Cardiac structural and functional profile of patients with delayed QRS transition zone and sudden cardiac death

Aapo L Aro; Derek Phan; Carmen Teodorescu; Audrey Uy-Evanado; Kyndaron Reinier; Karen Gunson; Jonathan Jui; Heikki V Huikuri; Sumeet S Chugh

doi:10.1093/europace/euw040

Cardiac structural and functional profile of patients with delayed QRS transition zone and sudden cardiac death

Europace. 2017 Apr 1;19(4):629-635. doi: 10.1093/europace/euw040.

Authors

Aapo L Aro^{1

2}, Derek Phan¹, Carmen Teodorescu¹, Audrey Uy-Evanado¹, Kyndaron Reinier¹, Karen Gunson³, Jonathan Jui³, Heikki V Huikuri⁴, Sumeet S Chugh¹

Affiliations

¹ Heart Institute, Cedars-Sinai Medical Center, Advanced Health Sciences Pavilion, Suite A3100, 127 S. San Vicente Boulevard, Los Angeles, CA 90048, USA.
² Heart and Lung Center, Helsinki University Hospital, Helsinki, Finland.
³ Oregon Health and Science University, Portland, OR, USA.
⁴ Medical Research Center Oulu, University of Oulu and Oulu University Hospital, Oulu, Finland.

PMID: 28431059
DOI: 10.1093/europace/euw040

Abstract

Aims: Delayed QRS transition zone in the precordial leads of the 12-lead electrocardiogram (ECG) has been recently associated with increased risk of sudden cardiac death (SCD), but the underlying mechanisms are unknown. We correlated echocardiographic findings with ECG and clinical characteristics to investigate how alterations in cardiac structure and function contribute to this risk marker.

Methods and results: From the ongoing population-based Oregon Sudden Unexpected Death Study (catchment population ∼1 million), SCD cases with prior ECG available (n = 627) were compared with controls (n = 801). Subjects with delayed transition at V5 or later were identified, and clinical and echocardiographic patterns associated with delayed transition were analysed. Delayed transition was present in 31% of the SCD cases and 17% of the controls. These subjects were older and more likely to have cardiovascular risk factors and history of myocardial infarction. Delayed transition was associated with increased left ventricular (LV) mass (122.7 ± 40.2 vs. 102.9 ± 33.7 g/m2; P < 0.001), larger LV diameter (53.3 ± 10.4 vs. 49.2 ± 8.0 mm; P < 0.001), and lower LV ejection fraction (LVEF) (46.4 ± 15.7 vs. 55.6 ± 12.5%; P < 0.001). In multivariate analysis, delayed transition was independently associated with myocardial infarction, reduced LVEF, and LV hypertrophy. The association between delayed transition and SCD was independent of the LVEF (OR 1.57; 95% CI 1.04-2.38; P = 0.032).

Conclusion: The underpinnings of delayed QRS transition zone extend beyond previous myocardial infarction and reduced LVEF. Since the association with sudden death is independent of these factors, this novel marker of myocardial electrical remodelling should be explored as a potential risk predictor of SCD.

Keywords: Clockwise rotation; Delayed QRS transition; Electrocardiography; Population; Sudden cardiac death.

MeSH terms

Age Distribution
Aged
Causality
Comorbidity
Death, Sudden, Cardiac / epidemiology*
Electrocardiography / methods*
Electrocardiography / statistics & numerical data
Female
Humans
Male
Myocardial Infarction / diagnosis*
Myocardial Infarction / mortality*
Oregon / epidemiology
Prevalence
Reproducibility of Results
Risk Factors
Sensitivity and Specificity
Survival Rate
Ventricular Dysfunction, Left / diagnosis*
Ventricular Dysfunction, Left / mortality*