What is coronary microvascular dysfunction and why does it affect women more often?

“Coronary microvascular dysfunction is an abnormality affecting the small blood vessels of the heart, namely the arterioles and capillaries that regulate blood flow to the myocardium,” explains Dr. Castelvecchio.

Under normal conditions, these vessels dilate or constrict according to the body's needs. When this mechanism becomes impaired, the heart may receive less oxygen, particularly during physical exertion or stressful situations, causing symptoms similar to those of classic coronary artery disease.

Unlike obstructive coronary artery disease, coronary microvascular dysfunction does not affect the large coronary arteries and is often not detectable with conventional diagnostic tests.

The causes of coronary microvascular dysfunction are often multifactorial and may coexist.

At the root of the condition is frequently endothelial dysfunction, meaning an abnormality of the endothelium, the thin inner lining of blood vessels, which loses its ability to regulate vasodilation properly.

The main risk factors include:

• arterial hypertension;
• diabetes;
• high cholesterol levels;
• smoking;
• obesity;
• sedentary lifestyle;
• chronic inflammation.

“In addition, hormonal changes may play an important role, which is why this condition is particularly common in women, especially after menopause,” adds the cardiologist.

Coronary microvascular dysfunction is closely linked to gender-specific medicine.

“Women more frequently experience myocardial ischemia in the absence of significant coronary artery stenosis. This phenomenon is often related precisely to microvascular dysfunction,” emphasizes Dr. Castelvecchio.

After menopause, declining estrogen levels may negatively affect vascular function.

“Estrogens exert a protective effect on the endothelium and circulation. Their reduction can promote vascular stiffness and alterations in the microcirculation.”

For this reason, cardiac symptoms should never be dismissed, even when initial diagnostic tests appear normal.

Symptoms may resemble those of angina pectoris but are sometimes subtler or atypical. According to Dr. Castelvecchio, patients commonly report:

• chest pain or pressure;
• shortness of breath;
• fatigue;
• reduced exercise tolerance.

Symptoms in women

In women, symptoms may present in a less “classic” manner, including:

• nausea;
• pain in the back, jaw, or arms;
• profound fatigue;
• shortness of breath.

“This contributes to diagnostic delays and to the underestimation of the condition.”

Diagnosis can be challenging and often requires specialist evaluation.

“Sometimes an electrocardiogram or exercise stress test may suggest ischemia, while coronary angiography reveals no significant narrowing of the coronary arteries,” explains Dr. Castelvecchio.

To investigate further, specific diagnostic tests may be used, including:

• stress echocardiography;
• cardiac magnetic resonance imaging (MRI);
• cardiac PET imaging;
• coronary CT angiography;
• invasive coronary microvascular assessment.

“One of the most useful tools is the evaluation of coronary flow reserve, which allows us to determine whether the microcirculation responds appropriately to the heart’s demands.”

Although often underestimated, this condition is far from benign.

“It is not a harmless disorder. It can significantly affect quality of life and, in some cases, increase the long-term risk of cardiovascular events,” stresses the specialist.

Patients may develop:

• recurrent myocardial ischemia;
• repeated hospital admissions;
• limitations in daily activities;
• increased cardiovascular risk.

Treatment is based on a personalized approach.

“The first step is correcting cardiovascular risk factors and improving lifestyle habits,” says Dr. Castelvecchio.

Recommended measures include:

• a balanced diet;
• regular physical activity;
• weight management;
• smoking cessation;
• stress reduction.

Pharmacological treatment

Depending on the patient's symptoms and underlying mechanisms, medications may include:

• beta-blockers;
• calcium channel blockers;
• ACE inhibitors;
• statins;
• anti-anginal medications.

Treatment should always be tailored to the individual patient.

Prevention is possible through early management of cardiovascular risk factors.

“Paying attention to the body's signals and not ignoring symptoms such as shortness of breath or chest pain, even when initial tests are negative, is essential,” concludes Dr. Castelvecchio.

Appropriate cardiology follow-up, particularly for postmenopausal women or individuals with a family history of cardiovascular disease and other risk factors, can make a significant difference.

Recognizing coronary microvascular dysfunction means providing an explanation for symptoms that often remain unexplained and establishing a targeted diagnostic and therapeutic pathway. Early diagnosis can significantly improve quality of life and reduce the risk of future cardiovascular complications.