High rate of subcutaneous implantable cardioverter-defibrillator sensing screening failure in patients with Brugada syndrome: a comparison with other inherited primary arrhythmia syndromes.
Subcutaneous implantable cardioverter-defibrillator (S-ICD) can avoid important complications associated with transvenous leads in patients with inherited primary arrhythmia syndromes, who do not need pacing therapy. Few data are available on the percentage of patients with inherited arrhythmia syndromes eligible for S-ICD implantation. Aim of this study was to analyse the eligibility for S-ICD in a series of patients with Brugada syndrome (BrS), and to compare it with patients with other channelopathies.



Patients presenting with BrS, long-QT syndrome (LQTS), early repolarization syndrome (ERS), and idiopathic ventricular fibrillation (IVF) were considered eligible for this study. ECG screening was performed by analysis of QRS complex and T wave morphology recorded in standing and supine position. Eligibility was defined when ≥1 sense vector was acceptable in both supine and standing position. A total of 100 patients (72 males; mean age: 46 ± 17 years) underwent S-ICD sensing screening. Sixty-one patients presented with BrS, 21 with LQTS, 14 with IVF, and 4 with ERS. Thirty-four patients with BrS (56%) presented with spontaneous type 1 ECG. In the other 27 patients (44%), type 1 ECG was unmasked by ajmaline. Overall, rate of screening failure was 13%. Patients with BrS had a higher rate of inappropriate morphology analysis as compared with other channelopathies (18% vs. 5%, P = 0.07) and had a lower number of suitable sensing vectors (49.6% vs. 84.7% vs. P < 0.001). Ajmaline challenge unmasked sensing failure in 14.8% of drug-induced BrS patients previously considered eligible. In all patients, the reason for sensing inappropriateness was due to the presence of high T wave voltages.



S-ICD screening failure occurs in up to 13% of patients with inherited primary arrhythmia syndromes. Patients with BrS present a higher rate of screening failure as compared with other cardiac channelopathies.
Division of Cardiology, Electrophysiology Unit, Fondazione Cardiocentro Ticino, via tesserete 48, Lugano, Switzerland.
Giulio
G
Conte
Heart Rhythm Centre, Tokyo Medical and Dental University, Tokyo, Japan.
Mihoko
M
Kawabata
Heart Rhythm Management Centre, UZ-VUB, Brussels, Belgium.
Carlo
C
de Asmundis
Department of Molecular Medicine, University of Pavia and Department of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
Erika
E
Taravelli
Division of Cardiology, Electrophysiology Unit, Fondazione Cardiocentro Ticino, via tesserete 48, Lugano, Switzerland.
Francesco
F
Petracca
Heart Rhythm Management Centre, UZ-VUB, Brussels, Belgium.
Diego
D
Ruggiero
Division of Cardiology, Electrophysiology Unit, Fondazione Cardiocentro Ticino, via tesserete 48, Lugano, Switzerland.
Maria Luce
ML
Caputo
Division of Cardiology, Electrophysiology Unit, Fondazione Cardiocentro Ticino, via tesserete 48, Lugano, Switzerland.
François
F
Regoli
Heart Rhythm Management Centre, UZ-VUB, Brussels, Belgium.
Gian-Battista
GB
Chierchia
Division of Cardiology, Electrophysiology Unit, Fondazione Cardiocentro Ticino, via tesserete 48, Lugano, Switzerland.
Alessandra
A
Chiodini
Division of Cardiology, Electrophysiology Unit, Fondazione Cardiocentro Ticino, via tesserete 48, Lugano, Switzerland.
Alessandro
A
Del Bufalo
Division of Cardiology, Electrophysiology Unit, Fondazione Cardiocentro Ticino, via tesserete 48, Lugano, Switzerland.
Tiziano
T
Moccetti
Heart Rhythm Centre, Tokyo Medical and Dental University, Tokyo, Japan.
Masahiko
M
Goya
Heart Rhythm Centre, Tokyo Medical and Dental University, Tokyo, Japan.
Kenzo
K
Hirao
Department of Molecular Medicine, University of Pavia and Department of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
Alessandro
A
Vicentini
Department of Molecular Medicine, University of Pavia and Department of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
Gaetano M
GM
De Ferrari
Heart Rhythm Management Centre, UZ-VUB, Brussels, Belgium.
Pedro
P
Brugada
Division of Cardiology, Electrophysiology Unit, Fondazione Cardiocentro Ticino, via tesserete 48, Lugano, Switzerland.
Angelo
A
Auricchio
D000328:Adult; D053840:Brugada Syndrome / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology / Q000601:surgery*; D000066491:Clinical Decision-Making; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000295:instrumentation*; D004562:Electrocardiography; D004608:Eligibility Determination; D005060:Europe; D005260:Female; D020022:Genetic Predisposition to Disease; D040941:Heredity; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D010641:Phenotype; D011237:Predictive Value of Tests; D014041:Tokyo; D014672:Vectorcardiography