The patient is taken to the cardiac catheterization laboratory where angiography is done. ECG and Spo2 (apparatus showing % oxygen in blood) monitoring cables are attached. Antiseptic medicine is applied at the wrist (if angiography is to be done through radial route) or at the upper part of thigh (if angiography is to be done through femoral route) and patient is covered with a linen drape.
After injecting 2 ml of lidocaine (local anesthesia), a 4-6 inch long plastic sheath in the radial artery through a small hole. A catheter of 1.5 – 1.75 mm diameter is passed through this sheath under fluoroscopic guidance (by looking at the monitor like a TV screen) and is taken up to the heart. Then day (a colourless, thick fluid like castor oil) is injected through the catheter in the right and left coronary arteries of the patient and a picture (movie) is obtained.
The entire process is almost painless and gets completed within 2 -5 minutes with least risk.