- A Visual Guide to Heart Disease
- Medical Illustrations of the Heart Image Collection
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- Patient Comments: Cardiology - Diagnosis
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- Patient Comments: Angioplasty and Stents - Prognosis
- Patient Comments: Coronary Angioplasty and Stents - Experience
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- Coronary balloon angioplasty and stents facts
- What is balloon angioplasty?
- How does coronary artery disease develop?
- How is coronary artery disease diagnosed?
- What medications treat coronary artery disease?
- What are the complications of percutaneous coronary intervention?
- How long is the recovery time after after percutaneous coronary intervention?
- What are the long-term results of percutaneous coronary intervention?
Quick GuideHeart Disease: Symptoms, Signs, and Causes
How is coronary artery disease diagnosed?
The resting electrocardiogram (EKG, ECC) is a recording of the electrical activity of the heart, and can show changes indicative of ischemia or heart attack. Often, the EKG in individuals with coronary artery disease is normal at rest, and only becomes abnormal when heart muscle ischemia is brought on by exertion. Therefore, exercise treadmill or bicycle testing (stress tests) are useful screening tests for those with significant coronary artery disease (CAD) and a normal resting EKG. These stress tests are 60% to 70% accurate in diagnosing significant coronary artery disease.
If the stress tests are not diagnostic, a nuclear agent (Cardiolite or thallium) can be given intravenously during stress tests. Addition of one of these agents allows imaging of the blood flow to different regions of the heart, using an external camera. An area of the heart with reduced blood flow during exercise, but normal blood flow at rest, signifies substantial artery narrowing in that region.
Stress echocardiography combines echocardiography (ultrasound imaging of the heart muscle) with exercise stress testing. It is also an accurate technique for detecting coronary artery disease. When a significant narrowing exists, the heart muscle supplied by the narrowed artery does not contract as well as the rest of the heart muscle. Stress echocardiography and thallium stress tests are 80% to 85% accurate in detecting significant coronary artery disease.
When a person cannot undergo an exercise stress test because of neurological or arthritic difficulties, medications can be injected intravenously to simulate the stress on the heart normally brought on by exercise. Heart imaging can be performed with either a nuclear camera or echocardiography.
Cardiac catheterization with angiography (coronary arteriography) is a technique that allows X-ray pictures to be taken of the coronary arteries. It is the most accurate test to detect coronary artery narrowing. Small hollow plastic tubes (catheters) are advanced under X-ray guidance to the openings of coronary arteries. Iodine contrast "dye" is then injected into the arteries while an X-ray video is recorded. Coronary arteriography gives the doctor a picture of the location and severity of narrowed artery segments. This information is important in helping the doctor select medications, percutaneous coronary intervention, or coronary artery bypass graft surgery (CABG) as the preferred treatment option.
A newer, less invasive technique is the availability of high speed CT coronary angiography. While it still involves radiation and dye exposure, no catheters are needed in the arterial system, which does decrease the risk of the procedure somewhat. This modality has a more limited role, in that, it is less questionable than conventional angiography and cannot allow PCF to be done the same time. It is important to remember that the risk of serious complications from conventional coronary angiography is very low (well under 1%).