Relationship between Tei index of myocardial performance and left ventricular geometry in Nigerians with systemic hypertension.

INTRODUCTION: Left ventricular geometry is associated with cardiovascular events and prognosis. The Tei index of myocardial performance is a combined index of systolic and diastolic dysfunction and has been shown to be a predictor of cardiovascular outcome in heart diseases. The relationship between the Tei index and left ventricular geometry has not been well studied. This study examined the association between the Tei index and left ventricular geometry among hypertensive Nigerian subjects. METHODS: We performed echocardiography on 164 hypertensives and 64 control subjects. They were grouped into four geometric patterns based on left ventricular mass and relative wall thickness. The Tei index was obtained from the summation of the isovolumic relaxation time and the isovolumic contraction time, divided by the ejection time. Statistical analysis was done using SPSS 16.0. RESULTS: Among the hypertensive subjects, 68 (41.4%) had concentric hypertrophy, 43 (26.2%) had concentric remodelling, 24 (14.6%) had eccentric hypertrophy, and 29 (17.7%) had normal geometry. The Tei index was significantly higher among the hypertensives with concentric hypertrophy (CH), concentric remodelling (CR) and eccentric hypertrophy (EH) compared to the hypertensives with normal geometry (0.83 ± 1.0, 0.71 ± 0.2, 0.80 ± 0.2 vs 0.61 ± 0.2, respectively). The Tei index was higher among hypertensives with CH and EH than those with CR. Stepwise regression analysis showed that the Tei index was related to ejection fraction, fractional shortening and mitral E/A ratio. CONCLUSION: Among Nigerian hypertensives, LV systolic and diastolic functions (using the Tei index) were impaired in all subgroups of hypertensive patients according to their left ventricle geometry compared to the control group. This impairment was more advanced in patients with concentric and eccentric hypertrophy.

Metabolic syndrome: comparison of occurrence using three definitions in hypertensive patients.

OBJECTIVE: To compare the frequency of occurrence of metabolic syndrome using three international definitions and to study the distribution of cardiovascular risk factors among newly diagnosed hypertensive Nigerian subjects. DESIGN: Cross sectional study. SETTINGS: Cardiology unit of LAUTECH Teaching Hospital, Osogbo, Nigeria. PARTICIPANTS: One hundred forty newly diagnosed hypertensive Nigerian subjects, and 70 normotensive controls (age- and sex-matched) were included in this study. METHODS: Clinical history and relevant laboratory investigations were performed on all study participants. The definition of metabolic syndrome was based on three international definitions: World Health Organization (WHO), International Diabetes Federation (IDF), and National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III). Ethical approval was obtained for the study. Statistical analyses were performed using SPSS 16.0. RESULTS: There was no difference in age and gender distribution between the hypertensive subjects and controls. (55.14 ± 10.83 years, females 53.6% vs. 54.67 ± 10.89 years, females 52.9% respectively, P>0.05). The frequency of occurrence of metabolic syndrome among hypertensives was 34.5% according to WHO, 35.0% according to NCEP ATP III, and 42.5% according to IDF criteria. Visceral obesity and reduced high-density lipoprotein (HDL) were the other common cardiovascular risk factors among newly diagnosed hypertensive subjects. Female hypertensives had a higher prevalence of visceral obesity and low HDL. CONCLUSION: Frequency of occurrence of metabolic syndrome was similar using the NCEP ATP III and WHO definitions. However, the IDF definition resulted in a higher frequency because of the lower cut-off for waist circumference used for identification of visceral obesity. Metabolic syndrome is present in a significant proportion of newly diagnosed hypertensive subjects. Therefore, appropriate screening and treatment are required.

Dyslipidemia among newly diagnosed hypertensives: pattern and clinical correlates.

BACKGROUND: Hypertension and dyslipidemia are closely interrelated. We aim to determine the prevalence of dyslipidemia among newly diagnosed Nigerian hypertensive subjects and its associated clinical correlates. MATERIALS AND METHODS: This was a cross-sectional study done at the Ladoke Akintola University of Technology (LAUTECH) Teaching Hospital, Osogbo, southwest Nigeria. One hundred sixty-three newly diagnosed hypertensive subjects and 88 controls were recruited and formed the study groups. Relevant history, examinations, and laboratory investigations were performed. Lipid parameters and atherogenic indices were determined. SPSS 16.0 was used for statistical analysis. RESULTS: Hypertensive subjects and controls were well matched in age and gender distribution. Dyslipidemia was more common among the hypertensive subjects. Ninety-six (58.9%) newly diagnosed hypertensive subjects had at least 1 impaired lipid profile. Sixty-seven (41.1%) of them had isolated dyslipidemia, while 29 (17.8%) had combined dyslipidemia. Common patterns of dyslipidemia include low high-density lipoprotein cholesterol (HDL-C), 78 (47.9%); high atherogenic index (total cholesterol/HDL-C), 40 (24.5%) and elevated low-density lipoprotein cholesterol (LDL-C) in 38 (23.3%) subjects. Fasting blood glucose increased as the severity of dyslipidemia increased. CONCLUSIONS: A significant proportion of newly diagnosed hypertensive subjects have dyslipidemia. Low HDL-C was the most common type of dyslipidemia in this study. The use of statins and other supportive therapy is therefore justified among newly diagnosed Nigerian hypertensive subjects with isolated or combined dyslipidemia.

Prevalence of left ventricular diastolic dysfunction in newly diagnosed Nigerians with systemic hypertension: a pulsed wave Doppler echocardiographic study.

BACKGROUND: Systemic hypertension is a common cause of left ventricular diastolic dysfunction. However, its prevalence in Nigerians with untreated systemic hypertension is unknown. OBJECTIVE: To determine the prevalence of left ventricular diastolic dysfunction in newly diagnosed Nigerians with systemic hypertension using Doppler transmitral inflow and pulmonary venous flow velocities. METHODS: Two-dimensional echocardiography including Doppler was performed on 150 newly diagnosed cases of systemic hypertension and 150 normotensive controls. They were divided into hypertensives without left ventricular hypertrophy and those with left ventricular hypertrophy based on echocardiographically determined left ventricular mass index. Pulsed Doppler transmitral inflow and the pulmonary venous flow waves were used to categorise the patterns of diastolic dysfunction. RESULTS: The hypertensives and the normotensive controls were comparable in their baseline characteristics. The E/A ratio differed significantly between hypertensives with and without left ventricular hypertrophy and controls (1.00+0.30, 1.04±0.42, 1.33±0.27, p < 0.001). Left ventricular diastolic dysfunction occurred in 62% of systemic hypertension and 11.3% of the controls. Impaired relaxation was the commonest pattern (84.9%) of diastolic dysfunction. CONCLUSION: Our study showed that left ventricular diastolic dysfunction is prevalent in Nigerians with newly diagnosed systemic hypertension and effort should be made to routinely screen for them.

Relationship between left ventricular diastolic function and geometric patterns in Nigerians with newly diagnosed systemic hypertension.

BACKGROUND: It is not known whether abnormalities of left ventricular diastolic function are influenced by the various cardiac geometric patterns in Nigerians with newly diagnosed systemic hypertension. OBJECTIVE: To evaluate the relationship between the parameters of left ventricular diastolic function and the geometric patterns in this group of patients. METHODS: Two-dimensional, guided M-mode echocardiography including Doppler was performed in 150 consecutive, newly diagnosed hypertensive individuals and normotensive controls aged between 35 and 74 years. Left ventricular mass index and relative wall thickness were used to classify the hypertensive individuals into four geometric patterns, and the pulsed-wave Doppler parameters obtained were used to categorise the abnormalities of diastolic function. RESULTS: Four left ventricular geometric patterns were identified: 23 (15.3%) had normal left ventricle geometry, 33 (22%) had concentric remodelling, 37 (24.7%) were found to have eccentric hypertrophy, and concentric hypertrophy occurred in 57 (38%) of the hypertensive individuals. Left ventricular diastolic dysfunction occurred more in hypertensives with concentric left ventricular geometric pattern. Increased left ventricular mass index and relative wall thickness were found to be associated with the mitral E-wave, E/A ratio and pulmonary venous flow S-wave in the hypertensives (p < 0.001). CONCLUSION: In newly diagnosed Nigerian hypertensives, the abnormalities in left ventricular diastolic function varied between the different left ventricular geometric patterns, being worst in those with concentric geometry.