Objectives:
To evaluate the efficacy and safety of endocardial radiofrequency septal reduction in the management of HOCM in children.
Method:
Retrospective analysis of patient records over a ten year period (1998-2008).
Results:
Twelve patients with median age of 10.2 years (range 4-17.2) and median weight of 31.3 kg (range 16-68.7) underwent 14 procedures. The mean (SD) peak systolic echo gradient across LVOT was 87.6(±24.1) mm Hg. A mean (SD) of 20(±9.7) lesions were applied under fluoroscopic and trans- oesophageal echo guidance using a cooled tip ablation catheter whilst monitoring the cardiac electrogram for the presence of a His bundle potential. Mean (SD) fluoroscopy time was 25.8 (±6.4) minutes. Mean (SD) post-procedure Troponin-T level was 3.6 (±2.8) mcg /l.
The mean (95% CI) decrease in the peak systolic gradient in the LVOT was 22.7(9.8 – 35.5) mm Hg in peri- procedure transcatheter measurement (p=0.002), and 51.1(36 – 66.2) mm Hg on the trans- thoracic echo performed in the follow-up out-patient visit (p<0.001). Two patients had transient heart block during the procedure and one, a groin haematoma. All but one patient reported symptomatic improvement post procedure.
Conclusion:
Endocardial radiofrequency septal reduction is an effective alternative to surgical myectomy and alcohol septal ablation in children with HOCM. It is repeatable and minimally invasive. It can result in a significant reduction in gradient but needs to be performed systematically under imaging guidance and careful monitoring with intracardiac electrograms.