2025 Summary: ANOCA, INOCA, and MINOCA – Clinical Overview
2025 Summary: ANOCA, INOCA, and MINOCA – Clinical Overview
1-ANOCA (Angina with No Obstructive Coronary Arteries): Clinical term for chest pain without major coronary obstruction (<50%). May be ischemic or non-ischemic.
2-INOCA (Ischemia with No Obstructive Coronary Arteries): Confirmed myocardial ischemia (via stress testing or imaging), but no significant CAD on angiography. Common in women.
3- MINOCA(MI with Non-Obstructive Coronary Arteries): Fulfills MI criteria (troponin elevation, ECG changes) but coronary arteries show no >50% stenosis.
4- Evaluation Strategy:
– Rule out alternate diagnoses (e.g. PE, sepsis, myocarditis)
– Use OCT/IVUS for plaque disruption or SCAD
– Cardiac MRI to distinguish takotsubo/myocarditis
– Use CFR, IMR, and provocative tests if available.
5- Treatment:
– Tailored by mechanism
– Atherosclerotic: statins, ACEi, BB, antiplatelets
– Vasospasm: CCBs, nitrates
– Microvascular: BB, ACEi, statins
– Avoid unnecessary dual antiplatelet therapy.
6- Prognosis:
– Previously thought benign, now known to have 4–5% 1-year mortality
– Increased risk of recurrent angina, heart failure, especially in women.
7- Clinical Tip:
– INOCA and ANOCA are often underdiagnosed
– Mislabeling as ‘non-cardiac chest pain’ leads to under-treatment
8- Patient scenario:
A 52-year-old woman comes to your clinic complaining of chest pain. Her ECG is non-diagnostic, and cardiac enzymes are slightly elevated. Coronary angiography shows no significant blockage (<50%).
9- Quick Summary – INOCA, Microvascular Angina, and Variant Angina (Prinzmetal’s):
• INOCA stands for Ischemia with No Obstructive Coronary Arteries. It refers to chest pain or signs of myocardial ischemia without significant coronary artery blockages.
• Microvascular angina is a subtype of INOCA caused by dysfunction of the small coronary vessels (microcirculation). It’s often exercise-induced and not visible on traditional angiograms.
• Variant angina (also called Prinzmetal’s angina) is also a form of INOCA, but caused by spasm in the large epicardial coronary arteries, usually at rest and often with transient ST-elevation.
Key difference:
• Microvascular angina = small vessel dysfunction
• Variant angina = large vessel (epicardial) spasm
Now what?
Step-by-step Evaluation:
1. First, rule out other serious conditions:
• Could it be pulmonary embolism, sepsis, or myocarditis?
→ Do basic labs, imaging, and consider Cardiac MRI to check for myocarditis or Takotsubo cardiomyopathy.
2. If MI is suspected but arteries are clear:
• Think about plaque rupture or SCAD (spontaneous dissection).
→ Use OCT or IVUS during angiography to detect subtle findings missed by standard imaging.
3. If chest pain persists and ischemia is suspected:
• Assess for microvascular angina or vasospasm.
→ Perform CFR (coronary flow reserve), IMR, or acetylcholine testing if available.
Reference (2025):
– 2025 ESC Insights on INOCA/MINOCA: https://www.escardio.org/Congresses-&-Events/Congress-Resources/2025/inoca-minoca-clinical-management
– AHA Scientific Statement: https://www.ahajournals.org/doi/10.1161/CIR.0000000000000963
