Table 1 Mechanism of arrhythmia generation
Structural heart diseaseStructurally normal heart

  • Congenital heart disease creating re-entrant circuits

  • Congenital “electrical only” disease

    – acyanotic heart disease, eg, ASD/VSD    – dual AV nodal pathways causing AVNRT
    – cyanotic heart disease, eg, tetralogy of Fallot    – WPW/accessory pathway
    – valvular heart disease, eg, bicuspid aortic valve    – “channelopathy”

  • Acquired

  • Acquired

    – valvular heart disease 2° to rheumatic fever    – degenerative disease of conduction system
    – valvular heart disease 2° to endocarditis    – acquired long QT syndrome, eg, drugs, metabolic
    – cardiomyopathy

  • ASD, atrial septal defect; AV, atrioventricular; AVNRT, atrioventricular nodal re-entrant tachycardia; VSD, ventricular septal defect; WPW, Wolff–Parkinson–White.