Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of slow-release gallopamil (100 mg b.i.d.) were studied on exercise-induced ST-segment depression as well as on spontaneous myocardial ischemia detected by long-term electrocardiography (ECG) monitoring for 48 h in 26 patients with coronary artery disease and angina pectoris. Eight patients had to be excluded (because of paroxysmal atrial fibrillation in four patients, development of unstable angina pectoris in three patients, and frequent ventricular premature beats in one patient). In the remaining 18 patients, gallopamil led to an increase of work load (W x min) evaluated by bicycle ergometry, paralleled by an increase of exercise duration until the occurrence of ST-segment depression of > or = 0.1 mV in the nonblinded part of the trial. The number of spontaneous episodes of myocardial ischemia during long-term ECG recording, ranging from 0 to 14 during control, decreased in patients with two or more episodes during control, paralleled by a decrease in the total duration of ischemic episodes and a decrease in the ischemic score (duration of episodes x maximal ST-segment depression). During long-term ECG monitoring, we observed asymptomatic episodes of spontaneous second degree atrioventricular block of the Wenckebach type in three patients. No other adverse effects of slow-release gallopamil were observed. Therefore, these preliminary results of the non-blinded protocol confirm the anti-ischemic effects of slow-release gallopamil given 100 mg b.i.d.; however, these promising results will have to be confirmed in the consecutive double-blind, placebo-controlled part of the trial.
J Cardiovasc Pharmacol 1992
PMID:Slow-release gallopamil evaluated by exercise test and long-term electrocardiography. 128 62

The anti-ischemic properties and tolerability of a slow-release formulation (SR) of gallopamil were investigated in 118 patients with exercise-inducible ST-segment depression and stable angina pectoris in this double-blind, randomized, placebo-controlled, multicenter study. After a placebo run-in period (A) of 2-7 days and a 7-day open therapy period (B) with gallopamil SR, the patients were randomized to a double-blind 7-day period (C) to receive placebo or gallopamil SR 100 mg twice a day. Each patient was submitted to gradual upright bicycle ergometry and electrocardiography (ECG) at rest on the last 2 days of each period at 6 and 12 h postadministration (p.a.) In period C, exercise time and exercise tolerance remained significantly prolonged at 6 and 12 h after gallopamil SR administration in comparison with the placebo values. Additionally the sum of ST-segment depression and maximal ST-segment depression were significantly reduced by gallopamil SR at 6 h p.a. as were the frequency of angina attacks and nitroglycerin consumption. Four patients were withdrawn from the study because of gallopamil-related adverse events, which, however, were not serious. Constipation was noted in 2.5% of the patients. These data suggest that gallopamil SR is effective in reducing exercise-inducible ST-segment depression and increasing exercise tolerance with no serious adverse effects in patients with stable angina pectoris.
J Cardiovasc Pharmacol 1992
PMID:Efficacy and tolerability of slow-release gallopamil in patients with stable exercise-inducible angina pectoris. 128 63

To investigate retrograde delivery of cardioplegic solutions as a means of enhancing myocardial protection in the presence of coronary artery occlusion, a two-part experimental model was devised. In part 1 (in vitro) the possibility of retroperfusing the entire myocardium during acute occlusion of the left anterior descending artery (LAD) was assessed. In part 2 (in vivo) acute LAD occlusion was performed in dogs, and during 2 hours of aortic cross-clamping crystalline cardioplegic solution was infused at 20-minute intervals. In group I the infusion was antegrade, via the aortic root, and in group II it was retrograde, via the coronary sinus. Thereafter the LAD snare was released and the dogs were weaned from bypass. Delivery of cardioplegia through the aortic root was associated with depression of ventricular function, poor myocardial cooling and severe cellular damage. With the retrograde procedure there was significantly improved recovery of left ventricular function, uniform myocardial cooling and better preservation of cellular morphology.
Scand J Thorac Cardiovasc Surg 1992
PMID:Myocardial protection by retrograde cardioplegic perfusion in the presence of acute coronary artery obstruction. An experimental study. 128 35

Recent investigations of SMI occurring during daily life have advanced our understanding of the pathophysiology of myocardial ischemia. These contributions have directed our attention away from "chest pain" alone and physical exertion as the central provoking factor toward transient myocardial ischemia and its broader triggers and consequences. Transient myocardial ischemic episodes, the majority of which are silent, are found in a subset of patients with any clinical manifestations of CAD (eg, stable angina, unstable angina, myocardial infarction, and sudden death), as well as in those patients with CAD who are and have been totally asymptomatic. These episodes are an independent predictor of increased risk for future cardiac events. Most medical therapy and revascularization therapies have the potential to prevent or relieve these silent episodes; however, we do not yet know which method is superior in reducing SMI episodes or preventing future cardiac events. Furthermore, the benefit of reducing SMI versus the cost and potential morbidity of these chosen therapies is not known. At least three trials are now underway to examine some of these concerns (Table 2). Focus on pain relief alone does not appear to be an adequate approach to alter outcome in patients with CAD and may prove insufficient to control SMI. Until these issues are resolved, we believe a conservative approach to the management of patients with CAD is warranted. Documentation of ischemia (painful or painless) is essential. Three general principles should be kept in mind. First, the presence of detectable ischemia is of central importance. This information should be used in the overall risk assessment of the patient. Second, the level of concern or aggressiveness of treatment should be based on the risk associated with the ischemic abnormalities documented (Table 3). The exercise stress test is the most useful to begin this process. The detection of ischemic-type ST-segment depression, either silent or painful, at a low workload (eg, less than or equal to 120 beats per minute or less than or equal to 6.5 metabolic equivalents [METS]) implies high risk for adverse outcome. Likewise, these ST-segment changes occurring in leads that reflect multiple coronary artery distribution, of greater than 2 mm in magnitude and persisting for greater than 6 minutes, are all markers for high risk. Thallium redistribution defects occurring at low work loads, in multiple areas, associated with increased lung uptake and enlargement of the cardiac pool all imply high risk.(ABSTRACT TRUNCATED AT 400 WORDS)
Prog Cardiovasc Dis
PMID:Treatment strategies for daily life silent myocardial ischemia: a correlation with potential pathogenic mechanisms. 135 7

A number of studies have addressed the response to calcium antagonists, used alone or combined with other therapy, in patients with silent myocardial ischemia (SMI). Nifedipine, the first calcium antagonist to be studied, was shown to be superior to pindolol in patients with effort angina. Although both nifedipine and diltiazem significantly reduced episodes of ST depression, compared with placebo, in patients with stable effort angina, the addition of nifedipine to diltiazem removed the beneficial effect of diltiazem in another study. Studies have shown a reduced incidence of ischemic episodes during nicardipine treatment in patients with ambulatory ischemia, predominantly SMI, and rest angina due to coronary artery spasm. Other workers similarly reported that verapamil was superior to both placebo and propranolol in reducing painful and painless ischemia in patients with angina at rest. It has been demonstrated that, compared with placebo, nifedipine reduced ischemic episodes by 50% and also markedly reduced total ischemic time in totally asymptomatic men with coronary artery disease and SMI. It was suggested that the well-documented increase in SMI occurring between 0600 and 1200 h was reduced, but not eliminated, by nifedipine. Diltiazem may also attenuate the circadian variation in SMI. Nifedipine has been shown to be particularly effective in SMI when combined with a beta-blocker. This has been substantiated in a large group of patients; both drugs reduced the number of episodes of SMI when used as monotherapy, and the combination decreased the incidence by 95%. These findings collectively indicate that calcium antagonists are effective in reducing or preventing SMI.(ABSTRACT TRUNCATED AT 250 WORDS)
J Cardiovasc Pharmacol 1990
PMID:Clinical effects of calcium antagonists in silent ischemia. 136 8

We evaluated the effects of a single oral dose of 5 mg of isradipine compared to placebo in a randomized, double-blind, crossover study using gated radionuclide angiography at rest and during exercise in 20 patients with stable chronic angina. Isradipine improved both anginal symptomatology and ST-segment depression during exercise, with a concomitant favorable effect on the isotopic parameters exploring systolic and diastolic left ventricular function. There was a marked increase of the ejection fraction during exercise with isradipine compared to placebo (61 +/- 14% vs. 55 +/- 15%, respectively, p less than 0.001) as well as a significant improvement in the peak ejection rate and the peak filling rate at rest [2.56 +/- 0.62 vs. 2.16 +/- 0.54 end diastolic volume (EDV) per second and 2.14 +/- 0.59 vs. 1.87 +/- 0.37 EDV/s, respectively] and during exercise (3.49 +/- 0.97 vs. 3.10 +/- 1.07 EDV/s and 4.05 +/- 1.34 vs. 3.65 +/- 1.25 EDV/s, respectively). We conclude that isradipine has a beneficial effect on the clinical and electrocardiographic signs of exercise-induced ischemia, leading to a significant improvement of the systolic and diastolic parameters of left ventricular function. Therefore, isradipine is potentially a useful treatment for patients with exertional angina and hypertension, alone or associated with beta blocker medication.
J Cardiovasc Pharmacol 1992 Jan
PMID:Effects of oral isradipine on left ventricular function at rest and during exercise in patients with stable chronic angina: a double-blind, placebo-controlled crossover study. 137 79

The effects of synthetic endothelin on the coronary circulation were studied in pentobarbital-anesthetized dogs and compared with those of Bay k 8644, a dihydropyridine calcium channel agonist, and U 46619, a thromboxane analogue. Intracoronary bolus administration of endothelin reduced coronary blood flow and increased coronary arterial resistance. Similarly, intracoronary bolus administration of equipotent doses of Bay k 8644 or U 46619 significantly reduced coronary blood flow and increased coronary arterial resistance. The coronary vasoconstrictor effects of endothelin were long-lasting as compared with the transient actions of Bay k 8644 and U 46619. Intracoronary bolus injection of endothelin also reduced left ventricular (LV) dP/dt arterial pressure (MAP), and cardiac output (CO). In contrast, Bay k 8644 increased LVdP/dt but did not alter CO or MAP. Intracoronary bolus injection of U 46619 did not affect MAP, CO, or LVdP/dt. In a separate group of animals, intracoronary infusion of nitrendipine significantly increased coronary blood flow and reduced coronary arterial resistance. Other cardiovascular parameters measured were not significantly altered. In the presence of nitrendipine, the effects of intracoronary administration of endothelin and U 46619 on coronary blood flow, coronary arterial resistance, and LVdP/dt were only partially antagonized. On the other hand, the effects of Bay k 8644 were completely prevented in the presence of nitrendipine. These studies show that at doses which reduce coronary blood flow to the same extent, only endothelin produces myocardial depression in anesthetized dogs. The cardiovascular actions of endothelin were only partially antagonized by nitrendipine, suggesting that mechanisms other than calcium influx through voltage-operated channels are involved.
J Cardiovasc Pharmacol 1992 Feb
PMID:Effects of intracoronary administration of endothelin in anesthetized dogs: comparison with Bay k 8644 and U 46619. 137 88

The electrophysiologic and antiarrhythmic effects of ibutilide, sotalol, and encainide were compared in dogs 24 h after myocardial infarction. Ibutilide (0.03 to 0.3 mg/kg i.v.) prevented the induction of ventricular arrhythmias in 100% of the dogs that had demonstrated inducible ventricular arrhythmias prior to treatment. This antiarrhythmic action was associated with significant increases in ventricular refractoriness and monophasic action potential duration. Sotalol (1.0 to 10.0 mg/kg i.v.) increased the ventricular refractory period and monophasic action potential duration and prevented the induction of ventricular arrhythmias in 75% of the dogs that demonstrated inducible ventricular tachyarrhythmias at baseline. Although 10 mg/kg of sotalol was required to prevent the initiation of ventricular tachycardia, this dose produced marked cardiovascular depression and hypotension in 50% of the dogs tested. Neither ibutilide nor sotalol significantly decreased the incidence of spontaneous ventricular arrhythmias. The class IC agent encainide (0.3 to 3.0 mg/kg i.v.) was successful in preventing the induction of ventricular arrhythmias in only 20% of the dogs tested. However, in contrast to ibutilide and sotalol, encainide significantly reduced spontaneous arrhythmias. Atrial and ventricular refractoriness were significantly increased only after the highest dose of encainide tested (3.0 mg/kg). Over the dose ranges studied, the relative efficacy for prevention of pacing-induced ventricular arrhythmias was ibutilide greater than sotalol much greater than encainide. For suppression of spontaneous ventricular arrhythmias, the relative efficacy was encainide much greater than ibutilide = sotalol.(ABSTRACT TRUNCATED AT 250 WORDS)
J Cardiovasc Pharmacol 1992 Feb
PMID:Effects of ibutilide on spontaneous and induced ventricular arrhythmias in 24-hour canine myocardial infarction: a comparative study with sotalol and encainide. 137 95

To evaluate whether the hydroxylated metabolites of quinidine (Q) and hydroquinidine (HQ): hydroxy-3S-quinidine (OH-Q) and hydroxy-3S-hydroquinidine (OH-HQ), exert electrophysiologic effects and participate in the therapeutic action of the parent drugs, we examined and compared the effects of the metabolites and the parent drugs on the electrical activity of guinea pig ventricular cells recorded by standard microelectrode technique. In addition, we investigated the potential arrhythmogenic properties of these compounds in rabbit Purkinje fibers in low K+ (2.7 mM) Tyrode's solution. The concentration [C]-, frequency-, and voltage-dependent effects of the drugs were investigated. Maximum upstroke velocity of phase 0 (Vmax) was [C]-dependently depressed by both OH-Q and OH-HQ but at a lesser degree than with Q and HQ, respectively: at the [C] of 50 microM, Vmax depression attained 26.7 +/- 2.6% with OH-Q versus 45.9 +/- 1.6% with Q and 32.3 +/- 1.9% with OH-HQ versus 54.6 +/- 1.4% with HQ. This effect was frequency and voltage dependent without significant differences between the four compounds. In the presence of equipotent [C], recovery kinetics of Vmax was significantly slower with metabolites than with respective parent drugs. In contrast, the effects of metabolites on action potential duration at 90% of repolarization (APD90) and effective refractory period (ERP) differed from those observed with parent drugs. With metabolites, APD90 and ERP were increased in a [C]-dependent manner, whereas the Q- and HQ-induced lengthening in APD90 and ERP was observed only at low concentration and low frequency. In addition, the OH-Q- and OH-HQ-induced APD90 lengthening was not altered by increasing pacing rate. In rabbit Purkinje fibers, increase in cycle length and prolonged exposure to either metabolites or parent drug caused early afterdepolarizations (EADs) and triggered activity. With all drugs tested, EADs arose more frequently at the plateau level than at the final repolarization of AP, but the incidence of EADs appeared to be much lower with metabolites than with parent drugs. The present results demonstrate that OH-Q and OH-HQ exert qualitatively similar but quantitatively less potent depressant effects on Vmax than Q and HQ, respectively, but differ in the lengthening effect on APD. We suggest that metabolites may participate in class I antiarrhythmic action of their respective parent drug and contribute to their arrhythmogenicity.
J Cardiovasc Pharmacol 1992 Mar
PMID:Comparative electrophysiologic effects of metabolites of quinidine and hydroquinidine. 137 7

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 artery (LAD) ligation and ventricular premature stimulation-induced arrhythmias 5-7 days after LAD ligation. Effects on intraventricular conduction and ERP were also examined in animals 5-7 days after LAD ligation. The intraventricular conduction time (CT) was determined by excitation induced by a ventricular stimulation at various coupling intervals from 200 to 1,000 ms. SUN-1165 (1 and 3 mg/kg) showed a marked reduction in the frequency of ventricular ectopic beats 24 h after LAD ligation and was more potent than lidocaine. SUN-1165 (1 and 3 mg/kg) prolonged CT in the infarcted zones over a wide range of the coupling intervals and produced block of severely delayed conduction. In contrast, lidocaine prolonged CT only at short coupling intervals. Ventricular premature stimulation produced ventricular arrhythmias, which were prevented by pretreatment with SUN-1165 (3 mg/kg). ERP was prolonged by SUN-1165 (3 mg/kg). In conclusion, SUN-1165 showed antiarrhythmic effects in a canine model of myocardial infarction. A selective depression of delayed conduction in the infarcted zone and a prolongation of ERP probably contribute to this antiarrhythmic effect.
J Cardiovasc Pharmacol 1992 Mar
PMID:Effects of SUN-1165, N-(2,6-dimethylphenyl)-8-pyrrolizidine acetamide hydrochloride hemihydrate, a new class I antiarrhythmic drug, on ventricular arrhythmias, intraventricular conduction, and the refractory period in canine myocardial infarction. 137 23


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