Liwen Ablation versus Modified Morrow Myectomy for Obstructive Hypertrophic Cardiomyopathy: 1-Year Hemodynamic and Conduction Outcomes
- 1Wuhan Asia Heart Hospital
Abstract
BackgroundIn 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.
MethodsThis 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.
ResultsBoth 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<0.001). However, the adjusted 1-year predicted probability of new conduction abnormalities was markedly lower after Liwen (5% vs 62%, P<0.001), with no permanent pacemaker implantations in the Liwen group. Most patients achieved gradient <30 mmHg in both groups (82% vs 96%; nominal 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.
ConclusionsModified 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 PerspectiveWhat 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.
Related
- Percutaneous endomyocardial ablation as a septal reduction strategy in symptomatic obstructive hypertrophic cardiomyopathy: A 20-year single-center observational experience.
- Hypertrophic obstructive cardiomyopathy complicated by severe midventricular obstruction treated with percutaneous transluminal septal myocardial ablation using simultaneous contrast imaging with left ventriculography and coronary angiography: a case report
- Life-long management of atrial fibrillation in a patient with hypertrophic obstructive cardiomyopathy following alcohol septal ablation: A10-year follow-up case report
- Myocardial bridge impacts septal radiofrequency ablation safety in hypertrophic obstructive cardiomyopathy
- Improvement in mitral regurgitation after alcohol septal ablation in hypertrophic obstructive cardiomyopathy: a retrospective cohort study
BibTeX
@misc{jiao2026liwen,
title = {{Liwen Ablation versus Modified Morrow Myectomy for Obstructive Hypertrophic Cardiomyopathy: 1-Year Hemodynamic and Conduction Outcomes}},
author = {J. Jiao and Y. Long and Z. Yu and Q. Fan and R. Zhou and M. Liu},
howpublished = {medRxiv},
year = {2026},
month = sep,
doi = {10.64898/2026.09.15.26363181},
url = {https://www.medrxiv.org/content/10.64898/2026.09.15.26363181v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - Liwen Ablation versus Modified Morrow Myectomy for Obstructive Hypertrophic Cardiomyopathy: 1-Year Hemodynamic and Conduction Outcomes
AU - J. Jiao
AU - Y. Long
AU - Z. Yu
AU - Q. Fan
AU - R. Zhou
AU - M. Liu
PY - 2026
DA - 2026/09/15
PB - medRxiv
DO - 10.64898/2026.09.15.26363181
UR - https://www.medrxiv.org/content/10.64898/2026.09.15.26363181v1
AB - BackgroundIn 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. MethodsThis 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. ResultsBoth 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<0.001). However, the adjusted 1-year predicted probability of new conduction abnormalities was markedly lower after Liwen (5% vs 62%, P<0.001), with no permanent pacemaker implantations in the Liwen group. Most patients achieved gradient <30 mmHg in both groups (82% vs 96%; nominal 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. ConclusionsModified 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 PerspectiveWhat 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.
ER -