Download Cardiac Arrhythmias

Cardiac Arrhythmias
Liu Pinming(刘品明), M.D., Ph.D.,
Department of Cardiology
Second Affiliate Hospital
Sun Yat-sen University
Useful Expressions
Cardiac arrhythmias
心律失常
Sinus arrhythmia
窦性心律失常
Antiarrhythmic drugs
抗心律失常药
Atrial premature beat (APBs)
房性早搏
Atrioventricular junctional premature beat
房室交界性早搏
Ventricular premature beat (VPBs)
室性早搏
Useful Expressions
Paroxysmal supraventriculat tachycardia (SVT)
阵发性室上性心动过速
Atrioventricular nodal reentrant tachycardia (AVNRT)
房室结内折返性心动过速
Atrioventricular reentrant tachycardia (AVRT)
房室折返性心动过速
Atrial tachycardia
房性心动过速
Atrial reentrant tachycardia
房性折返性心动过速
Autonomic atrial tachycardia
自律性房性心动过速
Chaotic/Multifocal atrial tachycardia
紊乱性/多源性房性心动过速
Useful Expressions
Proxysmal ventricular tachycardia (VT)
Nonsustained VT (lasting for < 30 s)
Sustained VT (lasting for ≤ 30 s)
Atrial flutter
Atrial fibrillation
Ventricular flutter
Ventricular fibrillation
阵发性室速
非持续性室速
持续性室速
心房扑动
心房颤动
心室扑动
心室颤动
Useful Expressions
Pre-excitation (Wolff-Parkinson-White) syndrome
预激综合征(WPW)
Sinus bradycardia
窦性心动过缓
Sinus arrest/standstill
窦性停搏
Sinoatrial block
窦房阻滞
Sick sinus syndrome, SSS
病窦综合征
Bradycardia-tachycardia syndrome
慢-快综合征
Useful Expressions
Atrioventricular block (AVB) 房室传导阻滞
Intraventicular block
Aberrant conduction
Bundle branch block
Bigeminy/ Trigeminy
Tachyarrhythmias
Bradyarrhythmias
室内传导阻滞
传导阻滞
束支阻滞
二联律/三联律
快速型心律失常
缓慢型心律失常
Arrhythmias
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Definition:
An arrhythmia is an abnormality of rate,
regularity, or site of origin of the cardiac
impulse or a disturbance in conduction
that causes an abnormal sequence of
activation.
Mechanisms Responsible
for Arrhythmias
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Abnormalities of impulse generation
A. Alterations of normal automaticity
B. Abnormal automaticity
C. Triggered activity
Early/Delayed afterdepolarization
Abnormalities of impulse conduction
A. Reentry: 1. Unidirectional block; 2. Anatomic or
functional reentrant circuit ; 3. wavelength
B. Conduction block
Combined abnormalities of impulse generation and
conduction
Diagnostic Approaches to
Arrhythmias
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History and physical examination
ECG
Ambulatory ECG recording: Holter recording
Excise ECG: treadmill test
Trans-esophageal electrophysiological study
Invasive electrophysiological study (EPS)
Management of Arrhythmias
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Antiarrhythmic drugs
Cardiac pacemakers
DC cardioversion/defibrillation
Implantable cardioverter/defibrillater (ICD)
Radiofrequency catheter ablation
Surgical operation
Classification of Antiarrhythmic drugs
(Vaughan-Williams)
ClassⅠ: Sodium channel blockade
Ⅰa: phase 0 depression, 2+; repolarization, +
Ⅰb: phase 0 depression, +; repolarization, Ⅰc: phase 0 depression, 3+; repolarization, ±
 Class Ⅱ: Beta-adrenergic blockade
 Class Ⅲ: Repolarization prolongation
 Class Ⅳ: Calcium channel blockade
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Atrial fibrillation:
common causes
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Coronary artery disease
Hypertensive heart disease
Valvular heart disease, mitral stenosis
Thyrotoxicosis
Atrial fibrillation:
ECG characteristics
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Absence of P waves
Very irregular baseline, f waves, with a rate
of 350-600 bpm, best seen in V1, Ⅱ
Irregular QRS complex rate, usually normal
shape
Atrial fibrillation:
auscultation features
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Variation in the intensity of S1
Extremely irregular heart rate
Pulse deficit
Atrial fibrillation: classification
and management strategies
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Paroxysmal (<24-48hr): preventing
further attacks
Persistent: attempting restoration of
sinus rhythm
Permanent: offering good control of
ventricular rate
Atrial fibrillation:
treatment
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Etiological therapy
Restoration of sinus rhythm
paroxysmal: beta-blocker, propafenone,
cedilanid, amiodarone
persistent: drugs, DC
Control on ventricular rate
digoxin, betablocker
Prevention of thromboembolism
aspirin or ticlipidine, warfarin
Paroxysmal SVT- AVNRT & AVRT
ECG features
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Sudden initiation and termination
Fixed relationship between p the wave
and QRS complex, with p often
superimposed in ORS-T
Regular rate of 150-250 bpm
Narrow QRS complexes unless there is
a aberrant ventricular conduction or
pre-existing bundle branch block
Paroxysmal SVT:
treatemnt
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Vagal maneuvers: Valsalva maneuver or
carotid sinus massage
First choice of drugs: adenosine 6-12
mg iv, or verapamil 5 mg iv
Preferred choice of drugs: propafenone
70 mg iv; cedilanid 0.4-0.6 mg iv
DC cardioversion
Radiofrequency catheter ablation
Pre-excitation syndrome
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Abnormal connection between the
atrium and the ventricle
Pre-excitation syndrome
ECG features
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Short PR interval
Slurred upstroke of QRS complexes (the
delta wave)
broad QRS complexes
Secondary ST-T abnormalities
(reflecting modified ventricular
repolarization secondary to abnormal
depolariozation
Atrial flutter:
characteristics
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Regular sawtooth like wave with a rate
of 250-350 bpm
Ventricular response may be 1:1 (300),
2:1 (150), 3:1 (100) or 4:1 (75), etc
Severity of the symptoms depends on
the ventricular rate
Causes are similar to atrial fibrillation
Premature beats
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Atrial
AV junctional
Ventricular
Clinical considerations
ECG features
Management strategies
Ventricular tachycardia
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ECG: ≥3 VPBs in succession at a rate of
100-250 bpm; suggesting VT: ventricular
captures, fusion complexes
Clinical: coronary heart disease, AMI;
signifying myocardial damage
Treatment: drugs (lidocaine amiodarone)
DC cardioversion (synchronized)
Torsades de Pointes (TDP)
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ECG: an irregular rapid ventricular
rhythm with a periodic twisting axis
seen on ECG; long QT interval
Etiology: congenital long QT syndrome;
acquired long QT syndrome, as
antiarrhythmic drugs (ClassⅠa,
ClassⅢ); hypokalamia,
hypomagnesemia
Torsades de Pointes
management
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Identifying and treating any precipitating
factors
MgSO4, IV; avoidance of drugs
lengthening APD
Atropine, isoprenaline infusion or
ventricular pacing to increase heart rate
Beat-blocker for congenital long QT
sydrome
Ventricular flutter / fibrillation
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Irregular rapid ventricular depolarization
No organized ventricular contractions, no
pulse, loss of consciousness
Most common cause: AMI, drug toxicity,
electrolyte disturbances, electric shock, end
stage of many disease processes
Management: non-synchronized DC
defibrillation, cardiopulmonary resuscitation
Sick sinus syndrome (SSS)
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Definition:characterized by intrinsic
inadequacy of sinus node pacemaking and
/or conduction failure between sinus node
and the rest of the atrium
Etiology: coronary heart disease,
degenerative process, cardiomyopathy
Clinical manifestations: insufficiency of
blood supply to important organs
Sick sinus syndrome (SSS)
ECG features
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Marked sinus bradycardia < 50 bpm
measured as SNRT, SACT and IHR
Sinus arrest / sinoatrial block
Holter recording
Bradycardia-tachycardia syndrome
atrial tachyarrhythmias
Probable coexistence with
atrioventricular block
Cardiac arrhythmias
questions?
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What are the common causes, ECG features,
auscultation characteristics and
management strategies of atrial fibrillation?
Please list the management protocols of
paroxysmal supraventricular tachycardia
Please list the concept and ECG findings of
sick sinus syndrome
Please consider the differential diagnosis of
wide QRS tachycardia