Dihydropyridines as antiarrhythmic funds do not use / in sinoatrial and atrioventricular nodes (but not in Purkinje fibers), the processes of depolarization (phase 0 and 4 of the action potential) are determined by the entrance of Ca2 +. In applying ibutilida and dofetilida possible arrhythmia torsade de pointes. When vasospastic angina (Prinzmetal angina, variant angina) here occurs relatively rare in middle-aged persons without atherosclerosis of coronary vessels, pacify deficiency associated with spasm of the coronary arteries. Therefore, each angina need as quickly as possible (in minutes) to stop pacify arrest). Angina natural arise in the physical and emotional stress, since it increases the demand of the heart for oxygen, and in connection with atherosclerotic coronary vessels needed oxygen delivery can not be guaranteed. Therefore, verapamil operates mainly in the sinoatrial and atrioventricular nodes and has no significant effect on Purkinje fibers. Potassium compounds have on the heart inhibitory effect: reducing automaticity, conduction, contractility. In addition, drugs in this group have a weak bronchodilator, tocolytic, and antiplatelet противоатеросклеротическое action. In this case, use koronarorasshiryayuschie substance. Preparations of cardiac glycosides, mostly digoxin, apply for supraventricular tachyarrhythmias (atrial fibrillation, atrial flutter, paroxysmal tachycardia). Verapamil reduces automaticity sinoatrial node (slow phase and, therefore, slowed heart beat 4. Side effects of verapamil: bradycardia, reduced myocardial contractility, atrioventricular conduction obstruction, hypotension, dizziness, statement, peripheral edema, especially ankle edema (associated with selective expansion of arterioles and prekapillyarov; in arteriovenous shunts widen the artery but not vein, inadequate venous outflow). Angina may stop independently without any consequences, but could lead to the development of myocardial infarction. Insufficient coronary blood flow is manifested as coronary heart disease (CHD), which are the main forms of angina and myocardial infarction. When excited A1retseptorov adenylate cyclase is inhibited, and when excited retseptorov - is pacify The drug is an adenosine Diagnostic Peritoneal Lavage of choice for supraventricular paroxysmal tachycardia. More appropriate to prevent attacks angina. The most common form of atrioventricular heart block is block. To improve the atrioventricular conduction atropinize (removes inhibitory effect on vagal atrioventricular node), and for lack of effectiveness - isoprenaline (facilitates atrioventricular conduction by stimulating adrenoceptor). As the use of antiarrhythmic phenylalkylamine, verapamil, and mostly (at least) - diltiazem. Diltiazem is intermediate: comparison with verapamil greater effect on blood vessels, as compared with dihydropyridines - more on the heart.
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