Atrioventricular Reciprocating Tachycardia

Aka: Atrioventricular Reciprocating Tachycardia, Re-entrant Atrioventricular Tachycardia, AVRT, Orthodromic Atrioventricular Re-entrant Tachycardia, Orthodromic AVRT, Antidromic AVRT, Antidromic atrioventricular re-entrant tachycardia

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II. Definitions

  1. Atrioventricular Reciprocating Tachycardia (AVRT)
    1. Form of Paroxysmal Supraventricular Tachycardia (30% of cases) with an accessory pathway (outside the AV Node)

III. Epidemiology

  1. Overall, second most common cause of PSVT (30% of cases)
  2. Most common in children (represents 60% of SVT cases in first decade of life)
  3. Decreasing Prevalence with age (represents 9% of SVT cases over age 70 years)

IV. Pathophysiology

  1. Accessory pathway between the atrium and the ventricle that bypasses the AV Node
  2. Fast, accessory pathway transmission arrives before the normal AV Node stimulus
    1. Results in preexcitation of the ventricle (as seen in WPW)

V. Findings: EKG

  1. Heart Rate 160 to 240 (up to 256)
  2. Images
    1. cv_ekg_svt_avrt.png

VI. Types: General

  1. Orthodromic, narrow complex (87% of cases)
    1. Signal passes anterograde down the AV Node, through the ventricles and retrograde up the accesory path
    2. Represents up to 87% of AVRT cases
    3. Narrow Complex Tachycardia at 150 to 250 bpm
    4. RP interval is <50% of the tachycardic RR interval
    5. Retrograde P Waves appear after the QRS in I, II, III, aVF, V1 (may be obscured by T Wave)
  2. Antidromic, wide complex
    1. Signal passes retrograde up the AV Node and anterograde down the accessory path
    2. Wide Complex Tachycardia at 150 to 200 bpm
    3. RP interval is >50% of the tachycardic RR interval (<100 msec)
    4. Short PR Interval

VII. Types: Variants

  1. Wolff-Parkinson-White Syndrome (WPW Syndrome)
    1. Orthodromic variant
    2. Anterograde conduction down the accessory path reaches the ventricle before the AV Nodal signal
    3. Results in preexcitation of the ventricle, forming a slurred upstroke of the QRS (delta wave)
  2. Permanent (or persistent) Junctional Reciprocating Tachycardia
    1. Slow retrograde conduction via the accessory pathway
    2. Results in sustained Supraventricular Tachycardia
    3. Risk of Tachycardia induced Cardiomyopathy and Congestive Heart Failure

VIII. Management

  1. Catheter Ablation (preferred)
    1. First-Line Management for recurrent AVRT
  2. Medical Management (alternative)
    1. See Paroxysmal Supraventricular Tachycardia
    2. See Supraventricular Tachycardia
    3. Orthodromic AVRT
      1. Contraindications to AV Nodal and Rate Control Agents
        1. Preexcitation such as WPW Syndrome (refer for ablation)
        2. Heart Failure with Reduced Ejection Fraction (HFrEF)
      2. Medications
        1. Beta Blocker (e.g. Metoprolol)
        2. Nondihydropyridine Calcium Channel Blocker (e.g. Diltiazem)
    4. Antidromic AVRT
      1. Contraindications to Antiarrhythmic Agents
        1. Ischemic or structural heart disease
      2. Medications
        1. Propafenone
        2. Flecainide

IX. Course

  1. May degenerate into Atrial Fibrillation

X. References

  1. Joshi and Dermark (2016) Crit Dec Emerg Med 30(8):3-12
  2. Colucci (2010) Am Fam Physician 82(8): 942-52 [PubMed]
  3. Delacretaz (2006) N Engl J Med 354(10): 1039-51 [PubMed]
  4. Helton (2015) Am Fam Physician 92(9): 793-800 [PubMed]
  5. Kumar (2006) Cardiol Clin 24(3): 427-37 [PubMed]
  6. Nasir (2023) Am Fam Physician 107(6): 631-41 [PubMed]

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