1. A patient with acute heart failure is prescribed a medication that increases cardiac contractility. Which pharmacological agent achieves this by inhibiting phosphodiesterase? A. Nitroglycerin B. Dobutamine C. Milrinone D. Enalapril Answer: C. Milrinone Rationale: Milrinone is a phosphodiesterase inhibitor that increases intracellular cyclic AMP, leading to increased calcium influx into myocardial cells, thereby increasing cardiac contractility. 2. In managing a patient with cardiogenic shock, which vasopressor is preferred to increase myocardial perfusion pressure? A. Dopamine B. Norepinephrine C. Epinephrine D. Phenylephrine Answer: B. Norepinephrine Rationale: Norepinephrine is the vasopressor of choice in cardiogenic shock because it increases systemic vascular resistance, leading to an increase in blood pressure and myocardial perfusion pressure without significantly increasing heart rate. 3. A nurse is caring for a patient who is receiving vasodilator therapy for heart failure. Which hemodynamic parameter is the primary target for improvement with this therapy? A. Cardiac output B. Systemic vascular resistance C. Pulmonary capillary wedge pressure D. Central venous pressure Answer: B. Systemic vascular resistance Rationale: Vasodilators are used in heart failure to reduce systemic vascular resistance, which decreases the workload on the heart and improves cardiac output. 4. When administering a beta-blocker to a patient with hypertension and