Acute Myocardial infarction

Case Presentation

Pharmacological rationale for the use of beta blockers and nitrates in the treatment of patients with ischaemic heart disease

The goals of treatment in acute myocardial infection are the restoration of blood flow to the coronary arteries and salvaging as much as possible of a functional myocardium . Nitrates and betablockers are some of the main medications used in the management of acute myocardial infarction Nitrates are beneficial due to their vasodilator effect . Nitrates are metabolized to nitric oxide in the endothelium of blood vessels (Rubenstein et al , 2006 , pp261 . The

nitric oxide has the effect of relaxing vascular smooth muscle causing the blood vessel lumen to dilate . Vasodilation leads to a reduction in cardiac afterload and preload . This decreased the oxygen requirements of the myocardium Vasodilation in the coronary arteries leads to an improvement in the flow of blood through the partially obstructed coronary vessels and also through the collateral vessels . Nitrates reverse the vasoconstriction that occurs during coronary occlusion (ACC /AHA , 2006 . When administered intravenously or sublingually , nitroglycerin has a rapid onset of action . Evidence for the use of nitroglycerin has shown substantive benefit in the long term following therapy for MI . It is useful in such cases when there is no residual ischemia or a severe pump dysfunction (McInnes , 2008 , pp255 . The use of nitroglycerin is however limited by side effects such as headache , low blood pressure and tachyplaxis (Reid et al , 2006 , pp62-63 . The tolerance to nitrates can be overcome by providing a nitrate-free interval...