Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1 Prenalterol, (S-(-)-1-(4 hydroxyphenoxy)-3-isopropylaminopropanol-2 hydrochloride) a cardio-selective beta-adrenergic receptor agonist, was infused intravenously into six normal male volunteers to determine the cardiovascular effects of this drug. 2 On different occasions, each volunteer received a placebo infusion, an infusion of 0.5 mg prenalterol and an infusion of 1 mg prenalterol. Cardiac output (impedance cardiography), arterial pressure (sphygmomanometry), heart rate and ECG were measured throughout. 3 Prenalterol produced a statistically significant increase in cardiac output and at the end of the infusion this increase was 24% with 0.5 mg and 29% with 1 mg, mainly due to an increase in stroke volume (18% and 17%) with a lesser change in heart rate (+2 and +7 beats/min). Pulse pressure increased but mean arterial pressure showed little change. Peripheral resistance fell by 18% and 20%. As indicated by systolic time indices myocardial contractility increased. 4 Prenalterol at plasma concentrations in excess of 20 nmol l-1 produced significant inotropic effects but did not markedly increase heart rate at concentrations of 60 nmol l-1.
 ...
PMID:Cardiovascular effects of prenalterol (H133/22) in normal man. 3 18

Prenalterol was administered as an intravenous infusion at three incremental rates (60, 120 and 240 nmol/min) to five patients with severe cardiac failure. Haemodynamic, hormonal and metabolic variables were measured at the same time as plasma prenalterol concentrations, and the pharmacokinetics of the drug were studied by following plasma concentrations and urinary excretion during and after the infusion. Concentration-dependent increases in cardiac index, stroke index and stroke work index were observed without increases in arterial pressure, heart rate or myocardial oxygen demand. The reninangiotensin-aldosterone system was stimulated, although the extent of stimulation varied among patients. No strong correlations were found between the logarithm of the plasma prenalterol concentration and effect. Plasma clearance of the drug was lower in cardiac patients than in normal volunteers, but a large decrease in renal clearance was partially balanced by an increase in nonrenal clearance. Over the observed range of concentrations, no deviation from linearity was evident, and plasma concentrations of about 150 nmol/l were effective in improving cardiac function without significant side-effects.
 ...
PMID:Pharmacokinetics and plasma-concentration-effect relationships of prenalterol in cardiac failure. 286 51

The immediate haemodynamic effects of prenalterol and nitroglycerine were examined in 15 patients, with severe chronic heart failure. Prenalterol was given intravenously in increasing doses of 2, 4, and 8 mg. Cardiac index increased significantly by 16%, 24%, and 32%, respectively. Heart rate increased by 16%, 19%, and 24%. Stroke volume index, systemic artery pressure, pulmonary artery pressure, and right atrial pressure did not change. Prenalterol reduced systemic vascular resistance by 15%, 17%, and 24%, respectively. Forearm blood flow and forearm vascular resistance was unchanged. Cardiac index and heart rate were not changed by 0.5 mg nitroglycerine, administered sublingually. Systolic and diastolic blood pressure were on average reduced by 14% and 12%, respectively. Systolic and diastolic pulmonary artery pressure and right atrial pressure were similarly reduced by 17%, 31%, and 39%, respectively. Nitroglycerine lowered calculated systemic vascular resistance by 11%, whereas forearm blood flow and forearm vascular resistance was unchanged. The conclusion is that prenalterol acutely increased cardiac index and improved haemodynamics in 14 out of 15 patients, mainly due to an increased heart rate. Nitroglycerine did not change cardiac index in the same group of patients.
 ...
PMID:Prenalterol in severe congestive heart failure. I. The immediate haemodynamic effects as compared to nitroglycerine. 312 10

The acute haemodynamic effects of prenalterol, a selective adrenergic beta-1-receptor agonist, were studied in eight healthy male volunteers. Prenalterol was administered i.v. in five increasing doses to a cumulative dose of 5.55 mg. After the last dose of prenalterol, three doses of the selective adrenergic beta-1-receptor antagonist metoprolol were administered i.v. to a cumulative dose of 17.5 mg. After each dose, cardiac output (CO), stroke volume (SV), blood pressure (BP), heart rate (HR), systolic time intervals (STI) and forearm blood flow (FBF) were determined. Prenalterol had the following effects: CO was significantly increased by 21.0% after the fourth dose, but the fifth dose did not further change CO. SV was unchanged after the first four doses, but after the fifth dose a significant decrease in SV of 7.0% was seen. Mean BP was increased significantly by 7.7%, but diastolic BP remained unchanged. HR was increased by 28.4%. Total peripheral resistance was reduced by 8.8%. STI were reduced significantly after the second dose, which indicates that prenalterol has a positive inotropic action. FBF was increased significantly after the fourth dose. After the third dose of metoprolol, the CO, SV, means BP, HR, STI and FBF had returned to their control values. It is concluded that prenalterol has positive inotropic and chronotropic effects on the myocardium, and that metoprolol is a specific antidote.
 ...
PMID:Immediate haemodynamic effects of prenalterol, a new adrenergic beta-1-receptor agonist, in healthy volunteers. 610 19

The haemodynamic effects of the new selective beta 1-receptor-agonist prenalterol were investigated in two groups each of 8 patients. Dosages of 500 microgram/5 min and 100 microgram/1 min were given after direct closure of atrial septal defect under neuroleptanalgesia. Prenalterol 500 microgram/5 min increased cardiac index (37.5%), heart rate (19%), stroke index (16.2%), mean arterial pressure (26.5%) and dp/dtmax (84.5%) significantly. Total systemic resistance, total pulmonary vascular resistance and mean pulmonary pressure remained constant. Filling pressures of both ventricles decreased slightly but significantly. Maximal hemodynamic changes after infusion of 100 microgram/1 min prenalterol were half as great as with 500 microgram/5 min and occurred 3 min earlier. The haemodynamic action of prenalterol was rather long lasting. One hour after cessation of the drug-infusion there were still detectable haemodynamic effects. In contrast to investigations in awake patients there was a greater increase in heart rate, which is referred to influences on the vagal reflex caused by anaesthesia.
 ...
PMID:[Prenalterol (CGP 7760 B), a new cardioselective beta 1-adrenoceptor-agonist (author's transl)]. 611 33

The hemodynamic effects of a new cardioselective beta agonist, prenalterol, were evaluated in 12 patients with moderate or severe impairment of left ventricular function due to coronary heart disease or primary cardiomyopathy. In doses up to 7 mg the drug led to a substantial increase of left ventricular pressure rise (+55%) and mean circumferential fiber shortening (+59%) and a decrease of left ventricular end-diastolic pressure (-52%), mean pulmonary artery pressure (-24%) and pulmonary vascular resistance (-37%) indicating augmented myocardial contractility and reduced left ventricular preload. Cardiac output was increased only in 4 of 12 patients, heart rate, left ventricular systolic and mean right atrial pressures and the pressure-rate product as an index for myocardial oxygen demand remained essentially unchanged. The same is true for stroke index, stroke work index, total peripheral resistance, left ventricular end-diastolic and end-systolic volume and ejection fraction. The positive inotropic effect was achieved with good tolerance and without arrhythmogenic or other side effects. Prenalterol may be especially useful in patients with low sympathetic activity and hypotension. In patients with diffuse congestive cardiomyopathy, high sympathetic activity, pronounced peripheral vasoconstriction and normal blood pressure, vasodilator therapy alone or in combination with prenalterol should be considered.
 ...
PMID:Hemodynamic assessment of prenalterol: a cardioselective beta agonist in patients with imparied left ventricular function. 612 57

The hemodynamic effects of prenalterol, a parenteral cardioselective beta 1-receptor agonist, were evaluated by cardiac catheterization in patients with refractory severe congestive heart failure (CHF). Prenalterol (PN) (4 mg i.v.) did not alter (p greater than 0.05) heart rate (HR), mean blood pressure (MBP) or left ventricular filling pressure (LVFP). Concomitantly PN markedly augmented cardiac index (CI) from 1.9 to 2.6 l/min/m2 (p less than 0.01) and substantially elevated stroke index (SI) from 24 to 30 ml/beta/m2 (p less than 0.001). In addition PN raised stroke work index (SWI) from 21 to 26 g . m/m2 (p less than 0.005) and decreased total systemic vascular resistance (TSVR) from 1702 to 1260 dyn . s. cm-5 (p less than 0.001). An important finding was that the heart rate x systolic blood pressure product was unchanged (p greater than 0.05) and precipitation of cardiac dysrhythmias or myocardial ischemia were not observed. Further PN 1 mg, 4 mg and 8 mg i.v. was sequentially injected and peak hemodynamic effects were determined 10 min after drug administration. PN 1 mg raised CI from 2.1 to 2.5 1/min/m2 (p less than 0.01), elevated SI from 24 to 29 ml/beat/m2 (p less than 0.01), and augmented SWI from 21 to 25 g . m/m2 (p less than 0.01), however, TSVR declined from 1702 to 1392 dyn . s. cm-5. Subsequent incremental PN doses of 4 and 8 mg did not provide (p greater than 0.05) additional enhancement of cardiac function. Thus, prenalterol produced markedly beneficial enhancement of cardiocirculatory function without untoward effects and may be useful in the management of patients with severe congestive heart failure. Moreover, dose-response analysis indicates these salutary improvements can be maximally produced by the small dose of 1 mg obviating the need for larger doses.
 ...
PMID:The hemodynamic actions of prenalterol in left ventricular failure. 612 93

Prenalterol administration (150 micrograms/kg i.v.) exerted beneficial effects on resting and/or exercise cardiac performance in patients with congestive cardiomyopathy (n = 12) and 1 patient with hypertensive heart disease (= group I, n = 13), while the haemodynamic response in patients with severe coronary heart disease (n=3) or cor pulmonale (n = 1) was non-uniform. At rest mean right and left ventricular filling pressures decreased by 26 and 19% (p less than 0.02 and p less than 0.02), respectively, while stroke volume increased by 8% (p less than 0.05), cardiac index by 25% (p less than 0.01) and heart rate by 15% (p less than 0.005) 5 min after prenalterol administration in group I. During exercise there was no further increase in heart rate, while filling pressures decreased and cardiac index increased significantly compared to control exercise. This typical inotropic response to prenalterol was observed in fully digitalised patients. Maximal effects occurred about 15 min after i.v. administration.
 ...
PMID:Effects of i.v. prenalterol in patients with severe cardiac failure at rest and during exercise. 612 97

Prenalterol, a beta 1 selective agonist, exerts a positive inotropic action in animal studies as well as in human volunteers and is effective when administered orally. To assess its immediate haemodynamic and myocardial metabolic effects, we studied the response to prenalterol (50 and 100 micrograms kg-1 given intravenously by cardiac catheterization) in 15 patients with congestive heart failure secondary to coronary artery disease or non-ischaemic cardiomyopathy. At peak effect, cardiac index increased from 2.6 +/- 0.5 to 3.2 +/- 0.8 l min-1 m2 (mean +/- S.D.) (P less than 0.001); peak rate of left ventricular pressure development rose from 963 +/- 242 to 1335 +/- 411 mmHg s-1 (P less than 0.001); left ventricular end-diastolic pressure fell from 25 +/- 6 to 17 +/- 7 mgHg (P less than 0.001); coronary sinus blood flow increased from 113 +/- 39 to 148 +/- 55 ml min-1 (P less than 0.01); myocardial oxygen consumption was augmented from 12.7 +/- 3.9 to 16.4 +/- 5.8 ml min-1 (P less than 0.001); and heart rate increased slightly (from 76 +/- 12 to 86 +/- 14 beats min-1; (P less than 0.05)). No significant changes occurred in left ventricular systolic pressure, stroke volume index, myocardial lactate extraction rate and myocardial arteriovenous oxygen difference, and no patients developed angina, ECG changes or ventricular arrhythmias. Infusion of prenalterol effectively improved haemodynamic function and cardiac metabolism in cardiomyopathy. Therefore this agent deserves further investigation to evaluate its possible role for the long-term therapy of patients with chronic heart failure.
 ...
PMID:Haemodynamic and cardiac metabolic effects of the new beta 1 agonist prenalterol in patients with cardiac failure. 613 81

The effects of a single intravenous infusion of prenalterol, a beta 1 selective agonist, on haemodynamics (echocardiography) and venous plasma catecholamine concentration were studied in 8 patients with severe congestive heart failure. In these patients, age-adjusted plasma norepinephrine (NE) and epinephrine (E) levels before prenalterol infusion were higher compared to values found in 10 control healthy subjects (both P less than 0.01). In heart failure patients, circulating NE levels were not dissimilar in 2 samples drawn 60 and 0 minutes before commencing prenalterol infusion (772.0 +/- 131 ng/l [mean +/- SD] and 775.5 +/- 130.0 ng/l respectively). Prenalterol induced a significant improvement in the cardiac index, stroke index, ejection fraction and velocity of circumferential fiber shortening, associated with a moderate but significant decrease in peripheral vascular resistance. All these changes persisted for 60 minutes after the end of infusion. Circulating NE levels were 604.0 +/- 125 ng/l at 60 min. after start of infusion (P less than 0.01 vs pre-infusion levels) and 526.1 +/- 108 ng/l at 60 min. after the end of infusion (P less than 0.01 vs pre-infusion levels). Plasma E showed a slight decrease, which did not attain statistical significance. Heart rate and diastolic blood pressure remained unchanged during and after infusion, while systolic blood pressure increased by 10-15 mmHg during and after infusion. We conclude that a single 1-hour prenalterol infusion in patients with severe congestive heart failure induces an haemodynamic improvement associated with a reduction of previously elevated circulating NE levels. This reduction could indicate a lowering in the intensity of the afferent stimulus for the reflex sympathetic overactivity.
 ...
PMID:Acute effects of beta 1 agonism with prenalterol on catecholamine circulating levels in patients with congestive heart failure. 614 75


1 2 Next >>