Moloy Das1, Adrian M Suszko1, Sachin Nayyar1, Karthik Viswanathan1, Danna A Spears1, George Tomlinson1, Arnold Pinter1, Eugene Crystal1, Rupin Dalvi1, Sridhar Krishnan1, Vijay S Chauhan2. 1. From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.). 2. From the Peter Munk Cardiac Center, Division of Cardiology, University Health Network, Toronto, Ontario, Canada (M.D., A.M.S., S.N., K.V., D.A.S., G.T., R.D., V.S.C.); Department of Cardiology, Freeman Hospital, Newcastle Upon Tyne, United Kingdom (M.D.); Division of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada (A.P.); Division of Cardiology, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada (E.C.); and Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada (S.K.). vijay.chauhan@uhn.ca.
Abstract
BACKGROUND: Cardiomyopathy patients are at risk of sudden death, typically from scar-related abnormalities of electrical activation that promote ventricular tachyarrhythmias. Abnormal intra-QRS peaks may provide a measure of altered activation. We hypothesized that quantification of such QRS peaks (QRSp) in high-resolution ECGs would predict arrhythmic events in implantable cardioverter-defibrillator (ICD)-eligible cardiomyopathy patients. METHODS AND RESULTS: Ninety-nine patients with ischemic or non-ischemic dilated cardiomyopathy undergoing prophylactic ICD implantation were prospectively enrolled (age 62±11 years, left ventricular ejection fraction 27±7%). High-resolution (1024 Hz) digital 12-lead ECGs were recorded during intrinsic rhythm. QRSp was quantified for each precordial lead as the total number of low-amplitude deflections that deviated from their respective naive QRS template. The primary end point of arrhythmic events was defined as appropriate ICD therapy or sustained ventricular tachyarrhythmias. After a median follow-up of 24 (15-43) months, 20 (20%) patients had arrhythmic events. Both QRSp and QRS duration were greater in those with arrhythmic events (both P<0.001) and this was consistent for QRSp for both cardiomyopathy types. In a multivariable Cox regression model that included age, left ventricular ejection fraction, QRS duration, and QRSp, only QRSp was an independent predictor of arrhythmic events (hazard ratio, 2.1; P<0.001). Receiver operating characteristic analysis revealed that a QRSp ≥2.25 identified arrhythmic events with greater sensitivity (100% versus 70%, P<0.05) and negative predictive value (100% versus 89%, P<0.05) than QRS duration ≥120 ms. CONCLUSIONS: QRSp measured from high-resolution digital 12-lead ECGs independently predicts ventricular tachyarrhythmias in ICD-eligible cardiomyopathy patients. This novel QRS morphology index has the potential to improve sudden death risk stratification and patient selection for prophylactic ICD therapy.
BACKGROUND:Cardiomyopathypatients are at risk of sudden death, typically from scar-related abnormalities of electrical activation that promote ventricular tachyarrhythmias. Abnormal intra-QRS peaks may provide a measure of altered activation. We hypothesized that quantification of such QRS peaks (QRSp) in high-resolution ECGs would predict arrhythmic events in implantable cardioverter-defibrillator (ICD)-eligible cardiomyopathypatients. METHODS AND RESULTS: Ninety-nine patients with ischemic or non-ischemicdilated cardiomyopathy undergoing prophylactic ICD implantation were prospectively enrolled (age 62±11 years, left ventricular ejection fraction 27±7%). High-resolution (1024 Hz) digital 12-lead ECGs were recorded during intrinsic rhythm. QRSp was quantified for each precordial lead as the total number of low-amplitude deflections that deviated from their respective naive QRS template. The primary end point of arrhythmic events was defined as appropriate ICD therapy or sustained ventricular tachyarrhythmias. After a median follow-up of 24 (15-43) months, 20 (20%) patients had arrhythmic events. Both QRSp and QRS duration were greater in those with arrhythmic events (both P<0.001) and this was consistent for QRSp for both cardiomyopathy types. In a multivariable Cox regression model that included age, left ventricular ejection fraction, QRS duration, and QRSp, only QRSp was an independent predictor of arrhythmic events (hazard ratio, 2.1; P<0.001). Receiver operating characteristic analysis revealed that a QRSp ≥2.25 identified arrhythmic events with greater sensitivity (100% versus 70%, P<0.05) and negative predictive value (100% versus 89%, P<0.05) than QRS duration ≥120 ms. CONCLUSIONS: QRSp measured from high-resolution digital 12-lead ECGs independently predicts ventricular tachyarrhythmias in ICD-eligible cardiomyopathypatients. This novel QRS morphology index has the potential to improve sudden death risk stratification and patient selection for prophylactic ICD therapy.
Authors: Ryan Chow; Javad Hashemi; Sami Torbey; Johnny Siu; Benedict Glover; Adrian M Baranchuk; Hoshiar Abdollah; Christopher Simpson; Selim Akl; Damian P Redfearn Journal: Ann Noninvasive Electrocardiol Date: 2019-01-28 Impact factor: 1.468
Authors: Rob W Roudijk; Laurens P Bosman; Jeroen F van der Heijden; Jacques M T de Bakker; Richard N W Hauer; J Peter van Tintelen; Folkert W Asselbergs; Anneline S J M Te Riele; Peter Loh Journal: J Clin Med Date: 2020-02-17 Impact factor: 4.241