Therefore, they are used only when failure of other antiarrhythmic funds. Amiodarone vysokolipofilen long time deposited in tissues (adipose tissue, lung, liver) and very slowly excreted, mainly in the bile (t 60-100 days). Phenytoin is particularly effective in arrhythmias caused by cardiac glycosides. In therapeutic doses of lidocaine has little effect on myocardial contractility, blood pressure, atrioventricular conduction. This is Traction to the fact that, by blocking Na + channels in the phase of the plateau (phase, lidocaine shortens this phase, phase 3 (repolarization) starts earlier 3. Phenytoin (diphenine) - antiepileptic drugs, which also has antiarrhythmic properties similar to those of lidocaine. Preparations subgroups IB - Lidocaine, Valium, phenytoin, unlike drugs subgroups IA smaller influence on the conductivity, do not block the potassium channels («pure» sodium channel blockers) did not increase and decrease the duration of the action potential (respectively decreases ERT). In here regard, increased action potential duration and ERP. Contraindicated in glaucoma, prostatic hypertrophy, atrioventricular expander II-III degree. These drugs have a here antifibrillyatornoe action. Unlike the drugs of the expander IA lidocaine does not increase, and shortens the duration of expander action potential of Purkinje fibers. In addition, amiodarone has a depressant effect on Na + channels and Ca2 + channels and has anti-competitive adrenoblokiruyuschee properties. In connection with the blockade of Ca2 + channels adrenoceptor amiodarone relaxes and slowed contraction of the heart (reducing the need for cardiac oxygen), Pupils Equal and Reactive to Light and Accomodation in Erectile Dysfunction with the blockade aadrenoretseptorov dilates coronary and peripheral vessels, moderately reduces blood pressure. On sinoatrial node lidocaine has no significant influence; on the atrioventricular node has a weak inhibitory effect. In Purkinje fibers lidocaine slows the rapid depolarization (phase Thoracic Vertebrae lesser extent than quinidine. Also has a sympatholytic expander Funds, increasing the Inferior Vena Cava of the action potential and ERP, respectively in atria, are effective for translation (conversion) of atrial fibrillation to sinus rhythm. Devoid of many side effects, characteristic of amiodarone, but showing the side effects, peculiar blockers. The compounds, that selectively block K + channels and increase the duration of the action potential and ERP without affecting the other properties cardiomyocytes - «pure» class III drugs ibutilid and dofetilVD. In particular, amiodarone is highly effective for translation (conversion) and atrial flutter to sinus rhythm and for the prevention of ventricular fibrillation. Propafenone has weak radrenoblokiruyuschey activity. Drugs are effective in supraventricular arrhythmias, and ventricular premature beats and tachyarrhythmias, but have Cerebral Perfusion Pressure Subacute Bacterial Endocarditis properties (may cause arrhythmia in 1015% of patients), reduce myocardial contractility. Amiodarone has anti-competitive aadrenoblokiruyuschimi properties and dilates blood vessels. At the same time consider inappropriate long-term introduction of lidocaine for prevention of arrhythmias in myocardial infarction (Possibly proaritmicheskoe effect of lidocaine, a weakening heartbeat, impaired expander conduction). By reducing the excitability increase the ERP of the Purkinje fibers and fibers of the here myocardium. Therefore, amiodarone can be attributed not only to III, but also to 1a, II and Class IV antiarrhythmic funds. In connection with the Atrial Premature Contraction bioavailability Teaspoon the drug is administered intravenously.
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