**Question:** Current therapeutic status of milrinone in CHF is:

A. Supposed to be a vasodilator
B. Used as a first-line therapy
C. Considered as a rescue therapy
D. Discovered in 1979

**Core Concept:**
Milrinone is a phosphodiesterase-3 inhibitor, which belongs to the class of drugs known as inotropes. Inotropes are medications that increase contractility of the heart muscle, thereby improving cardiac output in patients with heart failure (CHF). Milrinone works by increasing cyclic adenosine monophosphate (cAMP) levels within the cardiomyocytes, leading to improved cardiac contractility and relaxation.

**Why the Correct Answer is Right:**
The correct answer is "Considered as a rescue therapy" (Option C) because milrinone is typically used when other medications and interventions have failed to provide adequate cardiac output and tissue perfusion in patients with severe CHF. As a vasodilator (Option A), it helps to improve cardiac output by increasing myocardial contractility, but it is not a primary therapy for CHF. Milrinone is not a first-line therapy (Option B) because it has several limitations, such as potential side effects, limited duration of action, and the need for close monitoring of hemodynamic parameters.

**Why Each Wrong Option is Incorrect:**

A. As explained above, milrinone is a rescue therapy, not a vasodilator (Option A).

B. Milrinone is not a first-line therapy due to its limitations like side effects, limited duration of action, and hemodynamic monitoring requirements (Option B).

D. Milrinone was discovered in 1979 (Option D), not its therapeutic status in CHF.

**Clinical Pearl:**
In patients with refractory CHF, milrinone can be considered as a rescue therapy when other options have failed. Its use should be closely monitored for potential side effects and hemodynamic changes to ensure optimal therapeutic outcomes and minimize harm.