Rentrop classification of coronary collaterals

Rentrop classification of coronary collaterals

What is the Rentrop classification of coronary collaterals?


The Rentrop classification is an angiographic grading system used to describe the extent of coronary collateral circulation (natural bypass vessels that form to supply myocardium distal to an occlusion).

It is based on the degree of collateral vessel filling visualized during coronary angiography:

Rentrop Classification of Coronary Collaterals

  • Grade 0No visible collateral vessels.
  • Grade 1Collateral filling of side branches of the occluded artery without visualization of the epicardial segment.
  • Grade 2Partial filling of the epicardial segment of the occluded artery by collateral vessels.
  • Grade 3Complete filling of the epicardial segment of the occluded artery by collateral vessels.

📌 Clinical importance:

  • Higher Rentrop grades (2–3) indicate well-developed collateral circulation, often associated with better myocardial viability and protection against ischemia during coronary occlusion.
  • However, even with Rentrop grade 3 collaterals, flow reserve may be limited compared to a normal coronary artery.

Would you like me to also create a diagram/infographic of the Rentrop classification (Grade 0–3) for quick visual learning?

Rentrop Classification of Coronary Collateral Circulation
Grade Short Label Angiographic Description
0 No collaterals No visible collateral channels.
1 Side-branch filling only Collateral filling of side branches of the occluded artery, without visualization of the epicardial segment.
2 Partial epicardial filling Collateral vessels produce partial filling of the epicardial segment of the occluded artery.
3 Complete epicardial filling Collateral vessels produce complete filling of the epicardial segment of the occluded artery.

Tip: On small screens, swipe horizontally to view the full table.

1. What does Rentrop Grade 0 indicate?
Show Explanation
Rentrop Grade 0 = no visible collateral circulation.
2. Which grade describes collateral filling of side branches only, without epicardial filling?
Show Explanation
Grade 1 = filling of side branches only, not the epicardial vessel.
3. Which grade indicates partial filling of the epicardial artery?
Show Explanation
Grade 2 = partial filling of epicardial segment by collaterals.
4. Rentrop Grade 3 refers to?
Show Explanation
Grade 3 = complete filling of epicardial artery via collaterals.
5. Which Rentrop grade provides the best myocardial protection?
Show Explanation
Grade 3 collaterals provide maximal protection against ischemia.
6. In Rentrop classification, which grade represents no collateral channels seen on angiography?
Show Explanation
Grade 0 = complete absence of collateral vessels.
7. Which Rentrop grade is defined by collateral filling of side branches without main artery visualization?
Show Explanation
Grade 1 = collaterals visible in side branches only.
8. Partial but not complete filling of epicardial artery corresponds to?
Show Explanation
Grade 2 = partial filling of epicardial artery segment.
9. Which grade represents full collateral perfusion of the epicardial artery?
Show Explanation
Grade 3 = complete filling of epicardial artery segment.
10. Rentrop Grade 2 collaterals supply how much of the epicardial segment?
Show Explanation
Grade 2 collaterals = partial epicardial filling.
11. Rentrop Grade 1 indicates:
Show Explanation
Rentrop Grade 1: Collaterals fill side branches of the occluded artery, without epicardial filling.
12. Rentrop Grade 2 indicates:
Show Explanation
Rentrop Grade 2: Collaterals produce partial filling of the epicardial segment of the occluded artery.
13. Rentrop Grade 3 signifies:
Show Explanation
Rentrop Grade 3: Collaterals produce complete filling of the epicardial segment of the occluded artery.
14. Which Rentrop grade represents absence of collateral circulation?
Show Explanation
Rentrop Grade 0: No visible collateral vessels are present.
15. Partial filling of the epicardial segment is seen in:
Show Explanation
Partial epicardial filling corresponds to Rentrop Grade 2.
16. Complete filling of the epicardial segment by collaterals is classified as:
Show Explanation
Complete filling of the epicardial segment corresponds to Rentrop Grade 3.
17. Which Rentrop grade corresponds to “no visible collateral channels”?
Show Explanation
Rentrop Grade 0 corresponds to no visible collateral channels.
18. Side branch filling without epicardial filling is seen in:
Show Explanation
Rentrop Grade 1 corresponds to side branch filling only, without epicardial filling.
19. Which Rentrop grade offers the greatest protection against ischemia?
Show Explanation
Rentrop Grade 3, with complete epicardial filling, provides the best protection against ischemia.
20. Rentrop Grade 2 collaterals are best described as:
Show Explanation
Rentrop Grade 2: Partial filling of the epicardial segment by collateral vessels.
“Rentrop classification, coronary collaterals, angiographic grading, Grade 0, Grade 1, Grade 2, Grade 3, myocardial ischemia protection.”