In Angiography, a long wire called catheter is inserted inside the artery of the leg, near the thigh crease. This catheter is then pushed against the blood flow towards the heart blindly. With a view of the tip of the catheter on the fluoroscopy monitor (which exposes the patient to very heavy radiation) this catheter is pushed onwards by trial and error method. If it gets stuck somewhere on the route, it is withdrawn a little and again pushed in. Not only it scratches the whole length of the arterial tubes of the body but it can also puncture any corner of the tubes. Once the tip reaches the heart area, further manipulation is done to push the tip in one of the coronary arteries. Once inside the coronary tube, after a lot of trial and error, a radioactive dye is injected through the hole in the catheter inside the coronary tubes and further fluoroscopy photographs are taken.
The tip of the catheter is again withdrawn, negotiated inside another coronary tube and the same photos are taken.
If the dye seems to fill up the coronary tubes completely, the blockages are probably not there. It the dye can not fill the tubes (as roughly seen in the photos taken) inside, it is taken as filling defect and indirectly interpreted as blockages. The viewer mostly puts a rough percentage.
This report, being an eye estimation is given as 70%, 80% and so on. It varies from one viewer to another. It also depends on the timing of the photograph (best is before the dye is washed out), angle of the photograph etc. and is thus amenable to lot of different reports. It is not at all accurate and thus given in variations of 10%. One of my patients came to me the other day and told me that in the last two days he has already reversed his heart blockage by 10%. I asked “By what method”?. He said- “the second cardiologist told me that the blockage was 70%. Till now it was 80% according to the first cardiologist!”
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