## **Core Concept**
Prinzmetal's angina, also known as variant angina, is a type of angina pectoris caused by transient coronary artery spasm. The management of Prinzmetal's angina focuses on relieving the spasm and restoring blood flow to the heart muscle. This is typically achieved using vasodilators, particularly calcium channel blockers.

## **Why the Correct Answer is Right**
The correct answer, **D. Atenolol**, is a beta-blocker. Beta-blockers are generally contraindicated in Prinzmetal's angina because they can worsen vasospasm by leaving alpha-mediated coronary artery constriction unopposed. Beta-blockers block beta-2 receptors, which are involved in vasodilation, thereby potentially increasing the relative vasoconstrictive effect mediated by alpha-1 receptors.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Nifedipine is a calcium channel blocker that causes vasodilation and is used to treat Prinzmetal's angina.
- **Option B:** Verapamil is another calcium channel blocker effective in treating Prinzmetal's angina by reducing coronary artery spasm.
- **Option C:** Isosorbide dinitrate is a nitrate that provides immediate relief by releasing nitric oxide, a potent vasodilator, and is used in the management of Prinzmetal's angina.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that beta-blockers, while cornerstone in the treatment of typical angina and myocardial infarction, are generally avoided in Prinzmetal's angina due to their potential to worsen coronary spasm. Always consider the pathophysiology of the specific type of angina when choosing treatment.

## **Correct Answer:** D. Atenolol