Antiarrhythmia

• Class III antiarrhythmics are used to treat ventricular arrhythmias, including torsades de pointes.
• 1 A Prolong action potential, disopairamide, quinidine, prokainamide. Moderate NA
• 1 b shorten action potential mexilitine, tocainamide, ​lidocaine, phenytoin. Weak NA
• 1 C noeffect ​potential morcizine, fleca​inide, propfenone. Strong NA
• Class 3 K channel blocker. Amiodarone has 32% iodine used in management of arterial fibrilization & Vtach. Toxic effect iodine containing leads to pulmonary fibrosis, wolf tchaikof test and hepatoxic. Increase iodine less than 10 to 14 days leads to hypothyroidism. Increase iodine more than 14 days leads to hyperthyroidism
• Class 3 K channel blocker dronedarone ​ devode of iod​ine content
• Sotalol is the only class three ​locker
• Verapamil is the most cardio selective class 4 calcium channel blockers it is the first line in chronic proximal supra Vtach
• Adenosine is the first line in acute proximal supraventricular tachycardia. Toxic effect is bronchospasm, remedy pre treatment with saba
• anti arithmetic drug ​magnesium sulfate is the ​First line for torsades-de-pointes
• Anti arithmetic drug digoxin is used in the management of arterial-fibrosis