What hemodynamic effect would you expect after nitroglycerin administration in ACS?

What hemodynamic effect would you expect after nitroglycerin administration in ACS?

• A. Increased afterload
• B. No change in vascular tone
• C. Decreased preload and possible decrease in afterload
• D. Decreased preload only

Answer: (C)

Nitroglycerin’s main action is venodilation, which lowers the amount of blood returning to the heart. In ACS this reduces preload, meaning the left ventricle fills with less volume and pressure (lower LV end-diastolic pressure and wall stress). At higher doses it also dilates arteries, which can lower afterload as systemic vascular resistance falls. Together, decreased preload and the potential decrease in afterload reduce myocardial wall tension and oxygen demand, helping relieve ischemia. So the expected hemodynamic change is decreased preload, with a possible decrease in afterload depending on the dose.

Nitroglycerin’s main action is venodilation, which lowers the amount of blood returning to the heart. In ACS this reduces preload, meaning the left ventricle fills with less volume and pressure (lower LV end-diastolic pressure and wall stress). At higher doses it also dilates arteries, which can lower afterload as systemic vascular resistance falls. Together, decreased preload and the potential decrease in afterload reduce myocardial wall tension and oxygen demand, helping relieve ischemia. So the expected hemodynamic change is decreased preload, with a possible decrease in afterload depending on the dose.