Which of the following sho-acting selective betablocker drug is used in the management of arrythmia: March 2010

Ans. B: Esmolol Esmolol is a cardioselective beta-1 receptor blocker with rapid onset, a very sho duration of action, and no significant intrinsic sympathomimetic or membrane stabilising activity at therapeutic dosages. It is a class II antiarrhythmic. Esmolol decreases the force and rate of hea contractions by blocking beta-adrenergic receptors of the sympathetic nervous system, which are found in the hea and other organs of the body. Esmolol prevents the action of two naturally occurring substances: epinephrine and norepinephrine.