Supraventricular arrhythmias and

Approved indications for propafenone include treatment of supraventricular arrhythmias and life-threatening ventricular arrhythmias in the absence of structural heart disease. Propafenone has been shown to increase mortality in patients with structural heart disease, and so extreme caution must be used in this subset of patients. As with flecainide, the patient should be hospitalized for initiation of therapy. 

The vagus nerve may be stimulated reflexly by various physical manoeuvres. Vagal stimulation may slow or terminate supraventricular arrhythmias and should if possible be carried out imder ECG control. 

Calcium channel blockers are used in the management of angina pectoris, hypertension, supraventricular arrhythmias, and subarachnoid hemorrhage. 

Timolol is an effective antihypertensive agent. It improves exercise tolerance in patients with angina pectoris. It substantially reduces the long-term risk of sudden death and reinfarction in patients surviving acute myocardial infarction. It has been shown to reduce the size of an acute myocardial infarction when given intravenously within 4 hours after the onset of symptoms. Timolol is effective in the treatment of supraventricular arrhythmias and in certain cases of recurrent ventricular tachycardia. 

It is frequently employed in the control and management of ventricular and supraventricular arrhythmias, and also in the treatment of angina pectoris. 

Other agents are also used for the treatment of manic-depressive disorders based on preliminary clinical results (177). The antiepileptic carbamazepine [298-46-4] has been reported in some clinical studies to be therapeutically beneficial in mild-to-moderate manic depression. Carbamazepine treatment is used especially in bipolar patients intolerant to lithium or nonresponders. A majority of Hthium-resistant, rapidly cycling manic-depressive patients were reported in one study to improve on carbamazepine (178). Carbamazepine blocks noradrenaline reuptake and inhibits noradrenaline exocytosis. The main adverse events are those found commonly with antiepileptics, ie, vigilance problems, nystagmus, ataxia, and anemia, in addition to nausea, diarrhea, or constipation. Carbamazepine can be used in combination with lithium. Several clinical studies report that the calcium channel blocker verapamil [52-53-9] registered for angina pectoris and supraventricular arrhythmias, may also be effective in the treatment of acute mania. Its use as a mood stabilizer may be unrelated to its calcium-blocking properties. Verapamil also decreases the activity of several neurotransmitters. Severe manic depression is often treated with antipsychotics or benzodiazepine anxiolytics. 

Disopyr mide. Disopyramide phosphate, a phenylacetamide analogue, is a racemic mixture. The dmg can be adininistered po or iv and is useful in the treatment of ventricular and supraventricular arrhythmias (1,2). After po administration, absorption is rapid and nearly complete (83%). Binding to plasma protein is concentration-dependent (35—95%), but at therapeutic concentrations of 2—4 lg/mL, about 50% is protein-bound. Peak plasma concentrations are achieved in 0.5—3 h. The dmg is metabolized in the fiver to a mono-AJ-dealkylated product that has antiarrhythmic activity. The elimination half-life of the dmg is 4—10 h. About 80% of the dose is excreted by the kidneys, 50% is unchanged and 50% as metabolites 15% is excreted into the bile (1,2). 

Phenytoin. Phenytoin sodium is sodium diphenylhydantoin [630-93-3] which is stmcturally related to the barbiturates. It was originally introduced as an anticonvulsant (18) (see Hypnotics, sedatives, and anticonvulsants) and later found to have antiarrhythmic properties (19), although not approved by the PDA for any arrhythmic indications. Phenytoin is effective in the treatment of ventricular arrhythmias associated with acute MI and with digitalis toxicity (20). It is not very effective in treatment of supraventricular arrhythmias (20). 

The answer is e. (Hardman, pp 858-874.) Because verapamil, a Ca channel blocker, has a selective depressing action on AV nodal tissue, it is an ideal drug for both immediate and prophylactic therapy of supraventricular tachycardia (SVT). Nifedipine, another Ca channel blocker, has little effect on SAT Lidocaine and adenosine are parenteral drugs with short ha If-lives and, thus, are not suitable for prophylactic therapy. Procainamide is more suitable for ventricular arrhythmias and has the potential for serious adverse reactions with long-term use. 

Esmolol hydrochloride is a competitive p-adrenergic receptor antagonist it is selective for pT adrenoceptors. In contrast to pindolol, esmolol has little intrinsic sympathomimetic activity, and it differs from propranolol in that it lacks membrane stabilizing activity Of all of the p-adrenergic blocking drugs, this compound has the shortest duration of action because it is an ester, it is hydrolyzed rapidly by plasma esterases and must be used by the intravenous route Esmolol is approved only for the treatment of supraventricular arrhythmias... 

Dihydropyridine channel blockers (e.g., nifedipine) have little benefit on clinical outcomes beyond symptom relief. The role of verapamil and diltiazem appears to be limited to symptom relief or control of heart rate in patients with supraventricular arrhythmias in whom /l-blockers are contraindicated or ineffective. 

Common supraventricular tachycardias requiring drug treatment are atrial fibrillation (AF) or atrial flutter, paroxysmal supraventricular tachycardia (PSVT), and automatic atrial tachycardias. Other common supraventricular arrhythmias that usually do not require drug therapy are not discussed in this chapter (e.g., premature atrial complexes, wandering atrial pacemaker, sinus arrhythmia, sinus tachycardia). 

Type Ic drugs profoundly slow conduction velocity while leaving refractoriness relatively unaltered. Although effective for both ventricular and supraventricular arrhythmias, their use for ventricular arrhythmias has been limited by the risk of proarrhythmia. 

Ideal candidates for /1-blockers include patients in whom physical activity is a prominent cause of attacks those with coexisting hypertension, supraventricular arrhythmias, or postmyocardial infarction angina and those with anxiety associated with anginal episodes. /1-Blockers may be used safely in angina and heart failure. 

Supramolecular structuring, 12 5-6 Supramolecular synthons, synthesis and structures of, 24 39-40 Supramolecules, formation of, 24 34 Supraventricular arrhythmias, 5 88, 104 Supraventricular tachycardia, 5 88, 101, 105, 108 Suprilent... 

Anxiety Disorder Due to a General Medical Condition with Panic Attacks. Many medical illnesses are associated with anxiety and even recurrent panic attacks. These include endocrine disorders, such as hyperthyroidism, hyperparathyroidism, hypoglycemia, and pheochromocytomas, inner ear (vestibular) dysfunction, seizure disorders, and cardiac (heart) disorders such as supraventricular tachycardia, mitral valve prolapse, and various arrhythmias, and carcinoid. A general physical examination, routine laboratory studies including electrolytes and... 

Digitoxin is used for chronic cardiac insufficiency, tachyarrhythmia form of atrial fibrillation, paroxysmal ciliary arrhythmia, and paroxysmal supraventricular tachycaria. Synonyms of this drag are cardigin, cordalin, crystodigin, purodigin, and others. 

Strophanthin is used in severe cardiovascular insufficiency, in particular after myocardial infarction, for chronic cardiac insufficiency, cardiac decompensation, supraventricular tachycardia, and ventricular arrhythmia. Synonyms of this drug are combetin, strofopan, and others. 

Verapamil is used for preventing angina pectoris attacks, arterial hypertension, and treating and preventing supraventricular arrhythmia (paroxysmal supraventricular tachycardia, atrial fibrillation, atrial flutter, extrasystole). Synonyms of this drug are isoptin, calan, fmoptin, falicard, manidone, and many others. 

Verapamil possesses antiarrhythmic, antianginal, and hypotensive activity. It reduces the myocardial need for oxygen by reducing contractility of the myocardium and slowing the frequency of cardiac contractions. It causes dilation of coronary arteries and increased coronary blood flow. It reduces tonicity of smooth musculature, peripheral arteries, and overall peripheral vascular resistance. It provides antiarrhythmic action in supraventricular arrhythmia. 

Verapamil is used to prevent attacks of stenocardia, arterial hypertension, and to treat and prevent supraventricular arrhythmia. 

Once the arrhythmia is controlled, it may be possible to reduce the dose, as necessary, to minimize side effects or effects on conduction. PSVT and PAF The recommended starting dose is 50 mg every 12 hours. Doses may be increased in increments of 50 mg twice daily every 4 days until efficacy is achieved. For PAF patients, a substantial increase in efficacy without a substantial increase in discontinuation for adverse experiences may be achieved by increasing the flecainide dose from 50 to 100 mg twice/day. The maximum recommended dose for patients with paroxysmal supraventricular arrhythmias is 300 mg/day. 

Cardiovascular events Hypertension, supraventricular arrhythmias, chest pain, and Ml have been observed in patients treated with peginterferon alfa-2a. 

Procainamide (Pwnestyl, Procan SR) is a derivative of the local anesthetic agent procaine. Procainamide has a longer half-life, does not cause CNS toxicity at therapeutic plasma concentrations, and is effective orally. Procainamide is a particularly useful antiarrhythmic drug, effective in the treatment of supraventricular, ventricular, and digitalis-induced arrhythmias. 

Phenytoin, like lidocaine, is more effective in the treatment of ventricular than supraventricular arrhythmias. It is particularly effective in treating ventricular arrhythmias associated with digitalis toxicity, acute myocardial infarction, open-heart surgery, anesthesia, cardiac catheterization, cardioversion, and angiographic studies. 

Sotalol possesses a broad spectrum of antiarrhythmic effects in ventricular and supraventricular arrhythmias. It has value in the management of patients with paroxys-... 

Arrhythmias, including prevention of recurrent paroxysmal supraventricular tachycardia and control of ventricular resting rate in chronic atrial fibrillation or flutter (with di-goxin) PO 240-480 mg/day in 3-4 divided doses. 

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