What kind of accident is the instrument failure in the heart stent surgery?

The owner of the so-called instrument failure, I think it should be DSA equipment (digital subtraction angiography machine), this kind of large-scale equipment failure will not be considered medical malpractice, as you said the armpit on the syringe, it should be the retention of arterial sheaths, which is touched in the handling of the patient's way may cause some puncture point damage, serious aneurysm, if the patient wants to claim compensation, can only start from this aspect, but I think this lawsuit is very difficult to win, because the consent form will often end with a clause such as "the occurrence of unexpected or difficult to resist". If the patient wants to claim compensation, he can only start from this aspect, but I think it is difficult to win this lawsuit, because there is often a clause at the end of the surgical consent form, such as "the occurrence of unforeseen, or irresistible ........." How so and so, that equipment failure can be attributed to that.