The balloon dilatation technique applied in the coronary vessels, also called "Percutaneous Transluminal Coronary Angioplasty", or short PTCA, is based on the fact that angiostenosis of the coronary vessels is mostly caused by deformable material (e.g. deposition of blood lipids and cell components). The material hindering the blood flow can be expanded by means of the balloon dilatation.

Above all, balloon dilatation is performed in case of short narrowed areas or obstructions of the coronary vessels. Thanks to the remarkable technological progress in this medical field in recent years it is meanwhile possible to also help patients with several narrowed areas of the different coronary vessels by treating them with a balloon dilatation, which formerly was feasible only with a bypass surgery.

For the widening of a narrowed coronary vessel by means of a small balloon a purpose-build balloon catheter is introduced via a thin guide wire into the artery of the groin or the bend of the elbow. The balloon catheter is advanced along the guide catheter through the vascular system and the left ventricle until it has reached the narrowed areas of the coronary artery.

A few millimeters behind the tip of the balloon catheter there is an inflatable stiff balloon which is inserted into the narrowed area in slackened condition. As soon as the balloon has been placed inside the narrowing, is is unfolded for some seconds by applying high pressure. This serves to deform and squeeze the obstructing tissue cells and deposits. However, the vessel expansion is achieved, not only by a deformation of the deposits causing the narrowing but also by an outward expansion of the entire coronary vessel. The blood flow is thus improved or re-established. The success of this treatment is verified after dilatation by means of a radiographic contrast medium.