Lior Yankelson1, Aviram Hochstadt2, Ben Sadeh2, Benley Pick2, Ariel Finkelstein2, Raphael Rosso2, Sami Viskin2. 1. Cardiac Electrophysiology, Division of Cardiology, NYU Langone Health, New York University School of Medicine, New York, USA. Electronic address: lior.jankelson@nyumc.org. 2. Department of Cardiology, Tel Aviv Sourasky Medical Center, Sackler School of Medicine, Tel Aviv University, Israel.
Abstract
OBJECTIVES: To predict the QT interval in the presence of normal QRS for patients with left bundle branch block (LBBB). BACKGROUND: There is no acceptable method for simple and reliable QT correction for patients with bundle branch block (BBB). METHODS: We measured the QT interval in patients with new onset LBBB who had a recent electrocardiogram with narrow QRS for comparison. 48 patients who developed in-hospital LBBB were studied. Patients who had similar heart rate before and after LBBB were included. We used linear regression, the Bogossian method, and our new fixed QRS replacement method to evaluate the most reliable correction method. RESULTS: JTc (QTc-QRS) interval was preserved before and after LBBB (328.9 ± 25.4 ms before LBBB vs. 327.3 ms post LBBB (p = 0.550). Mean predicted preLBBB QTc difference was 1.3 ms, -21.3 ms and 1.6 ms for the three methods respectively (p < 0.001 for Bogossian comparison with the other methods). Coefficients of correlation (R) between actual preLBBB QTc with predicted preLBBB QTc were 0.707, 0.683 and 0.665 respectively (p > 0.3 for R comparisons between all methods). The average absolute difference in preLBBB QTc was 15.5 ms and 16.7 ms for the regression and fixed-gender methods (p value between the two = 0.321) and 25.5 ms for the Bogossian method, which was found to be significantly underperforming. CONCLUSIONS: In patients with LBBB, replacing of the QRS duration after deriving the QTc interval with a fixed value of 88 ms for female and 95 ms for male provides a simple and reliable method for predicting the QTc before the development of LBBB.
OBJECTIVES: To predict the QT interval in the presence of normal QRS for patients with left bundle branch block (LBBB). BACKGROUND: There is no acceptable method for simple and reliable QT correction for patients with bundle branch block (BBB). METHODS: We measured the QT interval in patients with new onset LBBB who had a recent electrocardiogram with narrow QRS for comparison. 48 patients who developed in-hospital LBBB were studied. Patients who had similar heart rate before and after LBBB were included. We used linear regression, the Bogossian method, and our new fixed QRS replacement method to evaluate the most reliable correction method. RESULTS: JTc (QTc-QRS) interval was preserved before and after LBBB (328.9 ± 25.4 ms before LBBB vs. 327.3 ms post LBBB (p = 0.550). Mean predicted preLBBB QTc difference was 1.3 ms, -21.3 ms and 1.6 ms for the three methods respectively (p < 0.001 for Bogossian comparison with the other methods). Coefficients of correlation (R) between actual preLBBB QTc with predicted preLBBB QTc were 0.707, 0.683 and 0.665 respectively (p > 0.3 for R comparisons between all methods). The average absolute difference in preLBBB QTc was 15.5 ms and 16.7 ms for the regression and fixed-gender methods (p value between the two = 0.321) and 25.5 ms for the Bogossian method, which was found to be significantly underperforming. CONCLUSIONS: In patients with LBBB, replacing of the QRS duration after deriving the QTc interval with a fixed value of 88 ms for female and 95 ms for male provides a simple and reliable method for predicting the QTc before the development of LBBB.
Authors: M Bianco; C A Biolè; S Campagnuolo; F Pietrangiolillo; A Spirito; A Galluzzo; I Nuñez-Gil; P Destefanis; A Luciano; P Carvalho; G P Varalda; A Previti; M Gravellone; A Travieso Gonzalez; F Ugo; G Pivano; F Rametta; A Perboni; R Pozzi; L Montagna; E Cerrato Journal: Int J Cardiol Heart Vasc Date: 2020-09-11
Authors: Santiago Colunga; Remigio Padrón; Daniel García-Iglesias; José Manuel Rubín; Diego Pérez; Raquel Del Valle; Pablo Avanzas; César Morís; David Calvo Journal: J Clin Med Date: 2019-09-09 Impact factor: 4.241