Diuretic induced long term hemodynamic changes in hypertension. A retrospective study in a MRFIT clinical center.

Retrospective analysis of hemodynamic factors was performed on hypertensive participants of our Multiple Risk Factor Intervention Trial (MRFIT) center to determine whether these may have a role in the higher mortality in a subgroup of special intervention (SI) participants with minor baseline electrocardiographic abnormalities. Stroke volume was estimated by a formula [SV = K(LVETxPP)x(1 + LVET/DP) where the K factor was determined using a separate group of individuals undergoing cardiac catheterization. The Pearson correlation between the two methods (dye dilution and above formula) was 0.

Antihypertensive effect of tiapamil from ambulatory and clinic methods.

Tiapamil (T), a calcium antagonist, was studied in hypertensive patients by 1) automatic monitor of blood pressure (AMBP), and 2) cuff and stethoscope clinic blood pressure (CBP). Systolic (SBP), diastolic (DBP) pressures and heart rate were measured. Patients (n = 58) received four weeks of placebos given twice daily.

Muscular, respiratory and cardiovascular responses of quadriplegic persons to an F. E. S. bicycle ergometer conditioning program.

Seven quadriplegic subjects participated in F. E. S.

Effects of thiazide on erythrocyte sodium and potassium concentrations and Na+K+ATPase in hypertensive patients.

The mechanism of thiazide induced sodium and potassium transport across the cell membranes of humans has not been extensively studied. To assess the effects of thiazide diuretics on erythrocyte sodium transport and potassium distribution we measured intracellular sodium and potassium, sodium-potassium ATPase activity (with and without ouabain) and total body potassium in normokalemic and mildly hypokalemic hypertensive patients. We also measured serum and urine sodium, potassium, calcium and magnesium, plasma renin activity and serum aldosterone levels.

Mechanism of diuretic-induced hypopotassemia in human hypertension.

Diuretic treatment (hydrochlorothiazide) induced a marked decrease of red cell membrane Na+K+ ATPase activity in excessive potassium loser hypertensive patients. The decreased activity occurred within 2-4 weeks of treatment and returned to baseline in 4-6 weeks after cessation of treatment. Simultaneously, red cell sodium increased, potassium decreased together with increased 24-h urinary excretion.

Blood pressure, electrolytes, and body size: their relationships in young relatives of men with essential hypertension.

In 154 white chldren aged 8 to 18 years from four large kindreds, relationships among blood pressure (BP), age, sex, body size, and electrolyte excretion were studied. Each kindred was ascertained through one male aged 35-58 years with essential hypertension, namely, a diastolic blood pressure (DBP) over 95 mm Hg. Weight, relative weight (relative to NCHS median for age, sex, and stature), subcutaneous fatfolds, various indices of obesity, and other measures of body size were significantly correlated with systolic blood pressure (SBP) and DBP in each sex (r = 0.

Cardiovascular response to cooling of limbs determined by noninvasive methods.

Cold, even local exposure to a limited portion of the body, is a stress to man which elevates arterial pressure, thereby intensifying cardiac workload. The sequence of cardiac events following local cooling was noninvasively studied by observation of changes in cardiac interval, left ventricular ejection time, time from A wave of electrocardiogram to the peak of the dD/dt of the carotid pulse wave (which includes pre-ejection period), and amplitude of the pulse wave from a photoelectric cell on the earlobe, along with arterial pressures. Twelve subjects, aged 22--41 years, exposed a hand or foot to cold water for 1 min while seated and while supine (four experiements each).

Cardiac reflexes conducted by vagal afferents in normotensive and renal hypertensive dogs.

1. The renal sympathetic reflex responses to transient balloon occlusion of the descending aorta (systemic baroreceptor activation) and the ascending aorta (cardiac stretch-receptor activation) have been studied together with blood pressure increases after successive cutting of carotid sinus, aortic and vagus nerves in acute experiments in the dog. 2.