Relationship between MDCT-imaged myocardial fat and ventricular tachycardia substrate in arrhythmogenic right ventricular cardiomyopathy.
BACKGROUND
Myocardial fibrofatty infiltration is a milieu for ventricular tachycardia (VT) in arrhythmogenic right ventricular cardiomyopathy (ARVC) and can be depicted as myocardial hypodensity on contrast-enhanced multidetector computed tomography (MDCT) with high spatial and temporal resolution. This study aimed to assess the relationship between MDCT-imaged myocardial fat and VT substrate in ARVC.


METHODS AND RESULTS
We studied 16 patients with ARVC who underwent ablation and preprocedural MDCT. High-resolution imaging data were processed and registered to high-density endocardial and epicardial maps in sinus rhythm on 3-dimensional electroanatomic mapping (3D-EAM) (626±335 and 575±279 points/map, respectively). Analysis of the locations of low-voltage and fat segmentation included the following endocardial and epicardial regions: apex, mid (anterior, lateral, inferior), and basal (anterior, lateral, inferior). The location of local abnormal ventricular activities (LAVA) was compared with fat distribution. RV myocardial fat was successfully segmented and integrated with 3D-EAM in all patients. The κ agreement test demonstrated a good concordance between the epicardial low voltage and fat (κ=0.69, 95% CI 0.54 to 0.84), but fair concordance with the endocardium (κ=0.41, 95% CI 0.27 to 0.56). The majority of LAVA (520/653 [80%]) were located within the RV fat segmentation, of which 90% were not farther than 20 mm from its border. Registration of MDCT allowed direct visualization of the coronary arteries, thus avoiding coronary damage during epicardial radiofrequency delivery.


CONCLUSIONS
The integration of MDCT-imaged myocardial fat with 3D-EAM provides valuable information on the extent and localization of VT substrate and demonstrates ablation targets clustering in its border region.
['Komatsu|Yuki|Y|', 'Jadidi|Amir|A|', 'Sacher|Frederic|F|', 'Denis|Arnaud|A|', 'Daly|Matthew|M|', 'Derval|Nicolas|N|', 'Shah|Ashok|A|', 'Lehrmann|Heiko|H|', 'Park|Chan-Il|CI|', 'Weber|Reinhold|R|', 'Arentz|Thomas|T|', 'Pache|Gregor|G|', 'Sermesant|Maxime|M|', 'Ayache|Nicholas|N|', 'Relan|Jatin|J|', 'Montaudon|Michel|M|', 'Laurent|François|F|', 'Hocini|Mélèze|M|', 'Haïssaguerre|Michel|M|', 'Jaïs|Pierre|P|', 'Cochet|Hubert|H|']
D000273:Adipose Tissue D000328:Adult D019571:Arrhythmogenic Right Ventricular Dysplasia D017115:Catheter Ablation D056149:Epicardial Mapping D005260:Female D006321:Heart D006801:Humans D021621:Imaging, Three-Dimensional D008297:Male D008875:Middle Aged D061330:Multidetector Computed Tomography D009206:Myocardium D017180:Tachycardia, Ventricular D055815:Young Adult
ventricular tachycardia arrhythmogenic right ventricular cardiomyopathy ablation imaging electroanatomic mapping arrhythmia