Abstract
Abstract
Background
In obstructive hypertrophic cardiomyopathy, surgical myectomy is highly effective but carries a recognized risk of postoperative conduction disturbances. Percutaneous intramyocardial septal radiofrequency ablation (Liwen procedure) is a less invasive alternative, but head-to-head comparisons of longitudinal hemodynamic trajectories and conduction system safety remain scarce, limiting evidence-based treatment selection.
Methods
This single-center retrospective cohort included 211 patients treated 2018–2023 (124 Liwen, 87 modified Morrow myectomy). The primary longitudinal analysis included 133 patients with 1-year follow-up and serial data (75 Liwen, 58 modified Morrow myectomy).
Repeated outcomes were analyzed using linear mixed-effects models and generalized estimating equations, adjusted for baseline covariates.
Results
Both procedures reduced LVOT gradient, but trajectories differed (interaction
P
=0.002). At 1 year, the covariate-adjusted mean LVOT gradient remained higher after Liwen than after myectomy (16.1 vs 1.3 mmHg,
P
P
P
=0.308). Liwen had shorter procedure duration (80 vs 185 min) and hospital stay (11 vs 16 days). Serious adverse event rates were similar (8.1% vs 9.2%) but profiles differed.
Conclusions
Modified Morrow myectomy achieved more complete LVOT gradient reduction at 1 year, whereas Liwen ablation had fewer conduction abnormalities, shorter procedure duration, and shorter hospital stay. These findings highlight a clinically relevant trade-off between more complete hemodynamic relief and lower conduction-system injury and require prospective confirmation.
Clinical Perspective
What Is New? In a single-center retrospective cohort of 133 patients with symptomatic obstructive hypertrophic cardiomyopathy, modified Morrow myectomy achieved more complete 1-year left ventricular outflow tract gradient reduction (residual gradient, 1.3 vs 16.1 mmHg), whereas Liwen ablation was associated with markedly fewer new conduction abnormalities (5% vs 62%) and no permanent pacemaker implantations.
What Are the Clinical Implications? These findings highlight distinct procedural trade-offs and support individualized treatment selection based on anatomy, baseline conduction status, procedural risk, local expertise, and patient preferences; prospective multicenter studies with concurrent enrollment are needed to confirm these comparative associations.