Vasodilator Therapy: Nitrates and Nicorandil

Area of Science:

• Pharmacology
• Cardiology
• Vascular Biology

Background:

• Nitrates have been a cornerstone in treating chronic stable angina for over 135 years.
• Their mechanism involves nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) pathways, leading to vasodilation, though cellular details remain under investigation.
• Current understanding highlights peripheral venous dilation, reduced cardiac preload, and coronary artery dilation as key anti-anginal effects.

Purpose of the Study:

• To provide an updated review on the pharmacological management of chronic stable angina.
• To discuss the roles of nitrates and nicorandil in angina prophylaxis and acute symptom relief.
• To highlight considerations for effective and safe clinical use, including side effects and tolerance.

Main Methods:

• Review of existing literature on nitrates and nicorandil in angina management.
• Analysis of physiological effects, including vasodilation and cellular signaling pathways.
• Discussion of clinical applications, side effects, and the phenomenon of nitrate tolerance.

Main Results:

• Short-acting nitrates provide rapid relief from angina attacks by counteracting ischemic mechanisms.
• Long-acting nitrates are recommended for angina prophylaxis, often as second-line therapy.
• Nicorandil acts as a vasodilator via NO donation and K-ATP channel opening, potentially offering cardioprotective effects.

Conclusions:

• Nitrates and nicorandil are effective in preventing angina symptoms.
• Clinical use requires careful consideration of side effects (headache, hypotension) and management of nitrate tolerance to prevent reduced efficacy and potential long-term cardiovascular risks.
• Optimizing dosing regimens is essential for sustained therapeutic benefit and patient safety.