A hole in the heart may increase the risk of stroke after non-cardiac surgery

New research published in the Journal of the American Medical Association suggests a patent foramen ovale (PFO), colloquially known as a hole in the heart, can double the risk of stroke within 30 days of non-cardiac surgery.

“Perioperative stroke is a major postoperative complication, with significant implications on postoperative morbidity, discharge disposition and 30-day mortality,” wrote lead author Matthias Eikermann, MD, PhD, Beth Israel Deaconess Medical Center in Boston, and colleagues. “With a reported incidence ranging from 0.2 to 9.7 percent for patients undergoing different surgeries and possibly even higher incidence of covert strokes, the estimated annual global burden of perioperative stroke could exceed one million.”

The researchers sought to determine whether a preoperatively diagnosed PFO increases risk of perioperative ischemic stroke. Using a retrospective cohort study from Massachusetts General Hospital and two affiliated community hospitals between 2007 and 2015, researchers studied the cases of more than 182,000 consecutive adults who underwent non-cardiac surgery with general anesthesia.

Of the more than 150,000 patient cases used for analysis in the final study cohort, researchers noted that a total of 1,540 patients had a PFO diagnosis before surgery and 850 ischemic strokes occurred within 30 days of surgery. In adjusted analysis, the researchers noted patients with PFO had an increased risk of ischemic stroke compared to patients without.

“An important finding from this study was that the PFO-attributable risk of perioperative stroke was highest among patients with an otherwise low probability of perioperative ischemic stroke based on coexisting cardiovascular risk factors and intraoperative characteristics,” the authors wrote. “This is in line with most previous studies in non-perioperative cohorts with cryptogenic stroke, which showed that the significance of PFO in increasing the risk for stroke is higher in patients younger than 55 years with cryptogenic stroke.”

The study showed PFO-related strokes were likely large-vessel territory strokes and strokes with severe neurologic deficits. PFO-related patients experienced an excess of perioperative complications due to systemic embolism. The authors noted their research data supports increased vulnerability to thromboembolic complications in patients with PFO during the perioperative period.

“Among adult patients undergoing non-cardiac surgery at three hospitals, having a preoperatively diagnosed PFO was significantly associated with increased risk of perioperative ischemic stroke within 30 days after surgery,” the authors concluded. “Further research is needed to confirm these findings and to determine whether interventions would decrease this risk.”