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Published on: December 11, 2017
Maskerading Bundle Branch Block Versus Standard Bifascicular Block: A Prognostic Analysis Results Through
Afonso Luiz Tavares de Albuquerque1, Caroline de Paula Coutinho Vaz de Lira1, José Nilo de Carvalho Neto1
1Division of Cardiology, Pronto Socorro Cardiológico de Pernambuco Prof. Luiz Tavares (PROCAPE), Universidade de Pernambuco (UPE), Recife, Brazil.
Background:
Maskerading bundle branch block (MBBB) is a rare variant of standard bifascicular bundle branch block (SBBB), associated with poor prognosis and a higher need for pacemaker implantation. Most available data are limited to case reports and reviews.
Methods:
In this prospective cross-sectional study, we evaluated 27 patients with MBBB (Group I) and 18 with SBBB (Group II), all undergoing echocardiography, 24-h Holter monitoring, and invasive electrophysiological study (EPS) after recruitment.
Results:
Group I patients had worse functional status (NYHA III-IV), larger ventricular diameters, and lower ejection fraction. The HV interval was significantly longer in Group I (66.3 ± 18.3 vs. 52.9 ± 8.1 ms; p = 0.006). Pacemaker implantation was required in 48% of Group I patients versus none in Group II (p = 0.001). Persistent atrial fibrillation was also more frequent in Group I (39.5% vs. 16.6%; p = 0.018).
Conclusion:
MBBB is associated with more severe myocardial and conduction system impairment compared to SBBB, supporting its role as a marker of worse prognosis.
