Impact of prehypertension on left ventricular mass and QT dispersion in adult black Nigerians : cardiovascular topic

Abstract

SummaryBackgroundPrehypertension 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.MethodsOne hundred and one subjects with office blood pressure (BP) < 140/90 mmHg were categorised according to their office BP into normotensive (BP < 120/80 mmHg, n = 57) and prehypertensive (BP 120–139/80–89 mmHg, n = 44) groups. Echocardiography and electrocardiography (ECG) were performed on the subjects.ResultsThirty-four males aged 53.65 ± 16.33 years and 67 females aged 52.42 ± 12.00 years were studied. The mean QT interval dispersion (QTd) 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/m2, p = 0.021) and left ventricular mass index 2 (LVMI-2) (54.96 ± 10.84 vs 47.51 ± 12.00 g/m2.7, p = 0.017). QTd was independent of echocardiographic and electrocardiographic LVH (p > 0.05).ConclusionCompared with normotension, prehypertension is associated with higher LVM but similar QTd. This suggests that structural remodelling precedes electrical remodelling in prehypertension.

Tp-e/QT ratio and QT dispersion with respect to blood pressure dipping pattern in prehypertension

“…normotensives [18], although their study participants had far higher LVMI than the participants in the study by Doğru et al [10] and the participants of our study.…”

Echocardiographic Assessment of the Left Ventricle in Young Prehypertensive Nigerians

“…Our study showed that the LVMI was significantly higher in prehypertensive subjects than in normotensive subjects. This correlates with the work of Ale et al [10] in Nigeria and other studies [21,22], including the Strong Heart Study [7]. The findings of a significantly higher left ventricular internal diameter in diastole (LVIDd), left ventricular posterior wall in diastole (LVPWd), and relative wall thickness (RWT) in prehypertensive individuals in the current study corroborate the ARIC (Atherosclerosis Risk in Communities) study [23] where LVIDd and LVPWd were significantly higher in prehypertensive subjects compared to normotensive controls amongst Americans.…”

“…To our knowledge, no study has examined LV geometry and function in young Nigerians with prehypertension. The few studies conducted on LV geometry in Nigeria mostly studied hypertensive subjects, and the results from these studies were correlated to international studies; abnormal LVMI with a predominant pattern of concentric left ventricular hypertrophy (LVH) [ 10 , 11 ]. In addition, the participants in these studies were middle-aged, with a sparse representation of young patients.…”

Prevalence and Risks Factors of Prehypertension in Africa: A Systematic Review

“…Nwatu et al [27] have shown that impaired glucose tolerance were significant predictors of prehypertension. Ale et al [34] measured the impact of prehypertension on some electrocardiographics and echographic factors. They noticed that compared with normotension, prehypertension was associated with higher left ventricular mass and higher left ventricular mass index.…”