Acute haemodynamic and myocardial metabolic effects of intravenous urapidil in severe heart failure

Efficacy and Safety of Intravenous Urapidil for Older Hypertensive Patients with Acute Heart Failure: A Multicenter Randomized Controlled Trial

PURPOSE

Urapidil is putatively effective for patients with hypertension and acute heart failure, although randomized controlled trials thereon are lacking. We investigated the efficacy and safety of intravenous urapidil relative to that of nitroglycerin in older patients with hypertension and heart failure in a randomized controlled trial.

MATERIALS AND METHODS

Patients (>60 y) with hypertension and heart failure were randomly assigned to receive intravenous urapidil (n=89) or nitroglycerin (n=91) for 7 days. Hemodynamic parameters, cardiac function, and safety outcomes were compared.

RESULTS

Patients in the urapidil group had significantly lower mean systolic blood pressure (110.1±6.5 mm Hg) than those given nitroglycerin (126.4±8.1 mm Hg, p=0.022), without changes in heart rate. Urapidil was associated with improved cardiac function as reflected by lower N terminal-pro B type natriuretic peptide after 7 days (3311.4±546.1 ng/mL vs. 4879.1±325.7 ng/mL, p=0.027) and improved left ventricular ejection fraction (62.2±3.4% vs. 51.0±2.4%, p=0.032). Patients given urapidil had fewer associated adverse events, specifically headache (p=0.025) and tachycardia (p=0.004). The one-month rehospitalization and all-cause mortality rates were similar.

CONCLUSION

Intravenous administration of urapidil, compared with nitroglycerin, was associated with better control of blood pressure and preserved cardiac function, as well as fewer adverse events, for elderly patients with hypertension and acute heart failure.

Therapeutic effects of intravenous urapidil in elderly patients with hypertension and acute decompensated heart failure: A pilot clinical trial

Urapidil has been proposed to be an effective vasodilator for the treatment of acute decompensated heart failure (ADHF); however, its effect on cardiac function, as compared with that of nitroglycerin, in elderly patients with hypertension and ADHF has yet to be determined. In the present study, a multicenter, open-label clinical trial was performed, in which 120 elderly patients with hypertension and ADHF were randomly assigned to the treatment (50–400 µg/min intravenous urapidil) or control group (5–40 µg/min intravenous nitroglycerin). The dosages of the medications were adjusted according to the blood pressure of the patients. The systolic and diastolic blood pressure, heart rate and serum level of N-terminal pro B-type natriuretic peptide (NT-proBNP) were evaluated at hospital admission and at days 1, 2, 3 and 7 after treatment. In addition, the left ventricular function was assessed by measuring the left ventricular ejection fraction (LVEF) and left ventricular end-diastolic volume at hospital admission and at days 2 and 7 after treatment. The results indicated that intravenous administration of urapidil and nitroglycerin were effective in lowering the blood pressure and heart rate within 7 days, with no significant differences observed between the two groups (P>0.05). By contrast, greater reduction in the serum NT-proBNP level (2,410.4±546.1 vs. 4,234.1±876.4 pg/ml; P<0.05) and greater improvement in the LVEF (55.3±3.4 vs. 45.2±2.4%; P<0.05) were observed in the urapidil-treated group, as compared with the nitroglycerin-treated group. No adverse events were reported during the treatment period in the two groups. The clinical outcomes at 6 months following discharge were evaluated and were not found to be significantly different between the two groups. In conclusion, the present results of the present study suggested that urapidil was as effective as nitroglycerin in controlling blood pressure and heart rate and was more effective in improving cardiac systolic function in elderly patients with hypertension and ADHF.

Effects of nicardipine and urapidil on length-dependent regulation of myocardial function in coronary artery surgery patients

OBJECTIVE

To assess effects of a decrease in left ventricular (LV) afterload (pharmacologically induced by nicardipine and urapidil) on myocardial contraction and relaxation, with emphasis on the effects on load dependence of myocardial function.

DESIGN

Prospective, blinded study.

SETTING

University hospital.

PARTICIPANTS

Coronary artery surgery patients.

INTERVENTIONS

Alterations of systolic load were effected by leg elevation in control conditions and after administration of either nicardipine or urapidil before and after cardiopulmonary bypass.

MEASUREMENTS AND MAIN RESULTS

High-fidelity LV pressure tracings were obtained at end-expiration while hearts were paced at a fixed rate of 90 beats/min. Hemodynamic effects of leg elevation were compared before and after nicardipine, 7 microg/kg (n = 15), and before and after urapidil, 0.4 mg/kg (n = 15). The effects of leg elevation on parameters of contraction and relaxation were coupled. Both nicardipine and urapidil similarly decreased systolic pressures and peripheral resistance. Nicardipine decreased rate of pressure development (dP/dtmax) and slowed LV pressure fall, whereas load dependence of LV relaxation was not altered. Urapidil did not alter dP/dtmax, rate of LV pressure fall, or load dependence of relaxation. Similar results were observed after cardiopulmonary bypass.

CONCLUSIONS

The results of the present study indicate that a pharmacologically induced moderate reduction in LV afterload with nicardipine or urapidil did not alter the length-dependent regulation of myocardial function.

Intracoronary-administered urapidil does not influence myocardial contractility, metabolic activity, or coronary sinus blood flow in humans

OBJECTIVE

To compare the acute effect of intracoronary administration of urapidil and saline on myocardial contractility and metabolic activity.

DESIGN

Prospective, controlled, open-label study.

SETTING

University teaching hospital.

PARTICIPANTS AND INTERVENTIONS

Eight patients with stable coronary artery disease (CAD) undergoing elective percutaneous transluminal coronary angioplasty (PTCA) received normal saline followed by urapidil, 4 mg, injected directly into the left main coronary artery.

MEASUREMENTS AND MAIN RESULTS

Because local intracoronary administration is a non-steady-state condition, an in vitro model was used before the clinical experiments to establish the kinetic effects of acute administration of urapidil. The clinical experiments were performed in eight patients with CAD after PTCA. Measurements included a complete hemodynamic profile, coronary sinus blood flow (continuous thermodilution), left ventricular (LV) peak (+) dP/dt, LV peak (-) dP/dt, LV dP/dt/P(D)40, and LV end-diastolic pressures. Arterial and coronary venous blood samples were also obtained for the calculation of myocardial oxygen consumption. Baseline measurements I were first obtained, followed by intracoronary injection of 2 mL of saline. Additional measurements were obtained 1, 5, and 10 minutes after administration of saline. After a resting period (15 minutes), baseline measurements II, and intracoronary injection of urapidil, 4 mg (dissolved in 2 mL saline), additional measurements were obtained 1, 5, and 10 minutes later. Heart rate decreased 2.7+/-3.5 beats/min after injection of saline, whereas heart rate increased 2.0+/-1.8 beats/min after intracoronary urapidil, resulting in a significant difference in treatment effect (p = 0.003). There were no additional differences in treatment effect for any of the other measured or calculated parameters reflecting systemic hemodynamics, LV contractility, coronary dynamics, and myocardial metabolic activity.

CONCLUSION

The results suggest that intracoronary bolus administration of preservative-free urapidil, 4 mg, is not associated with any detectable effect on myocardial contractility or coronary smooth muscle in awake nonsurgical patients with CAD, after PTCA.

The nitura study--effect of nitroglycerin or urapidil on hemodynamic, metabolic and respiratory parameters in hypertensive patients with pulmonary edema

OBJECTIVE

To assess the effects of nitroglycerin or urapidil on hemodynamic, respiratory and metabolic parameters in hypertensive patients with pulmonary edema.

DESIGN

Open, randomized and prospective clinical study.

SETTING

Out-of-hospital setting and Emergency Department in a 2000-bed hospital.

PATIENTS

Hundred twelve patients with evidence of hypertensive crises with pulmonary edema (systolic blood pressure (SBP) > 200 mmHg and/or diastolic blood pressure (DBP) > 100 mm Hg and rales over both lungs) at the time when the emergency physician arrived.

INTERVENTIONS

The out-of-hospital treatment consisted of oxygen via face mask, 80 mg furosemide i.v., 10 mg morphium s.c., and either nitroglycerin sublingually (initial dose: 0.8 mg; repetitive administration of 0.8 mg every 10 min to a cumulative dose of 3.2 mg) or urapidil (initial dose: 12.5 mg i.v.; repetitive administration every 15 min to a cumulative dose of 50 mg). If SBP was more than 180 mm Hg and/or DBP more than 90 mm Hg on admission, antihypertensive treatment was continued with nitroglycerin (0.3-3 mg/h) or urapidil (5-50 mg/h).

MEASUREMENTS AND RESULTS

Blood pressure (BP) was measured every 5 min with the use of an automatic oscillometric device. Serum lactate, PO2, pH value, and base excess (BE) were evaluated on admission and 6 h later. Blood pressure, serum lactate and BE on admission were significantly lower (SBP: 155 +/- 30 vs 179 +/- 33 mm Hg; p = 0.0002; DBP: 82 +/- 17 vs 93 +/- 19 mmHg; p = 0.001; lactate: 2.2 +/- 1.6 vs 3.9 +/- 2.7; p = 0.0001; BE: -1.9 +/- 3.9 vs -4.4 +/- 1.7; p = 0.0005) and PO2 and pH values were significantly higher in the urapidil group compared to the nitroglycerin group (PO2: 75 +/- 25 vs 66 +/- 17; p = 0.036; pH: 7.33 +/- 0.08 vs 7.29 +/- 0.09; p = 0.042). After 6 h no differences between the two groups were observed.

CONCLUSION

The more pronounced BP reduction in the urapidil group was associated with an improved respiratory and metabolic situation in hypertensive patients with pulmonary edema. Therefore, urapidil is a valuable alternative to nitroglycerin in patients with pulmonary edema and systemic hypertension.

Course of blood pressure within the first 12 h of hypertensive urgencies

OBJECTIVE

To evaluate the course of blood pressure within 12 h of a hypertensive urgency with or without oral antihypertensive treatment prior to discharge of patients from hospital.

DESIGN

A prospective, double-blinded, placebo-controlled and randomized clinical trial.

SETTING

Department of Emergency Medicine in a 2000-bed inner city hospital.

PATIENTS

Forty patients successfully treated for a hypertensive urgency with intravenous administration of urapidil.

INTERVENTIONS

We administered 60 mg urapidil orally or placebo prior to discharge of patients from hospital and evaluated the course of blood pressure within 12 h of the urgency by use of an ambulatory blood pressure measurement unit.

MAIN OUTCOME MEASURES

Mean systolic and diastolic blood pressures within the first 12 h of a hypertensive urgency and the number of hypertensive and hypotensive episodes.

RESULTS

Mean systolic and diastolic blood pressures were significantly lower in members of the urapidil group than they were in members of the placebo group (132 +/- 14 versus 147 +/- 18 mmHg, P = 0.003; 79 +/- 12 versus 87 +/- 14 mmHg, P = 0.047, respectively). The number of hypotensive episodes was similar for these two groups (three versus one, P = 0.32), whereas the number of hypertensive episodes was significantly lower for the urapidil group (13 versus 34, P = 0.001).

CONCLUSIONS

Oral medication with urapidil prior to discharge results in lower overall blood pressure levels and reduces the risk of hypertensive episodes recurring within 12 h of a hypertensive urgency. Therefore, we recommend this therapeutic approach for patients with hypertensive urgencies, who are treated with an intravenous antihypertensive drug.

Blood pressure management during aortic surgery: urapidil compared to isosorbide dinitrate

The efficacy and hemodynamic effects of urapidil, an arteriolar vasodilator, and isosorbide dinitrate, a venodilator, were compared, when used for blood pressure control during abdominal aortic surgery. Urapidil is an alpha-adrenergic receptor antagonist with serotonin-1A receptor-agonist activity in the central nervous system. Hemodynamic profiles were recorded before and after the administration of the study drug (+/- 10 minutes before aortic clamping), 3 and 10 minutes following aortic clamping, and before and 3 and 10 minutes following the removal of the aortic clamp. Arterial and mixed venous oxygen contents were compared. Both groups of 18 patients were similar with respect to demographic profiles, anesthetic technique, and perioperative fluid therapy. Identical heart rate and blood pressure profiles were obtained. In contrast to isosorbide dinitrate, urapidil produced a 17% (P < 0.05) increase in cardiac index as a result of a 30% (P < 0.001) decrease in systemic vascular resistance before placement of the aortic clamp. In patients treated with urapidil, cardiac index was higher (P < 0.05) 10 minutes after aortic clamping, before removal of the clamp, and 10 minutes later. The arterio-venous oxygen content difference decreased from 3.2 +/- 0.8 mL O2/dL to 2.4 +/- 1.0 mL O2/dL (P < 0.01) following urapidil, but did not change during the administration of isosorbide dinitrate. It is concluded that urapidil is an effective and safe drug for the prevention of the hemodynamic consequences of aortic clamping. Compared to a venodilator (isosorbide dinitrate), urapidil offers the advantage of improving cardiac output and oxygen delivery.

Systemic and regional hemodynamic effects of alpha-adrenoceptor blockade in chronic left ventricular dysfunction in the conscious dog

In seven dogs with long-standing left ventricular dysfunction induced 16 weeks earlier by repetitive transmyocardial direct current (DC) shock, the acute hemodynamic effect of the alpha 1-adrenoceptor antagonist urapidil was studied. Left ventricular end-diastolic pressure (LVEDP) was significantly increased from preshock levels at the time of study and cardiac output was reduced. Plasma norepinephrine was significantly increased from control levels and was not altered by urapidil infusion. The mean arterial pressure fell in response to alpha 1-blockade from 111 to 85 mm Hg, the LVEDP fell from 16 to 9 mm Hg, and cardiac output increased from 2.90 to 3.70 L/min (all p less than 0.01). Regional blood flows measured by microsphere injection revealed an increase in blood flow to skeletal muscle, which had not been significantly decreased by the left ventricular dysfunction in this model, and further decreases in splanchnic flow, which was already depressed compared with that in normal dogs. Therefore acute alpha-adrenoceptor blockade improves central hemodynamics in experimental heart failure but does not normalize the resting blood flow maldistribution in this model.

Effect of urapidil on the performance of ischemic myocardium in anesthetized dogs

Urapidil (URA) is used to treat acute hypertension in patients with coronary artery disease, but the effect of URA on the performance of ischemic myocardium has not yet been investigated. The present study was intended to assess the function of ischemic myocardium following URA administration. In eight anesthetized (piritramide) open-chest dogs systolic contraction (dL) and end-diastolic length (edL) of myocardium supplied by the left descending (LAD) and circumflex (LCA) coronary arteries were measured by sonomicrometry simultaneously with aortic pressure (AoP), left ventricular end-diastolic pressure (LVedP), heart rate (HR), stroke volume (SV), and LAD-flow (QLAD). QLAD was reduced by LAD stenosis to about 50% of control, decreasing dLLAD by 55%. Concomitantly, edLLAD increased by about 9% and LVedP by 22%, whereas AoP decreased by 5%. Then, URA was given i.v. (0.25 + 0.25 + 0.50 + 1.0 mg/kg) in 15-min intervals. Following URA, the performance of the non-ischemic area was not systematically affected, but dLLAD increased by about 50%. This could neither be related to the significant reduction in afterload (AoP: -8%), nor to an increase in preload (LVedP and edLLAD did not change significantly), nor to an improved oxygen supply via the LAD (QLAD even decreased), although an increased collateral flow the LCA could not be excluded. The increase in systolic shortening correlated very closely to a decrease in heart rate (r = -0.92). It is concluded that the improved function of ischemic myocardium following urapidil resulted from a reduced oxygen demand in consequence to the decrease in heart rate.

Urapidil, a multiple-action alpha-blocking drug

Investigations in animals indicate that urapidil has a number of actions that may be relevant to its antihypertensive effect. It has an alpha 1-blocking action, a weak beta 1-blocking effect, an interaction with a serotonin receptor and a central depression of sympathetic tone. Urapidil is well absorbed orally with a bioavailability of about 70% and a time to peak concentration of about 4 hours after a sustained release capsule. It is metabolized in the liver at a half-life of 4.7 hours. Peripheral alpha 1-blocking activity has been demonstrated in humans. A shift to the right in the dose-response curve to phenylephrine has been found after urapidil, whereas responses to angiotensin are not affected. Evidence for beta 1-blocking activity is marginal. Urapidil does not inhibit the exercise increase in heart rate. Some investigators have suggested a possible inhibition of isoprenaline tachycardia; others have found no evidence. There is some evidence suggestive of a central action of urapidil in humans as lower single doses result in a decrease in blood pressure and an increase in heart rate. With higher doses the hypotensive effect continues but the tachycardia no longer occurs. However, urapidil has been reported to increase noradrenaline levels, although there has been a report with a high dose reducing vanillylmandelic acid excretion. Evidence for changes in renin is inconsistent. Hemodynamic studies have revealed findings that are compatible with peripheral alpha 1 blockade. After intravenous administration, peripheral resistance is reduced along with arterial pressure, and cardiac output is increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Overview of clinical trials with urapidil

Urapidil has been approved as sustained-release capsules containing 30, 60 and 90 mg, respectively, and as ampules containing 25 and 50 mg for treatment of all grades of hypertension, in several countries in Europe, South America, as well as in Japan and other Asian regions. In general, the treatment should start with 60 mg twice daily, 1 capsule in the morning and 1 in the evening. This schedule may be adapted according to the therapeutic needs. During the last few years, urapidil has been investigated extensively in comparison with several types of established antihypertensive drugs. Urapidil given orally has been tested in comparative trials against placebo, acebutolol, metoprolol, captopril, nifedipine and nitrendipine with responder rates of 40 to 70%. These responder rates are to be expected for a variety of antihypertensive drugs in monotherapy. Further studies with clonidine, prazosin and alpha-methyldopa showed similar responder rates as established for the other antihypertensive drugs studied. Adverse reactions include dizziness, headache and nausea and occasionally tiredness, orthostatic dysregulation and gastric disorders. These symptoms were transient, mostly occurring during the early phases of therapy and disappearing as treatment continued. Adverse effects are considered to be mainly due to blood pressure reduction. Intravenous comparative trials have been performed with urapidil against placebo, diazoxide and sodium nitroprusside. Adverse effects of parenterally applied urapidil are similar to those observed during oral treatment. Specific contraindications for urapidil are unknown. However, as for other vasodilating drugs, intravenous urapidil should not be administered to patients with stenosis of the aortic isthmus or with aortic valve insufficiency.

Urapidil-induced hemodynamic changes in humans

In hypertensive patients as well as in normal subjects urapidil has a hypotensive action. This is mainly mediated by a peripheral alpha 1-adrenoceptor blockade with a decrease in systemic vascular resistance; in addition, during acute animal experiments a centrally mediated hypotensive action was demonstrated, possibly by 5-hydroxytryptamine1A (5-HT1A)-receptor stimulation. Studies in humans showed an increase in cardiac output, which was not always significant; it did result either from an increased heart rate or an increased stroke volume. Acute changes in pulmonary hemodynamics after administration of urapidil were most pronounced in patients with pulmonary hypertension: pulmonary artery pressure and pulmonary vascular resistance decreased significantly and pulmonary capillary wedge pressure decreased nonsignificantly. A small reduction in pulmonary artery pressure and capillary wedge pressure were seen in patients with congestive heart failure and in patients in whom acute blood pressure elevation developed after coronary bypass surgery. In patients with essential hypertension forearm, renal and splanchnic flow were shown to increase and vascular resistance to decrease significantly after acute intravenous doses of urapidil. The hemodynamic changes during chronic therapy are largely unknown, except for systemic vascular resistance which remains decreased.

Acute blood pressure increase during the perioperative period

Hypertensive reactions occur frequently in the perioperative setting. Perioperative blood pressure elevation is generally amenable to treatment in previously normotensive patients. Alterations in cerebral autoregulation and myocardial performance in chronic hypertension limit the compensatory range available to cope with perioperative blood pressure changes. In cardiovascular or cerebrally compromised patients, the pathophysiology of underlying disease must therefore be taken into account. In the cerebrally compromised patient with space-occupying lesions and even merely locally impaired cerebral autoregulation, any blood pressure increase may reduce cerebral perfusion pressure and cause further cerebral impairment. Furthermore, vasodilation of cerebral vessels must be avoided to prevent further increase in intracranial pressure with reduction of cerebral perfusion. In chronically hypertensive patients, sufficient preoperative antihypertensive therapy is essential to avoid acute perioperative blood pressure elevation. Before antihypertensive pharmacologic therapy is begun, it is essential to rule out all correctable secondary causes of hypertension, particularly impairment of ventilation and oxygen supply. When pharmacologic antihypertensive therapy is necessary, vasodilators (e.g., calcium entry blockers) may be administered to chronically hypertensive patients. If elevated intracranial pressure is the underlying cause of hypertension, cerebral vasodilation must be avoided and only centrally acting antihypertensive agents such as urapidil should be used for management.

Effects of vasodilators on the coronary circulation in congestive heart failure

Pressure or volume overload of the myocardium increases the wall stress, particularly of the subendocardium, and leads to hypertrophy. Even though cardiac hypertrophy is viewed as a beneficial compensatory process that normalizes wall stress, the increased muscle mass carries with it the need of increased blood supply. Overall flow per unit mass is similar at rest in hypertrophic and normal hearts but a reduction of flow to the subendocardium and an increase in minimal coronary vascular resistance have been described. Thus, the potential exists for a vasodilator-induced steal mechanism shunting blood away from potentially ischemic areas. Angiotensin-converting enzyme inhibitors reduced myocardial oxygen consumption and coronary blood flow in parallel manner in some studies, indicating preserved coronary autoregulation, but there is also some evidence of a coronary vasodilator effect. Calcium antagonists reduce coronary vascular resistance and improve the myocardial demand-supply ratio, but the clinical usefulness of the newer compounds with supposedly little or no negative inotropic effects remains to be established. Hydralazine improved the myocardial oxygen demand-supply ratio in patients with dilated cardiomyopathy, but metabolic function may deteriorate more often after hydralazine than after angiotensin-converting enzyme inhibitors in patients with coronary heart disease. Similar observations have been made using alpha-adrenergic blockers. Although progress has been made in the understanding of the coronary circulation and the influence of vasodilators in congestive heart failure, many questions await clarification using refined or new methodology.

Acute haemodynamic effects of urapidil in patients with chronic left ventricular failure

Urapidil, a new alpha 1-adrenoceptor blocking drug, has been shown to be effective in the treatment of hypertension. Ten normotensive patients with severe congestive heart failure were given Urapidil 25 mg i.v. twice in 15 min and the haemodynamic effects were measured. There was a significant fall in systolic blood pressure (-16%), mean blood pressure (-13%), left ventricular end-diastolic pressure (-38%), mean pulmonary artery pressure (-31%) and wedge pressure (-40%). Total peripheral resistance fell by 25%, whereas pulmonary arteriolar resistance did not change significantly. Cardiac output increased by 22%. The increase in cardiac output with decreasing peripheral resistance and LV pressures suggests that urapidil may be useful in the therapy of congestive heart failure.

The assessment of the beta-blocking activity of urapidil: a new method

Urapidil is an antihypertensive vasodilator agent whose pharmacological action in man has not yet been fully defined. We have assessed the beta blocking activity of urapidil 15 mg and 30 mg i.v. in a single blind study of 10 healthy male volunteers. Urapidil at plasma concentrations in the same range as those shown to have antihypertensive affect did not significantly attenuate the chronotropic effect of isoproterenol. Propranolol 5 mg iv, the positive control, significantly shifted the isoproterenol dose-response curve to the right. We describe a new method of analyzing incomplete dose response curves whereby a linear terminal segment can be reproducibly defined.