ln stable angina-
**Core Concept**
The management of stable angina involves optimizing medical therapy to reduce the frequency and severity of angina episodes. The primary goal is to achieve optimal medical therapy to delay or prevent the need for revascularization.
**Why the Correct Answer is Right**
In stable angina, the use of beta-blockers is recommended as first-line therapy to reduce myocardial oxygen demand by decreasing heart rate and contractility. This is achieved through the blockade of beta-1 receptors in the heart, which reduces the effect of catecholamines on the heart rate and contractility. Additionally, beta-blockers also reduce the frequency and severity of angina episodes by decreasing myocardial oxygen demand.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because calcium channel blockers are not always recommended as first-line therapy in stable angina. While they can be used as an alternative to beta-blockers in certain patients, they are not the preferred initial treatment.
* **Option B:** This option is incorrect because nitrates are primarily used for acute management of angina episodes and are not recommended as long-term therapy for stable angina. They work by dilating coronary arteries and reducing myocardial oxygen demand, but their effects are short-lived and require frequent dosing.
* **Option D:** This option is incorrect because ACE inhibitors are not first-line therapy for stable angina. While they can be used in patients with coexisting hypertension or heart failure, they do not directly reduce myocardial oxygen demand and are not as effective as beta-blockers in preventing angina episodes.
**Clinical Pearl / High-Yield Fact**
Beta-blockers should be titrated to achieve a heart rate of 50-60 beats per minute in patients with stable angina to maximize their benefit and reduce the risk of adverse effects.
**Correct Answer: A. Beta-blockers are the first-line therapy for stable angina.**