Three-Dimensional Electroanatomical Voltage Mapping and Histologic Evaluation of Myocardial Substrate in Right Ventricular Outflow Tract Tachycardia

Abstract

An early/minor form of ARVC/D may mimic idiopathic RVOT tachycardia. Electroanatomical voltage mapping is able to identify RVOT tachycardia due to concealed ARVC/D by detecting RVOT electroanatomical scars that correlate with fibrofatty myocardial replacement at EMB and predispose to sudden arrhythmic death.

Imaging Study of Ventricular Scar in Arrhythmogenic Right Ventricular Cardiomyopathy

“…Technical equipment, protocols, and reference values have been reported in details elsewhere. 4,8,10 An EMB was performed in selected patients, including all those with LV DCE, for differential diagnosis with myocarditis and sarcoidosis, according to a previously reported protocol. 10,18,19 Patients were diagnosed as having ARVC regardless of the results of EVM and CMR.…”

“…8,10 In brief, a 7F Navi-Star (Biosense-Webster) catheter, with a 4-mm distal-tip electrode and a 2-mm ring electrode with an interelectrode distance of 1 mm, was introduced into the RV under fluoroscopic guidance and used as the mapping/ablation catheter. The catheter was placed at multiple sites on the endocardial surface to record bipolar electrograms from RV inflow, anterior free wall, apex, and RV outflow tract (RVOT).…”

Arrhythmogenic Cardiomyopathy

“…Moreover, one of the main clinical challenge is still differentiation of AC from idiopathic RV outflow tract VT, which is usually benign and non-familial (Table 2) [36]. EMB can be crucial both to rule out the phenocopies such as myocarditis and sarcoidosis, especially when dealing with sporadic forms, and in the setting of negative or doubtful CMR and/or electroanatomic voltage mapping [37].…”

“…The latter is an invasive electrophysiological tool that can be performed in selected patients with suspected AC, in the setting of ventricular arrhythmias of RV origin, and/or when contrast-enhanced CMR is negative or doubtful in terms of RV involvement (Fig. 5) [36,38]. The abnormal low-voltage areas found in AC patients correspond to the loss of electrically active myocardium caused by fibrofatty replacement ("electrical scars").…”

Focus-Guided Endomyocardial Byopsy in Diagnostics of Arrhythmogenic Dysplasia of the Right Ventricle in Patients Scheduled for Catheter Ablation of Ventricular Arrhythmias

“…Corrado D, et al, опубликовали исследование, пока-завшее повышение частоты выявления гистологиче-ских изменений с помощью ЭМБ при использовании трёхмерного электроанатомического картирования [9]. Все пациенты (31 обследуемый) соответствовали критериям АДПЖ по результатам неинвазивного обследования.…”