Final answer:
An ACE Inhibitor decreases SVR and blood pressure, promotes the excretion of water and sodium by the kidneys, and does not retain potassium.
Step-by-step explanation:
An ACE Inhibitor (Angiotensin Converting Enzyme Inhibitor) has several effects on the body after a myocardial infarction. It decreases SVR (systemic vascular resistance) and blood pressure, which helps to reduce the workload on the heart. It also promotes the excretion of water and sodium by the kidneys, helping to decrease fluid volume in the body. However, an ACE Inhibitor does not retain potassium; instead, it may cause a slight increase in potassium excretion.