Tachycardia induced cardiomyopathy
Tachycardia induced cardiomyopathy (TIC) (or tachycardiomyopathy) is considered a reversible form of acquired cardiomyopathy where there is impaired left ventricular systolic dysfunction precipitated by a tachycardia or a tachyarrhythmia.
Typically there is an impairment left ventricular systolic function measured by an impairment left ventricular ejection fraction (LVEF) precipitated in a context of a tachycardia or tachyarrhythmia. The LVEF would return to normal limits upon restoration of normal sinus rhythm.
Epidemiology
In adults, the most common etiologic arrhythmias are supraventricular in origin. It has occurred in all age groups, from neonates to adults, with patient risk based on the rhythm present; incessant atrial tachycardia (ectopic/focal) may induce TIC in up to 28% of patients. Commonly associated rhythms in adults causing TIC include :
- atrial fibrillation
- atrial flutter
- atrial tachycardia
- re-entrant supraventricular tachycardias (SVTs)
- junctional reciprocating tachycardia
- less commonly AVNRT/AVRT (usually paroxysmal)
Ectopic atrial tachycardias are the most common etiological factor in pediatric cases. Idiopathic ventricular tachycardia, as well as frequent ventricular ectopic beats, may rarely cause TIC.
Prognosis
Usually there is marked improvement in systolic function after normalization of heart rate. The disturbances in vascular resistance, cardiac output, and ventricular filling pressures are usually reversible over the course of weeks; ventricular volumes, however, may remain persistently elevated for longer periods of time.
History and etymology
It is thought to have been first described by G H Whipple in 1967.
See also
