The guidelines for delaying non-heart-related surgery six weeks after a bare-metal stent and one year after a drug-eluting may be overly cautious. The delays currently recommended after drug-eluting stent placement may need to be reevaluated by the experts who develop the guidelines for clinicians, based on a new study published in Journal of the American Medical Association.

A stent is a wire mesh tube that’s inserted into a narrowed coronary artery to prop it open, prevent re-blockage and allow the heart muscle to get the blood flow and oxygen it needs. 

For patients who have had surgery after stents, the biggest risk is stent clotting. If that happens, the patient could have a major heart attack and die, said lead author Mary Hawn, M.D., MPH, FACS.

“The guidelines recommend delaying surgery in patients with drug-eluting stents for at least 12 months over concern of stent-related complications with reducing or stopping anti-platelet medications,” said Hawn, who is also professor and chief of Gastrointestinal Surgery at the University of Alabama at Birmingham and staff surgeon at the Birmingham VA Medical Center.

She said the scientific evidence is building in favor of  a minimum of a six-month wait prior to surgery after placement of either stent type.  Hawn and colleagues analyzed data from nearly 125,000 Veterans Administration patients who received a stent between 2000 and 2010. Almost a quarter of the group had an operation that wasn’t heart-related within two years. Within 30 days, 4.7 percent had a major heart event, with surgery within six months adding to the risk. But no significant effect was seen after six months.

Hawn said that one of the biggest risk factors to consider is whether the patient had a heart attack before surgery.

“Other cardiac risk factors such as insulin dependent diabetes, kidney insufficiency, congestive heart failure and the magnitude of the planned surgical procedure all contributed to the risk of having a heart attack after surgery,” Hawn said.  “These factors should be strongly considered by the patient together with their surgeon, cardiologist and anesthesiologist when planning surgery following a coronary stent placement.”

The authors point out that the study, which mostly contained elderly men, may not be fully applicable to women or younger patients.