Coronary Angiography: The "Gold Standard" Test
Coronary Angiography, also called a "Heart Cath," is an invasive imaging procedure that is the gold standard for diagnosing coronary artery disease (CAD).
It provides a detailed, real-time X-ray "movie" of your heart's arteries. This allows doctors to see the exact location and severity of any blockages or narrowing.
The Process: What to Expect
Preparation
- You will need to fast (not eat or drink) for several hours beforehand.
- Tell your doctor about all your medications (especially blood thinners) and any allergies, particularly to iodine or shellfish.
- A blood test will be done to check your kidney function, as your kidneys must clear the X-ray dye.
The Procedure
- You will be given a mild sedative to relax, but you will be awake. The access site (usually the wrist or groin) will be numbed.
- A tiny, flexible tube called a catheter is guided through your blood vessels up to your heart. You will not feel this.
- A special contrast dye is injected through the catheter. You may feel a brief, warm flushing sensation.
- A large X-ray machine moves around you, taking "movies" (angiograms) as the dye fills your arteries, revealing any blockages.
Immediate Treatment: One of the biggest advantages of an angiogram is that if a significant blockage is found, your doctor can often treat it *immediately* with an angioplasty (stent).
Why Is an Angiogram Needed?
An angiogram is not a first-line test. It's ordered when other tests (like a stress test or CT scan) suggest a high risk of a blockage, or if symptoms are severe.
- To definitively diagnose the location and severity of blockages causing angina (chest pain).
- As an emergency procedure during a heart attack to find and open the blocked artery.
- To evaluate heart valve disease or other structural problems before surgery.
- To get a clear answer when other tests are inconclusive.
Normal Flow
Stenosis (Narrowed)
Occlusion (Blocked)
Understanding Your Results: Stenosis
Normal Findings
A "normal" angiogram is great news. It shows smooth, wide-open arteries, with the contrast dye flowing freely.
Abnormal Findings (Stenosis)
The primary abnormal finding is stenosis, or a blockage from plaque. This is measured as a percentage:
- Mild Stenosis (< 50%): Generally not severe. Managed with medication and lifestyle changes.
- Moderate Stenosis (50-70%): A "gray area." Your doctor may do further tests to see if it's limiting blood flow.
- Severe Stenosis (> 70%): This is a "hemodynamically significant" blockage that limits blood flow and causes symptoms. It almost always requires treatment.
- Total Occlusion (100%): The artery is completely blocked.
Bypass Graft
How Doctors Provide Treatment
The angiogram results are the cornerstone for your treatment plan.
- Medical Therapy (for Mild Disease): If blockages are not severe, the focus is on aggressive management with statins (for cholesterol), aspirin, and lifestyle changes.
- Angioplasty & Stenting (PCI): If one or two significant blockages are found, your doctor can often perform this *during the same procedure*. A balloon opens the artery, and a stent is placed to hold it open.
- Bypass Surgery (CABG): Recommended for multiple severe blockages. A surgeon uses a healthy blood vessel from your leg or chest to create a "bypass" or a new route for blood to flow *around* the blockage.