Computed Tomography (CT) Coronary Angiography is the latest non-invasive test, which has created a lot of hope for the heart patient. This is a simple test, there is no admission required. You just lie down on the table, one injection will be given and the table moves in such a way that your chest is inside a round circle. The scan now takes about one minute and the test is over. CT angiography will be able to tell your level of blockage and where they are situated.
This test is a little expensive (about Rs 10000/-) but is almost as accurate as the catheter coronary angiography. This test can be repeated after one or two years to know the reversal of blockages. This test has come to India 12 years back and many people are not aware of this test. Until now the machines are available only in metro cities. This is one of the tests, which have no side effects, and Saaol recommends this test to many.
This test has created a major problem for the heart hospital cardiologists as it competes with their own catheter angiography. They are not happy with this test.
The main reason is that the patient comes to know of the blockages without admission in the hospital and they cannot be pressurized for the angioplasty or bypass surgery. Usually, after the catheter angiography, the cardiologists prevail upon the admitted patients; put pressure on them and the relatives and make them agree for such treatment, which gives a lot of money. On public demand, many hospitals have installed this machine as more people want to know about their condition from outside. But you talk to the cardiologist in the same hospital; they will not encourage you to undertake this test.
If you ever see the report of an angiography you will find the blockages are all in round figure 70%, 80% and 90%. These are all my estimations. Blockages cannot jump from 70 % to 80%. They can also be 77.92% or 82.30% if you measure them accurately- which is possible (quantitative angiography). Most of the hospitals only do a qualitative angiography and give the report roughly. The reports vary from cardiologist to cardiologist even if they see the same CD records of angiography. Many of the cardiologists knowingly estimate the blockages as more, to create pressure for the treatment.
Advantages of CT Coronary Angiography
- Heart and vascular CT angiography can detect narrowing or obstruction of blood vessels allowing potentially corrective therapy to be done.
- CT angiography may give more precise anatomical detail than other tests, particularly in small blood vessels.
- Many patients can undergo heart and vascular CT angiography to diagnose blood vessel problems.
- Heart and vascular CT angiography is faster, non-invasive.
- CT Angiography is a useful way of detecting arterial (such as narrowing of blood vessels in the heart) and venous disease, as well as structural abnormalities of the heart before there are symptoms or when symptoms are not clearly related to blood vessel disease.
- There is also potentially less discomfort because contrast material is injected into an arm vein.
- No radiation remains in a patient’s body after heart and vascular CT angiography.
- X-rays used in standard CT scans have no immediate side effects.
Shortcomings of CT Coronary Angiography
- In some people especially aged (above 75 years) if calcium score is very high CT will not be a very good tool to exactly predict the percentage of blockage.
- If the heart rate is very high (above 80 beats per minute) normal CT scan cannot be done. So, patients need medicines to reduce the heart rate below 70 per minute or use dual-source CT scan which can successfully carry on scanning even if the heart rate is above 100 per minute.