**Core Concept**
Verapamil is a calcium channel blocker that inhibits the influx of calcium ions into cardiac and smooth muscle cells. This action results in vasodilation and reduced cardiac contractility, making it useful in various cardiovascular conditions.

**Why the Correct Answer is Right**
Verapamil is used to treat hypertension, angina pectoris, and supraventricular tachycardias (SVTs) due to its ability to reduce cardiac contractility and slow conduction through the AV node. The drug is also effective in preventing migraine headaches, as it relaxes blood vessels and reduces vasospasm.

**Why Each Wrong Option is Incorrect**
**Option A:** Verapamil is not typically used to treat heart failure, as it can worsen cardiac function by reducing contractility.
**Option B:** Verapamil can actually be beneficial in the management of atrial fibrillation, as it can slow conduction through the AV node and reduce ventricular rate.
**Option C:** Verapamil is not used to treat ventricular tachycardias, as it can worsen cardiac function and increase the risk of torsades de pointes.
**Option D:** Verapamil is not used to treat Wolff-Parkinson-White (WPW) syndrome, as it can worsen the condition by increasing conduction through the accessory pathway.

**Clinical Pearl / High-Yield Fact**
Verapamil is a non-dihydropyridine calcium channel blocker, which means it primarily affects the L-type calcium channels in the heart and smooth muscle. This makes it a useful treatment for conditions such as SVTs and hypertrophic cardiomyopathy.

**Correct Answer: C. Verapamil is not typically used to treat ventricular tachycardias, as it can worsen cardiac function and increase the risk of torsades de pointes.**