Tachycardia Induced Cardiomyopathy

Raja Selvaraj, JIPMER

What are we doing to discuss?

  • What is TIC and what is the mechanism?
  • Common causes
  • Management
  • PVC mediated cardiomyopathy
  • Atrial fibrillation

What is Tachycardia induced Cardiomyopathy

  • Heart failure
  • Systolic dysfunction
  • ? Diastolic dysfunction
  • Due to prolonged elevated heart rate (> 100)
  • Reversible on control of arrhythmia

What are the usual causes

  • SVT
    • Focal AT / A flutter
    • AVNRT / AVRT / PJRT
  • VT
    • RVOT VT
    • ILVT
  • Misc
    • AF
    • PVCs

Mechanisms

  • Myocardial energy depletion
  • Myocardial ischemia
  • Abnormal calcium handling
  • Cellular and extracellular matrix remodeling

Sequence of events

dilated_heart.png

  • Cardiac dilatation, MR
  • Elevated filling pressures
  • wall thinning, decreased contractility
  • heart failure, neurohormonal activation

Clinical features

  • Any age (hydrops due to flutter)
  • Obvious in many patients
  • May need a high index of suspicion in some
  • Diagnosis may be confirmed only after reversal of LV dysfunction

Diagnosis

  • May be easy
    • Atrial flutter, 2:1 conduction, LV dysfunction
    • PJRT with LV dysfunction
  • May be uncertain
    • Atrial fibrillation with heart failure
    • Post MI, LV dysfunction with PVCs
  • Benefit of doubt

Management

  • SVT - ablation
  • Idiopathic VT - ablation
  • AF - rate control / rhythm control
  • Initial improvement seen as early as 24 hours
  • Most recovery within one month
  • Near normalisation in one year

PVCs

  • Repetitive dyssynchronous activation and not true tachycardia
  • Only small fraction develop cardiomyopathy
    • Related to burden / frequency, but no clear cut-off (10000, 20000, 16%, 20%, 24%)
    • PVC QRS duration > 140 ms / 150 ms
    • PVC coupling interval < 600 ms
    • Interpolation

PVC burden

pvc_burden.png

  1. Niwano et al. Prognostic significance of frequent premature ventricular contractions originating from the ventricular outflow tract in patients with normal left ventricular function. Heart 2009;95:1230-1237.
  2. Baman et al. Relationship between burden of premature ventricular complexes and left ventricular function. Heart Rhythm. 2010 Jul;7(7):865-9.

AF - an underrecognised cause ?

  • Arrhythmia in first reported case in 1913
  • Heart failure / LV dysfunction often attributed to other causes
  • Irregularity of response may contribute ?

DCM with arrhythmia or arrhythmia with TIC

  • LV dimension may help differentiate
  • BNP / LVEF not different, but LV size smaller (1)
  • LVEDD < 66 predicts TIC (2)
  1. Fujino et al. Characteristics of congestive heart failure accompanied by atrial fibrillation with special reference to tachycardia-induced cardiomyopathy. Circ J. 2007 Jun;71(6):936-40.
  2. Jeong YH et al. Diagnostic approach and treatment strategy in tachycardia-induced cardiomyopathy. Clin Cardiol. 2008;31:172–178

PVI or Ablate and PACE

  • Atypical flutter / AF - Often refractory to pharmacologic therapy
  • AVN ablation with pacing can be an excellent alternative
  • In an experienced center, PVI may be superior ?
  • Recurrences can result in rapid deterioration

PABA-CHF study

paba_chf.jpg

Khan MN et al. Pulmonary-Vein Isolation for Atrial Fibrillation in Patients with Heart Failure. N Engl J Med 2008; 359:1778-1785

Ablate and Pace

avn_ablation_metaanalysis.jpg

Wood et al. Clinical outcomes after ablation and pacing therapy for atrial fibrillation : a meta-analysis. Circulation. 2000 Mar 14;101(10):1138-44.

Points to Ponder

  • Component of TIC in post MI PVCs (1)
  • Easier to ablate (2)
  • MR sensitive marker of improvement
  • Risk of sudden death (3) - role for vest?
  • Late deaths
  1. Ablation of frequent PVC in patients meeting criteria for primary prevention ICD implant: Safety of withholding the implant. Heart Rhythm 2015;12:2434–2442
  2. Primary Radiofrequency Ablation for Incessant Idiopathic Ventricular Tachycardia. PACE 2002;25:1555
  3. Heart Failure and Sudden Death in Patients With Tachycardia-Induced Cardiomyopathy and Recurrent Tachycardia. Circulation. 2004;110:247-252