Abstract

Aim: The association of standard 12-lead electrocardiogram (ECG) markers with benefits of the primary prophylactic implantable cardioverter-defibrillator (ICD) has not been determined in the contemporary era. We analysed traditional and novel ECG variables in a large prospective, controlled primary prophylactic ICD population to assess the predictive value of ECG in terms of ICD benefit.

Methods and results: Electrocardiograms from 1477 ICD patients and 700 control patients (EU-CERT-ICD; non-randomized, controlled, prospective multicentre study; ClinicalTrials.gov Identifier: NCT02064192), who met ICD implantation criteria but did not receive the device, were analysed. The primary outcome was all-cause mortality. In ICD patients, the co-primary outcome of first appropriate shock was used. Mean follow-up time was 2.4 ± 1.1 years to death and 2.3 ± 1.2 years to the first appropriate shock. Pathological Q waves were associated with decreased mortality in ICD patients [hazard ratio (HR) 0.54, 95% confidence interval (CI) 0.35–0.84; P < 0.01] and patients with pathological Q waves had significantly more benefit from ICD (HR 0.44, 95% CI 0.21–0.93; P = 0.03). QTc interval increase taken as a continuous variable was associated with both mortality and appropriate shock incidence, but commonly used cut-off values, were not statistically significantly associated with either of the outcomes.

Conclusion: Pathological Q waves were a strong ECG predictor of ICD benefit in primary prophylactic ICD patients. Excess mortality among Q wave patients seems to be due to arrhythmic death which can be prevented by ICD.

EU-CERT-ICD

The EU-CERT-ICD Study Investigators: Elena Arbelo, MD, Axel Bauer MD, Frieder Braunschweig MD PhD, Josep Brugada MD, PhD, David Conen MD, Iwona Cygankiewicz MD, Michael Dommasch MD, Christian Eick, MD, Panagiota Flevari MD, Tim Friede PhD, Jan Galuszka MD, Jim Hansen MD, Robert Hatala MD, Markus Harden PhD, Katerina Hnatkova PhD, Heikki V. Huikuri MD, Juhani M. Junttila, MD PhD, Stefan Kääb MD, Gabriela Kaliska MD, Jaroslaw D. Kasprzak MD, Andreas Katsimardos MD, Milan Kozak MD, Tomasz Kuczejko MD, Andrzej Lubinski MD, Jozef Martinek PhD, Béla Merkely MD, PhD, Tomáš Novotný MD, Marek Malik PhD MD, Peter Perge MD, Burkert Pieske MD, Pyotr Platonov MD PhD, Pawel Ptaczyński, MD, Dariusz Qavoq MD, L. Rotkvić, MD, Zoltan Sallo MD, Simon Schlögl MD, Georg Schmidt MD, Moritz Sinner, MD, Rajeeva Sritharan MSc, Stefan Stefanow MD, Christian Sticherling MD PhD, Jesper Hastrup Svendsen MD DMSc, Martin Svetlosak MD, Janko Szavits-Nossan MD, Milos Taborsky MD, Anton Tuinenburg, MD, Bert Vandenberk MD, Marc A. Vos PhD, Rik Willems MD PhD, Stefan N Willich MD PhD, Christian Wolpert MD, Markus Zabel MD, Ante Anic, MD, Zoran Bakotic MD, Steffen Behrens MD, Dieter Bimmel MD, Sandro Brusich MD, Rüdiger Dissmann MD, Gerian Grönefeld, MD, Przemyzlav Guzik MD, Svetoslav Iovev MD, Zrinka Jurisic MD, Thomas Klingenheben, MD, Nikola Pavlović MD, Joachim Seegers MD, Robert H.G. Schwinger MD, Tchavdar Shalganov MD, Vassil Traykov MD, Vasil Velchev MD.