Angina is a type of chest pain caused by lack of blood flow to the heart. Most people with angina have coronary artery disease which is caused by a buildup of cholesterol and inflammation in the main arteries that supply the heart. Eventually the buildup can result in blockages that can lead to a heart attack.
Some people, especially women, can have angina without any significant blockages in the main arteries that supply the heart. This is called microvascular angina or small vessel angina. Microvascular angina is often underdiagnosed because confirming the diagnosis is much more complicated than for routine coronary artery disease. We do know that most patients with microvascular disease have some of the same traditional risk factors for coronary artery disease, like diabetes, high blood pressure, high cholesterol and/or tobacco use.
What Causes Microvascular Angina?
The cause of microvascular angina is not fully understood, but it is thought that the very tiny blood vessels supplying the heart (microcirculation) have decreased ability to regulate blood flow resulting in symptoms of angina. It is also thought that there is increased sensitivity of these small blood vessels to stimuli that constricts them.
Microvascular Angina Symptoms
Most patients with microvascular angina have recurrent chest pain that typically lasts longer than typical angina (often more than 20 minutes) and is often triggered by physical or emotional stress.
Microvascular angina can also produce:
- Shortness of breath
- Fatigue
- Sleep problems
- Pain or discomfort in jaw, neck, back, abdomen or arm
Microvascular Angina Risk Factors
Here are some risk factors for microvascular angina:
- Unhealthy diet
- Sedentary lifestyle
- Tobacco use
- High blood pressure
- Obesity
- Diabetes
- Estrogen deficiency
- Polycystic ovarian syndrome
- Autoimmune conditions (lupus, rheumatoid arthritis)
Diagnosing Microvascular Angina
Most patient will have an ECG, stress test and cardiac catheterization to help diagnosis microvascular angina. Patients with an abnormal stress test but no significant blockages seen in the coronary arties on catheterization are more likely to have microvascular angina. Sometimes, additional tests are done during the cardiac catheterization to help confirm the diagnosis.
Treating Microvascular Angina
Patients with microvascular angina have a worse prognosis than the general population, therefore diagnosis and appropriate treatment is important. Relieving pain, controlling symptoms and minimizing risk factors are often achieved through a combination of medications, healthy diet and an exercise program.
Some medications that can be used include:
- Aspirin
- ACE inhibitors, beta blockers and calcium channel blockers (blood pressure)
- Statins (lower cholesterol)
- Long-acting nitrates (reduce chest pain by widening blood vessels)
- Nitroglycerin (relaxes blood vessels)
Learn More about Angina