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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to study the hemodynamic effects of the antihypertensive drugs in patients with essential hypertension, systolic time intervals from ECG data were extrapolated. The study was performed in 36 healthy individuals and 38 patients with essential hypertension without a drug therapy and/or in the wash out period more than three weeks and after a treatment. The stroke volume (SV) was determined as a product of the ejection time (ET), the pulse pressure (PP) and the flow coefficient (Kf). The Kf was extrapolated from Doppler-cardiographic parameters and it significantly correlated with the normal diastolic blood pressure (TA(d)) if the QT is not prolonged and the electrical systole/mechanical systole ratio (QS2/MS) not disturbed: Kf = 9.356 e-0.008 TA(d); r = -0.9. In arterial hypertension the correlation was also curvilinear: kf = 3.962 e-0.001 TA(d); r = -0.99. The arteriolar stiffness was defined as the PP/SV ratio. The cardiac output (CO) and systemic vascular resistance (SVR) were determined according to conventional formulas by known clinical and extrapolated ECG data. The cardiac contractile or muscle performance was defined as corrected changes of the ejection function for the given afterload according to the formula: I (-0.004 TA(d) + PEP/ET) -0.014 x 100; the normal 95% confidence limits for the laboratory used are -6.6% to +6%. Systolic time intervals were extrapolated from ECG data in the consecutive manner: QS2 = kQS2 x QT, ET = kET x JT, and MS = kMS x ET. The correlation of kQS2 with QT is curvilinear: kQS2 = 2.760 e-2.732 QT.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Electrocardiographic and clinical anticipation of the left ventricular systolic function, systemic vascular resistance, and myocardial hypertrophy--normal values and validation of method in patients with arterial hypertension. 138 Mar 56

By using apexcardiography and echocardiography, the diastolic and systolic function of 34 hypertensive patients were studied. The results indicated that left ventricular (LV) hypertrophy is one of the important factors in impairing LV diastolic function in essential hypertension. By using self-control method, Verapamil(V) was injected intravenously. Relative A wave to total diastolic amplitude (A/D), total apexcardiographic relaxation time index (TARTI), diastolic amplitude time index (DATI) and PEP/LVET were measured. After 5 half-lives of V, intravenous Tetrandrine (T) was given, all the measurements were repeated in the same way. The data revealed that A/D, TRATI and DATI improved significantly after intravenous T and V as well, yet PEP/LVET showed no significant change. It, therefore, seems clear that both T and V could induce a significant improvement in LV diastolic function without any apparent adverse influence on systolic function.
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PMID:[Effect of tetrandrine and verapamil on left ventricular diastolic and systolic function in essential hypertension]. 187 78

To investigate the left ventricular preload reserve in essential hypertensives, the legs-up procedure was performed and the data were compared with those in patients with non-obstructive hypertrophic cardiomyopathy and in normal subjects. Stroke volume index and the following systolic time intervals were measured before and after the legs-up procedure: left ventricular ejection time, pre-ejection period and the ratio of pre-ejection period to left ventricular ejection time (PEP/ET). No changes in blood pressure, heart rate or plasma catecholamine levels were noted before and after the legs-up procedure in all groups. A shortening in the pre-ejection period, a prolongation of ejection time, a decrease in the PEP/ET ratio and an increase in the stroke volume index were observed in essential hypertensives and in normal subjects. However, the changes in these parameters were not observed in patient with hypertrophic cardiomyopathy. The legs-up procedure is known to increase left ventricular end-diastolic volume. These results suggest that myocardial hypertrophy due to essential hypertension preserves the same preload reserve as in normals, but hypertrophic cardiomyopathy does not.
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PMID:Disparate difference in preload reserve between myocardial hypertrophy due to essential hypertension and hypertrophic cardiomyopathy. 297 57

The study involved 13 patients with primary hypertension who exercised on a bicycle ergometer with intensity increasing up to submaximum level. The exercise was carried out in four stages: before treatment (1st study), following one week treatment with 50 mg hydrochlorothiazide daily (2nd study), after one week treatment with the same dose of hydrochlorothiazide and 120 mg binazine daily (3rd study), and after one week treatment with hydrochlorothiazide and binazine, and 60 mg of propranolol daily (4th study). Using the approach of Weissler et al., left ventricular systolic time intervals were analysed at rest, after exercise and up to the 90th minute of restitution. Hydrochlorothiazide and binazine treatment decreased systolic and diastolic blood pressure, the total electromechanical systolic time index (QS2I) and the left ventricular ejection time index (LVETI), and increased the PEP/LVET index at rest and after exercise. Addition of propranolol did not augment the hypotensive effect, while the left ventricular systolic time intervals returned to the values observed before treatment.
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PMID:Post-exertion changes in left ventricular systolic time intervals in patients with primary hypertension treated with hydrochlorothiazide, binazine, and propranolol. 409 41

Heart rate (HR), blood pressure and systolic time intervals (STI), including total electromechanical systole (QS2), left ventricular ejection time (LVETc), pre-ejection period (PEPc), the PEP/LVET index and the time to the peak of carotid upstroke (Ut), were measured in 24 patients with moderate essential hypertension after 15 days of treatment with oral furosemide (F), hydrochlorothiazide (H), propranolol (P), atenolol (A), furosemide + propranolol (F + P) and hydrochlorothiazide + propranolol (H + P). Except F, all treatments significantly reduced blood pressure; maximal reductions were brought about by A and H + P. The heart rate was most reduced by A. THe QS2c interval was reduced only after F and H, LVETc was significantly reduced by H, A and H + P. Drug combinations prolonged PEPc, while the PEP/LVET index was increased only by H + P. Beta-blockers significantly prolonged the Ut. It is concluded that diuretics shorten QS2c mainly through reduction in blood volume. The H + P combination diminishes contractility and cardiac output and should not be employed in heart failure.
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PMID:Modification of blood pressure and systolic time intervals by diuretics and beta-blockers in essential hypertension. 613 68

Systolic time intervals (STI) were recorded at rest and during isometric exercise (IHG) in 20 hypertensive outpatients, WHO Stage 1 or 2. In a double-blind crossover study, slow-release metoprolol 200 mg once daily and matched placebo were given for 4 weeks each, at the end of a 2-week placebo washout. Blood pressure and STI were taken in the last day of washout and of either crossover period. Treatment decreased blood pressure and heart rate values at rest and on peak IHG; it didn't modify preejection period index (PEPI), left ventricular ejection time index (LVETI), and their ratio at rest, but decreased the ratio between diastolic blood pressure and PEPI (DBP/PEPI ratio) at rest and on peak IHG and lengthened the PEPI at peak IHG. Resting PEPI values on placebo treatment showed a negative correlation with systolic (r = -0.72) as well as diastolic (r = -0.80) pressure reduction on slow-release metoprolol as compared with placebo treatment. The PEP/LVET ratio at rest on placebo treatment showed a negative correlation with systolic (r = -0.78) as well as diastolic (r = -0.82) pressure reduction at rest on metoprolol compared with placebo treatment. Patients with a resting PEP/LVET ratio less than 0.43 showed a reduction in both systolic and diastolic pressure approximating or exceeding 20 mm Hg, whereas patients with a PEP/LVET ratio greater than 0.47 showed a decrease in systolic and diastolic blood pressure of less than 10 mm Hg. In patients with a PEP/LVET ratio of 0.43 to 0.47 (50% of the trial population), STI didn't show any correlation with the pressure response to beta-blockade. A positive correlation was found between the DBP/PEPI ratio at rest on placebo treatment and systolic (r = 0.56) as well as diastolic (r = 0.76) pressure reduction at rest on slow-release metoprolol compared with placebo treatment. Thus, STI appeared as promising predictors of the magnitude of blood pressure response to sustained beta-blocking therapy in mild-to-moderate essential hypertension, mostly in patients with a resting PEP/LVET ratio less then 0.43 or greater then 0.47.
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PMID:Systolic time intervals as possible predictors of pressure response to sustained beta-adrenergic blockade in arterial hypertension. A within-patient, placebo-controlled study. 633 19

In order to clarify the hemodynamic characteristics in essential hypertension (HT) with angina pectoris (AP), systolic time intervals (STIs) were measured in 13 normal subjects (N), 23 patients with AP, 43 HT (WHO stage I: 13, WHO stage II: 23, WHO stage III: 7) and 19 HT with AP (WHO I: 9, WHO II: 10). The ET/PEP ratio was 2.41 +/- 0.24 in N, 2.70 +/- 0.34 in AP (p less than 0.02, vs N), 2.25 +/- 0.29 in WHO I, 2.13 +/- 0.25 in WHO II (p less than 0.01, vs N), 1.54 +/- 0.37 in WHO III (p less than 0.001, vs N), 2.68 +/- 0.32 in WHO I with AP (p less than 0.05, vs N: p less than 0.005, vs HT) and 2.71 +/- 0.30 in WHO II with AP (p less than 0.02, vs N: p less than 0.001, vs HT). Ejection time index (ETI) was 385 +/- 15 msec in N, 399 +/- 16 in AP (p less than 0.05, vs N), 387 +/- 13 in WHO I, 385 +/- 15 in WHO II, 363 +/- 25 in WHO III (p less than 0.05, vs N), 393 +/- 16 in WHO I with AP and 402 +/- 15 in WHO II with AP (p less than 0.05, vs N: p less than 0.01, vs HT). Pre-ejection period index (PEPI) was 142 +/- 10 msec in N, 135 +/- 11 in AP, 148 +/- 12 in WHO I, 156 +/- 13 in WHO II (p less than 0.005, vs N), 192 +/- 24 in WHO III (p less than 0.001, vs N), 134 +/- 13 in WHO I with AP (p less than 0.05, vs HT) and 136 +/- 9 in WHO II with AP (p less than 0.001, vs HT). These results showed that the ET/PEP ratio in HT with AP was significantly higher than that in HT alone, and this increase in ET/PEP ratio was mainly due to the shortening of PEP interval in WHO stage I and the lengthening of ET in addition to it in WHO stage II.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Noninvasive evaluation of left ventricular function by systolic time intervals in essential hypertension with angina pectoris. 651 40

Clinical assessment of a novel antihypertensive drug combination was undertaken in a group of essential hypertensive patients (n = 20). The effects of several doses of clonidine and its association with prazosin on blood pressure (BP), systolic time intervals (STI), and electrocardiogram (ECG) were investigated. Clonidine monotherapy induced a good BP control at 60%. BP was controlled in those patients in which prazosin was combined with clonidine (87.7%). LVETc was reduced by 0.3, 0.6, and 0.9 mg clonidine daily (p less than 0.05). PEPc was increased by only 0.9 mg, and it was diminished after its combination with 20 mg prazosin daily (p less than 0.05). PEP/LVET index was significantly increased by a higher dose of clonidine (p less than 0.05). ECG intervals did not change with the exception of PR, which was prolonged by 0.9 mg clonidine daily (p less than 0.05). Dry mouth, sedation, constipation, and drowsiness were the main side effects observed during the investigation. These results suggest an alternative treatment of essential hypertension, with a novel clinical application of drugs such as clonidine and prazosin, which have pharmacologic action via different alpha-adrenergic mechanisms.
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PMID:Clonidine and prazosin in the treatment of hypertensive outpatients--a preliminary study. 664 91

The clinical effects, the exercise test answer, the left ventricular function by polygraphyc test after administration at middle term of Metoprolol and Labetalol have been evaluated in 20 patients with moderate and non complicated essential hypertension. The study was a double blind cross-over between Metoprolol and Labetalol (270 mg/die per os). Both drugs induced a reduction of PAOS and PAOD. The exercise test induced in all patients a decrease of PAOS and PAOD, showing an improvement of strain tolerance. The normalization of PEP and non modification of LVET seem to confirm that the treatment with Metoprolol and with Labetalol, neither induces significant modification of left ventricular function.
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PMID:[Clinical, ergometric and polygraphic evaluation of the effects of metoprolol and labetalol administration in essential arterial hypertension. Comparative study]. 707 Jun 96

The modifications of systolic times during isometric exercise (hand-grip) are evaluated in a group of patients with essential hypertension. In these patients the hand-grip showed a reduction of the PEP, ICT and LVET: the re-establishment of the basal values of the PEP, ICT and LVET, became in variable times and in different ways with regard to the modifications of the miocardial performance induced by hypertension, unlike normal patients, in whom that becomes normally during the period of recovery. Little modifications of the PEP/LVET ratio, are observed in all patients and this ratio is like that observed toward blood-pressure during exercise. Blood-pressure, like heart rate, increased suddenly during exercise and returned on the basal values during the recovery, normally both in the control group and in patients with hypertension arised recently; more slowly and incompletely in patients with hypertension arised long before. The Authors related this fact to the adjustment alterations of the blood pressure.
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PMID:[Effects of isometric exercise (handgrip) on the systolic times of patients with essential arterial hypertension. A polygraphic study]. 711 Jun 8


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