The Many Faces of Tachycardia-Induced Cardiomyopathy (Tachycardiomyopathy)

Background: Cardiomyopathy, especially dilated cardiomyopathy is the leading reason for heart transplantation in pediatric heart failure patients. Within the realm of cardiomyopathies, tachycardia-induced cardiomyopathy (TCM) emerges as a relatively uncommon yet reversible subgroup, underscoring the importance of its identification and differentiation from other etiologies.

Methods: We conducted a comprehensive review of medical records at the Ludwig Maximilian University between January 2013 and August 2023, encompassing pediatric patients aged 0–18 years with the diagnosis of cardiomyopathy of any etiology. Furthermore, electrophysiologic studies performed in this period with concurrent catheter ablation were investigated as well. Our focus was on identifying cases characterized by heart failure and significantly impaired cardiac function concurrent with various forms of tachyarrhythmias.

Results: We identified eight cases in which tachyarrhythmias manifested with severe heart failure and clinical features of cardiomyopathy. Interestingly, at the initial clinical presentation, tachycardia was the predominant symptom in only four out of the eight cases. All cases were treated with antiarrhythmic, anticongestive and/or inotropic therapy. Electrophysiologic study was performed in 7 cases. The origin of the tachycardia was in 4 cases a focal atrial focus (focal atrial tachycardia, FAT), in one case an accessory conducting pathway leading to a permanent junctional reciprocating tachycardia (PJRT), in one case ventricular extrasystoles, and in one case a wide-QRS ventricular tachycardia, the latter two both originating from the right ventricular outflow tract. In all cases a successful catheter ablation was performed without recurrence of tachycardia. Encouragingly, all cases exhibited symptom improvement and cardiac function recovery after the successful management of the tachyarrhythmias. In one case, a mechanical Ventricular Assist Device could be explanted after resolution of the tachycardia.

Conclusion: Tachycardiomyopathy, in addition to other causes of cardiomyopathy and myocarditis, represents a noteworthy albeit infrequent differential diagnosis in pediatric heart failure patients. The treatment of tachyarrhythmias offers a curative therapeutic avenue in these cases, leading to complete regression of heart failure. It is imperative to acknowledge that both the arrhythmogenic substrate and the clinical presentation of tachycardiomyopathies can manifest diversely, making their diagnosis a complex challenge.

Publication History

Article published online:
13 February 2024