Bifascicular block explained
Bifascicular block is characterized by right bundle branch block with left anterior fascicular block, left bundle branch block, or right bundle branch block with left posterior fascicular block on electrocardiography. Complete heart block could be the cause of syncope that is otherwise unexplained if bifascicular block is seen on electrocardiography.[1] It is estimated that less than 50% of patients with bifascicular block have high-degree atrioventricular block, although the exact incidence is unknown.[2]
The European Society of Cardiology (ESC) suggests using electrophysiology studies to look into it (EPS). When pharmacologic stress or incremental atrial pacing induces high-degree atrioventricular block, a permanent pacemaker (PPM) is recommended. If EPS is negative, long-term rhythm monitoring with an implantable loop recorder (ILR) is advised.[3]
Most commonly, it refers to a combination of right bundle branch block (RBBB) and either left anterior fascicular block (LAFB) or left posterior fascicular block (LPFB), with the former being more common.[4]
Signs and symptoms
Patients who suffer from bifascicular block are more likely to experience syncope and unexpected death.[5]
Treatment
In those with bifascicular block and no symptoms, little with respect to treatment is needed. In those with syncope, a pacemaker is recommended.[6]
See also
Further reading
- Steinberg . Jonathan S. . Pokushalov . Evgeny . Zeidan-Shwiri . Tawfiq . Crystal . Eugene . Nakamura . Kohki . Naito . Shigeto . Ávila . Pablo . Arenal . Ángel . Shah . Shivang . Jain . Sandeep . Donnellan . Eoin . Tchou . Patrick . Bifascicular block: A clinical and electrophysiologic study . American Heart Journal . Mosby . 86 . 2 . August 1, 1973 . 0002-8703 . 10.1016/0002-8703(73)90241-X . 173–181 . 4719938 . December 30, 2023 . none.
- Book: Kiehl . Erich L. . Cantillon . Daniel J. . Heidecker . Bettina . Jr . Leslie T. Cooper . Singh . Gagan D. . Rogers . Jason H. . Wilson . Ryan E. . Ziada . Khaled M. . John . Roy M. . Jr . Thomas K. Varghese . Arrhythmia Essentials . Bradyarrhythmias—Conduction System Abnormalities . Elsevier . January 1, 2017 . 28–86 . 10.1016/B978-0-323-39968-5.00002-0 . 9780323399685 . https://www.sciencedirect.com/science/article/abs/pii/B9780323399685000020 . December 30, 2023 . none.
External links
Notes and References
- Shabbir . Muhammad Asim . Shaukat . Muhammad Hamza Saad . Ehtesham . Moiz . Murawski . Shannon . Singh . Sukhraj . Alimohammad . Rizwan . Bifascicular block in unexplained syncope is underrecognized and under-evaluated: A single-center audit of ESC guidelines adherence . PLOS ONE . PLOS . 17 . 2 . 2022 . e0263727 . 35226666 . 10.1371/journal.pone.0263727 . free . 8884493 . 2022PLoSO..1763727S .
- M . Brignole . C . Menozzi . A . Moya . R . Garcia-Civera . L . Mont . M . Alvarez . F . Errazquin . J . Beiras . N . Bottoni . P . Donateo . Mechanism of syncope in patients with bundle branch block and negative electrophysiological test . Circulation . 2001 . 104 . 17 . 2045–2050 . 1524-4539 . 11673344 . 10.1161/hc4201.097837 . 8442192 . December 30, 2023 .
- M . Brignole . A . Moya . FJ . de Lange . JC . Deharo . PM . Elliott . A . Fanciulli . A . Fedorowski . R . Furlan . RA . Kenny . A . Martín . V . Probst . MJ . Reed . CP . Rice . R . Sutton . A . Ungar . JG . van Dijk . 2018 ESC Guidelines for the diagnosis and management of syncope . European Heart Journal . Eur Heart J . 39 . 21 . August 28, 2018 . 1883–1948 . 1522-9645 . 29562304 . 10.1093/eurheartj/ehy037 . free . 2262/89469 . free .
- Web site: Lesson VI — ECG Conduction Abnormalities . 2009-01-07. https://web.archive.org/web/20090116121155/http://library.med.utah.edu/kw/ecg/ecg_outline/Lesson6/index.html. 16 January 2009 . live.
- Ohara . Kuniji . Yamada . Harumoto . Jochheim . David . Mehilli . Julinda . Chandrashekhar . Y. . Narula . Jagat . Lopes . Renato D. . Fanaroff . Alexander C. . Mack . Michael J. . Svensson . Lars G. . Nietlispach . Fabian . Bertel . Osmund . Electrophysiologic evaluation of syncope in patients with bifascicular block . American Heart Journal . Mosby . 106 . 4 . October 1, 1983 . 0002-8703 . 10.1016/0002-8703(83)90089-3 . 693–697 . 6613815 . December 30, 2023.
- Epstein . Andrew E. . DiMarco . John P. . Ellenbogen . Kenneth A. . Estes . N.A. Mark . Freedman . Roger A. . Gettes . Leonard S. . Gillinov . A. Marc . Gregoratos . Gabriel . Hammill . Stephen C. . Hayes . David L. . Hlatky . Mark A. . 2008-05-27 . ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities . Circulation . 117 . 21 . e350-408 . 10.1161/circualtionaha.108.189742 . 18483207 . 0009-7322. free .
