BACKGROUND: The impact of QRS morphology and duration on the effectiveness of cardiac resynchronization therapy (CRT) has been usually assessed separately. The interaction between these 2 simple ECG parameters and their effect on CRT has not been systematically assessed in a large-scale clinical trial. METHODS AND RESULTS: The Resynchronization-Defibrillation for Ambulatory Heart Failure Trial showed that implantable cardioverter defibrillator-CRT was associated with a significant reduction in the primary end point of all-cause mortality or heart failure hospitalization. For this substudy, we excluded patients in atrial fibrillation and those with a previous pacemaker. All baseline ECGs were reviewed by a panel of 3 experienced electrocardiographers. A total of 1483 patients were included in this study. Of these, 1175 had left bundle-branch block (LBBB) and 308 had non-LBBB. In patients with LBBB receiving implantable cardioverter defibrillator-CRT, there was a reduction in the primary outcome and in each individual component of the primary outcome. Furthermore, there was continuous relationship between QRS duration and extent of benefit. In patients with non-LBBB and QRS ≥160 ms, the hazard ratio for the primary outcome was 0.52 (0.29-0.96; P=0.033); in patients with QRS <160 ms, the hazard ratio was 1.38 (0.88-2.14; P=0.155). CONCLUSIONS: In patients with LBBB, there was a continuous relationship between broader QRS and greater benefit from implantable cardioverter defibrillator-CRT. However, our data do not support the use of implantable cardioverter defibrillator-CRT in patients with non-LBBB, especially when the QRS duration is <160 ms. There may be some delayed benefit when the QRS is ≥160 ms, but this needs further investigation. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00251251.
RCT Entities:
BACKGROUND: The impact of QRS morphology and duration on the effectiveness of cardiac resynchronization therapy (CRT) has been usually assessed separately. The interaction between these 2 simple ECG parameters and their effect on CRT has not been systematically assessed in a large-scale clinical trial. METHODS AND RESULTS: The Resynchronization-Defibrillation for Ambulatory Heart Failure Trial showed that implantable cardioverter defibrillator-CRT was associated with a significant reduction in the primary end point of all-cause mortality or heart failure hospitalization. For this substudy, we excluded patients in atrial fibrillation and those with a previous pacemaker. All baseline ECGs were reviewed by a panel of 3 experienced electrocardiographers. A total of 1483 patients were included in this study. Of these, 1175 had left bundle-branch block (LBBB) and 308 had non-LBBB. In patients with LBBB receiving implantable cardioverter defibrillator-CRT, there was a reduction in the primary outcome and in each individual component of the primary outcome. Furthermore, there was continuous relationship between QRS duration and extent of benefit. In patients with non-LBBB and QRS ≥160 ms, the hazard ratio for the primary outcome was 0.52 (0.29-0.96; P=0.033); in patients with QRS <160 ms, the hazard ratio was 1.38 (0.88-2.14; P=0.155). CONCLUSIONS: In patients with LBBB, there was a continuous relationship between broader QRS and greater benefit from implantable cardioverter defibrillator-CRT. However, our data do not support the use of implantable cardioverter defibrillator-CRT in patients with non-LBBB, especially when the QRS duration is <160 ms. There may be some delayed benefit when the QRS is ≥160 ms, but this needs further investigation. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00251251.
Authors: Alexander P Benz; Mate Vamos; Julia W Erath; Peter Bogyi; Gabor Z Duray; Stefan H Hohnloser Journal: Clin Res Cardiol Date: 2018-05-24 Impact factor: 5.460
Authors: Tomasz Fabiszak; Piotr Łach; Jakub Ratajczak; Marek Koziński; Wojciech Krupa; Jacek Kubica Journal: Cardiol J Date: 2018-11-16 Impact factor: 2.737
Authors: Yitschak Biton; Jason Costa; Wojciech Zareba; Jayson R Baman; Ilan Goldenberg; Scott McNitt; Scott D Solomon; Bronislava Polonsky; Valentina Kutyifa Journal: Clin Cardiol Date: 2018-10 Impact factor: 2.882
Authors: Thomas T Poels; Patrick Houthuizen; Leen A F M Van Garsse; Jos G Maessen; Peter de Jaegere; Frits W Prinzen Journal: J Cardiovasc Transl Res Date: 2014-05-07 Impact factor: 4.132
Authors: Xiaojuan Xia; Anne-Christine Ruwald; Martin H Ruwald; Nene Ugoeke; Barbara Szepietowska; Valentina Kutyifa; Mehmet K Aktas; Poul Erik B Thomsen; Wojciech Zareba; Arthur J Moss; Jean-Philippe Couderc Journal: Ann Noninvasive Electrocardiol Date: 2016-08-30 Impact factor: 1.468
Authors: Michael E Nassif; Yuanyuan Tang; John G Cleland; William T Abraham; Cecilia Linde; Michael R Gold; James B Young; J Claude Daubert; Lou Sherfesee; Dan Schaber; Anthony S L Tang; Philip G Jones; Suzanne V Arnold; John A Spertus Journal: Circ Heart Fail Date: 2017-10 Impact factor: 8.790