Journal Article

Relation of Strain by Feature Tracking and Clinical Outcome in Children, Adolescents, and Young Adults With Hypertrophic Cardiomyopathy

Agarwal, Prachi P., Ghadimi Mahani, Maryam, Smith, Brandon M., Lu, Jimmy C., Yu, Sunkyung, Russell, Mark W., Dorfman, Adam L.

2014

Overview

Evaluation of hypertrophic cardiomyopathy (HC) in young patients is limited by lack of age-specific norms for wall thickness on cardiovascular magnetic resonance (CMR) images. Left ventricular strain may have a role in identifying and risk stratifying patients with HC, but few data exist for strain measurement on CMR images. In 30 patients (14.1 ± 3.2 years) with clinically diagnosed HC and 24 controls (15.6 ± 2.8 years), strain (radial, longitudinal, and circumferential) was evaluated by 2 experienced readers using CMR feature tracking. In patients with HC, hypertrophied segments had decreased radial (28.0 ± 5.2% vs 58.6 ± 3.9%, p = 0.0002), circumferential (−23.7 ± 1.1% vs −28.3 ± 0.8%, p = 0.004), and longitudinal (−11.2 ± 1.2% vs −21.7 ± 0.8%, p <0.0001) strains versus control segments. Hypertrophied segments had decreased longitudinal (basal segments −12.2 ± 1.9% vs −22.6 ± 1.2%, p = 0.0002), radial (basal segments 22.7 ± 10.8% vs 78.8 ± 7.2%, p = 0.0001), and circumferential (basal segments −22.4 ± 1.7% vs −30.6 ± 1%, p = 0.0004) strains versus nonhypertrophied segments in patients with HC. Longitudinal strain had the lowest intraobserver and interobserver variabilities (coefficient of variability −15.7% and −18.5%). After a median follow-up of 28.1 months (interquartile range [IQR] 4.2 to 33.1), 7 patients with HC with an adverse event outcome (5 ventricular tachycardia, 1 appropriate implantable cardioverter-defibrillator discharge, and 1 death) had reduced global radial (median 39.7%, IQR 39.6% to 46.6% vs 65.4%, IQR 46.1% to 83.4%, p = 0.01) and longitudinal strains (median −16.5%, IQR −18.7% to −15.5% vs −19.7%, IQR −23.8% to −17.5%, p = 0.046) compared with patients with HC without an event. In conclusion, CMR feature tracking detects differences in global and segmental strains and may represent a novel method to predict clinical outcome in patients with HC. Further study is necessary to evaluate longitudinal changes in this population. •In young patients with hypertrophic cardiomyopathy, strain by feature tracking is reduced in hypertrophied segments.•Global radial and longitudinal strains are decreased in patients with hypertrophic cardiomyopathy with adverse events.•Intraobserver and interobserver variabilities are high, necessitating refinement before clinical use.

• Publisher: Elsevier Inc,Elsevier Limited
• Subject: Adolescent / Cardiology / Cardiomyopathy, Hypertrophic - diagnosis / Cardiomyopathy, Hypertrophic - genetics / Cardiomyopathy, Hypertrophic - physiopathology / Cardiovascular / Child / Clinical outcomes / Disease Progression / Echocardiography / Female / Follow-Up Studies / Genetic Testing - methods / Genotype / Heart attacks / Heart Ventricles - diagnostic imaging / Heart Ventricles - pathology / Heart Ventricles - physiopathology / Humans / Magnetic Resonance Imaging, Cine - methods / Male / Mutation / Myocardium - pathology / Phenotype / Prognosis / Retrospective Studies / ROC Curve / Stroke Volume / Ventricular Function, Left - physiology / Young Adult