Supraventricular Arrhythmias

1
Supraventricular Arrhythmias

• Zayd A. Eldadah, MD, PhD
• Cardiac Arrhythmia Service
• The Georgetown University Hospital
• Washington DC
• Resident Rounds
• May 13, 2009

2
Objectives

• Understand basic cardiac electrophysiology
• Identify and classify the principal types of
  supraventricular arrhythmias
• Understand current therapy for these arrhythmias

3
Cardiac RhythmDifferential Diagnosis

• Normal Sinus Rhythm
• Bradyarrhythmias
• Tachyarrhythmias

4
Cardiac Rhythm

• Normal heart rate 60 99 beats/min
• Normal conduction sequence

Impulse arises in sinoatrial (SA) node ? Atrial
depolarization ? Impulse reaches atrioventricular
(AV) node ? Impulse travels down Bundle of
His ? Right Left Bundles ? Purkinje
fibers ? Ventricular depolarization
5
Normal Cardiac Conduction
6
Cardiac conduction system
7
Case 1
A 21-year-old woman presents to the ER for the
10th time in 5 years with palpitations and
dizziness. She is healthy and only takes oral
contraceptives. BP 120/80. Stable but
uncomfortable.
8
Case 1
A 21-year-old woman presents to the ER for the
10th time in 5 years with palpitations and
dizziness. She is healthy and only takes oral
contraceptives. BP 120/80. Stable but
uncomfortable.

• The appropriate next step in management would be
• Refer for permanent pacemaker implantation
• Administer atropine 1mg iv
• Begin metoprolol 25 mg daily
• Administer adenosine 6mg iv

9
Case 1
A 21-year-old woman presents to the ER for the
10th time in 5 years with palpitations and
dizziness. She is healthy and only takes oral
contraceptives. BP 120/80. Stable but
uncomfortable.

• The appropriate next step in management would be
• Refer for permanent pacemaker implantation
• Administer atropine 1mg iv
• Begin metoprolol 25 mg daily
• Administer adenosine 6mg iv

10
Case 1 part 2
Her tachycardia abruptly terminates, and sinus
rhythm is restored. She is comfortable.

• The most appropriate next step in management
  would be
• Begin amiodarone 200mg orally daily
• Refer for catheter ablation
• Discontinue oral contraceptives
• Begin nifedipine 25mg sublingually daily

11
Case 1 part 2
Her tachycardia abruptly terminates, and sinus
rhythm is restored. She is comfortable.

• The most appropriate next step in management
  would be
• Begin amiodarone 200mg orally daily
• Refer for catheter ablation
• Discontinue oral contraceptives
• Begin nifedipine 25mg sublingually daily

12
Narrow-complex tachycardias
13
Narrow-complex tachycardias

• Rate gt 100 beats per minute
• QRS duration lt 120 msec

14
Narrow-complex tachycardias
Originate in the atria (or adjoining veins)
or
Depend on the AV junction
15
Narrow-complex tachycardias

• AV junction
• AV nodal reentrant tachycardia (AVNRT)
• AV reciprocating tachycardia (AVRT) (accessory
  pathway)
• Junctional ectopic tachycardia
• Non-paroxysmal junctional tachycardia

• Atrial
• Sinus tachycardia
• Inappropriate sinus tachycardia
• Sinus node reentrant tachycardia
• Atrial fibrillation
• Atrial flutter
• Atrial tachycardia
• Multifocal atrial tachycardia

16
Narrow-complex tachycardiasa systematic approach

• Review the clinical data
• Recognize at first glance
• Find the P wave
• Match Ps and QRSs
• Pinpoint the diagnosis
• Confirm

17
Narrow-complex tachycardiasrecognize at first
glance
18
Narrow-complex tachycardiasrecognize at first
glance
19-year-old asthmatic woman with extreme dyspnea
19
Sinus tachycardiarecognize at first glance

• The most common SVT
• Overall P wave axis morphology normal.
• Atrial rate 100-200.
• 11 P-to-QRS relationship
• Short PR interval (high catecholamine tone)
• Underlying condition, not rhythm, must be
  addressed (e.g., beta-blockade deleterious in
  this case)

19-year-old asthmatic woman with extreme dyspnea
20
Narrow-complex tachycardiasrecognize at first
glance (contd)
ATRIAL FIBRILLATION
21
Narrow-complex tachycardiasrecognize at first
glance (contd)
ATRIAL FIBRILLATION

• Results from multiple reentrant atrial wavelets
• Often no discernable P waves
• Atrial rate 300-600
• Atrial rate gtgt ventricular rate
• Irregularly irregular ventricular response

22
Atrial Fibrillation
23
Case 345 year-old with lone, paroxysmal atrial
fibrillation, no episodes of rapid ventricular
response

• Essential management in this patient includes
• Plavix
• Metoprolol
• Coumadin or Aspirin
• Amiodarone
• None of the above

24
Case 345 year-old with lone, paroxysmal atrial
fibrillation, no episodes of rapid ventricular
response

• Essential management in this patient includes
• Plavix
• Metoprolol
• Coumadin or Aspirin
• Amiodarone
• None of the above

25
AFFIRM trialAtrial Fibrillation Follow-up
Investigation of Rhythm Management

• 4060 patients with atrial fibrillation randomized
  to rate control only vs. rhythm control
• Age 65
• At least one risk factor for stroke/death (e.g.,
  LA enlargement, HTN, DM, CHF, prior TIA, LV
  dysfxn)
• Primary endpoint all-cause mortality
• Composite secondary endpoint death, disabling
  stroke or anoxic encephalopathy, major bleeding,
  cardiac arrest

Wyse et al. N Engl J Med. 2002347 1825-33.
26
AFFIRM Results
63 in sinus at 5 yrs
35 in sinus at 5 yrs
Wyse et al. N Engl J Med. 2002347 1825-33.
27
Summary AFFIRM

• Rhythm control is not superior to rate control in
  AF.
• Rate control can be primary therapy for the
  elderly or high-risk patients

28
J Am Coll Cardiol. 200648 854-906
29
Management of AF in 2008

• Thrombosis control
• Warfarin or aspirin for all patients who have at
  least one moderate stroke risk factor (CHAD score
  1)
• Moderate risk factors CHF, hypertension, age ?
  75, DM)
• Warfarin for all patients with more than one
  moderate or any high risk factor
• High risk factors prior TIA or CVA or embolic
  event, mitral stenosis, prosthetic valve

30
Management of AF in 2008

• Rate control
• beta-blockers, calcium-channel blockers,
  digitalis, AV node ablation permanent pacemaker
• Rhythm control to relieve symptoms
• Begin with drug therapy
• In absence of structural heart disease
  propafenone, flecanide
• In pregnancy procainamide
• With structural heart disease amiodarone
• When drugs fail, proceed to catheter ablation

31
AF Initiation
b
b
32
Left atrial catheter ablation
Isolate both pairs of veins plus mitral isthmus
and posterior atrial ablation
33
Narrow-complex tachycardiasrecognize at first
glance (contd)
ATRIAL FLUTTER
34
Narrow-complex tachycardiasrecognize at first
glance (contd)
ATRIAL FLUTTER

• Usually result of single large reentrant circuit
• Often without structural heart disease
• Atrial rate 250-350
• Atrial rate gt ventricular rate
• AV block may vary (e.g. 21, 41)

35
Atrial Flutter
36
Atrial Flutter
37
Halo Catheter
20
1
38
Flutter Termination
39
Confirmation of Isthmus Block
40
Atrial Flutter Ablation

• Ablation of the cavo-tricuspid isthmus
• Goal complete conduction block across the
  isthmus
• Recurrence rate of typical atrial flutter when
  isthmus block achieved lt5

41
Major SVT types
AV Nodal Reentrant Tachycardia (AVNRT)
AV Reciprocating Tachycardia (AVRT)
Atrial Tachycardia
accessory pathway
42
Narrow-complex tachycardiasa systematic approach

• Review the clinical data
• Recognize at first glance
• Find the P wave
• Match Ps and QRSs
• Pinpoint the diagnosis
• Confirm

43
RP Classification of SVTs
Short RP (RPltPR)
Long RP (RPgtPR)

• Typical AVNRT
• AVRT (accessory pathway)
• Non-paroxysmal junctional tachycardia

• Sinus tachycardia
• Sinus node reentry
• Atrial tachycardia
• Atypical AVNRT
• Permanent junctional reciprocating tachycardia
  (PJRT)
• Non-paroxysmal junctional tachycardia

44
32-year-old with recurrent palpitations
AV NODAL REENTRANT TACHYCARDIA (AVNRT)
45
AVNRT
46
EP Cathetersgetting the full picture
HRA high right atrium
Coronary Sinus
His
RV
47
Typical AV nodal reentrant tachycardia (AVNRT)
Pseudo R

• Occurs at any age (FgtM)
• Short VA time (lt90ms)
• Pseudo R or no visible P wave (buried in QRS)
• Atrial rate 150-250
• 11 P-to-QRS
• No delta wave
• Adenosine-sensitive

48
Typical AVNRTAV nodal reentrant circuit
short refractory period
First-line treatment for symptomatic
patients Catheter ablation
long refractory period
49
Typical AVNRT
50
Ablation of AVNRT

• Ablation site
• Near CS os
• Small M shaped atrial EGM
• Large ventricular EGM

51
AVNRT Ablation

• Ablation of the slow pathway of the AV node
• Goal preservation of the single, fast pathway of
  AV conduction
• Recurrence rate of AVNRT post ablation lt5
• Risk of complete heart block 1

52
26-year-old with PSVT
53
AV reciprocating tachycardia (AVRT)Baseline ECG
Wolff-Parkinson-White Syndrome

• Accessory pathway connects A V
• AP may be manifest (pre-excitation) or concealed
  (conducts retrograde)
• WPW characterized by pre-excitation at baseline
  with PSVT
• In SVT, atrial rate 150-200

short PR interval
delta wave
54
AV reciprocating tachycardia (AVRT)Baseline ECG
Wolff-Parkinson-White Syndrome
short PR interval
delta wave
Mid-septal, right-sided accessory pathway
55
Narrow-complex tachycardiasrecognize at first
glance
WOLFF-PARKINSON-WHITE SYNDROME
short PR interval
delta wave
Left free wall accessory pathway
56
AVRT (accessory pathway-mediated SVT)
57
AVRT Circuits
Orthodromic Reentrant Tachycardia (ORT)
Antidromic Reentrant Tachycardia (ART)
First-line treatment for symptomatic
patients Catheter ablation
Atrial Fibrillation
58
Accessory Pathway Ablation
59
Accessory Pathway Ablation

• Curative therapy for WPW and concealed accessory
  pathways
• Bypass tract sites
• Left free wall (60)
• Postero-septal (30)
• Right free wall (9)
• Antero-septal (1)
• Recurrence rate of AVRT post-ablation lt5-10

60
Atrial Tachycardia Ablation
61
Atrial Tachycardia

• Atrial rate 150-240
• Regular rhythm
• Long RP interval
• P wave morphology or axis usually different from
  sinus
• Multifocal (MAT) 3 morphologies
• Isoelectric baseline between P waves
• Typically terminates with a QRS
• Ventricle not necessary for the circuit

Adenosine given
62
Atrial Tachycardia Ablation
63
Left Atrial Tachycardia AblationFacilitated by
3-D Electroanatomic Mapping
64
Atrial Tachycardia Ablation

• Common ectopic atrial tachycardia sites
• Crista terminalis
• Valvular annuli
• Pulmonary vein ostia
• Coronary sinus ostia
• Recurrence rate of AT post-ablation lt10

65
Summary

• SVTs are very common.
• Though rarely life-threatening, they can be very
  troublesome.
• Atrial fibrillation is the most common pahologic
  arrhythmia.
• Catheter ablation is first-line therapy for many
  SVTs along

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Wide-complex tachycardias

• Rate gt 100 beats per minute
• QRS duration gt 120 msec

68
Wide-complex tachycardias
69
Wide-complex tachycardias

• Atrial
• Any SVT with aberrant conduction (bundle-branch
  block)
• Any SVT conducting over an accessory pathway
  (e.g., atrial fibrillation in WPW)

• Ventricular
• Ventricular fibrillation
• Torsades de pointes
• Ventricular tachycardia (monomorphic, idiopathic)
• Accelerated idioventricular rhythm (AIVR)
• Pacemaker-mediated tachycardia

70
Wide-complex tachycardiasa systematic approach

• Review the clinical data
• Recognize at first glance
• Find the P wave
• Match Ps and QRSs
• Pinpoint the diagnosis
• Confirm

71
Wide-complex tachycardiasrecognize at first
glance
72
Wide-complex tachycardiasrecognize at first
glance

• Undulating QRS amplitude (twisting of the
  points)
• Occurs in prolonged QT (congenital or
  drug-related)
• Rate gt 200
• High risk of sudden death

A 72-year-old woman with coronary artery disease
and depression admitted with nausea and
lightheadedness
Torsades-de-pointes ventricular
tachycardia (patient on tricyclic, baseline QT
710 ms)
73
Wide-complex tachycardiasrecognize at first
glance
67-year-old man one hour after presenting w/STEMI
VENTRICULAR FIBRILLATION

• Results from multiple reentrant wavelets in the
  ventricle
• Usually occurs with structural heart disease
• Rate gt 300
• Rapidly lethal if not defibrillated

74
Ventricular arrhythmia
SCAR
75
Wide-complex tachycardiasWhats left? . . .
Distinguishing VT from SVT with aberrant
conduction
76
Wide-complex tachycardiasSVT with aberrancy

• Nodal Tachycardias
• AVNRT
• Automatic junctional tachycardia
• AVRT (AP mediated)

• Atrial rhythms
• Atrial tachycardia
• Sinus tachycardia
• Atrial flutter
• Atrial fibrillation

LBBB
RBBB
77
Wide-complex tachycardiasVT versus SVT with
aberrancy

• Probability
• Unselected patients with WCT 80 VT
• Patients with heart disease and WCT 95 VT

78
Wide-complex tachycardiasVT versus SVT with
aberrancy

• Clinical pearls
• VT can be associated with a normal blood
  pressure.
• Misdiagnosing SVT as VT is generally benign.
• The reverse can be catastrophic.
• Agents to treat SVT (e.g., verapamil or
  diltiazem) may precipitate hemodynamic collapse
  in VT.

79
VT versus SVT with aberrancyFind the P wave /
Match Ps QRSs

• AV dissociation virtually diagnostic of VT
• But only apparent in 1/3 of WCT due to VT
• Capture and fusion beats seen in VT
• When a dissociated P wave causes total (capture)
  or partial (fusion) activation of the ventricle
  in advance of the next beat

80
66 yo man with palpitations and syncope

• Regular rhythm 120 beats/min
• Wide QRS
• AV dissociation

81
VT versus SVT with aberrancyCloser look at QRS
Axis

• Normal QRS axis suggests SVT with aberrant
  conduction
• Left- or right-axis deviation favors VT
• Extreme left- or right-axis deviation strongly
  suggests VT

VT
0o
SVT
82
VT versus SVT with aberrancyCloser look at QRS
Morphology (contd)

• LBBB WCT VT is suggested by

notch
R gt 30 ms
S gt 70 ms
83
VT versus SVT with aberrancyConfirm

• Termination or increased AV block with carotid
  sinus massage, other vagal stimulation suggests
  SVT.
• Adenosine-induced termination suggests SVT.
• But some VTs are adenosine sensitive
• Response to other antiarrhythmic drugs generally
  not helpful
• EPS can provide definitive confirmation if WCT is
  inducible.

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Diagnostic EP study

• Unexplained syncope in the presence of structural
  heart disease
• Documented wide-complex tachycardia
• Prior sudden cardiac death
• Sustained supraventricular arrhythmias and PSVT
• Prior to, and in association with, catheter
  ablation procedures
• Risk stratification of patients with impaired
  ventricular function, NSVT, and a prior MI
  (EFgt30).

86
VT flavors

• Monomorphic VT
• Idiopathic VT
• Accelerated idioventricular rhythm (AIVR)

87
Monomorphic VT

• Arises from the ventricle (usually infarct scar)
• Rate 140-250
• Regular wide QRS
• High risk of sudden death, especially in poor LV
  function

Dissociated P waves
88
Idiopathic VTarising from RV outflow tract

• Usually from RVOT (LBBB morphology)
• Occurs with increased sympathetic tone (exercise)
• Patients have normal LV function
• Rate 140-220
• Regular wide QRS
• Benign arrhythmia, good prognosis

89
Accelerated Idioventricular Rhythm (AIVR)

• Arises from ventricle (Purkinje fibers)
• Generally peri-infarct rhythm
• Rate 60 120
• Regular, wide QRS
• Generally self-terminating
• Not necessarily an indicator of reperfusion

Retrograde P waves
90
Wide-complex tachycardiasSummary

• Consider all wide-complex tachycardia VT until
  proven otherwise.
• In unselected patients with WCT, 80 are VT.
• In patients with heart disease, 95 are VT.
• VT can be associated with a normal BP.
• ECG criteria to distinguish VT from SVT are not
  100 sensitive specific.

91
Ventricular ArrhythmiasAvailable Management
Options

• No treatment
• Pharmacologic therapy
• Catheter ablation
• Implantable Cardioverter Defibrillator (ICD)

92
Case 4

• A 60 year old woman had an MI three months ago.
  Her LVEF is 25, and she has moderate heart
  failure symptoms. She is currently managed on
  atenolol 50 mg qd, enalapril 5 mg bid, and
  aspirin. Her cardiologist orders a Holter
  monitor, which shows normal sinus rhythm with
  occasional PVCs and brief runs of nonsustained
  VT. The most appropriate management would be

• a. Double atenolol dose.
• b. Discontinue atenolol, and start amiodarone.
• c. Refer for ICD implantation.
• d. Refer for EP study, and if sustained VT is
  inducible, then ICD implantation.
• e. No change in management is indicated.

93
Case 4

• A 60 year old woman had an MI three months ago.
  Her LVEF is 25, and she has moderate heart
  failure symptoms. She is currently managed on
  atenolol 50 mg qd, enalapril 5 mg bid, and
  aspirin. Her cardiologist orders a Holter
  monitor, which shows normal sinus rhythm with
  occasional PVCs and brief runs of nonsustained
  VT. The most appropriate management would be

• a. Double atenolol dose.
• b. Discontinue atenolol, and start amiodarone.
• c. Refer for ICD implantation.
• d. Refer for EP study, and if sustained VT is
  inducible, then ICD implantation.
• e. No change in management is indicated.

94
Implantable Cardioverter Defibrillator (ICD)

• Originally to prevent sudden cardiac death in
  patients who already suffered SCD twice!
• First implant in 1980

Principal inventor Michel Mirowski 1924-1990
95
ICDs

• Implanted like a pacemaker
• Battery longevity 5 years
• Recognizes stops VF w/ shock
• Recognizes stops VT w/ anti-tachycardia pacing
  or shock
• All have pacing capability
• ICD types
• single-chamber (RV)
• dual-chamber (RA RV)
• biventricular (RA RV CS) (coronary sinus to
  pace the LV)

96
MADIT II(Multicenter Automated Defibrillator
Implantation Trial)ICDs as primary prevention
97
MADIT-IIResults
31 reduction in mortality in ICD group.
Moss et al. N Engl J Med 2002 346 877
98
Implantable Cardioverter Defibrillator
(ICD)indications for prophylactic implantation

• Ischemic cardiomyopathy EF30

What about non-ischemic cardiomyopathy?
99
SCD-HeFT(Sudden Cardiac Death in Heart Failure
Trial)

• 2521 patients in Class II-III HF, EFlt35
  (ischemic non-ischemic)
• Randomized to

Conventional therapy amiodarone
Conventional therapy placebo
Conventional therapy ICD
100
SCD-HeFTResults
Bardy GH et al. N Engl J Med 2005 352225-237
101
Conclusions

• Patients with Class II or worse HF an EF 35
  live longer with ICDs than without ICDs.

102
Case 5
A 50-year-old man collapses while crossing the
street. CPR is started, and paramedics arrive to
find him in VF. He is defibrillated, intubated,
then soon extubated in the CCU. ECG now shows
sinus rhythm with LBBB. Echo dilated
cardiomyopathy with LVEF 30. Cardiac cath no
coronary artery disease. He has no prior history
of syncope or heart failure symptoms. The most
appropriate next step is

• a. Double atenolol dose.
• b. Discontinue atenolol, and start amiodarone
• 400 mg bid for 2 weeks, then 200 mg qd.
• c. Refer for ICD implantation.
• d. Refer for EP study, and if sustained VT is
  inducible, then ICD implantation.
• e. No change in management is indicated.

103
Case 5
A 50-year-old man collapses while crossing the
street. CPR is started, and paramedics arrive to
find him in VF. He is defibrillated, intubated,
then soon extubated in the CCU. ECG now shows
sinus rhythm with LBBB. Echo dilated
cardiomyopathy with LVEF 30. Cardiac cath no
coronary artery disease. He has no prior history
of syncope or heart failure symptoms. The most
appropriate next step is

• a. Double atenolol dose.
• b. Discontinue atenolol, and start amiodarone
• 400 mg bid for 2 weeks, then 200 mg qd.
• c. Refer for ICD implantation.
• d. Refer for EP study, and if sustained VT is
  inducible, then ICD implantation.
• e. No change in management is indicated.

104
AVID TrialAntiarrhythmics Versus Implantable
Defibrillators

• Objective Determine the relative efficacy of ICD
  versus anti-arrhythmic drug therapy in patients
  with aborted sudden death or hemodynamically
  unstable VT.
• Inclusion Aborted SCD, sustained VT with
  syncope, or hemodynamically unstable VT with EF lt
  40.
• Study design Multi-center randomized parallel
  group study of 1016 patients (prematurely
  terminated). Randomized to ICD vs. drug (amio or
  sotalol).
• Patient population age 65 years, EF 31, CAD in
  81, SCD in 45

NEJM 1997 337 1576.
105
AVID Results
ICDs reduced mortality by 39, 31 at 3 yrs
NEJM 1997 337 1576.
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107
Case 3part 245 year-old with lone, paroxysmal
atrial fibrillation, no episodes of rapid
ventricular response

• A rhythm control strategy is superior to simply a
  rate control strategy in this patient
• True
• False

108
Case 3part 245 year-old with lone, paroxysmal
atrial fibrillation, no episodes of rapid
ventricular response

• A rhythm control strategy is superior to simply a
  rate control strategy in this patient
• True
• False

109
AFFIRM trialAtrial Fibrillation Follow-up
Investigation of Rhythm Management

• 4060 patients with atrial fibrillation randomized
  to rate control only vs. rhythm control
• Age 65
• At least one risk factor for stroke/death (e.g.,
  LA enlargement, HTN, DM, CHF, prior TIA, LV
  dysfxn)
• Primary endpoint all-cause mortality
• Composite secondary endpoint death, disabling
  stroke or anoxic encephalopathy, major bleeding,
  cardiac arrest

Wyse et al. N Engl J Med. 2002347 1825-33.
110
AFFIRM Results
63 in sinus at 5 yrs
35 in sinus at 5 yrs
Wyse et al. N Engl J Med. 2002347 1825-33.
111
Summary AFFIRM

• Rhythm control is not superior to rate control in
  AF.
• Rate control can be primary therapy for the
  elderly or high-risk patients

112
J Am Coll Cardiol. 200648 854-906
113
Management of AF in 2008

• Thrombosis control
• Warfarin or aspirin for all patients who have at
  least one moderate stroke risk factor
• Moderate risk factors age ? 75, hypertension,
  CHF, DM, LVEF 35
• Warfarin for all patients with more than one
  moderate or any high risk factor
• High risk factors prior TIA or CVA or embolic
  event, mitral stenosis, prosthetic valve

114
Management of AF in 2008

• Rate control
• beta-blockers, calcium-channel blockers,
  digitalis, AV node ablation permanent pacemaker
• Rhythm control to relieve symptoms
• Begin with drug therapy
• In absence of structural heart disease
  propafenone, flecanide
• In pregnancy procainamide
• With structural heart disease amiodarone
• When drugs fail, proceed to catheter ablation

115
Case 6
A 30-year-old man presents to the emergency room
with palpitations and lightheadedness. 12-lead
ECG is shown below. His blood pressure is 120/70.
All of the following treatment options would be
appropriate EXCEPT
116
Case 6
A 30-year-old man presents to the emergency room
with palpitations and lightheadedness. 12-lead
ECG is shown below. His blood pressure is 120/70.
All of the following treatment options are
appropriate EXCEPT

• a. Adenosine 12 mg iv
• b. Lidocaine 100 mg iv
• c. Carotid sinus massage
• d. Valsalva maneuver
• e. Verapamil 10 mg iv

117
Case 6
A 30-year-old man presents to the emergency room
with palpitations and lightheadedness. 12-lead
ECG is shown below. His blood pressure is 120/70.
All of the following treatment options are
appropriate EXCEPT

• a. Adenosine 12 mg iv
• b. Lidocaine 100 mg iv
• c. Carotid sinus massage
• d. Valsalva maneuver
• e. Verapamil 10 mg iv