Abstract 12941: Disease Progression in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy and Ventricular Tachycardia: A Longitudinal Study With Unipolar Voltage Mapping
Introduction: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is believed to result in progressive fibrofatty replacement of the RV myocardium with development of multiple ventricular tachycardia (VT) circuits. Endocardial unipolar voltage mapping has been shown to reliably identify epicardial and endocardial (epi-endo) scar in ARVC.
Hypothesis: We studied the prevalence and mechanisms of disease progression in patients with ARVC and VT through longitudinal unipolar voltage mapping studies.
Methods: Eighteen consecutive patients (age 38±14 years) who fulfilled the revised Task Force criteria for ARVC underwent two detailed sinus rhythm endocardial unipolar voltage maps (mean 348±118 points) performed a median of 36 months apart (interquartile range 21 to 36 months, minimum 9 months) as part of VT ablation procedures. Epi-endo scar was defined using established unipolar voltage cutoff (5.5 mV). The extent of RV scar and total RV volume was measured by a dedicated software. A >5% increase in RV scar area or volume over follow-up was considered significant.
Results: At baseline, all patients had evidence of epi-endo RV scar (mean 141±82 cm2; 56±27% of the RV surface area). After a mean follow-up of 49±36 months, no significant progression of unipolar voltage scar was observed (mean 159±83 cm2, P=0.14; 63±27% of the RV surface area, P=0.07). Specifically, only 3 (17%) patients presented with progression of the RV scar >5%. The RV volumes increased during follow-up (from 206±74 mL to 258±77 mL, P=0.0003), with the majority of patients (15/18, 83%) having a significant increase in the RV volume (mean increase = 38.9%). Only 3 (17%) patients had no change in both RV scar size and volume over time.
Conclusions: In patients with ARVC and VT, progressive RV dilatation is almost uniformly observed, while rapid epi-endo scar progression is rare. These findings suggest that aggressive epi-endocardial substrate ablation should provide long-term VT control, and further research is needed to identify the mechanism(s) for and to prevent ongoing RV dilatation in these patients.
Author Disclosures: P. Santangeli: None. I. Liuba: None. C. Tschabrunn: None. M. Riley: None. F. Garcia: None. R. Bala: None. M. Hutchinson: None. G. Supple: None. D. Lin: Other Research Support; Modest; Biosense Webster. Honoraria; Modest; St Jude Medical, Biosense Webster. D. Frankel: None. R. Schaller: None. D. Callans: Honoraria; Modest; Biosense Webster, Medtronic, St. Jude Medical, Biotronik. Honoraria; Significant; Boston Scientific. E. Zado: None. F. Marchlinski: None.
- © 2014 by American Heart Association, Inc.