Cardiac syndrome X

Cardiac Syndrome X (CSX) is a condition characterized by angina-like chest pain, a positive stress test indicative of myocardial ischemia, but with unobstructed coronary arteries on angiography. The term "Syndrome X" was first introduced in 1973 by Kemp to describe these patients with anginal symptoms but without the coronary artery blockages typically associated with angina pectoris. Despite normal coronary angiograms, patients with Cardiac Syndrome X experience genuine chest pain and have a decreased quality of life similar to those with obstructive coronary artery disease.

Etiology and Pathophysiology

The exact cause of Cardiac Syndrome X is not fully understood, but it is thought to involve microvascular dysfunction. This can include endothelial dysfunction, abnormal coronary microvascular reactivity, or reduced coronary flow reserve. These microvascular abnormalities can lead to impaired myocardial perfusion, even in the absence of macroscopic coronary artery blockages.

Clinical Presentation

Patients with Cardiac Syndrome X typically present with chest pain that is similar to that of angina pectoris. The pain is often described as constricting, burning, or tightness in the chest, and it may radiate to the arms, neck, or jaw. The chest pain is usually precipitated by physical exertion or emotional stress and is relieved by rest or nitroglycerin.

Diagnosis

The diagnosis of Cardiac Syndrome X is made by excluding obstructive coronary artery disease in patients who present with angina-like chest pain. This involves performing a coronary angiogram, which shows normal coronary arteries. Additional tests may include stress testing, which shows signs of myocardial ischemia, and non-invasive imaging studies to assess for microvascular dysfunction.

Treatment

Treatment of Cardiac Syndrome X focuses on symptom relief and improving quality of life. Options include anti-anginal medications such as beta-blockers, calcium channel blockers, and nitrates. Lifestyle modifications, including regular exercise and stress management, are also recommended. In some cases, antidepressants or other medications may be used to manage pain perception.

Prognosis

The prognosis of Cardiac Syndrome X is generally good in terms of survival, but the condition can significantly impair quality of life due to ongoing chest pain and limitations on physical activity. It is important for patients to have a comprehensive management plan and regular follow-up with their healthcare provider.

Epidemiology

Cardiac Syndrome X is more common in women than in men and typically affects middle-aged individuals. The prevalence of the condition is not well-defined, as it is often underdiagnosed due to the absence of coronary artery blockages on angiography.

See Also

• Microvascular angina
• Angina pectoris
• Coronary artery disease
• Endothelial dysfunction