RV Tissue Heterogeneity on CT

• Published in: JACC. Clinical electrophysiology 2020-09, Vol.6 (9), p.1073-1085
• Main Authors: Venlet, Jeroen, Tao, Qian, de Graaf, Michiel A., Glashan, Claire A., de Riva Silva, Marta, van der Geest, Rob J., Scholte, Arthur J., Piers, Sebastiaan R.D., Zeppenfeld, Katja
• Format: Article
• Language: English
• Subjects: arrhythmias; arrhythmogenic right ventricular cardiomyopathy; catheter mapping and ablation; computerized tomography; electrophysiology
• ISSN: 2405-500X; 2405-5018
• DOI: 10.1016/j.jacep.2020.04.029

This study sought to evaluate whether right ventricular (RV) tissue heterogeneity on computed tomography (CT): 1) is associated with conduction delay in arrhythmogenic right ventricular cardiomyopathy (ARVC); and 2) distinguishes patients with ARVC from those with exercise-induced arrhythmogenic remodeling (EIAR) and control individuals. ARVC is characterized by fibrofatty replacement, related to conduction delay and ventricular tachycardias. Distinguishing ARVC from acquired, EIAR is challenging. Patients with ARVC or EIAR and combined endocardial-epicardial electroanatomic voltage mapping for VT ablation with CT integration were enrolled. Patients without structural heart disease served as control individuals. Tissue heterogeneity on CT (CT heterogeneity) was automatically quantified within the 2-mm subepicardium of the entire RV free wall at normal sites and low voltage sites harboring late potentials (LP+) in ARVC/EIAR. Seventeen patients with ARVC (15 males; age: 50 ± 17 years), 9 patients with EIAR (7 males; age: 45 ± 14 years) and 17 control individuals (14 males; age: 50 ± 15 years) were enrolled. Of 5,215 ARVC mapping points, 560 (11%) showed LP+. CT heterogeneity was higher at sites with LP+ compared to normal sites (median: 31 HU/mm; IQR: 23 to 46 HU/mm vs. median: 16 HU/mm; IQR: 13 to 21 HU/mm; p