Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adenosine, an endogenous nucleoside has been recently approved for use in the treatment of paroxysmal supraventricular tachycardia. Adenosine is nearly 100% effective in terminating tachycardia in which the atrioventricular node forms part of the reentrant circuit. Although most ventricular tachycardias are insensitive to adenosine, this substance is effective in ventricular tachycardia induced by catecholamines or exercise. An intravenous bolus dose of 6 mg is the initial dose. If no effect is noted a further bolus of 12 mg can be given. The most common side effects are dyspnea, chest pressure and facial flushing. This article reviews, in addition, some of the comparative trials with verapamil and adenosine triphosphate, some of the additional therapeutic indications, the possible mechanisms of action in cardiac tissue, and the type of purinergic receptors involved in the antiarrhythmic effects of adenosine.
 ...
PMID:Adenosine as a therapeutic agent. 145 18

Adenosine has recently become widely available for the treatment of paroxysmal supraventricular tachycardia. In order to evaluate its role in the management of arrhythmias, we have reviewed the literature on the cellular mechanisms, metabolism, potential for adverse effects, and clinical experience of the efficacy and safety of intravenous adenosine. Adenosine produces transient atrioventricular nodal block when injected as an intravenous bolus. This is of therapeutic value in the conversion to sinus rhythm of the majority of paroxysmal supraventricular tachycardias, which involve the atrioventricular node in a re-entrant circuit. The mean success rate was 93% from over 600 reported episodes. Compared with other antiarrhythmic agents, adenosine is remarkable for its rapid metabolism and brevity of action, with a half-life of a few seconds. It commonly produces subjective symptoms, particularly chest discomfort, dyspnea, and flushing, which are of short duration only. No serious adverse effect has been reported. Arrhythmias may recur within minutes in a minority of patients. Comparative studies have shown that adenosine is as effective as verapamil in the treatment of supraventricular tachycardia, and has less potential for adverse effects. Patients with supraventricular tachycardia should initially be treated using vagotonic physical maneuvers. Immediate electrical cardioversion is indicated if the arrhythmia is associated with hemodynamic collapse. Adenosine is the preferred drug in those patients in whom verapamil has failed or may cause adverse effects, such as those with heart failure or wide-complex tachycardia. The safety profile of adenosine suggests that it should be the drug of first choice for the treatment of supraventricular tachycardia, but only limited comparative data to support this view are available at present.
 ...
PMID:Adenosine and the treatment of supraventricular tachycardia. 160 47

Adenosine (adenine riboside), administered either as the free base or as the 5'-triphosphate (ATP) by rapid intravenous bolus, depresses atrioventricular (AV) nodal conduction, resulting in transient AV block. Adenosine is the active agent and ATP is rapidly converted to adenosine after exogenous administration. By blocking the anterograde AV nodal limb of a re-entrant circuit, adenosine 6 to 12 mg (or ATP 10 to 20 mg) converts almost all episodes of paroxysmal supraventricular tachycardia (PSVT) involving the AV node within 30 seconds of administration. This is at least equivalent in efficacy to verapamil in adults, and superior to lanatoside C in children, with a considerably more rapid onset of action. Furthermore, if a dose of adenosine is ineffective, the exceptionally short plasma half-life of the adenyl nucleosides (less than 10 sec) allows rapid upward dosage titration until PSVT is terminated. Because the induced conduction block primarily affects the AV node, adenosine is a useful diagnostic tool in patients with broad or narrow QRS complex tachycardia; it terminates arrhythmias dependent on the AV node, unmasks other supraventricular mechanisms during transient AV block, but almost always has no effect on ventricular tachycardia. Noncardiac adverse effects, i.e. flushing, dyspnoea and chest pain, may occur during acute arrhythmia termination or diagnosis with adenosine, and arrhythmias may develop; however, these effects are usually transient (lasting less than 1 minute). Adenosine has also been used to induce coronary vasodilation in patients undergoing thallium-201 single photon emission computed tomography (201Tl SPECT), 2-dimensional echocardiography or positron emission tomography to evaluate suspected coronary artery disease. Intravenous infusion of adenosine 140 micrograms/kg/min for 6 minutes was generally associated with only mild adverse effects. These usually resolved within 1 to 2 minutes of discontinuing adenosine, although occasionally patients required aminophylline and/or nitroglycerin (glyceryl trinitrate). Diagnoses based on the results of scintigraphy were of a sensitivity, specificity and predictive accuracy comparable to those achieved with exercise- or dipyridamole-201Tl SPECT. Adenosine is therefore particularly suitable for the diagnosis of tachycardias and the acute management of PSVT involving the AV node in all age groups, without the risks of cardiac arrest and hypotension associated with verapamil. Furthermore, intravenous adenosine infusion may be used to induce coronary vasodilation in patients unable to perform exercise stress tests for 201Tl scintigraphy, and is well tolerated.
 ...
PMID:Adenosine. An evaluation of its use in cardiac diagnostic procedures, and in the treatment of paroxysmal supraventricular tachycardia. 171 62

Previous studies have demonstrated the efficacy of bepridil, a new calcium antagonist, in the treatment of ventricular extrasystoles and tachycardia. The electrophysiological properties of bepridil especially the lengthening of the atrial effective refractory period, would also suggest an antiarrhythmic effect at the supraventricular level. This effect was studied on 33 episodes of paroxysmal supraventricular tachycardia (SVT) occurring in 23 patients (6 men and 17 women, mean age 58.1 years; range 18 to 88 years). Bepridil was given intravenously over 5 minutes at a dose of 3 mg/kg. The duration of SVT before administration was less than 1 hour in 10 cases, between 1 and 2 hours in 8 cases and over 2 hours in 15 cases. Sinus rhythm was successfully restored in 25 cases: within 1 to 5 minutes in 19 cases, 6 to 10 minutes in 3 cases and 11 to 30 minutes in 3 cases. In 24 of the 25 cases sinus rhythm was restored without a prolonged pause (over 2 sec) after the termination of SVT; in 3 cases intermediary atrial fibrillation lasting 1, 3 and 9 minutes was observed. There were no side-effects in 26 cases; transient flushing was noted in 5 cases and vagal symptoms in 2 cases. Haemodynamic tolerance judged by blood pressure measurements excellent in all cases. The correlations between plasma concentrations of bepridil and success or failure were poor. In conclusion, bepridil is a valuable alternative to adenosine triphosphate which may induce an exaggerated vagal response and to verapamil whose negative inotropic effects may sometimes be a serious disadvantage in the reduction of paroxysmal SVT.
 ...
PMID:[Bepridil in the treatment of supraventricular paroxysmal tachycardias]. 393 62

The efficacy and electrophysiologic effects of adenosine and verapamil in termination of paroxysmal supraventricular tachycardia (SVT) were compared in 18 patients (age 18-48 years, mean 33 +/- 9 years) with recurrent sustained and inducible SVT. Ten patients had atrioventricular nodal reentrant tachycardia (AVNRT) and 8 had atrioventricular reentrant tachycardia involving a retrograde accessory pathway (cycle length of SVT 280-360 msec; mean 315 +/- 20 msec). Each patient served as his own control. After induction of SVT, adenosine was administered first (6 mg i.v. bolus). If the tachycardia was not terminated, a bolus of 12 mg was given. Ten minutes later, verapamil (5 mg i.v. over 30 sec) was administered after reinduction of SVT. If the tachycardia was not terminated, a 5 mg dose was repeated every 5 minutes upto 20 mg. Adenosine terminated the SVT in 16 cases (6 mg - 7 patients, 12 mg - 9 patients). Verapamil was effective in 11 patients (5 mg - 6 patients, 10 mg - 4 patients, 15 mg - 1 patient, 20 mg - nil). The overall efficacy of adenosine (89%) was significantly greater than that of verapamil (61%; p < 0.05). Adenosine terminated the tachycardia more quickly than verapamil (mean 24 +/- 11 sec versus 142 +/- 40 sec; p < 0.01). Termination of tachycardia by both drugs was related to antegrade block of the atrioventricular node in all patients except one with AVNRT in whom adenosine blocked the retrograde fast pathway. Ventricular premature beats were seen transiently in 5 patients following adenosine. Transient side effects such as flushing, burning and chest pain were frequently observed with adenosine and correlated with the termination of tachycardia.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Comparative clinical and electrophysiologic effects of adenosine and verapamil on termination of paroxysmal supraventricular tachycardia. 782 34

Adenosine (Adenocard) is an endogenous purine nucleoside that has been approved recently for intravenous treatment of paroxysmal supraventricular tachycardia. With a serum half-life of 10 seconds, reported side effects including facial flushing, dyspnea, and chest pressure are common, but very transient. An elderly woman who received adenosine for paroxysmal supraventricular tachycardia had a prolonged anaphylactoid reaction that required pharmacological treatment. This is the first reported case of a prolonged anaphylactoid reaction to adenosine.
 ...
PMID:Anaphylactoid reaction to adenosine. 1015 40

Adenosine with its rapid onset and brief duration of action has a number of clinical applications including treatment of paroxysmal supraventricular tachycardia and maximal coronary vasodilatation during pharmacologic stress testing. The adverse effects of adenosine include dyspnea, nausea, headache, chest pain, flushing and bronchospasam. Although there were few reports which mentioned the occurrence of bronchospam after administration of adenosine, a number of studies indicated that the use of adenosine was not contraindicated in patients with chronic obstructive pulmonary disease (COPD) or asthma. We report here a male patient with pulmonary emphysema and lung bullous disease who developed severe constriction of the main bronchi after intravenous adenosine during general anesthesia. After treatment, the patient was discharged without complications. We have reviewed the related current literature and herein discuss the reason and management of the adenosine induced bronchospasm.
 ...
PMID:Intraoperative bronchospasm after intravenous adenosine during general anesthesia. 1567 35

Tecadenoson is a novel selective A1 adenosine receptor agonist that is currently being evaluated for the conversion of paroxysmal supraventricular tachycardia (PSVT) to sinus rhythm. By selectively targeting the A1 receptor, tecadenoson may be associated with fewer adverse effects such as flushing, dyspnea, chest discomfort, and hypotension than adenosine, which is a nonselective agonist of all 4 adenosine receptors. Based on the results of phase I and phase II clinical trials, tecadenoson appears to be an effective agent for producing rapid and sustained conversion of PSVT to sinus rhythm. Additionally, the adverse effects that are typically attributed to adenosine's nonselective stimulation of the A2A, A2B, and A3 receptors appear to occur less frequently with the use of tecadenoson. Tecadenoson also appears to be associated with a lower incidence of atrial fibrillation following conversion of PSVT compared with the rates that have been associated with adenosine in the literature. A randomized, prospective trial will need to be conducted in the future to appropriately compare the safety and efficacy of tecadenoson and adenosine.
 ...
PMID:Tecadenoson: a novel, selective A1 adenosine receptor agonist. 1623 Aug 91

Adenosine is a ubiquitous, endogenous purine involved in a variety of physiological and pathophysiological regulatory mechanisms. Adenosine has been proposed as an endogenous antiarrhythmic substance to prevent hypoxia/ischemia-induced arrhythmias. Adenosine (and its precursor, ATP) has been used in the therapy of various cardiac arrhythmias over the past six decades. Its primary indication is treatment of paroxysmal supraventricular tachycardia, but it can be effective in other forms of supraventricular and ventricular arrhythmias, like sinus node reentry based tachycardia, triggered atrial tachycardia, atrioventricular nodal reentry tachycardia, or ventricular tachycardia based on a cAMP-mediated triggered activity. The main advantage is the rapid onset and the short half life (1- 10 sec). Adenosine exerts its antiarrhythmic actions by activation of A1 adenosine receptors located in the sinoatrial and atrioventricular nodes, as well as in activated ventricular myocardium. However, adenosine can also elicit A2A, A2B and A3 adenosine receptor-mediated global side reactions (flushing, dyspnea, chest discomfort), but it may display also proarrhythmic actions mediated by primarily A1 adenosine receptors (e.g. bradyarrhythmia or atrial fibrillation). To avoid the non-specific global adverse reactions, A1 adenosine receptor- selective full agonists (tecadenoson, selodenoson, trabodenoson) have been developed, which agents are currently under clinical trial. During long-term administration with orthosteric agonists, adenosine receptors can be internalized and desensitized. To avoid desensitization, proarrhythmic actions, or global adverse reactions, partial A1 adenosine receptor agonists, like CVT-2759, were developed. In addition, the pharmacologically "silent" site- and event specific adenosinergic drugs, such as adenosine regulating agents and allosteric modulators, might provide attractive opportunity to increase the effectiveness of beneficial actions of adenosine and avoid the adverse reactions.
...
PMID:The Janus face of adenosine: antiarrhythmic and proarrhythmic actions. 2535 87