Class III Medical Devices (EU MDR)

The European Union Medical Device Regulation (EU MDR) is a new set of rules that will apply to medical devices marketed in the European Union to ensure the quality and safety of the medical device.

According to Article 51 of the MDR, medical devices are classified according to their intended purpose and inherent risks into four groups, class I, IIa, IIb and III. The 22 classification rules are listed in the Annex VIII of the MDR Act. The classification is based on four factors, the duration of contact of the device, the degree of invasiveness, the anatomy affected, and whether the device is active or otherwise. The regulatory requirements for the devices vary according to their inherent risk, with stricter regulations for the devices posing a higher risk to the patient.

Class III devices carry the highest risk and are often in contact with vital organs like the heart and the central nervous system

Most of the medical devices included in class III are invasive devices. The only non-invasive devices included in this group are those that contain substances that are brought in contact with human cells, or even the fetus, in vitro, and are later intended to be introduced into the body.

Surgically invasive devices in contact with the heart, the central circulatory system or the central nervous system are classified under class III devices, irrespective of their duration of use. The central circulatory system includes the the aorta, pulmonary artery, the common, internal and external carotid arteries, the coronary and the cerebral arteries, the coronary veins, the brachicephalicus trunk, the pulmonary veins and the superior and inferior vena cavae. The central nervous system includes the brain and spinal cord, and their surrounding membranes, the meninges.

These surgically invasive devices may include those for transient use like:

  • Neuroendoscopes, brain spatulas, direct stimulation cannulas, spinal cord retractors, spinal needles, angioplasty balloon catheters, stent delivery catheters/systems, including guidewires, introducers and dedicated disposable cardiovascular surgical instruments e.g. electrophysiological catheters, electrodes for electrophysiological diagnosis and ablation.
  • Catheters containing or incorporating sealed radioisotopes, where the radioactive isotope is not intended to be released into the body, if used in the central circulatory system

Surgically invasive devices intended for short-term use included in class III are:

  • Neurological catheters, cortical electrodes, cardiovascular catheters, cardiac output probes, temporary pacemaker leads, thoracic catheters intended to drain the heart and the pericardium, carotid artery shunts, and ablation catheter.

Surgically invasive devices intended for long-term use included in class III are:

  • Prosthetic heart valves, aneurysm clips, vascular prosthesis and stents, central vascular catheters, spinal stents, CNS electrodes, cardiovascular sutures, permanent and retrievable vena cava filters, septal occlusion devices, intra-aortic balloon pumps and external left ventricular assisting devices.

Other surgically invasive devices included in class Iii are:

  • Absorbable sutures, breast implants, surgical meshes; total or partial joint replacements or spinal disc replacement implants
  • Devices that have a biological effect in the body when used over short or long-term like adhesives are also classified under class III devices.
  • Long-term devices classified under class III include the following:
    • Those intended to undergo chemical change, except if the devices are placed in the teeth
    • Those intended to administer medicinal products
    • Active implantable devices or their accessories, or implantable devices that come into contact with the spinal column with the exception of ancillary components such as screws, wedges, plates and instruments
    • Software intended to provide information which is used to take decisions with diagnosis or therapeutic purposes, if such decisions have an impact that may cause death or an irreversible deterioration of a person’s state of health
    • All devices incorporating integral medicinal product, including a medicinal product derived from human blood or human plasma, and that has an action ancillary to that of the devices
    • Intrauterine contraceptive devices, including those that release hormones.
    • All devices manufactured utilising tissues or cells of human or animal origin, or their derivatives, which are non- viable or rendered non-viable, unless they are intended to come into contact with intact skin only.
    • All devices incorporating or consisting of nanomaterial that present a high or medium potential for internal exposure  
    • Devices that are composed of substances or of combinations of substances that are intended to be introduced into the human body via a body orifice or applied to the skin and that are absorbed by or locally dispersed in the human body:
    • if they, or their products of metabolism, are systemically absorbed by the human body in order to achieve the intended purpose
    • if they achieve their intended purpose in the stomach or lower gastrointestinal tract and they, or their products of metabolism, are systemically absorbed by the human body
    • Active therapeutic devices with an integrated or incorporated diagnostic function which significantly determines the patient management by the device, such as closed loop systems or automated external defibrillators
    • All active devices that are intended for controlling, monitoring or directly influencing the performance of active implantable devices.

This article is for informational purposes only and not intended to replace the relationship between the doctor and the patient. It should not be used for self-treatment by patients or by doctors to treat patients. Consult your doctor before using any of the above information.


Published on 9/9/2020

Copyright: InsiWi Solutions LLP