In the practice of cardiologists, cardiovascular and endovascular surgeons, we can find the patients with abnormalities, when the coronary arteries underneath the muscle layer of the myocardium. They are called “myocardial bridge”. When stents are installed in myocardial bridges, stents in most cases broken. The reason for the stent fracture was most often associated with the force that the bridge presses on the arteries, but the reason was the fatigue of metal of the stent. The aim of study was to assess the fatigue strength of stent metals in a reconstructed model of a myocardial bridges.

First step, the strength of the myocardial bridge pressure was measured in a patient who had clinical manifestations of coronary artery disease, which was 0.012 N /mm. A test bench was recreated that simulates the cyclic loads of the"myocardial bridge" with the pressure force which we have measured. For the study, we used 2 types of stents from different manufacturers. The stents put in a PTFE tube and placed between two supports. The results of the experiment were registered on a USB camera every 30 minutes.

In the first stent, metal fracture was noted after 16 days from the start of installation. To speed up the experience cyclic loads were increase, which in real conditions, with a normal heart rate, match to 41 days. The second stent was functioning more than 2 months, during this time we didn’t register any defects in the stent.

Experience has shown that the fatigue strength of stent metals varies from different manufacturer. Consequently, the stent product under cyclic loading may have a limited life time, which must be considered in the case of stenting of these areas. The device can be used in research and development to assess the strength characteristics of coronary stents.