Ablation of Ventricular Preexcitation to Cure Preexcitation-Induced Dilated Cardiomyopathy in Infants: Diagnosis and Outcome

Abstract

Background: To investigate the clinical features of preexcitation-induced dilated cardiomyopathy in infants and evaluate safety and efficacy of radiofrequency ablation (RFCA) in these patients. Methods: This study included 10 infants (4 males and 6 females) with mean age of 6.78±3.14 months, mean weight of 8.11±1.71 kg, and mean left ventricular ejection fraction (LVEF) was 32.6±10.34%. Tachycardiomyopathy has been excluded and all patients were refractory to the drugs. All of these 10 patients underwent RFCA. All 10 patients underwent RFCA. Results: All the accessory pathways in these patients were located on right free wall and the acute success rate was 100%. No complication associated with the procedure occurred. In one case preexcitation recurred and was ablated successfully during the second attempt. There were 3 patients with mild cardiac dysfunction (LVEF, 40≤LVEF<50%), 3 with moderate (30≤LVEF<40%), and 4 with severe cardiac dysfunction (LVEF<30%, the ages were 3, 6, 7, and 10 months, respectively). The time for LVEF normalization was 1 week, 1 to 3 months, and ≥3 months, respectively. In 3 of the 4 severe cardiac dysfunction patients, the LVEF normalized at 3, 6, and 12 months after ablation, the LVEF of the remaining case did not recover at 3 months and is still being followed. Conclusions: Ventricular preexcitation could lead to severe cardiac dysfunction during infancy. RFCA may be a safe and effective treatment option in right free wall accessory pathways, even in infants with cardiac dysfunction. Cases of more severe cardiac dysfunction might require a longer time for LVEF recovery after RFCA.

The Year in Pediatric Electrophysiology: 2023

“…Also reported was the experience of Zhang et al 7 in the treatment of ventricular pre-excitation–induced dilated cardiomyopathy in infants. Among these young patients with a mean age of 6 months and a weight of 8 kg, the mean left ventricular ejection fraction (LVEF) was 32.6%.…”

Preliminary discussions about myocardial injury and rehabilitation

“…It is easy to misdiagnose and delay the treatment of preexcitation cardiomyopathy; the disease occurs in the right-side bypass (65). The incidence of the right anterior wall bypass is the highest, and the composition is mostly in the right side wall and the right anterior wall after successful catheter ablation; the left ventricular function can be reversed and restored to normal (65). The more severe the degree of LVEF damage, the longer the time for the recovery of cardiac function (65).…”