A 28-year-old woman presented to the emergency department with rapid palpitations, chest pain, and dizziness while playing cello. On examination, she had a regular pulse of 180 bpm and a blood pressure of 100/70 mm Hg with no signs of heart failure. An ECG showed a regular narrow-complex tachycardia without visible P-waves, consistent with supraventricular tachycardia.

1. Approach to a patient With Narrow QRS complex TACHYCARDIA Dr.Nagula Praveen 24-08-2011

4. STEP wise Look for QRS duration. QRS complex regular/irregular. Then look for presence of p waves. P waves morphology P waves and QRS relationship 1:1 AV block present. QRS alternation Termination initiation of tachycardia. Effect of BBB on tachycardia cycle length.

5. Decision tree schema by BAR and colleagues Ref–ncbl.org.in

8. In brief from the diagram clues Response to carotid sinus massage or adenosine –with termination of arrhythmia with Pwave –AVNRT with atrial premature beat . Tachycardia persists with AV block –AT,AFL,SANRT Pseudo r ‘ wave in V1 –AVNRT SHORT RP interval – AVNRT,AVRT Long RP interval – AT,SANRT,AVNRT atypical

10. ECG findings

11. Main Mechanisms and Typical Electrocardiographic Recordings of Supraventricular Tachycardia.

15. Differentiation of AVNRT from AVRT

17. AVNRT Presence of a narrow complex tachycardia with regular R-R intervals and no visible 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.

18. AV NODAL REENTRANT TACHYCARDIA

21. AFTER ADENOSINE

25. 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.

26. AV REENTRANT TACHYCARDIA

27. PRinterval PR interval RP interval

30. WPW syndrome Two types Orthodromic Antidromic Antidromic is wide complex tachycardia In NSR detected by delta wave. Can ppt into 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

34. Orthodromic AVRT

35. LOWN GANONG LEVINE syndrome Short PR interval Normal QRS complex PSVT

36. Sinus Tachycardia

37. Focal Atrial Tachycardia P wave morphology changes. PR interval > 0.12 sec . Second,third degree AV block can occur. Tachycardia terminates with a qrs complex .. Right atrial origin– p wave inverted in V1. If biphasic in V1—initially positive then negative. Upright in lead AVL Opposite if of left atrial origin Superior origin –upright p waves in inferior leads Inferior origin –p waves are inverted in inferior leads.

39. Focal atrial tachycardia (LA focus)

40. Multifocal Atrial Tachycardia At least three consequtive p waves with different morphologies with a rate > 100 bpm to be present. Isoelectric baseline between p waves. Also called as choaticatrial tachycardia Mostly seen in COPD ,electrolyte abn,theophylline Rate usually does not exceed 130-140 bpm.

41. Multifocal Atrial Tachycardia

42. SANRT Microreentrant tachycardia Usually precipitated and terminated by premature atrial complexes. Atrial rate is usually 120-150 bpm. IART - Large or small reentrant circuit. AV block can occur.

43. Junctionaltachycardias Non paroxysmal – accelerated junctional rhythm Rate < 100 bpm Usually junctional node 40-60 bpm Paroxysmal or focal junctional tachycardia is rare –automaticity. 110-250bpm. P waves may be before or after QRS complex Infrequent and nonsustained episodes –no treatment Acute termination of SVT and establish the mechanism of SVT in case of acute setting. Long term goal is abolishing the arryhthmia substrate. Precipitating factors – electrolyte imbalance,hypoxia,ischemia,hyperthyroidism to be sought out.

44. Acute Treatment Of SVT

45. A 12 lead ECG during tachycardia and NSR. No delay in therapy if the mechanism of SVT is not known. Perform CAROTID SINUS MASSAGE,or give 6mg bolus adenosine. In case of severe hemodynamic compromise a synchronisedcardioversion to be given.

46. Carotid sinus massage Check for carotid bruit before massage. At the level of cricoidcartilage,at the angle of mandible the carotid sinus is situated. Gentle pressure is applied over the carotid sinus for 5 -10 seconds. ECG recording to be present. In case of no response – try on the other side. Simultaneous pressure not to be applied both sides. Alternative manuevres are valsalva,gagreflex,ice water pouring over the face.

47. If SVT is suspected to be AVnode dependent – drug of choice is adenosine and CCBs verapamil and diltiazem. Useful for sustained cases of AV node independent tachycardias. But digoxin,BBs,CCBs better control of ventricular response in atrialtachycardias Class I agents to be combined with AV nodal blocking drugs – to eliminate 1:1 conduction of atrial to ventricles.

50. Pharmacologic Agents for Short-Term Treatment of Supraventricular Tachycardia (SVT). Delacrétaz E. N Engl J Med 2006;354:1039-1051.

51. AFTER ADENOSINE

52. Algorithm for Short term management of SVT

53. Algorithm for long term Management of SVT

57. But sustained.well tolerated hemodynamically.

58. Patients who have had only a single episode of SVT..

59. 100-200mg of flecainide at the onset of SVT is a reasonable approach…until he reaches the hospital.

60. 40-160 mg verapamil –without preexcitation,

61. Betablockers

62. Propafenone 150-450 mg.

65. Adenosine precipitates asthma

66. Given rapidly in 1-2 sec.

67. If given by peripheral vein uplift the arm..

68. Max dose is 30 mg

69. 6- 12-12 mg

70. Terminates AVNRT .AFL with 2:1 block

72. Usually 60 % cases respond to a dose of 6 mg and 95 % cases at 12 mg.

73. Type 1 a AAD, 1c,iii,AMIODARONE in refractory cases.

74. Beta blockers not to used IV in heart failure.

76. Catheter Ablation of Cardiac Arrhythmias.

77. Pacemakers Temporary role in case of digoxin toxicity. Permanent in case of long term control To terminate the tachycardia Revert into sinus rhythm Prevent the occurrence. Overdrive suppression RF induced atrial pacing are used No role of surgery presently in PSVT rx .

79. Some important points Rxof PSVT given for patient comfort except in IHD,MS When the QRS complex is wide and VT is mistaken as SVT with ABERRANT conduction IV verapamil – not recommended decreases BP. If DC cardioversion to be avoided because of possible adverse response to digitalis adm …pacing Rt atrium and ventricle via temp pacing. In WPW syndrome avoid VERAPAMIL,LIDOCAINE . Avoid digoxin. In SANRT ,IART –class IA,IC ,BB SANRT –digoxin.

80. Cont… Rx of ectopic atrial tachycardia – consider digitalis toxicity,chronic lung disease,metabolicabn,electrolyteabnormalities,acute MI ----temporary pacing. Unsuccessful is EC Removal or reversal of inciting factor Surgical excision of focus. Rx of MAT –chronic lung disease,metabolic,rare is digitlais toxicity ---CCBS,BBs ..no role of cardioversion,devices ,surgery.

82. 2.IV adenosine.

83. 3.long term treatment depends upon episodes.

84. 4.any underlying abnormality to be checked for.

85. 5.definitive etiology only knon by EP study.

86. 6.95% cases respond to RF ablation.

87. 7.much less complications with cryoablation.

89. SUPRAVENTRICULAR TACHYCARDIAS “You only get so many heart beats – you should save some for later in life” Dr. Samuel Levine

93. DIAGNOSIS IS ATRIAL FLUTTER

94. Sinus tachycardia was thought.. but it was AFL

96. AVNRT in structural heart disease

97. Look for the correct lead placement

98. AVNRT can occur in the background of acute MI

108. Special problems 1.Coexisting Double Tachycardias May not be identified during noninvasive testing ..needs EP study. Ex—typical AVNRT and AT. Concentric –eccentric –concentric. AVNRT –both APC,VPC AT only APC 2.Pseudo AF- infrequent presentation of PSVT. Occurs during onset and termination of tahcycardia. Multiple accessory AV pathways. In young who have AF without other risk factors. 5% of AVNRT. Group beating is seen

110. HURST’S THE HEART – 12 th edition.

111. BRAUNWALD’S HEART DISEASE –A TEXTBOOK OF CARDIOVASCULAR MEDICINE – 7 th ED

112. HARRISON’S PRINICPLES OF INTERNAL MEDICINE -17 th ED

113. SUPRAVENTRICULAR TACHYCARDIA –NEJM 2006

114. CARDIOVASCULAR MEDICINE – SVT – JERONIMO FERRE’

115. BASIC AND BEDSIDE ELECTROCARDIOGRAPHY –ROMULO.F.BALTAZAR

116. SCHAMROTH –ELECTROCARDIOGRAPHY

117. www.medscape.com

118. www.ecglibrary.com

119. www.googleimages.com

120. www.acc.org.

121. www.clinicaltrials.gov

123. Aim for any case of cardiology

124. Thank you Sagittarian