VT / VF

– DEFIBRILLATE!!!!!

– May require sedation

– Disconnect VAD from wall outlet

No CPR for VAD’s

• Disruption of pump anastamosis site

• Fatal hemorrhage

• Call VAD Center

Summary

• WCT = Tx as VT until proven otherwise

• Adenosine probably safe for everything EXCEPT A-Fib with WPW

•NO AVN Blockers A-Fib with WPW

• VAD’s are more common

Thank You!!!!!