QT interval,general mortality and the role of echocardiographic parameters of left ventricular hypertrophy: Results from the prospective,population-based CARLA study

Abstract

Background

There is convincing evidence of an association between the QT interval on electrocardiograms and general mortality. However, results are inconclusive regarding the extent to which this association depends on ventricular mass and size.

Methods

Data were obtained from the prospective, population-based CARLA study, with a mean follow-up of 8.8 years, after exclusion of subjects with atrial fibrillation (919 men, 797 women aged 45–83 years remained eligible). Echocardiographic parameters were left ventricular mass index, left ventricular diastolic dimension index, diastolic interventricular septum thickness, diastolic left ventricular posterior wall and the relative left ventricular wall thickness. Heart rate-corrected QT interval (QTc) was measured with standard 12-lead electrocardiograms using the MEANS algorithm. The association between QTc and survival was modelled using Cox-regression models (crude- and covariate-adjusted). Values were standardized by dividing the QTc by the standard deviation. The association between QTc and survival was assessed in terms of tertiles of echocardiographic parameters.

Results

In covariate-adjusted models, QTc was associated with general mortality (hazard ratio (HR): 1.19; 95% confidence interval (CI): 1.03, 1.38). Compared with higher tertiles, subjects in the lowest tertile of left ventricular mass index (HR=1.73, 95% CI: 1.26, 2.36) showed the strongest association with general mortality, which was also true for the lowest tertile of diastolic left ventricular posterior wall thickness (HR=1.49, 95% CI: 1.10, 2.02).

Conclusion

In the general population, the association between QTc and general mortality is strongest in subjects with low left ventricular mass index and diastolic thickness of the left ventricular posterior wall, thus the prognostic value of QTc needs to be interpreted with regard to these echocardiographic parameters.

Keywords

Left ventricular mass QT interval mortality general population

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References

Zhang

Post

Blasco-Colmenares

. Electrocardiographic QT interval and mortality: A meta-analysis. Epidemiology 2011; 22: 660–670.

Porthan

Virolainen

Hiltunen

. Relationship of electrocardiographic repolarization measures to echocardiographic left ventricular mass in men with hypertension. J Hypertens 2007; 25: 1951–1957.

Haugaa KH, Martijn Bos J, Borkenhagen EJ, et al. Impact of left ventricular hypertrophy on QT prolongation and associated mortality. Heart Rhythm 2014; 11: 1957–1965.

Soliman

Shah

Boerkircher

. Inter-relationship between electrocardiographic left ventricular hypertrophy and QT prolongation as predictors of increased risk of mortality in the general population. Circ Arrhythm Electrophysiol 2014; 7: 400–406.

Marionneau

Brunet

Flagg

. Distinct cellular and molecular mechanisms underlie functional remodeling of repolarizing K+ currents with left ventricular hypertrophy. Circ Res 2008; 102: 1406–1415.

Greiser

Kluttig

Schumann

. Cardiovascular disease, risk factors and heart rate variability in the elderly general population: Design and objectives of the CARdiovascular disease, Living and Ageing in Halle (CARLA) Study. BMC Cardiovasc Disord 2005; 5: 33.

Rickham

. Human experimentation. Code of ethics of the World Medical Association. Declaration of Helsinki. Br Med J 1964; 2: 177.

van Bemmel

Kors

van Herpen

. Methodology of the modular ECG analysis system MEANS. Methods Inf Med 1990; 29: 346–353.

Kors

van Herpen

. Methodology of QT-interval measurement in the modular ECG analysis system (MEANS). Ann Noninvasive Electrocardiol 2009; 14(Suppl. 1): S48–S53.

10.

Bazett

. An analysis of the time-relations of electrocardiograms. Heart 1920; 7: 35–70.

11.

Lang

Bierig

Devereux

. Recommendations for chamber quantification: A report from the American Society of Echocardiography's Guidelines and Standards Committee and the Chamber Quantification Writing Group, developed in conjunction with the European Association of Echocardiography, a branch of the European Society of Cardiology. J Am Soc Echocardiogr 2005; 18: 1440–1463.

12.

Goldenberg

Moss

Zareba

. QT interval: How to measure it and what is ‘normal’. J Cardiovasc Electrophysiol 2006; 17: 333–336.

13.

Levey

Stevens

Schmid

. A new equation to estimate glomerular filtration rate. Ann Intern Med 2009; 150: 604–612.

14.

Textor

Hardt

Knüppel

. DAGitty: A graphical tool for analyzing causal diagrams. Epidemiology 2011; 22: 745.

15.

R Core Team. A language and environment for statistical computing. Vienna, Austria: R Foundation for Statistical Computing, 2013.

16.

Gosse

Jan

Coulon

. ECG detection of left ventricular hypertrophy: The simpler, the better? J. Hypertens 2012; 30: 990–996.

17.

Medenwald

Kors

Loppnow

. Inflammation and prolonged QT time: Results from the Cardiovascular Disease, Living and Ageing in Halle (CARLA) study. PLoS ONE 2014; 9: e95994.

18.

Kang

. Cardiac hypertrophy: A risk factor for QT-prolongation and cardiac sudden death. Toxicol Pathol 2006; 34: 58–66.

19.

Johnson

Grifoni

Bos

. Prevalence and clinical correlates of QT prolongation in patients with hypertrophic cardiomyopathy. Eur Heart J 2011; 32: 1114–1120.

20.

Wang

Liang

Lan

. Genome editing of isogenic human induced pluripotent stem cells recapitulates long QT phenotype for drug testing. J Am Coll Cardiol 2014; 64: 451–459.

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