Cardiac angiography is an invasive test that is performed to view the heart's vessels and diagnose narrowings and diseases related to the coronary arteries of the heart. Of course, in addition to examining the coronary arteries of the heart, the cavities of the heart and the main vessels related to the heart can also be observed.

The main tool of cardiac angiography is the angiography machine, which is the source of X-ray production. X-rays are used to perform many radiology images and CT scans. This ray passes easily in contact with the soft tissue of the body, but in contrast to the hard tissues of the body, depending on the type of tissue, it is absorbed by the tissue to different degrees and creates black areas in the created images. The heart and blood vessels are among the soft tissues that X-rays easily pass through and cannot create a specific image of the blood flow or the shape of the heart and blood vessels. For this purpose, injectable materials that can absorb X-rays are used. Basically, angiography is the injection of a contrast material into the veins and cavities of the heart and simultaneous imaging with X-rays to create an image of the same vein or cavity in the angiographic images. In this way, if there is a narrowing or blockage in the path of the heart's veins or cavities, the contrast material will not reach those areas, and therefore, an image of these areas will not be created.

To perform angiography, one of the available peripheral vessels is used, such as the "femoral" groin artery, or the "radial" wrist artery. Through this vein, long and hollow tubes called "catheters" are directed to the heart and the rest of the angiography work is done through these catheters.

There are many different types of catheters, each of which is used for a specific purpose. Routine catheters for angiography are approximately one meter long and 2 mm in diameter, but for special cases, different lengths and from 1 mm to 8 mm in diameter are also used.

In addition to angiography and injection of contrast material, it is possible to measure the pressure inside the heart cavities, the pressure inside the main arteries, the pressure of the pulmonary artery, measuring the pressure difference on both sides of the heart valves, congenital heart holes and also measuring the amount of oxygen in the blood in There are also heart cavities, which basically examine hemodynamics and heart function. The collection of these works is called "catheterization". In most cases, two procedures "angiography" and "catheterization" are performed together at the same time.