[The predictive value of left ventricular strain on cardiac magnetic resonance for adverse events in children and adolescent patients with hypertrophic cardiomyopathy].

Objective

To investigate the role of left ventricular global longitudinal strain (GLS) derived from cardiac magnetic resonance (CMR) feature-tracking in evaluating left ventricular systolic function in children and adolescents with primary hypertrophic cardiomyopathy (HCM), as well as its prognostic value for adverse cardiovascular events and heart failure-related events.

Methods

This was a single-center retrospective cohort study. Patients with primary HCM aged ≤21 years who underwent standard CMR examination at Fuwai Hospital, Chinese Academy of Medical Sciences, between January 2010 and December 2018 were included. Baseline clinical and CMR data were collected, and follow-up was completed. The primary endpoint was composite adverse cardiovascular events, and the secondary endpoint was heart failure-related events. Patients were divided into the event group and the non-event group according to whether the primary endpoint occurred. Multivariate Cox proportional-hazards regression models were used to identify independent factors associated with composite adverse cardiovascular events and heart failure-related events. Using the cohort median left ventricular GLS of -9.2% as the cut-off value, patients were stratified into the preserved GLS group (≤-9.2%) and the impaired GLS group (>-9.2%). Kaplan-Meier survival curves were plotted, and the log-rank test was performed to compare survival differences between groups.

Results

A total of 249 children and adolescents with HCM were included, aged (14.81±3.71)years, of whom 163 were males (65.5%). The follow-up duration was (66.59±33.00)months. Composite endpoint events occurred in 37 patients, including 17 heart failure-related events and 20 sudden cardiac death events; 212 patients remained event-free. After adjusting for confounders such as left ventricular ejection fraction and history of unexplained syncope, multivariate Cox regression demonstrated that the percentage of late gadolinium enhancement (LGE) and left ventricular GLS were independently associated with composite adverse cardiovascular events (left ventricular GLS: HR=1.18, 95%CI 1.04-1.35, P=0.014; LGE extent: HR=1.12, 95%CI 1.06-1.18,P<0.001) and heart failure-related events (left ventricular GLS: HR=1.52, 95%CI 1.18-1.96, P=0.001; LGE extent: HR=1.14, 95%CI 1.04-1.24, P=0.003). Kaplan-Meier analysis revealed that patients with impaired left ventricular GLS had lower cumulative event-free survival for both composite adverse cardiovascular events and heart failure-related events compared with those with preserved GLS (log-rank all P<0.001).

Conclusions

CMR feature-tracking can effectively assess left ventricular systolic function in children and adolescents with primary HCM. Left ventricular GLS and LGE percentage are independently associated with the risk of adverse cardiovascular events and heart failure-related events in this patient population.