Correlations between endocardial voltage mapping, diagnosis and genetic in patients with arrhythmogenic right ventricular cardiomyopathy

The relations between voltage mapping and diagnosis or genetic background of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) have not been investigated so far.

To investigate if diagnosis or genetic background were linked to voltage mapping in ARVC.

97 patients with proved or suspected ARVC undergoing 3D endocardial mapping and genetic testing have been retrospectively included. Presence, localisation and extension of low voltage areas were correlated to ARVC diagnosis and presence of a culprit mutation.

68 patients (70%) fulfilled ARVC diagnosis according to the Task Force criteria and 43 (44%) had ARVC-causal mutations. 78 (80%) presented with some bipolar or unipolar endocardial scar. 60/ 78 patients with endocardial scar (77%) fulfilled the criteria for a definitive ARVC diagnosis versus 8/19 patients without scar (42%) (p=0.003).

In the 68 patients with a definitive diagnosis of ARVC, the presence of endocardial scar was similar whether an ARVC-causal mutation was present or not (35/40 vs 25/28, p=ns). While there was slightly more infero-lateral scars in patients carrying a pathogenic genetic variant (34/40 vs 18/28, p=0.04), there was no difference for right ventricular outflow tract (24/40 vs 17/28) and apical scars (12/40 vs 11/28) or for multiple scars (26/35 vs 14/25 patients with scars). Scar extension was greater in patients with pathogenic variants (bipolar 12±10 vs 6±10%, p=0.02, and unipolar 22±13 vs 12±15%, p=0.01).

3D endocardial mapping could have an important role for refining ARVC diagnosis. Trends for larger and more infero-lateral scars were observed in mutated patients, without difference according to the mutated genes.

Type of funding sources: None.