[A comparative study of the effects of lisinopril and quinapril administered once a day in essential hypertension]. / Studio comparativo degli effetti del lisinopril e del quinapril in monosomministrazione giornaliera nell'ipertensione essenziale.

The aim of the study was to compare efficacy and safety of quinapril and lisinopril once-daily administered in patients with mild to moderate hypertension. After a two-week placebo period, 23 patients with sitting diastolic blood pressure between 95 and 110 mmHg were randomly assigned to the therapy with quinapril 20 mg/die or lisinopril 10 mg/die for 4 weeks in a single-blind design. After 4 weeks patients with diastolic blood pressure greater than 90 mmHg were treated with a higher dose (lisinopril 20 mg/die; quinapril 40 mg/die). Therapy with lisinopril normalized 83% of patients, and quinapril 45% of patients. Lisinopril was significantly better than quinapril in reducing blood pressure after 4 and 8 weeks of active treatment. The 24 hours ambulatory blood pressure monitoring showed that quinapril failed to control blood pressure after 12 hours from the administration of the drug.

Changes in blood pressure and thermographic values resulting from use of a beta-blocker plus diuretic and of an alpha-beta-blocker plus diuretic.

Changes in arterial blood pressure and in thermographic values were evaluated in two groups of 15 hypertensive patients, each of which was treated, on a random basis, with a combination of atenolol plus chlorthalidone or a combination of labetalol plus chlorthalidone. Both combinations produced a statistically significant reduction in blood pressure values (p less than 0.01) with no changes in heart rate. Telethermographic investigations revealed the presence of hypothermia of the hands before treatment in all the hypertensive patients examined, but not in the control group (10 normal subjects with no vascular and/or hyperthermic disease). After one month of treatment, no changes in peripheral vascularization were observed in the group treated with atenolol plus chlorthalidone, except for 4 cases showing mild improvement, probably due to a reduction in peripheral resistance as a result of the treatment and to a consequent increase in blood flow in the area investigated. In the group treated with labetalol plus chlorthalidone, on the other hand, a substantial recovery of vascular flow was observed in 12 patients as a result of the treatment, while the remaining 3 patients showed a fair degree of improvement (2 degrees C). Both preparations lent themselves to simplified administration regimens with good patient compliance and no adverse reactions.

[Increased digitalis-like activity in combined administration of calcium antagonists and digitalis preparations]. / Aumentata attività digitalica nella somministrazione contemporanea di calcioantagonisti e digitalici.

It is well recognized that the co-administration of some drugs to persons receiving digoxin results in an increase of serum digoxin levels: it occasionally precipitates digoxin toxicity. There are some possible mechanisms by which different drugs may increase serum glycoside levels: 1) by displacing digoxin from tissue binding sites, 2) by decreasing digoxin renal excretion, 3) by enhancing digoxin absorption, 4) by increasing the inhibition of the ATP-dependent pump. Combined administration of calcium antagonists and B-methyldigoxin is common in patients with heart diseases. Other Authors have found that the co-administration of these drugs with digoxin increases glycoside serum levels, without signs of intoxication. We have examined the effects of this combination on digitalis activity, by Rubidium 86 uptake in erythrocytes. Thirty patients aged 52 to 66 with congestive heart failure were studied. All of these had normal serum creatinine, blood urea and serum protein levels. These subjects received 0,20 mg of B-methyldigoxin daily for nine days; afterwards, ten of them were given in addition 320 mg of verapamil for seven days; the other ten received in addition 60 mg of nifedipine, for seven days; the remaining ten patients received in addition 320 mg of verapamil and 60 mg of nifedipine together, for seven days. Digoxin activity was measured on the eighth, ninth and sixteenth day of treatment by Rubidium 86 uptake in erythrocytes. The technique was that of Bertler. Means were compared with the t test, with the assumption of the equal variances in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Interaction between verapamil and beta-methyldigoxin. Study by 86Rubidium uptake in erythrocytes.

Digoxin and Verapamil may often be used in association in heart diseases; we tested whether this coadministration increases digitalis activity. Ten patients with failing heart were given 0.10 mg of beta-methyldigoxin, twice a day, for nine days; then they received in addition 80 mg of Verapamil, four times a day, for seven days. Digoxin activity was measured on the eighth, ninth and 16th days of treatment by 86Rubidium uptake in erythrocytes. The steady-state concentration was 0.91 +/- 0.13 ng/ml; during the coadministration the concentration rose to 1.23 +/- 0.16 ng/ml (an increase of 35.12%). The change was significant (p less than 0.001). The mechanism of this increase is unknown: it is important that there exists an increase in digitalis activity and not only a haematic elevation.