Feature Tracking Global Longitudinal Strain and the Risk of Sudden Cardiac Death in Hypertrophic Cardiomyopathy: Insights from a Chinese Cohort Without Septal Reduction Therapy (RF_TH_262)

Left ventricular global longitudinal strain (LV-GLS) is increasingly acknowledged as an important predictor of adverse events in patients with diverse cardiovascular conditions. However, the prognostic value of GLS in patients with hypertrophic cardiomyopathy (HCM) remains uncertain. This study aims to evaluate the prognostic utility of LV-GLS in a long-term follow-up hypertrophic cardiomyopathy (HCM) cohort without septal reduction therapy.
 


Methods:

We retrospectively enrolled 871 consecutive patients with HCM (mean age 49±13 years, 71% men) who underwent cardiac MRI in our center between January 2010 and December 2013. All study participants never received alcohol septal ablation or surgical myectomy during follow-up. LV-GLS were derived from cine cardiac MRI by using feature tracking method. The primary endpoint was sudden cardiac death (SCD) or SCD-equivalent events. The association between LV-GLS and SCD-related endpoints was evaluated by using time-dependent receiver operating characteristic (ROC) analysis, Kaplan-Meier analysis, and multivariable competing risk regression analysis.
 


Results:

During a median follow-up of 8.8 years, SCD-related endpoint occurred in 45 HCM patients (5.2%). Patients suffering from SCD had higher European Society of Cardiology (ESC) Risk-SCD score (2.2 ± 0.6 vs. 2.6 ± 0.6, P < .001) and absolute LV-GLS (11.4 ± 3.7% vs. 9.3 ± 3.4%, P < .001). According to time-dependent analysis, 9% is an optimal cut-off value for absolute LV-GLS in predicting the primary outcome after a 10-year follow-up. On competing risk regression analysis, absolute LV-GLS ≤ 9% was associated with a higher rate of primary endpoints (subhazard ratio: 2.66 [95% confidence interval: 1.96 to 3.36]) after adjustment for known risk factors. Finally, LV-GLS provided incremental prognostic value over 2020 American College of Cardiology (ACC)/American Heart Association (AHA) risk model (log-likelihood ratios, -262.2 vs -266.2; P = .003) and 2022 ESC risk model (log-likelihood ratios, -268.4 vs -264.9; P = .009), respectively. In the subgroup with Class Ⅲ of recommendation for implantable cardioverter defibrillator, patients with absolute LV-GLS ≤ 9% showed significantly worse prognosis than those with absolute LV-GLS > 9% (p = .002 and .004 for 2020 AHA guideline and 2022 ESC guideline, respectively).
 


Conclusion:

In HCM patients without septal reduction therapy, feature tracking LV-GLS was significantly associated with a higher risk of long-term SCD, providing incremental prognostic utility over current guidelines.