1. Narrow complex tachycardia
Dr Julian Johny Thottian
DM Cardiology Resident
Govt. Medical College, Kozhikode

2. ANATOMY OBLIQUE VIEW OF RT ATRIUM SHOWING RE ENTRANT PATHWAY
IN ATRIAL FLUTTER
ANATOMY OF VARIOUS
ACCESSORY PATHWAYS

3. ANATOMY OF KOCH`S TRIANGLE

4. PAC AND CONDUCTION
PAC –SINGLE/REPETITIVE OR UNIFOCAL / MULTIFOCAL IN ORIGIN
FATES OF PAC DEPENDS UPON
1) Coupling interval from the last P wave ) Preceding cycle length or Heart rate.

5. BASIC UNDERSTANDING OF PAC
PANEL 1 –ROLE OF COUPLING INTERVAL
PANEL 2- ROLE PRECEDING CYCLE LENGTH

6. What`s a supraventricular tachycardia?
Heart rhythm disturbance
Initiated either in atria or ventricle
Atrial rates > 100bpm
Requires a tissue above the His bundle to perpetuate it.
NARROW COMPLEX TACHCARDIA – A TACHYCARDIA WITH QRS WIDTH <120ms

7. Characteristics Symptomatic / asymptomatic Slow/fast
Regular or irregular
Paroxysmal ,Persistent or Permanent
Generally not life threatening.
Impairs hemodynamics
Provokes hypotension, heartfailure, syncope

8. Classification AV NODE DEPENDENT AVNRT 2. AVRT ANTIDROMIC ORTHODROMIC
AV NODE INDEPENDENT
ATRIAL TACHYCARDIA
JUNCTIONAL ECTOPIC TACHYCARDIA
ATRIAL FLUTTER
ATRIAL FIBRILLATION
ATRIAL TACHYCARDIA – FOCAL, MACRO RE ENTRANT, SINOATRIAL REENTRY
ATRIAL FLUTTER- RT- CLOCKWISE , COUNTER CLOCKWISE LT- MITRAL RE ENTRY, SCAR MEDIATED,PULMONARY VEIN
ALMOST ALL IRREGULAR TACHYS ARE AV NOT INDEPENDENT

9. SINUS TACHYCARDIA SYMPATHETIC ACTIVATION
GRADUAL ACCELERATION & DECELERATION
P WAVE MORPHOLOGY SIMILAR TO SINUS RHYTHM
RARELY EXCEED 200 RATE
ADENOSINE RESPONSE- SLOW AND THEN INCREASE GRADUALLY
INAPPROPRIATE- ST ABNORMAL TO SITUATION
RATE > 200 RARELY IN CHILDREN
DIFFICULT TO DIFFERENTIATE FROM AT – TACHY WITHOUT CHANGE DAY/NIGHT,FEVER-THEN MORE LIKELY TO BE AT,AFL WITH FIXED CONDUCTION

10. ATRIAL FIBRILLATION
Atrial activity is poorly defined & ventricular response is irregularly irregular.
THEORY- Multiple wavelets, PV-automaticity, High frequency rotors, Autonomic innervation.
A regular ventricular response with A-fib usually indicates high grade or complete AV block

11. PAROXYSMAL- Recurrent episodes( 2 or more)that terminate within 7 days of onset
PERSISTENT- Episodes that last for more then 7 days or require cardioversion regardless of duration
LONG STANDING PERSISTENT AF- Continuous episodes of persistent AF for> 1yr
PERMANENT – Restoration and maintenance of sinus rhythm has failed or not attempted.
An episode---Should last for 30s - clinical AF
Fine AF- f waves <0.5mv , coarse AF –f waves >0.5mv

12. Ashman phenomenon- follows a long short sequence
 follow a short R-R interval preceded by a long R-R interval,  has a right bundle branch block morphology and represents an aberrantly conducted complex that originates above the AV node,  duration of the refractory period of the myocardium is proportional to the R-R interval of the preceding cycle , A long R-R cycle will prolong the ensuing refractory period, and if a shorter cycle follows, the beat terminating the cycle is likely to be conducted aberrantly
 Gouaux, JL; Ashman, R (Sep 1947). "Auricular fibrillation with aberration simulating ventricular paroxysmal tachycardia.". American heart journal 34 (3): 366–73

13. ATRIAL FLUTTER RENTRANT TACHY USUALLY FROM RT ATRIUM
ATRIAL RATE BPM
TYPE 1 – TERMINATED BY ATRIAL PACING, ATRIAL RATE UPTO 240
TYPE II- CANNOT BE TERMINATED BY ATRIAL PACING
ATRIAL RATE BETWEEN /MT
MC –COUNTERCLOCKWISE- SAW TOOTHED APPEARANCE IN II, III, AVF/ NO ISO ELECTRIC SEGMENT IN BETWEEN- 90%
10%- CLOCKWISE
ATYPICAL FORMS- LOWER/UPPER LOOP RE ENTRY/ FIGURE OF EIGHT RE ENTRY

15. ATRIAL TACHYCARDIA ORIGINATE- LT,RT ATRIUMS/ VENA CAVAE/PV
FOCAL-TRIGGERED/MICROREENTRANT/AUTOMATIC
P OF DIFFERENT MORPHOLOGY
PR VARIES
ATRIAL RATES BPM
1:1 CONDUCTION/AV BLOCK
ADENOSINE CAN OCCASIONALLY STOP TACHY
DIGOXIN TOXICITY- AT WITH AV BLOCK
MONOMORPHIC AT-5-10% OF ALL REGULAR SVT

17. Focal atrial tachycardia (LA focus)

18. Focal Atrial tachycardia
AUTOMATIC AT- GRADUAL ONSET(WARM UP)/OFFSET
MAY NOT START WITH PREMATURE BEAT
P WAVE DIFFERENT
CONFUSION WITH ST & ASSOC ADENOSINE INSENSITIVITY
TRIGGERED WITH ISOPROTERENOL & NOT WITH PROGRAMMED STIMULATION
RAPID STIMULATION MAY NOT INITIATE THE TACHYCARDIA
TRIGGERED AT – SUDDEN ONSET/OFFSET
ASSOC WITH RAPID PACING , DAD??
ADENOSINE TERMINATION
CATECHOLAMINE DEPENDENT
PERSISTENT TACHY- CARDIOMYOPATHY
MICRO ENTRY AT- TERMINATION WITH VERAPAMIL,INITATED AND TERMINATED BY PACING
ASSOC WITH MI,ALCOHOAL,ELECTROLYTE IMBALANCE,COPD,DIGOXIN

19. Intra Atrial re entrant tachycardia
MACRO/MICRO REENTRY- SCAR INCISIONS LIKE FONTAN
DISCRETE P WAVES AND ISO ELECTRIC BASELINE
ADENOSINE MAY TERMINATE-15% CASES

20. SANRT MICROREENTRANT TACHYCARDIA P WAVE MORPHOLOGY SIMILAR
USUALLY PRECIPITATED AND TERMINATED BY PREMATURE ATRIAL COMPLEXES.
ATRIAL RATE IS USUALLY BPM.
STOPS AND STARTS ABRUPTLY
AV BLOCK CAN OCCUR.

21. MULTIFOCAL ATRIAL TACHYCARDIA
ALSO KNOWN AS CHAOTIC ATRIAL TACHYCARDIA
ACTIVATION FROM MULTIPLE PLACES
ATLEAST 3 DIFFERENT P WAVE MORPHOLOGIES
ISOELECTRIC BASELINE BETWEEN P WAVES
ATRIAL RATE BPM
COPD,ELDERLY ,SEPSIS,HT
EXACERBATED BY THEOPHYLLINE
ALSO EXACERBATED BY HYPOXIA,HYPOKALEMIA,ACIDOSIS,CATECHOLAMINE INFUSION

22. Multifocal Atrial Tachycardia

23. AV NODAL REENTRANT TACHYCARDIA
Figure 2. Diagram of AV nodal reentrant tachycardia (AVNRT). The electrical impulse travels in a circle using extra fibers in and around the AV node.

24. AVNRT PRESENCE OF 2 PHYSIOLOGICAL/ANATOMICAL AV NODAL PATHWAYS
65% OF REGULAR SVT
ACTIVATION- VIA SLOW FIRST THEN FAST
RATES BPM
BEGINS WITH PREMATURE ATRIAL DEPOLARISATION
PSEUDO R`- V1,PSEUDO S-II III AVF
W>M MORE IN ADULTS
STOPS WITH VAGAL MANEUVRES ABRUPTLY
SLOW LONG REFRACTORY PERIOD
RARELY ASSCO WITH CONDUCTION BLOCK

25. AVNRT
NO P waves
P waves are retrograde and are inverted in leads II,III,AVF.
P waves are buried in the QRS complexes –simultaneous activation of atria and ventricles – most common presentation of AVNRT –66%.
If not synchronous –pseudo s wave in inferior leads ,pseudo r’ wave in lead V1---30% cases .
P wave may be farther away from QRS complex distorting the ST segment ---AVNRT ,mostly AVRT.

28. AFTER ADENOSINE

30. AVRT Typical – RP interval < PR interval
RP interval > 80 milli sec
Atypical –RP interval > PR interval
Concealed bypass tract – only retrograde conduction
Manifest bypass tract– both anterograde and retrograde.
Electrical alternans –the amplitude of QRS complexes varies by 5 mm alternatively.
Rate related BBB occuring and the rate of tachycardia is decreasing –then the bypass tract is on the same side of the block.

31. AV REENTRANT TACHYCARDIA
Figure 3. A diagram of AV reentrant tachycardia (AVRT). The electrical impulse travels down the AV node to the ventricles and back to the atrium via extra fibers that connect the atria and ventricles.

32. PRinterval
PR interval
RP interval

35. AVRT MACRO RE ENTRANT CIRCUIT
TYPICAL- ANTEGRADE –AV NODE RETROGRADE VIA ACCESSORY PATHWAY- ORTHODROMIC -30% REGULAR SVT
QRS ALTERNANS
CAN BE CONCEALED/MANIFEST
DELTA WAVE
STOPS WITH VAGAL MANEUVRES ABRUPTLY
CANNON WAVES MAY NOT BE PRESENT AS A& V ACTIVATION NOT SIMULTANEOUS
CONCEALED – RETROGRADE CONDUCTION ONLY IN ACCESSORY PATHWAY

36. PRE EXCITATION SYNDROMES
WPW PATTERN-MANIFEST ANTEGRADE CONDUCTION THROUGH AP-PRE EXCITE THE VENTRICLE-WPW PATTERN
ASSOC WITH PALPITATIONS –WPW SYNDROME
ORTHODROMIC SVT IS THE MOST COMMON
IN 10% ANTEGRADE CONDUCTION VIA AP

37. WPW syndrome Two types Orthodromic Antidromic
Antidromic is wide complex tachycardia
In NSR detected by delta wave.
Can ppt AF and VF on use of AV nodal blockers
MEMBRANE ACTIVE ANTIARRHTYHMIC DRUGS are safe.
CONCEALED WPW syndrome – no delta wave .less risk of AF

40. Orthodromic AVRT

41. OTHER PRE EXCITATIONS
MAHAIM- ATRIOFASCICULAR PATHWAY CONNECTS ATRIUM TO RT BUNDLE BYPASSING AV NODE
DECREMENTAL PROPERTIES
SHORT PR WITH NO MANIFEST PRE EXCITATION
LAD & LBBB- RA TO RT BUNDLE
MAHAIM CONDUCT IN ANTEROGRADE DIRECTION ONLY
DECREMENTAL- PREMATURE BEATS ASSOC WITH SLOWER CONDUCTION

42. PERMANENT JUNCTIONAL RECIPROCATING TACHYCARDIA
PJRT- PERSISTENT AVRT CONDUCTION VIA AV NODE>> POSTEROSEPTAL SLOW AP
LONG RP TACHCARDIA
P FAR AFTER QRS

43. PJRT

44. JUNCTIONAL ECTOPIC TACHYCARDIA
AUTOMATIC / TRIGGERED
ORIGINATES AROUND AV NODE
PERSISTENT RHYTHM
DOESNOT GENERALLY TERMINATE WITH ADENOSINE
CHILDREN POST CARDIAC SX, AMI, CARDIOVERSION OF AF, MYOCARDITIS ,DIGOXIN TOXICITY
SVT WITH AV DISSOCIATION

45. DIAGNOSIS ABRUPT RAPID PALPITATIONS DIZZINESS
SYNCOPE WITH VERY FAST RATE
DYSPNOEA
CHEST DISCOMFORT
RELIEF WITH VAGAL MANEUVRES
CANNON WAVES- TYPICAL AVNRT
IRREGULAR PULSE ,PULSE DEFICIT> 10 IN AF

49. ECG findings

57. 2. MODE OF INITIATION

58. MODE OF INITIATION

59. MODE OF INITIATION

60. MODE OF INITITIATION-AVRT

61. 1. Spontaneous change in cycle length 2. No definite PR jump 3
1.Spontaneous change in cycle length 2.No definite PR jump 3.Change in P wave morphology

62. 3. MODE OF TERMINATION

66. 4.MORPHOLOGY OF P WAVES
P waves in lead Avl- Positive or biphasic (negative-positive) -Right Atrial Focus (Right to left activation)
P waves in lead aVL- Negative or isoelectric: Left atrial focus
P waves in V1– Positive (Posterior to anterior/ left-to-right activation): Left atrial focus Negative or biphasic (anterior to posterior/ right-to-left activation): Right atrial focus
P waves in inferior leads– Positive (High to low activation): HRA/ High LA Negative (Low to high activation): Retrograde P in AVNRT, AVRT or AT with low atrial focus (e.g. CS/ low CT)

67. P wave morphology contd…
Counter clockwise Typical A Flutter: Positive P waves in II/III/aVF, Biphasic F wave in I, aVL, V1
Upright F wave in V6
Clockwise Flutter waves –ve in inferior leads & V6 & +ve in V1

68. 5.MORPHOLOGY OF QRS

69. 6.VARIATION IN CYCLE LENGTH
2:1 VA conduction could generate alternating ventricular volumes and produceelectrical alternans by the Brody effect.
An alternating conduction delay or block in part of the His Purkinje system or ventricular muscle could lead to an alternating pattern of electrical activation

72. 7. RESPONSE TO VALSALVA & AV BLOCKER

73. 7.EFFECT OF BBB & AVB

74. NCT DIAGNOSTIC FEATURES
AV RATIO- >1 (A>V)-AT, AFL, AVNRT(rare) A=V- AVNRT, AVRT, AT, JT <1(A<V)- AVNRT, JT , NODOFASCIULAR TACHYCARDIA Cardiac electrophysiology, Zipes 6th edition

75. THANK YOU
THANK YOU

76. REFERENCES

77. TEXT BOOKS CARDIAC ELECTROPHYSIOLOGY- ZIPES 6TH EDITION
HURST`S-THE HEART -13TH EDITION FUSTER,WALSH,HUNT,PRYSTOWSKY
BRAUNWALD`S HEART DISEASE-9TH EDITION-BONOW,MANN,ZIPES
AN ILLUSTRATED TEXT BOOK ON HEART DISEASE BY KANU CHATTERJEE
ECG TEXT BOOK –CHOU
PEARLS AND PITFALLS - MARRIOT

78. QUESTION 1 TYPICAL LONG RP TACHYCARDIA IS NOT SEEN IN PJRT AVRT
AVNRT TYPICAL
AVNRT ATYPICAL

79. QUESTION 2 QRS ALTERNANS IS NOT SEEN IN
AVRT WITH MULTIPLE ACCESSORY PATHWAYS
ATRIAL FLUTTER
AVNRT WITH MULTIPLE FAST AND SLOW PATHWAYS
AVRT WITH DUAL AV NODAL PHYSIOLOGY

80. QUESTION 3 FALSE ABOUT MAT ATRIAL RATE 110-170
PRECIPITATED BY THEOPHYLLINE
ISOELECTRIC BASELINE BETWEEN P WAVES
CINSECUTIVE THREE DIFFERENT P WAVE MORPHOLOGY

81. QUESTION 4 FALSE IS IN RIGHT ATRIAL FOCUS – LEAD AVL POSITIVE P WAVE
IN LEFT ATRIAL FOCUS – LEAD AVL NEGATIVE P WAVE
IF P IN II III AVF POSITIVE – FOCUS HRA
IF P IN VI POSITIVE- RT ATIAL FOCUS

82. QUESTION 5 PR=RP IS NOT SEEN IN ATRIAL FLUTTER WITH 2:1 BLOCK
FOCAL ATRIA TACHYCARDIA
JUNCTIONAL TACHYCARDIA
TYPICAL AVNRT

83. QUESTION 6 GRADUAL ONSET OR`WARMING UP` IS NOT SEEN IN AVRT AVNRT AT
JUNCTIONAL TACHYCARDIA

84. QUESTION 7 FALSE ABOUT MAHAIM TACHYCARDIA
PATHWAY HAS DECREMENTAL PROPERTIES
CONDUCTS BOTH ANTEROGRADE & RETROGRADE DIRECTIONS
ATRIO HISIAN PATHWAY
LBBB MORPHOLOGY FOR TACHYCARDIA

85. QUESTION 8 FALSE ABOUT AVNRT PSEUDO S- 30% PSEUDO Q- 4%
P AFTER QRS IS VERY COMMON
NO PWAVES IS SEEN IN 66% CASES

86. QUESTION 9 IRREGULAR R-R INTERVAL IS SEEN IN ALL EXCEPT AF
AFL WITH VARIABLE BLOCK
MAT
SNRT

87. QUESTION 10
FALSE ABOUT `ASHMAN PHENOMENON`
SEEN COMMONLY IN ATRIAL FIBRILLATION
RBBB MORPHOLOGY OF CONDUCTED BEAT
SEEN IN SHORT LONG SEQUENCE
DURATION OF THE REFRACTORY PERIOD OF THE MYOCARDIUM IS PROPORTIONAL TO THE R-R INTERVAL OF THE PRECEDING CYCLE