LAD, RCA and LCX are the main heart arteries named in every CT angiography report. Learn what each artery supplies and how to read your report.
A CT coronary angiography report uses short names for the heart arteries. LAD is the left anterior descending artery, LCX is the left circumflex artery, and RCA is the right coronary artery. The left main artery splits into LAD and LCX. Each artery supplies a part of the heart muscle, so a blockage in one affects a particular region.
The Left Main and LAD
The left main (LM) artery is short and supplies a very large part of the heart. A narrowing here is important and is often treated with bypass surgery. The LAD runs down the front of the heart and is the most commonly blocked artery. It is divided into proximal, mid and distal segments. Blockages in the proximal LAD affect a large area. See CAD-RADS report explained.
ArteryFull nameArea suppliedLMLeft mainDivides into LAD and LCX; supplies a large part of the heartLADLeft anterior descendingFront wall of the left ventricle and the septumLCXLeft circumflexSide and back wall of the left ventricleRCARight coronary arteryRight side of the heart and often the bottom wallBranchesDiagonal, obtuse marginal, PDASmaller branches off the main arteriesThe Circumflex and Right Coronary Arteries
The LCX supplies the side and back of the left ventricle through branches called obtuse marginals. The RCA supplies the right ventricle, the heart's natural pacemaker area and, in most people, the bottom wall through the posterior descending artery (PDA). The artery that supplies the PDA decides "right dominant" (most people) or "left dominant" circulation.
How Stenosis Is Reported
- Percentage narrowing: mild under 50, moderate 50 to 69, severe 70 or above (left main 50 or more is significant).
- Plaque type: calcified, mixed or soft. See coronary plaque types.
- Segment names, such as proximal, mid, distal.
- Special notes on stents, bridges or anomalies.
Reading a Sample Line
A line such as "mid LAD 60 percent mixed plaque" means that, in the middle part of the LAD artery, there is a moderate narrowing of about 60 percent with both calcified and soft plaque. It does not mean you have a heart attack. Your cardiologist will decide on tests and treatment. See CTCA report time and next steps.
What To Do With Your Report
Keep a copy of the report and images. Ask your cardiologist to explain each artery in your own report, the CAD-RADS score and the treatment plan. Understand which medicines you take and why. Repeat tests only when advised.
A Practical Example
Hari, 55, has a CTCA report that says "proximal RCA 40 percent calcified plaque; LAD and LCX normal". His cardiologist explains that this is mild disease in the right artery, advises a statin, daily walking and diet changes and plans a repeat check after a year. Understanding the names helped him follow the plan.
Key Facts at a Glance
- LAD, LCX and RCA are the three main heart arteries
- The left main divides into LAD and LCX
- Segments and percentages tell where and how much narrowing
- Your cardiologist decides the plan
After the Scan and Next Steps
Take the report to a cardiologist and ask to see the images. Share it with any other doctor treating you. Heart-healthy habits help all three arteries: daily walking, balanced food, no tobacco and good control of sugar, blood pressure and cholesterol. Report chest pain, breathlessness or fainting early.
Questions to Ask Your Doctor
- Which of my arteries have plaque and how much?
- What is my CAD-RADS score?
- Is my left main artery normal?
- What treatment will protect each artery?
Common Mistakes to Avoid
- Comparing your report with someone else's.
- Ignoring mild plaque.
- Stopping medicines when you feel well.
Booking, Timing and Report
Book a morning slot if possible, since fasting is easier. Carry your doctor's prescription, previous heart and blood reports, a recent creatinine report and a medicine list. Allow 45 to 90 minutes at the centre. Reports are usually ready within 24 to 48 hours, because vessel images need careful review.
Frequently Asked Questions
What does LAD stand for?
Left anterior descending artery.
What does RCA stand for?
Right coronary artery.
What is LCX?
Left circumflex artery.
What is the left main?
The artery that divides into LAD and LCX.
Which artery is most often blocked?
The LAD.
What does 60 percent stenosis mean?
A moderate narrowing.
What is dominance?
Which artery supplies the bottom wall of the heart.
Is mild plaque serious?
It needs prevention, not panic.
When is the report ready?
Usually 24 to 48 hours.
Book Your Test at Ganesh Diagnostic
Ganesh Diagnostic & Imaging Centre in Rohini, Delhi offers this test with trained radiology staff and clear reports. You can book an appointment online, check our branches across Delhi NCR, contact us for current rates, or explore all our services. Reports can be downloaded online through our patient portal, so you do not need to make a second trip just to collect them.
This article is for general information only. It does not replace advice from your doctor. Always follow your doctor's instructions for your test.
Related Reading
- Foods That Help Lower Heart Plaque Risk
- CT Left Atrial Appendage Scan Before Closure
- Myocardial Bridging on CT Angiography
- CT Coronary Angiography Before Redo Bypass Surgery
- Spontaneous Coronary Artery Dissection (SCAD) on CT
- Coronary Artery Anomalies on CT Angiography
- CT Renal Angiography for Kidney Artery Disease
- Heart Attack Warning Signs and When to Get Tested
