Transapical beating-heart approach is advantageous for surgical septal reduction therapy in pediatrics

Surgical septal myectomy is the gold-standard therapeutic strategy for the majority of patients with obstructive hypertrophic cardiomyopathy. However, limited data are currently available in pediatric populations, partially due to increased technical challenges in this subgroup of patients.

From December 2018 through December 2024, 63 patients with obstructive hypertrophic cardiomyopathy aged 5 to 18 years underwent conventional septal myectomy (CSM) (n = 28) or transapical beating-heart septal myectomy (TA-BSM) (n = 35). All patients had clinical and multimodality imaging evaluations before operation and at follow-up.

Two groups of patients had largely similar baseline clinical characteristics. The median age of patients was 14 years (interquartile range, 11-16 years), and 18 of them (28.6%) were female. The median preoperative left ventricular outflow tract (LVOT) gradient was 58 mm Hg (interquartile range, 32-85 mm Hg). Around 55.6% of patients had more than moderate mitral regurgitation (CSM n = 12, TA-BSM n = 23). Both approaches demonstrated equivalent efficacy for eliminating LVOT obstruction, with a median postoperative LVOT gradient of 8 and 10 mm Hg (P = .852) in the CSM and TA-BSM groups, respectively. The degree of mitral regurgitation decreased to mild or less on follow-up in 9 (75% of 12) in the CSM group, and 20 (87% of 23) in the TA-BSM group (P = .223). Compared with those in the CSM group, patients in the TA-BSM group experienced shorter durations of surgery (1.0 vs 5.5 hours; P < .001), mechanical ventilation (3.6 vs 20.5 hours; P < .001), and intensive care unit stay (23.2 vs 56.5 hours; P = .001), with less 24-hour drain outputs (100 vs 250 mL; P < .001). The median weight of resected myocardium was much greater following TA-BSM than that in the CSM group (P = .013). Two post-CSM patients received permanent pacemaker implantation due to atrioventricular block. One patient required intraoperative thoracoscopic mitral repair due to mitral chordae tendineae fracture during TA-BSM and was discharged from hospital in normal condition. No 30-day mortality or septal perforation occurred in either group of patients.

TA-BSM is a simple, safe, and effective septal reduction treatment for pediatrics with obstructive hypertrophic cardiomyopathy. Compared with CSM, reduced surgical trauma in the TA-BSM group led to quicker postoperative rehabilitation and recovery. More importantly, with real-time transesophageal echocardiographic guidance and evaluation, the TA-BSM approach can help to overcome the technical difficulties posed by a narrowed transaortic exposure in CSM in pediatric patients.