Impact of prehypertension on left ventricular mass and QT dispersion in adult black Nigerians.
BACKGROUND
Prehypertension has been associated with target-organ damage. This study sought to determine the impact of prehypertension (PHT) on QT dispersion and left ventricular hypertrophy (LVH) in adult black Nigerians.


METHODS
One hundred and one subjects with office blood pressure (BP) < 140/90 mmHg were categorised according to their office BP into normotensive (normal BP < 120/80 mmHg, n = 57) and prehypertensive (prehypertensive BP 120-139/80-89 mmHg, n = 44) groups. Echocardiography and electrocardiography (ECG) were performed on the subjects.


RESULTS
Thirty-four males aged 53.65 ± 16.33 years and 67 females aged 52.42 ± 12.00 years were studied. The mean QT interval dispersion (QT(d)) of the normotensive (38.96 ± 11.06 ms) and prehypertensive (38.41 ± 11.81 ms) groups were similar (p = 0.81). Prehypertensive subjects had higher left ventricular mass (LVM) (165.75 ± 33.21 vs 144.54 ± 35.55 g, p = 0.024), left ventricular mass index 1 (LVMI-1) (91.65 ± 16.84 vs 80.45 ± 18.65 g/m(2), p = 0.021) and left ventricular mass index 2 (LVMI-2) (54.96 ± 10.84 vs 47.51 ± 12.00 g/m(2.7), p = 0.017). QT(d) was independent of echocardiographic and electrocardiographic LVH (p > 0.05).


CONCLUSIONS
Compared with normotension, prehypertension is associated with higher LVM but similar QT(d). This suggests that structural remodelling precedes electrical remodelling in prehypertension.
Department of Medicine, College of Medicine, University of Lagos/Lagos University Teaching Hospital, Lagos, Nigeria.
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Department of Medicine, College of Medicine, University of Lagos/Lagos University Teaching Hospital, Lagos, Nigeria.
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Ajuluchukwu
Department of Medicine, College of Medicine, University of Lagos/Lagos University Teaching Hospital, Lagos, Nigeria.
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Ok
Department of Medicine, College of Medicine, University of Lagos/Lagos University Teaching Hospital, Lagos, Nigeria.
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Mbakwem
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000379:methods; D004452:Echocardiography / Q000379:methods; D004562:Electrocardiography / Q000379:methods; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D009549:Nigeria; D058246:Prehypertension / Q000150:complications* / Q000503:physiopathology