FDA Warns Intravascular Device Coatings May Separate

By Jof Enriquez,
Follow me on Twitter @jofenriq

The U.S. Food and Drug Administration (FDA) has issued a safety communication warning physicians that hydrophilic and/or hydrophobic coatings on several types of intravascular medical devices could separate and cause serious injury or death to patients.

The safety communication says that hydrophilic and hydrophobic lubricious coatings [e.g., polyvinylpyrrolidone (PVP), polytetrafluoroethylene (PTFE), silicone, etc.] in intravascular catheters, guidewires, balloon angioplasty catheters, delivery sheaths, and implant delivery systems, could possibly separate (e.g., peel, flake, shed, delaminate, slough off), and cause injury to patients.

According to the FDA, since Jan. 1, 2010, there have been 11 recalls from various manufacturers associated with device coatings peeling or flaking off. The majority of devices were guidewires, but sheaths, retrieval devices, and embolization device delivery wires were also subject to recalls.

Since January 1, 2014, the agency says it has received 500 Medical Device Reports (MDRs) where coatings of devices – primarily vascular guidewires – had separated, including 11 MDRs involving patient deaths. MDRs and medical literature described serious adverse events, including pulmonary embolism, pulmonary infarction, myocardial embolism, myocardial infarction, embolic stroke, tissue necrosis, and death. Serious injuries recorded were related to persistent coating fragments, adverse tissue reactions, and thrombosis.

In the safety communication, FDA did not identify specific medical device brands or manufacturers that are higher-risk for coating separation, whose cause is described as "multi-factorial," including device design, device manufacturing, and manner of use. The agency notes that hydrophilic and hydrophobic lubricious coatings in devices have been in use for 20 years in millions of patients undergoing minimally invasive cerebrovascular, cardiovascular, and peripheral vascular procedures, and that it believes the overall benefit of using these devices continue to outweigh the risks.

A previous report by The Hospitalist cites a Mayo Clinic study suggesting that hydrophilic coating on endovascular devices could cause stroke or death. Dr. Alina Bridges, of the Department of Dermatology at Mayo Clinic in Rochester, Minn., cautioned, “While the use of polymer-coated devices offers several advantages, clinicians must be aware of their potential complications, including stroke, myocardial and pulmonary infarction, gangrene, and/or death.”

Medical device coatings possess wetting characteristics that serve a lubricating function, thereby improving maneuverability in device insertion/withdrawals, decreasing intravascular trauma, and minimizing the risk for thrombosis. Devices with these coatings have allowed the use of more minimally invasive procedures over more invasive ones that are associated with longer recovery times and higher infection risk, according to the FDA.

However, the agency says coating separation could happen because of a number of factors, "ranging from the difficulty of the procedure and the patient’s anatomy to practitioner technique or using the wrong device for the procedure, to improper preconditioning of the device and improper storage conditions, as well as issues with device design or manufacturing processes."  

FDA recommends that healthcare providers take the following precautions to reduce the risk of adverse events, reports Medscape:

1. Be aware that many devices are designed, labeled, and indicated for specific uses.
2. Follow manufacturer instructions for proper device storage.
3. Review manufacturer instructions on how to use two devices together properly.
4. Follow the manufacturer's recommendations on preconditioning, which activates the lubricious properties of device coatings.
5. Use only the recommended solution for preconditioning.
6. Avoid using alcohol, antiseptic solutions, or other solvents to pretreat the device. Avoid presoaking the device longer than instructed. Avoid wiping the device with dry gauze.
7. Use caution when manipulating, advancing, and/or withdrawing these devices through needles, metal cannulas, stents, or other devices with sharp edges, or through tortuous or calcified blood vessels.
8. Be aware that attempting to alter the shape of devices by bending, twisting, or similar methods may compromise the coating integrity, and that damage to the coating may not always be noticeable to the naked eye.
9. Replace the device if it does not move freely, is visibly kinked or otherwise damaged, or does not perform as expected.
10. Contact the manufacturer for more information on device safety.