Microvascular angina

Microvascular Angina

Illustration of a clogged heart artery, which can be related to microvascular angina.

Microvascular angina, also known as cardiac syndrome X, is a condition characterized by chest pain (angina) that occurs due to abnormalities in the small blood vessels of the heart. Unlike typical angina, which is caused by blockages in the larger coronary arteries, microvascular angina involves the smaller coronary microvasculature.

Pathophysiology

Microvascular angina is thought to result from dysfunction of the endothelium and smooth muscle cells in the small coronary arteries. This dysfunction leads to impaired vasodilation and increased vascular resistance, which reduces blood flow to the heart muscle and causes ischemic pain. The exact mechanisms are not fully understood, but it is believed that inflammation, oxidative stress, and endothelial dysfunction play significant roles.

Symptoms

Patients with microvascular angina typically experience chest pain that is similar to that of stable angina, but it may occur more frequently and last longer. The pain is often described as a pressure or tightness in the chest and may be accompanied by shortness of breath, fatigue, and dizziness. Unlike typical angina, the pain may not be relieved by nitroglycerin or rest.

Diagnosis

Diagnosing microvascular angina can be challenging because standard tests for coronary artery disease, such as coronary angiography, often show normal results. Diagnosis is typically made based on the patient's symptoms, exclusion of other causes of chest pain, and specialized tests such as coronary flow reserve measurement or magnetic resonance imaging (MRI) to assess microvascular function.

Treatment

Treatment for microvascular angina focuses on relieving symptoms and improving quality of life. Common treatments include:

• Beta-blockers and calcium channel blockers to reduce heart workload and improve blood flow.
• ACE inhibitors or angiotensin II receptor blockers to improve endothelial function.
• Statins to reduce inflammation and improve endothelial health.
• Lifestyle modifications such as regular exercise, a heart-healthy diet, and stress management.

Prognosis

The prognosis for patients with microvascular angina varies. While the condition can be chronic and impact quality of life, it is generally not associated with the same risk of myocardial infarction or death as obstructive coronary artery disease. However, ongoing management and monitoring are important to prevent complications.

Related Pages

• Coronary artery disease
• Angina pectoris
• Endothelial dysfunction
• Ischemic heart disease