Author + information
- Received May 16, 2018
- Revision received September 7, 2018
- Accepted September 20, 2018
- Published online February 18, 2019.
- Ivo Roca-Luque, MD, PhDa,∗ (, )
- Jaume Francisco-Pasqual, MDa,
- Gerard Oristrell, MDb,
- Julián Rodríguez-García, MDa,
- Alba Santos-Ortega, MDa,
- Gabriel Martin-Sanchez, MDa,
- Nuria Rivas-Gandara, MD, PhDa,
- Jordi Perez-Rodon, MD, PhDa,
- Ignacio Ferreira-Gonzalez, MD, PhDc,
- David García-Dorado, MD, PhDb and
- Angel Moya-Mitjans, MD, PhDa
- aArrhythmia Unit, Cardiology Department, Hospital Universitari Vall d’Hebron, Barcelona, Spain
- bCardiology Department, Hospital Universitari Vall d’Hebron, Barcelona, Spain
- cCardiovascular Epidemiology Unit, Cardiology Department, Hospital Universitari Vall d’Hebron, Barcelona, Spain
- ↵∗Address for correspondence:
Dr. Ivo Roca-Luque, Unitat d’ Arítmies, Servei de Cardiologia, Hospital Universitari Vall d’ Hebron, Passeig Vall d’ Hebron 119-129, 08035 Barcelona, Spain.
Objectives This study sought to compare the differences between procainamide and flecainide to stress the His-Purkinje system during electrophysiological study (EPS) in patients with syncope and bundle branch block (BBB).
Background Patients with syncope and BBB are at risk of developing atrioventricular block. EPS is recommended including class I drug challenge to unmask His-Purkinje disease in cases with baseline normal His-ventricular interval. There is little data on differences between different class I drugs.
Methods This was a prospective study of all consecutive patients undergoing EPS for syncope and BBB at a single center (January 1, 2012 to June 30, 2017). Of those patients with negative baseline EPS, 2 cohorts were compared: group A (historical cohort: procainamide) and group B (flecainide).
Results During the study, 271 patients (age 73.9 ± 12.1 years, 64.9% male, QRS duration: 139.4 ± 13.9 ms) underwent EPS. In 166, baseline EPS was negative and class I drug challenge was performed (90 procainamide, 76 flecainide). The final value and percentage increase in the His-ventricular interval (76 ± 16 ms vs. 64 ± 10 ms and 22.5 ± 6.2% vs. 11.8 ± 5.3%; p < 0.001) and diagnostic yield (14.5% vs. 7.8%, p = 0.04) were higher with flecainide. No differences were found in baseline characteristics. During follow-up (25.8 ± 6.3 months), 39 patients (24.8%) with negative EPS (19.2% with flecainide vs. 30.1% with procainamide: relative risk: 5.1; 95% confidence interval: 2.6 to 10.2; p < 0. 001) received a pacemaker.
Conclusions Flecainide has a higher diagnostic yield than does procainamide in patients with BBB, syncope, and negative baseline EPS due to a greater increase of the His-ventricular interval. Additionally, there is a lesser need for pacemaker implantation in patients in whom the class I drug test using flecainide was negative.
This work was partially supported by the Instituto de Salud Carlos III—Centro de Investigación Biomédica En Red- Cardio Vascular (CIBER-CV) Fondos Fondo Europeo de Desarrollo Regional (FEDER). The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
All authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the JACC: Clinical Electrophysiology author instructions page.
- Received May 16, 2018.
- Revision received September 7, 2018.
- Accepted September 20, 2018.
- 2019 American College of Cardiology Foundation
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