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Shimizu W - - 1994
We report a patient with congenital long QT syndrome in whom early afterdepolarizations (EADs) were demonstrated on monophasic action potential (MAP) recordings in the left ventricular mid-base inferior wall. Epinephrine infusion at 5 micrograms/min increased the amplitude of the EADs and the late component of the T(U) wave. Epinephrine also ...
Noguchi K - - 1994
The effects of the active metabolite (18-502) of bopindolol, which is a new nonselective beta-adrenoceptor antagonist, were studied on the ischemic changes in myocardial segment shortening, cardiac lactate metabolism and S-T segment of subendocardial electrocardiogram during coronary stenosis and on their recoveries after reperfusion in anesthetized dogs, and were compared ...
De Cesare N - - 1994
BACKGROUND: Alpha-adrenergic activation enhances coronary vascular tone; beta-blockade leaves alpha-adrenergic vasoconstriction unopposed. Whether beta-adrenergic blockade facilitates coronary spasm in patients with Prinzmetal's angina is unknown. METHODS: Using quantitative angiography, we evaluated the response of normal and narrowed coronary arteries to intravenous propranolol, a cold pressor test (an alpha-stimulus), and the ...
Hashimoto H - - 1994
Previous studies showed that volatile anesthetics depressed ventricular delayed activation in a canine myocardial infarction model. It is well known that class I antiarrhythmic drugs depress the ventricular activation in the infarcted myocardium. In the present study, we examined the electrophysiologic interaction between volatile anesthetics (sevoflurane, isoflurane) and class I ...
Hashimoto H - - 1994
Previous studies have showed that halothane has depressed ventricular activation in a canine myocardial infarction model. It is also well known that class I antiarrhythmic drugs depress ventricular activation in the infarcted myocardium. In the present study, we examined whether some electrophysiologic interactions between halothane and two class I antiarrhythmic ...
Ditchey R V - - 1994
Epinephrine increases coronary blood flow but may not improve the balance between myocardial oxygen supply and demand during cardiopulmonary resuscitation (CPR). The objective of this study was to determine whether this balance can be improved by administering a relatively pure alpha-adrenergic vasoconstrictor, alone or in combination with a beta-adrenergic blocker. ...
Vanoli E - - 1994
INTRODUCTION: The primary goal of the present study was to test whether selective pharmacologic blockade of alpha 1 receptors, and specifically of the subtype alpha 1a, could prevent ventricular fibrillation (VF) during acute myocardial ischemia. BACKGROUND: The development of new autonomic interventions is of clinical interest in view of the ...
Hattingh P - - 1993
During coronary artery bypass graft (CABG) surgery, patients pretreated with the combination of beta-blocking drugs and Ca2+ antagonists for control of myocardial ischemia often respond inadequately to adrenergic stimulants administered after cardioplegic arrest. In this study, the effects of the combination of a beta-blocker (propranolol) and a Ca2+ antagonist (nifedipine) ...
Bertini G - - 1993
This study was designed to assess the effectiveness of early prehospital intravenous administration of lidocaine in preventing primary ventricular fibrillation (PVF) in patients with suspected acute myocardial infarction (AMI). Sixty patients with suspected AMI, seen by the Mobile Coronary Care Unit (MCCU) of Florence, were randomly allocated at home to ...
Juneja R - - 1993
Prophylactic lidocaine hydrochloride infusion followed by oral mexiletine hydrochloride was administered in the early post operative period to patients with poor left ventricular function undergoing coronary artery bypass graft surgery, to determine whether this decreased the incidence of ventricular arrhythmias and sudden death due to arrhythmias. Patients were randomly allocated ...
Kurose M - - 1993
The use of propranolol is generally contraindicated in patients with congestive heart failure. However, we successfully used a continuous high-dose infusion of propranolol, in combination with the use of extracorporeal life support (ECLS) and intra-aortic balloon pumping (IABP), to treat refractory life-threatening ventricular tachycardia in a patient with postoperative congestive ...
Gillis A M - - 1993
Little information is available currently regarding the time course of myocardial accumulation and the onset of the electrophysiologic effects of antiarrhythmic drugs in humans. The myocardial uptake and pharmacodynamics of the antiarrhythmic drug, procainamide, were studied during i.v. infusion in nine patients with ventricular tachycardia undergoing electrophysiologic study. Myocardial procainamide ...
De Ferrari G M - - 1993
OBJECTIVES: The goal of the present study was to evaluate the antifibrillatory and hemodynamic effects of pharmacologic muscarinic activation and to compare them with those of beta-adrenergic blockade. BACKGROUND: Recent studies suggest a correlation between increased vagal activity and a reduced incidence of sudden cardiac death. Electrical stimulation of the ...
Simaan J A - - 1993
The effect of pretreatment with phenytoin (diphenylhydantoin), lidocaine, and, for comparison, quinidine, on the doses of ouabain which produce a maximal inotropic effect, onset of arrhythmias and cardiac arrest, was explored in the cat heart-lung preparation. Ouabain was administered as an infusion (0.5 micrograms/min) either alone or after treatment with ...
Bagrov A Y - - 1993
OBJECTIVE: The aim was to study whether a circulating sodium pump inhibitor (endogenous digoxin-like factor) contributes to the genesis of early ventricular arrhythmias in acute myocardial ischaemia in rats. METHODS: Effects of digoxin antibody (260 micrograms.kg-1) on the incidence of ventricular arrhythmias, plasma digoxin-like immunoreactivity (DELFIA immunoassay), Na+, K+, and ...
Feuerstein G Z - - 1993
Carvedilol is a multiple action antihypertensive drug with potential use in angina and congestive heart failure. The pharmacological profile of carvedilol includes both beta-adrenoceptor blockade and vasodilation, the latter primarily a result of alpha 1-adrenoceptor blockade. Since many beta-blockers have cardioprotective properties, the present study was designed to determine whether ...
Johnson R G - - 1993
Life-threatening ventricular ectopy can occur after cardiac operations. The actual incidence of ventricular ectopy and the ability to prevent it by the routine prophylactic use of lidocaine hydrochloride have not been established. We performed a double-blind, randomized, prospective trial involving 109 patients undergoing elective coronary artery revascularization. Patients received either ...
Drake-Holland A J - - 1993
Following a 45-min period of coronary occlusion the myocardial infarct that developed after 24 h of blood reperfusion in the rabbit heart was studied in three groups of animals: controls (n = 7), and those pretreated with 3 mg.kg-1 of the piperazine derivative, trimetazidine (n = 7) or propranolol at ...
Schwinger R H - - 1993
The present study was aimed to characterize the effects of epinine, the metabolite of the p.o. active dopamine derivate ibopamine in human cardiovascular tissues such as myocardium, coronary artery and pulmonary artery. Isometric force of contraction was studied in electrically driven papillary muscle strips from nonfailing (brain death), moderately failing ...
Huang Y F - - 1993
Mass balance principles were used to study the myocardial pharmacokinetics of lignocaine in conscious sheep. After i.v. bolus doses of lignocaine 50, 75 or 100 mg, arterial lignocaine concentrations reached a peak in approximately 16 s and these increased linearly with dose. Coronary sinus concentrations reached a peak between 83 ...
Jaffe A S - - 1993
Antiarrhythmic agents have been used to treat malignant ventricular arrhythmias in the setting of acute myocardial ischemia with proven efficacy for many years. Thus, it has been presumed that these agents would be efficacious for the treatment of cardiac arrest. Unfortunately, hard data supporting this contention are unavailable to date. ...
Tanaka H - - 1993
1. The effects of beta-adrenoceptor blockade and reserpinization on the positive chronotropic and inotropic responses to lysophosphatidylcholine (LPC) were examined in isolated atrial and ventricular preparations from rat hearts. 2. The positive responses to 10(-4) M LPC were about 40-55% of those to 10(-5) M norepinephrine (NE) in each preparation. ...
Mangar D - - 1993
To determine the effects of pancuronium and vecuronium on heart rate, 90 patients scheduled for aortocoronary bypass were randomly assigned to one of three groups (30 patients each) which received vecuronium 100 micrograms[sdot]kg-1, pancuronium 100 micrograms[sdot]kg-1, or a mixture of vecuronium (50 micrograms[sdot]kg-1) and pancuronium (50 micrograms[dot]kg-1) in a double-blind ...
Kuzmin A I - - 1992
Using cardiac microdialysis, we studied release of the adenine nucleotide breakdown products (ANBP) adenosine (ADS), inosine (INS), and hypoxanthine (HYP) into the interstitium of canine myocardium during 20- and 40-min occlusion of the anterior descending coronary artery and reperfusion. Dialysate ANBP concentrations reached maximum values not at the end of ...
Berntsen R F - - 1992
The efficacy of lidocaine to prevent ventricular fibrillation during the prehospital phase of suspected acute myocardial infarction was assessed 3 hours after administration in a randomized controlled trial. A total of 204 patients examined within 6 hours after onset of symptoms were included, and acute myocardial infarction was later confirmed ...
Hashimoto H - - 1992
The effects of halothane on the effective refractory period (ERP) and the ventricular activation were examined in a canine myocardial infarction model, and compared with those of propranolol. Halothane reduced the heart rate and prolonged the ERP in both normal and infarcted zones. A prolongation of ERP with halothane was ...
Moller R A - - 1992
Bupivacaine-induced cardiotoxicity is enhanced in pregnant laboratory animals and in progesterone-pretreated isolated cardiac tissues. Ropivacaine is a new local anesthetic chemically related to bupivacaine. Although clinically equipotent with bupivacaine, ropivacaine is less cardiodepressant. Progesterone levels are elevated during pregnancy, and exogenously increasing progesterone levels in rabbits has increased bupivacaine's depressive ...
Ferrara N - - 1992
Twenty-one patients with angiographic evidence of significant coronary artery disease, and positive dipyridamole echocardiographic test results at basal condition and after 7 days of placebo treatment were prospectively studied to see whether beta blockade modifies the effects of dipyridamole echocardiographic testing on regional myocardial contractility. Patients were randomized to propranolol ...
Antman E M - - 1992
BACKGROUND: The purposes of the present investigation were 1) to track the incidence of primary ventricular fibrillation (VF) in the control and lidocaine-treated groups in the randomized control trials (RCTs) of lidocaine prophylaxis against primary VF in acute myocardial infarction, with particular emphasis on the time frame of the randomized ...
Wilson A C - - 1992
Survivors of myocardial infarction with less than 2 PVC/h on 24-h ambulatory electrocardiography were followed up for an average of 25 months (11 to 40 months) while receiving a placebo (1,222 patients) or propranolol, 180 or 240 mg/day (1,234 patients). Three quarters of the participants with PVCs had an average ...
Rong P - - 1992
After ligation of the left coronary artery in rats, myocardial norepinephrine (NE) and ATP depletions in both infarcted (IZ) and non-infarcted zone (NIZ) were studied. In IZ, the depletions of NE and ATP were biphasic and the depleting rate constants were found to be K1 = 0.71 h-1 and K2 ...
Abete P - - 1992
The effect of age on ventricular automaticity in the isolated perfused rat heart was determined under different conditions. When the ventricle is electrically stimulated at a faster rate, drive cessation is followed by a temporary suppression of ventricular automaticity (overdrive suppression). The effects of ischemia, lidocaine and verapamil on overdrive ...
Ellingsen O - - 1992
To determine whether the catecholamine-induced myocardial potassium uptake could be mimicked by increasing extracellular and intracellular calcium concentrations in vivo, we measured changes in myocardial potassium balance in nine anaesthetized open-chest pigs with PVC-valinomycin electrodes in arterial and coronary sinus blood. CaCl2 infusion (200-400 mumol min-1) into the left coronary ...
Hashimoto H - - 1992
Effects of flecainide, a class I antiarrhythmic drug, on ventricular arrhythmias, ventricular abnormal automaticity and ventricular activation were examined in a canine model of myocardial infarction, and compared with those of lidocaine. The effects of the drugs were examined on (1) the arrhythmias developed 24 h after the left anterior ...
Bril A - - 1992
The aim was to evaluate in a minipig model of acute myocardial infarction the cardioprotection provided by the beta adrenoceptor blocking and vasodilating activities present in carvedilol; comparison was made to the pure beta adrenoceptor antagonist, propranolol. Experiments were performed in 25 Yucatan minipigs (9-12 kg), randomly assigned to receive ...
Molinero E - - 1992
We compared the effect of verapamil slow-release (VSR) and the combination of nifedipine plus propranolol on transient myocardial ischemia in a double-blind study comprising 20 patients with proven coronary artery disease and chronic stable angina. According to the results of 24-h Holter-monitoring recording, patients were divided into two groups: 10 ...
Hashimoto H - - 1992
Effects of SUN-1165, a class I antiarrhythmic drug, on ventricular arrhythmias, intraventricular conduction, and the effective refractory period (ERP) were examined in a canine model of myocardial infarction and compared with those of lidocaine. The antiarrhythmic effects were examined on the arrhythmias developed 24 h after left anterior descending coronary ...
de la Coussaye J E - - 1992
A common property of all Class I antiarrhythmic agents is the inhibition of the fast inward current INa. Consequently, ventricular conduction velocities are impaired and reentrant phenomena are counteracted. Unfortunately, these conductive pathway disturbances may also induce proarrhythmic effects and reduce cardiac contractility. Recent evidence indicates that a cholinergic agonist, ...
Feuerstein G Z - - 1992
Carvedilol is a multiple-action cardiovascular agent that is both a beta-adrenoceptor antagonist and a vasodilator and has recently been made available for the treatment of mild-to-moderate hypertension. Clinical trials are ongoing to establish the efficacy of carvedilol in angina and congestive heart failure. beta-Adrenoceptor antagonists are known to reduce myocardial ...
Andreotti F - - 1991
The incidence of myocardial infarction and sudden cardiac death is highest in the morning. Inhibition of fibrinolytic activity in blood also peaks in the morning and this inhibition may favor the development of arterial thrombosis. It has been reported that patients treated with beta blockers do not show the typical ...
Wesley R C RC - - 1991
OBJECTIVE: Despite a history of widespread use, the utility of lidocaine as an antiarrhythmic and antifibrillatory agent is questionable. The objective of this article is to examine the theoretical basis for the use of lidocaine in light of recent experimental and clinical data. This article reviews the effects of lidocaine ...
Okita Y - - 1991
Postoperative intravascular hemolysis occurring in 2 patients was alleviated by propranolol. One patient underwent mitral valve replacement and had development of intractable hemolysis due to a paravalvular leak. The other patient underwent ventricular septal defect closure and had hemolysis caused by the Dacron patch. Both patients were given oral propranolol, ...
Bright J M - - 1991
The positive lusitropic and direct coronary vasodilating properties of the calcium channel blocking agents are beneficial therapeutic effects not provided by the beta-adrenergic blocking agents for the management of feline HCM. Data from cats studied at the University of Tennessee suggest that diltiazem more consistently alleviates clinical signs and more ...
Fujioka H - - 1991
The present study was undertaken to elucidate a possible role of non-beta-receptor mediated effects in dl-propranolol-induced enhancement of post-hypoxic contractile and metabolic recovery in perfused rat hearts. The rat hearts were perfused for 30 min under reoxygenated conditions following 15 min-substrate free-hypoxic perfusion, and the cardiac performance and myocardial metabolism ...
Weiner B - - 1991
Antidysrhythmic medications, when administered in the clinical setting, demonstrate a variety of effects on cardiac electrophysiology, inotropy, and peripheral vascular smooth muscle. The resultant hemodynamic effects may be of profound importance to the clinical well-being of the patient being treated for dysrhythmias. The following review will discuss the hemodynamic effects ...
Goldstein M - - 1991
Bisoprolol is a new cardioselective beta1 adrenergic blocking agent without intrinsic sympathomimetic activity but with minimal effects on myocardial contractility. Bisoprolol was compared to propranolol in 24 patients after cardiac surgery for coronary artery bypass graft (CABG). Each patient had been treated preoperatively with beta-blocking agents and had a cineangiographic ...
Li G R - - 1991
Transmembrane electrical activity was recorded from endo- and epicardium of isolated segments of guinea pig right ventricles with standard microelectrode techniques. An ECG was also recorded by two electrodes placed at opposite ends of the tissue bath. Regular stimulation was delivered to the endocardium. Tissues were exposed to simulated ischemia ...
Kumar K - - 1991
We conducted electrophysiologic (EP) studies and estimated the sinus node function and atrioventricular (AV) conduction in 10 patients with suspected coronary arterial disease (age range 35-55 years) before and during diltiazem therapy (60 mg thrice daily for 5-7 days). The effect of beta blockade (0.1 mg/kg of intravenous propranolol) was ...
Stanley J C - - 1991
Haemodynamic variables were measured following administration of pipecuronium 70 micrograms.kg-1 and pancuronium 90 micrograms.kg-1 (approximately equivalent to 1.5 x ED95) in patients anaesthetised with fentanyl 50 micrograms.kg-1 and scheduled to undergo coronary artery bypass grafting. There were significant increases in heart rate (22%), mean arterial pressure (10%), cardiac index (16%), ...
Busch A E - - 1991
Triamterene (CAS 396-01-0) and a series of benzyl-triamterene derivatives were evaluated for their antiarrhythmic properties in the coronary artery ligated and reperfused (CAL-R) rat. The effects were compared with the antiarrhythmic activity of the potassium sparing diuretic amiloride and drugs out of the class-I (lidocaine) and class-III (amiodarone and sotalol). ...
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