Echocardiographic features and QT dispersion in borderline isolated systolic hypertension in the elderly

P-wave and QT dispersion in hypertensive disorders of pregnancy

Aim: To compare P-wave and QT dispersion values in hypertensive disorders of pregnancy and controls and also in preeclampsia, chronic hypertension, and gestational hypertension separately.Material and methods: We included 140 hypertensive pregnants and 110 healthy age-matched pregnants in this study. The hypertensive pregnants were divided into three subgroups: preeclampsia (n = 43), chronic hypertension (n = 51), and gestational hypertension (n = 46). P-wave and QT dispersion values were compared between groups.Results: Hypertensive pregnants had higher P-wave (41.74 ± 5.51 vs. 37.73 ± 5.62, p < .001) and QTc dispersion (45.44 ± 7.62 vs. 39.77 ± 8.34, p < .001) values. In subgroup analysis, P-wave dispersion and QTc dispersion were different between preeclamptic, chronic hypertensive, and gestational hypertensive patients. Also, they were significantly higher in chronic hypertension as compared to gestational hypertension and they were higher in preeclampsia than in gestational hypertension. No difference was found according to these parameters between preeclampsia and chronic hypertension. In correlation analysis, both P-wave dispersion and QTc dispersion were positively correlated with systolic (r = 0.409, p < .001 and r = 0.306, p < .001) and diastolic blood pressure (r = 0.390, p < .001 and r = 0.287, p < .001) which are main clinical determinants of hypertensive disorders.Conclusion: In clinical practice, chronic hypertensive pregnants are generally followed up in their future life for cardiovascular disorders. Also, we recommend that we must inform and follow preeclamptic patients for future cardiovascular diseases.

Would corrected QT dispersion predict left ventricular hypertrophy in hypertensive patients?

AIMS

We explored whether QT corrected dispersion (QTcD) can identify left ventricular hypertrophy (LVH) in hypertensives.

METHODS

We enrolled 100 hypertensive patients (study group) and 30 normotensive subjects (control group). Echocardiography was performed to measure left ventricular mass and left ventricular mass index. Electrocardiogram was performed to measure QTcD.

RESULTS

LVH was present in 42 patients (42%) of the study group, none among controls. Hypertensive patients had significantly greater indices of LVH and QTcD compared with controls (p <0.001 for all). Similarly, among hypertensive patients, those with LVH had a significantly greater QTcD compared with those without (p <0.001). Pearson's correlation coefficient test demonstrated strongly positive correlations between QTcD and the indices of LVH (p <0.001 for all). Analysis of the receiver operating characteristic curves identified 60 ms as the optimal cut-off value of QTcD that best predicts LVH in hypertensives. Using this value, QTcD was able to predict LVH with a sensitivity of 92.9% and specificity 98.2%.

CONCLUSIONS

QTcD is significantly increased in hypertensive patients with LVH compared with those without, being strongly correlated with the indices of LVH. A QTcD cut-off value of 60 ms predicted LVH in hypertensive patients with a high sensitivity and specificity.

Prognostic evaluation of QT-dispersion in elderly hypertensive and normotensive patients

BACKGROUND

QT-corrected interval dispersion (QTcD) is an indirect index of increased heterogeneity of ventricular repolarization. However, the prognostic value of (QTcD) in elderly hypertensive and normotensive patients has not been thoroughly investigated yet.

METHODS

The study population consisted of 60 consecutive patients (34 males/26 females; mean age: 63+/-11 years) with mild to moderate essential arterial hypertension and 48 consecutive age-matched healthy subjects (24 males/24 females; 65+/-16 years). QTcD was measured by a 12-lead electrocardiogram (ECG) as the difference between maximum and minimum QT-interval, corrected for heart rate. Ventricular arrhythmias were recorded by a 24-hour Holter ECG and classified by a modified Lown's score (range: 0-6). Left ventricular mass was measured echocardiographically and indexed by body surface area [left ventricular mass index (LVMI)]. Nine patients were lost during the follow-up period. Patients were followed up for 54+/-9 months, and the primary end-point was the major cardiovascular events (including cardiac mortality).

RESULTS

Major cardiovascular events occurred in 22 patients (22%). Patients with QTcD>or=45 ms (n=35) had a higher rate of major cardiovascular events (43% vs 11%; log rank: 14.8; P<0.001), a higher LVMI (146+/-29 vs 104+/-21 g/m2; P<0.001), greater values of systolic and diastolic blood pressure (154+/-16 vs 144+/-18 mmHg; P<0.01 and 92+/-10 vs 88+/-8 mmHg; P<0.05, respectively), a higher number of premature ventricular beats (354+/-870 vs 113+/-301; P<0.05), and a greater Lown's score (3.7+/-1.9 vs 1.4+/-1.8; P<0.05) than patients with QTcD<45 ms. QTcD (>or=or<45 ms) was an independent predictor of major cardiovascular events (odds ratio: 4.9; 95% confidence interval: 2.0-12.1; P=0.001) after adjustment for LVMI, Lown's score (>or=or<3), age (>or=or<65 years), and QTc max (>or=or<437 ms).

CONCLUSIONS

QTcD is an independent predictor of major cardiovascular events in elderly hypertensive and normotensive patients and might be used in their risk stratification.

QT dispersion and left ventricular hypertrophy in elderly hypertensive and normotensive patients

Inhomogeneity of ventricular repolarization as detected by QT dispersion may be a potential leading mechanism of sudden death in hypertensive and normotensive (age related) left ventricular hypertrophy. Aim of this study was to investigate QT dispersion, ventricular arrhythmias, and left ventricular mass index in elderly hypertensive and normotensive patients. Study population consisted of 60 consecutive patients (sex: 34 men/26 women; age: 63 +/- 11 years) with essential arterial hypertension and 48 age and sex-matched control subjects (24 men/24 women; 64 +/- 16 years). Measurements included QTc dispersion, ventricular arrhythmias, and left ventricular hypertrophy. Hypertensive patients had greater left ventricular mass index (P = .006) and higher QTc dispersion (P = .004) than controls. Left ventricular hypertrophy was diagnosed in 57 (31 men/26 women) of all subjects. These patients had higher blood pressure (P < .05), Lown's score (P < .001), and QTc dispersion (P < .001). QTc dispersion and Lown's score were independent predictors of left ventricular mass index (P < .001). Conclusively, QTc dispersion is a strong indicator of left ventricular mass index and might be used in risk stratification of hypertensive and normotensive elderly patients.