Layer-Specific Global Longitudinal Strain Predicts Arrhythmic Risk in Arrhythmogenic Cardiomyopathy

Area of Science:

• Cardiology
• Medical Imaging
• Genetics

Background:

• Arrhythmogenic cardiomyopathy (AC) is a serious inherited heart condition leading to malignant arrhythmias and sudden cardiac death (SCD).
• Current risk stratification for AC involves electrical, genetic, and imaging data.
• Identifying early indicators of arrhythmic risk is crucial for patient management.

Purpose of the Study:

• To evaluate if myocardial deformation parameters, specifically layer-specific global longitudinal strain (GLS), can identify patients with AC at risk of major ventricular arrhythmias.
• To correlate GLS with established risk markers like non-sustained ventricular tachycardia (NSVT), late gadolinium enhancement (LGE), and genetic status.

Main Methods:

• A cohort of 45 patients with AC underwent advanced transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR).
• Layer-specific GLS was assessed using TTE 2D speckle tracking.
• Patients were grouped based on the presence of NSVT, LGE, and genetic mutations.

Main Results:

• Next-generation sequencing revealed pathogenic mutations in 86.7% of patients.
• LGE was present in 73.3% of patients, predominantly in subepicardial-to-mesocardial layers.
• Worse epicardial and mesocardial GLS values were observed in patients with NSVT and LGE. Epicardial GLS cut-offs of -15.4% and -16.1% effectively identified individuals with NSVT and LGE, respectively, independent of LVEF.

Conclusions:

• Layer-specific GLS assessment is effective in identifying high-risk arrhythmic features in AC patients, including NSVT and LGE.
• Epicardial GLS shows promise as a tool for detecting individuals at risk of SCD in AC.
• Advanced echocardiographic strain analysis offers valuable insights into AC pathophysiology and risk stratification.