Coronary artery disease without blockage (non-obstructive CAD) is a condition in which symptoms such as chest pain persist even though no significant blockage is seen on coronary angiography; it also includes clinical definitions such as INOCA and ANOCA. On this page, we look at information about this condition and EECP's possible role.
In the cardiology literature, the terms INOCA (Ischemia with No Obstructive Coronary Artery disease) and ANOCA (Angina with No Obstructive Coronary Arteries) are used to describe this picture. Both terms describe situations in which symptoms such as chest pain, pressure, or shortness of breath during exertion persist even though no significant narrowing is seen in the large arteries on coronary angiography.
This picture is often underpinned by coronary microvascular dysfunction (dysfunction of the heart's small vessels) or coronary vasospasm; together, these two mechanisms are often referred to as "microvascular angina." These related concepts are also discussed from different perspectives on our angina and broader coronary artery disease pages.
Standard coronary angiography is a method designed to visualize blockages in the heart's large arteries; it does not directly show the function of the small vessels (the microvascular circulation). Because of this, the source of persistent chest pain in a patient whose angiography comes back "clean" may not be immediately clear. The fact that symptoms can appear either with exertion or at rest, occur more often in women, and are not always easily confirmed with standard tests can prolong the diagnostic process.
For this reason, in patients suspected of having INOCA/ANOCA, the cardiology team generally proceeds with a more detailed evaluation.
Studies on EECP in the field of INOCA/ANOCA and microvascular angina are limited in number, and this topic continues to be researched. While current data suggest that EECP may help support the microcirculation and contribute to a reduction in symptoms in some patients, this is not a guarantee or a definitive cure. In this patient group, EECP is considered as a complementary option — not a replacement for current treatment — when deemed appropriate by the cardiology team. You can review the details of the relevant scientific studies on our Clinical Evidence page.
Symptoms of non-obstructive CAD can vary from person to person. EECP is not a method guaranteed to eliminate symptoms completely; it is recommended to be considered alongside lifestyle adjustments, medication, and regular cardiology follow-up.
Even without blockage in the large vessels, chest pain can persist due to causes such as microvascular dysfunction or coronary spasm; this requires a detailed evaluation.
No, no absolute guarantee can be given. EECP may be considered a supportive approach that can help reduce symptoms in some patients.
If needed, your cardiology team can assess microvascular function with additional tests; this process is directed by your doctor.
The process begins with a review of your existing angiography and test results, along with a detailed examination.
INOCA and ANOCA are clinical terms describing ischemia/angina without blockage, and they are considered part of the non-obstructive CAD spectrum. They are frequently associated with microvascular dysfunction or coronary vasospasm.
Diagnosis begins with a detailed symptom assessment and, if deemed necessary, may be supported by functional tests or advanced imaging methods. This process is guided entirely by your cardiology team.
Get a free preliminary assessment from our cardiology team for your ongoing symptoms.