USMLE (United States Medical Licensing Examination) Step 1 Practice Exam

Which of the following outcomes is expected when using Spironolactone in heart failure patients with a low ejection fraction?

1. Increased heart rate

2. Decreased survival rates

3. Improved ventricular remodeling

4. Increased fibrosis

The correct answer is: Improved ventricular remodeling

Spironolactone is an aldosterone antagonist that is commonly used in the management of heart failure, particularly in patients with reduced ejection fraction. One of the key benefits of spironolactone in this context is its ability to improve ventricular remodeling. Ventricular remodeling refers to the changes in size, shape, and function of the heart after injury, such as that caused by myocardial infarction or chronic pressure overload. In heart failure with low ejection fraction, neurohormonal activation, particularly from the renin-angiotensin-aldosterone system (RAAS), contributes to maladaptive remodeling processes that can worsen heart function over time. Spironolactone works by inhibiting the effects of aldosterone, which is involved in sodium retention, potassium excretion, and increased blood pressure. By blocking aldosterone, spironolactone helps to prevent the harmful effects of excess aldosterone, including fibrosis (scarring) of the myocardium, and promotes a more favorable remodeling process. Consequently, this leads to improvements in heart function and can result in better outcomes for patients with heart failure. Studies have demonstrated that the use of spironolactone in heart failure with reduced ejection fraction can lead to a decrease in