dudefop
Forum Newbie
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A 58-year-old college professor had onset of a myocardial infarction(MI) 4 hours ago and is now in the intensive care unit(ICU). His electrocardiogram(ECG) shows an increasing incidence of short runs of ventricular tachycardia. Which of the following is the most appropriate antiarrhythmic drug to administer at this early time after his infarct?
(A) Amiodarone
(B) Flecainide
(C) Lidocaine
(D) Quinidine
(E) Verapamil
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Passed step1, Step2 CS. Now preparing for CK. Grad of Inha Univ. College of Medicine, South Korea.
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| deja_vu
Forum Senior
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Lignocaine
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| dr.wad
Forum Senior
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(C) lidocaine
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| tamerbashir
Forum Elite
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AMIODARONE
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| dudefop
Forum Newbie
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The answer is (C)
Patients with intermittent ventricular tachycarida following a myocardial infarction(MI) have an increased risk of death compared to a group of patients without this tachyarrhythmia. Lidocaine, a class Ib antiarrhythmic agent, is the least cardiodepressant of the drugs listed. Given intravenously, lidocaine has a rapid onset of action and reduces the incidence of ventricular fibrillation. However, high doses of lidocaine can depress myocardial contractility and may cause central nervous system(CNS) excitation, including hyperreflexia and seizures. Procainamide(not listed) can also be used intravenously for acute management of ventricular tachycardia after an MI.
Amiodarone(Choice A) and quinidine(choice D) prolong the duration of cardiac action potential, an action associated with an increased incidence of torsades de pointes. Note that flecainide(Choice B) [and possibly other class Ic drugs] may increase mortality when used prophylactically after a myocardial infarct. Verapamil(Choice E) is primariy used to treat supraventricular tachycardias.
___________________
Passed step1, Step2 CS. Now preparing for CK. Grad of Inha Univ. College of Medicine, South Korea.
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