**Core Concept**
Ivabradine is a selective inhibitor of the I(f) channel in the sinoatrial node, which is responsible for the generation of the heart rate in the sinoatrial node. This action leads to a reduction in heart rate without affecting contractility or blood pressure.

**Why the Correct Answer is Right**
Ivabradine is specifically indicated for the treatment of heart failure in patients with a left ventricular ejection fraction (LVEF) of 35% or less, who are in sinus rhythm with a resting heart rate of 70 beats per minute or greater. By inhibiting the I(f) channel, ivabradine reduces the heart rate, which can improve cardiac function and reduce symptoms in patients with heart failure. This mechanism of action is unique among anti-arrhythmic drugs, which typically target other ion channels or receptors.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because ivabradine is not indicated for atrial fibrillation or flutter, which are types of supraventricular tachycardia.
**Option B:** This option is incorrect because ivabradine is not a beta-blocker, which is a different class of medication used to treat heart failure and hypertension.
**Option C:** This option is incorrect because ivabradine is not indicated for the treatment of hypertension, which is typically managed with other classes of medications such as ACE inhibitors or calcium channel blockers.

**Clinical Pearl / High-Yield Fact**
Ivabradine is often used in combination with beta-blockers to achieve a heart rate of 60 beats per minute or less in patients with heart failure, which is associated with improved outcomes.

**Correct Answer:** C.