Tachycardias or… “slow down, you move too fast” Susan P. Torrey, M.D., FACEP, FAAEM Associate Professor of Emergency Medicine Tufts University School of Medicine Baystate Medical Center, Springfield, Mass

Objectives Review diagnostic criteria of tachycardias Consider the diagnostic grid Answer several interesting questions What’s the scariest atrial fib you’ll ever see? Let’s use adenosine – it’s safe, isn’t it? How DO you know if it’s v. tach? Review more sneaky rhythm strips

Rate Rate = 300 ÷ # “big boxes” between R-R 300 – 150 – 100 – 75 – 60 – 50

Rate?

Rate? 1. Between 150 - 300 2. 75 x 3 = 225

Normal conduction

Wolff-Parkinson-White x short PR delta wave increase QRS width

Sinus tachycardia normal P before every QRS upright P in lead II Max. heart rate = 220/minute – age in years

Sinus tachycardia Common causes: compensation for shock - dehydration, hemorrhage, sepsis fever drugs (cocaine) acute pulmonary embolism thyrotoxicosis anxiety - needs to be dx of exclusion

19 yo male with multi-drug OD

Atrial fibrillation no discernible P waves - atrial activity is fibrillatory waves (f) - fibrillatory waves – II and V1 ventricular rhythm is irregularly irregular - untreated ventricular rate 100 – 180/min

Atrial fibrillation

Atrial flutter atrial activity – regular deflections (F waves) - F waves usually 300/minute rate and regularity of QRS variable - in purest form, multiple of 300

Atrial flutter untreated, flutter usually has 2:1 AV block  regular rhythm at 150/minute

Rate of 150… when the rate is 150/minute  always consider 2:1 atrial flutter

Multifocal atrial tachycardia P waves of varying morphology (≥ 3 foci) - absence of single dominant P wave Variable PP, RR, PR intervals - the other irregularly irregular rhythm Seen with COPD, elderly, seriously ill

Supraventricular tachycardia Regular, narrow tachycardia 2° re-entry AV nodal re-entry vs. AV re-entry (bypass) Onset and termination is abrupt Heart rate 140-220/minute Differential: sinus tach, 2:1 flutter, ? a fib

Reentry mechanism “fast” pathway rapid conduction time “slow” pathway long refractory period “slow” pathway slow conduction short refractory

SVT

Pseudo-S waves with AVNRT Pseudo-S waves disappear with sinus rhythm

another SVT…

AV reentry tachycardia? QRS alternans Prolonged RP interval

AV Reentry Tachycardia (WPW?)

after cardioversion!

Ventricular tachycardia Abnormal wide QRS Regular rhythm – “dead regular” Rate usually 140-200/minute

Wide-complex tachycardia 70% of WCT is ventricular tachycardia differential includes… SVT with aberrancy SVT with pre-existing bundle branch block SVT with bypass tract

Diagnostic grid - tachycardias Regular Irregular Narrow Wide

Diagnostic grid - tachycardias Regular Irregular Narrow Sinus tach SVT 2:1 flutter Wide

Diagnostic grid - tachycardias Regular Irregular Narrow Sinus tach SVT 2:1 flutter Atrial fib MAT Wide

Diagnostic grid - tachycardias Regular Irregular Narrow Sinus tach SVT 2:1 flutter Atrial fib MAT Wide V. tach SVT with…

Diagnostic grid - tachycardias Regular Irregular Narrow Sinus tach SVT 2:1 flutter Atrial fib MAT Wide V. tach SVT with… Atrial fib with…

Question #1

What is the scariest atrial fibrillation you will ever see? 38-year-old man with history of palpitations

Or this…

Scary atrial fib Atrial fib with… - aberrancy - pre-existing bundle, or… - bypass tract with Wolff-Parkinson-White ! - changing QRS shape and rapid conduction

Atrial fib with WPW most AV node blockers ↑ bypass conduction must avoid A – B – C – D A – adenosine B – beta-blockers C – calcium-channel blockers D – digoxin treat with electricity or procainamide

What about amiodarone? 2005 ACLS – rec: amiodarone 2010 ACLS – returns to procainamide Simonian S Inter Emerg Med 2010 Literature review challenges superiority and safety of amiodarone for atrial fib with WPW Complex drug with effects on Na+, K+, and Ca++ channels, as well as α- and β-blocking effects

rapid atrial fib with wide complex after cardioversion after ablation of bypass tract

Question #2

Let’s use adenosine…it’s safe isn’t it? Adenosine (Adenocard®) an α1 receptor agonist rapid onset and brief duration frequent side-effects: facial flushing, chest pressure, dyspnea

SVT conversion with adenosine

Adenosine

Beware proarrhythmias ! Torsade de pointe Precipitates atrial fib and flutter Protracted bradycardia and asystole 2:1 flutter  1:1 conduction Mallet Emerg Med J 2004

SVT at 140 ? Adenosine 6 mg IV 1:1 atrial flutter at 280/minute

Adenosine as diagnostic tool SVT Atrial flutter Sinus tach Ventricular tach converts to sinus reveals flutter waves reveals P waves nothing !

pediatric tachycardia 8-month-ago child with hx cardiac surgery as infant; parents say child is “fussy” HR 300/minute Adenosine…

Pre-hospital tachycardia

Question #3

How do you know if it’s V. tach?

How do you know if it’s V. tach? EKG criteria favoring V. Tach AV dissociation

AV dissociation

How do you know if it’s V. tach? EKG criteria favoring V. Tach AV dissociation QRS concordance all chest leads (V1-6) predominantly negative

QRS concordance

How do you know if it’s V. tach? algorithms Brugada’s four-step algorithm  98% sens / 96% spec Circ 1991 Vereckei’s new “simplified” algorithm Euro Heart J 2007

How do you know if it’s V. tach? clinical predictors association with heart disease or MI  98% positive predictive value Aktar Ann Intern Med 1988

It’s v. tach!

sneaky rhythms

1. 68-year-old woman with COPD complains of palpitations and nausea. Irregularly irregular  a. fib vs. MAT

2. 38-year-old woman complains of palpitations and weight loss. Regular, narrow  SVT vs sinus tach

3. 70-year-old woman with weakness. PMH: Parkinson’s Disease Regular…but fibrillatory waves?

4. 72-year-old man with palpitations, weakness, and chest discomfort.

after adenosine… F

5. 65-year-old man with palpitations and shortness of breath.

wide-complex, irregularly irregular  yikes after Amiodarone… then spontaneously converted to sinus

6. 56-year-old man with lung cancer from oncology clinic with SOB.

Irregularly irregular at 185/min Now 145/minute, and…

7. 75-year-old man from nursing home with altered mental status.

Appropriate DDD pacer function – essentially sinus tach

8. 65-year-old woman with dyspnea and chest pain.

Emergency Department EKG

After diltiazem…

9. 70-year-old man with palpitations and SOB

Close-up of III and aVF

After adenosine…oops!

10. 65-year-old woman after syncope.

After spontaneous conversion

Pseudo-S waves of AVNRT

11. 70-year-old man with chest pain 90/60, 200, 28, 92%

After electrical cardioversion…

12. 72-year-old woman “heart racing” EMS gave Amiodarone

ED 12-lead – 15 minutes later

15 min later…spontaneous conversion

In conclusion… Remember, tachycardias are easy… Narrow or wide complex? Regular or irregular?

Diagnostic grid - tachycardias Regular Irregular Narrow Sinus tach SVT 2:1 flutter Atrial fib MAT Wide V. tach SVT with… Atrial fib with…

In conclusion… Remember, tachycardias are easy… Narrow or wide complex? Regular or irregular? If the rate is around 150 think 2:1 flutter.

In conclusion… Remember, tachycardias are easy… Narrow or wide complex? Regular or irregular? If the rate is around 150  think 2:1 flutter. Use Adenosine, but respect it.

In conclusion… Remember, tachycardias are easy… Narrow or wide complex? Regular or irregular? If the rate is around 150  think 2:1 flutter. Use Adenosine, but respect it. Rapid wide-complex atrial fib  think WPW… Avoid A – B – C – D (and amiodarone)

In conclusion… Remember, tachycardias are easy… Narrow or wide complex? Regular or irregular? If the rate is around 150  think 2:1 flutter. Use Adenosine, but respect it. Rapid wide-complex atrial fib  think WPW… Treat wide-complex tachycardia per ACLS