Its a medical presentation describing how to approach to various cardiac arrhythmias in systematic way. Illustrated with more ECG photographs from standard sources.
1. Approach to Arrhythmias
Presenter : Dr. Mohammed Jaleel P
Moderator : Prof. Ng Taruni Devi
Regional Institute of Medical Sciences, Imphal
2. INTRODUCTION
• Arrhythmias are one of the common diseases we used to see
in daily practice
• Fatal sometimes if not treated properly or on time
• Becomes diagnostic challenge sometimes
• In addition to history and examination, ECG is more
important, particularly at the time of symptoms.
7. Focal Atrial Tachycardia
• Regular atrial tachycardia with defined P wave
• Abrupt onset and offset (diff from sinus tachy)
• AT will not terminate with AV block (from AVRT,AVNRT)
• P wave morphology tells location of focus
• Atrial septum- Narrow p wave
• Left atrium- V1 (monophasic positive), I& avL (negative)
• Superior location – inf leads (positive P)
• Inferior locations – neg p wave
8. Contd…
• Rx:
• Adenosine, Beta blockers, CCB (improve tolerance by AV block)
• Catheter ablation (recurrent symptomatic)
9. Multifocal atrial tachycardia
• At least 3 distinct P wave morphologies
• Irregular beats. Rate 100-150 beats/min,
• Clear isoelectric intervals b/w p waves(unlike AF)
• Multiple atrial foci
• In c/c pulmonary disease, a/c illness
• Treat underlying disease ± CCB (Beta blocker avoided)
14. AV re-entry tachycardia (AVRT)
• Circulating wavefront reenter atrium
via retrograde conduction through AP
• P wave always follow QRS
• Wide QRS complexes
• Morphology of P wave depending on
pathway location
15. Paroxysmal supraventricular tachycardia
(PSVT)
• Family of tachycardia including AVRT, AVNRT and atrial
tachycardia.
• Sudden run of 3 or more such beats
• 2nd to 4th decade , mostly women
• Often tolerated, sometimes – angina, pulmonary edema,
hypotension, syncope.
• Unstable- sync DC shock (rarely needed)
17. Atrial flutter
• Neg saw toothed flutter waves in II, III, avF
• Positive P waves in lead V1
• Atrial rate-- 240-300 beats/min
• Usually a/w atrial fibrillation
19. • Re-entry circuit:
• Common Afl – cavotricuspid isthmus dependent
• Atypical Afl -- not dependent
Atrial flutter and fibrillation
30. PVC which suggest structural heart disease:
• With broad notching and slurred QRS complexes
• PVC with RBBB configuration
• Multifocal PVC
Frequency and severity of arrhythmia – severity of
disease
31. Treatment
• Treatment approach to patients with PVCs depends on ± of
symptoms and ± underlying structural heart disease
• Beta blocker , CCB as the first-line drug for treatment
• Other options - antiarrhythmic medications or radiofrequency
catheter ablation
• PVCs associated LV dysfunction- Radiofrequency ablation
32. Accelerated idioventricular rhythm (AIVR)
• Repetitive ventricular rhythm occurring at a rate between 60 and
100 beats per min
• Accelerated ventricular focus that generates an impulse faster
than the sinus node and therefore assumes control
• Fusion beat at onset and termination of arrhythmia
• Common occurs;
• Reperfusion of occluded coronary artery
• Resuscitation
34. • 3 or more abnormaly shaped PVCs
• >120 msec, ST-T vector opposite the major QRS
deflection
• R-R interval regular, or vary
• Atrial activity – independent, or can be depolarized by
ventricles retrogradely (VA association)
• Rates range 100-250 bpm
• Onset : usually sudden
Ventricular tachycardia (V-tach or VT)
35. Definitions of various v-tachs
• VT: The occurrence of three or more PVC complexes (>
120ms) with a rate of > 120 bpm in succession is called as VT.
• Slow VT - HR >100 & < 120 bpm.
• Non sustained VT : Termination of VT by itself in < 30 sec.
• Sustained VT: for >30 sec. or requiring termination because of
hemodynamical collapse.
36. Contd…
• Pulseless VT – VT with hemodynamic collapse that
requires defibrillation & treated as VF.
• VT storm – repeated VT episodes requiring the DC shocks.
(≥ 3VT/24hrs)
• VF: Rate >220 bpm
39. • Concordance: Chest leads, i.e. leads V1-6 show entirely
positive (R) or entirely negative (QS) complexes, with no RS
complexes seen.
40. VT (contd…)
• Brugada’s sign– The distance from
the onset of the QRS complex to the
nadir of the S-wave is >100ms
• Josephson’s sign – Notching near the
nadir of the S-wave
• MORRISON’S Sign: complexes with
(Rr’) a taller left rabbit ear. This is the
most specific finding in favour of VT.
42. Treatment of VT
• Unstable sync DC shock
• Stable trial of adenosine (r/o SVT with aberrancy)
• IV amiodarone is DOC if heart disease present
• Evaluate for underlying heart disease
• r/c VT antiarrythmic or catheter ablation
• Sustained VT with structural heart dis ICD
45. Wolf Parkinson white syndrome
• Short P-R interval (<0.12s)
• Slurred initial portion of QRS (delta wave)
• Prolonged QRS duration
• Accessory pathway connecting
atrium and ventricle
across valve ring
• Mc- b/w left atrium and free wall
of left ventricle
49. Torsade de pointes
• Arrhythmia a/w Long QT Syndrome – Polymorphic VT called
TdP.
• The peaks of the QRS complexes appear to "twist" around the
isoelectric line of the recording,
hence the name torsade de pointes or "twisting about the
points."
51. Contd…
• Prolonged QT interval in the last sinus beat preceding the
onset of the arrhythmia, a ventricular rate of 160 to 250 bpm,
irregular RR intervals
• Torsades de pointes episodes usually are short-lived and
terminate spontaneously. Some times progress to VF
• r/c episodes – IV MgSO4 1-2g.
52. Idiopathic VT
• Idiopathic VT refers to any VT that is not associated with
structural heart disease
• Outflow tract VT - triggered automatic arrhythmias- RVOT-
LBBB
• Fascicular VT- reentrant arrhythmias within the Purkinje
system- LV- RBBB
• Treatment- beta blockers
CCB- Verapamil
• Not effective/severe symptoms --Catheter ablation
53. Ventricular fibrillation
• Most frequent mech of sudden cardiac death (SCD).
• Rapid, disorganized ventricular arrhythmia, resulting in no
uniform ventricular contraction, no cardiac output, and no
recordable blood pressure.
• The ECG in VF shows rapid (300 to 400 beats/min), irregular,
shapeless QRST undulations of variable amplitude, morphology
and interval.
• ACLS guideline with defibrillation -> sinus rhythm
• If no reversible cause identified consider ICD
58. SA node dysfunction
• Sinus pause & Sinus arrest
• Sinus pause of <3sec is common in awake athletes
• Sinus exit block
• Intermittent conduction from SA node
• Can be classified similar to AV blocks
Sick sinus syndrome (SSS)
• Dysfunction of SA node often secondary to senescence of
SAN or surrounding myocardium
61. 1st degree AV block
All P waves are conducted
• Each P followed by QRS
• PR interval is uniformly prolonged (>200 ms)
62. Second degree AV block
Intermittently droped QRS complexes
(mobitz type 1)-Wenckebach pattern
• PR interval progressively lengthens until 1P wave is not conducted
• PR interval after nonconducted beat is shorter
• Ratio of number of P wave to QRS as nomenclature
63. Contd…
Mobitz type II
• PR intervals of conducted beats are constant
• Occasional P waves without following QRS
64. 3rd degree (complete) heart block
No stimuli transmitted from atria to ventricle
• Independent atrial and ventricular activity
65. Junctional escape rhythm
• No P wave apparent
• Heart rate 40-60 beats/min
• Regular Narrow QRS complexes
66. Ventricular escape rhythm
• No P wave (rarely neg P after QRS)
• Ventricular rate <40 beats/min
• regular Wide QRS complexes
67. Atrial fibrillation with slow ventricular
response
• No P wave
• Irregular narrow QRS complexes
• Ventricular rate <60beats/min
68. Conclusion
• Arrhythmias are one of the commonly encountered problems
in clinical practice
• Cardiac arrhythmias result from abnormality of impulse
generation or conduction or both
• ECG can differentiate between most of the arrhythmias.
• Rate, QRS width, regularity of R-R interval and P wave all
are important in approaching arrhythmias.