To define the prevalence and prognosis of ECG abnormalities in hypertensive individuals.
ECG, blood pressure and other cardiovascular risk factors were recorded in a nationwide population sample of 5800 Finns. The presence of 15 ECG abnormalities was evaluated. Participants were divided into categories by blood pressure and followed for coronary heart (CHD) and cardiovascular disease (CVD) events.
Mean follow-up was 10.4 ± 2.2 years. The age- and sex-adjusted prevalence rates of ECG abnormalities were generally higher in the hypertensive participants than in normotensive individuals. In multivariable-adjusted Cox models, the following ECG abnormalities predicted CHD in hypertensive participants: left ventricular hypertrophy (LVH) by Sokolow-Lyon criteria [hazard ratio, 1.47; 95% confidence interval (CI), 1.07–2.01; P = 0.02], LVH with ST-depression and negative T wave (ST/T changes) (hazard ratio, 2.31; 95% CI, 1.20–4.43, P = 0.01), ST/T changes (hazard ratio, 2.12; 95% CI, 1.34–3.36; P = 0.001), positive T wave in lead aVR (AVRT+) (hazard ratio, 1.74; 95% CI, 1.15–2.64; P = 0.009) and poor R-wave progression (hazard ratio, 2.02; 95% CI, 1.27–3.22; P = 0.003). These ECG abnormalities were also significant predictors of CVD in hypertensive participants (P ≤ 0.03 for all). Nonspecific intraventricular conduction delay predicted CVD in the whole population (hazard ratio, 1.50; 95% CI, 1.06–2.13; P = 0.02). Prolonged QT interval, abnormal P-wave indices, left axis deviation and early repolarization pattern were not associated with CHD or CVD.
ECG abnormalities are highly prevalent in hypertensive individuals. LVH is still the cornerstone of cardiovascular risk assessment in hypertensive patients. The additional assessment of ST/T changes, AVRT+ and poor R-wave progression in ECGs could improve risk prediction in hypertensive patients.
aDepartment of Health, National Institute for Health and Welfare Turku
bDivision of Medicine, Turku University Central Hospital, Turku
cDivision of Cardiology, Heart and Lung Center, Helsinki University Central Hospital, Helsinki
dMedical Research Center, Oulu University Central Hospital and University of Oulu, Oulu
eDivision of Internal Medicine, Seinäjoki Central Hospital, Seinäjoki
fHeart Center, Tampere University Hospital and School of Medicine, Tampere University
gDepartment of Clinical Physiology, University of Tampere and Tampere University Hospital, Tampere, Finland
hFramingham Heart Study, Framingham, Massachusetts, USA
Correspondence to Arttu O. Lehtonen, MD, Department of Health, National Institute for Health and Welfare, P.O. Box 57, 20521, Turku, Finland. Tel: +358 40 0249183; e-mail: email@example.com
Abbreviations: AUC, area under receiver-operating characteristic curve; AVRT+, positive T wave in lead aVR; CI, confidence interval; IDI, integrated discrimination index; IVCD, nonspecific intraventricular conduction delay; LVH, left ventricular hypertrophy; PTF, P terminal force; ST/T changes, ST-depression with negative T wave
Received 18 November, 2015
Revised 12 January, 2016
Accepted 18 January, 2016