Isolated Subepicardial Right Ventricular Outflow Tract Scar in Athletes With Ventricular Tachycardia.
BACKGROUND
High-level endurance training has been associated with right ventricular pathological remodeling and ventricular tachycardia (VT). Although overlap with arrhythmogenic right ventricular cardiomyopathy (ARVC) has been suggested, the arrhythmogenic substrate for VTs in athletes is unknown.


OBJECTIVE
The goal of this study was to evaluate whether electroanatomic scar patterns related to sustained VT can distinguish exercise-induced arrhythmogenic remodeling from ARVC and post-inflammatory cardiomyopathies.


METHODS
In 57 consecutive patients (mean age 48 ± 16 years; 83% male) undergoing catheter ablation for scar-related right ventricular VT, 2 distinct scar distributions were identified: 1) scars involving the subtricuspid right ventricle in 46 patients (group A); and 2) scars restricted to the anterior subepicardial right ventricular outflow tract in 11 patients (group B).


RESULTS
Definite ARVC or post-inflammatory cardiomyopathy was diagnosed in 40 (87%) of 46 group A patients but was not diagnosed in any patients in group B. All group B patients underwent intensive endurance training for a median of 15 h/week (interquartile range [IQR]: 10 to 20 h/week) for a median of 13 years (IQR: 10 to 18 years). The cycle lengths of scar-related VTs were significantly faster in group B patients (257 ± 34 ms vs. 328 ± 72 ms in group A; p = 0.003). Catheter ablation resulted in complete procedural success in 10 (91%) of 11 group B patients compared with 26 (57%) of 46 group A patients (p = 0.034). During a median follow-up of 27 months (IQR: 6 to 62 months), 50% of group A patients but none of the group B patients had a VT recurrence.


CONCLUSIONS
This study describes a novel clinical entity of an isolated subepicardial right ventricular outflow tract scar serving as a substrate for fast VT in high-level endurance athletes that can be successfully treated by ablation. This scar pattern may allow distinguishing exercise-induced arrhythmogenic remodeling from ARVC and post-inflammatory cardiomyopathy.
Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.
Jeroen
J
Venlet
Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.
Sebastiaan R D
SR
Piers
Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
Jan D H
JD
Jongbloed
Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.
Alexander F A
AF
Androulakis
Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.
Yoshihisa
Y
Naruse
Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.
Dennis W
DW
den Uijl
Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.
Gijsbert F L
GF
Kapel
Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.
Marta
M
de Riva
Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands; Department of Clinical Genetics, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
J Peter
JP
van Tintelen
Department of Clinical Genetics, Leiden University Medical Center, Leiden, the Netherlands.
Daniela Q C M
DQ
Barge-Schaapveld
Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands.
Martin J
MJ
Schalij
Department of Cardiology, Leiden University Medical Center, Leiden, the Netherlands. Electronic address: k.zeppenfeld@lumc.nl.
Katja
K
Zeppenfeld
D000328:Adult; D009202:Cardiomyopathies / Q000473:pathology; D017115:Catheter Ablation; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010807:Physical Endurance / Q000502:physiology*; D013177:Sports; D017180:Tachycardia, Ventricular / Q000209:etiology*; D014694:Ventricular Outflow Obstruction / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D020257:Ventricular Remodeling / Q000502:physiology*
arrhythmia; arrhythmogenic right ventricular cardiomyopathy; clinical electrophysiology; endurance athletes