Antiarrhythmic Drugs

| Home | | Medicinal Chemistry |

Chapter: Medicinal Chemistry : Antiarrhythmic Drugs

Antiarrhythmic agents corrects the arrhythmia of the heart. Cardiac arrhythmias are frequent problems in clinical practice, occurring in up to 25% of the patients treated with digitalis, 50% of the anaesthetized patients, and over 8% of the patients with acute myocardial infarction.


Antiarrhythmic Drugs

INTRODUCTION

Antiarrhythmic agents corrects the arrhythmia of the heart. Cardiac arrhythmias are frequent problems in clinical practice, occurring in up to 25% of the patients treated with digitalis, 50% of the anaesthetized patients, and over 8% of the patients with acute myocardial infarction. Many factors can precipitate or exacerbate arrhythmias, ischaemia, hypoxia, acidosis, alkalosis, electrolyte abnormalities, excessive catecholamine exposure, autonomic influences, drug toxicity, over stretching of cardiac fibres, and the presence of any diseased tissue. However, all the arrhythmias results from the following:

  1. Disturbances in impulse formation

  2. Disturbances in impulse conduction

  3. Or both

The different types of cardiac arrhythmias are the following:

  1. Extra systole: Premature beats due to abnormal automaticity or after depolarization, arising from atrioventricular (AV) node, atrium, or ventricle.

  2. Paroxysmal supraventricular tachycardia: Sudden onset of atrial tachycardia mostly due to circus re-entry type within or around the AV node.

  3. Atrial flutter: Higher impulse and the arterial beat upto 200–350/min.

  4. Atrial fibrillation: Arterial fibres are activated asynchronously at the rate of 300–550/min.

  5. Ventricular tachycardia: It is a run of four consecutive ventricular extra systoles. It may be sustained or unsustained arrhythmia due to discharge from ectopic focus.

  6. Torsades de pointes: Twisting of valves leads to polymorphic ventricular charge and produces asynchronous complexes.

  7. Ventricular fibrillation: Fractional activation of ventricles resulting in incordinated concentration of fibres with loss of pumping function.

Atrio-ventricular block: It is due to depression of the impulse conduction through AV node and bundle of his due to vagal influence and ischaemias.


Contact Us, Privacy Policy, Terms and Compliant, DMCA Policy and Compliant

TH 2019 - 2022 pharmacy180.com; Developed by Therithal info.