PFO Doubles Post-Surgical Stroke Risk

Patent foramen ovale (PFO) contributes to the risk for stroke within 30 days of non-cardiac surgery, according to a new study.

Researchers at Beth Israel Deaconess Medical Center (BIDMC; Boston, MA, USA), Brigham and Women’s Hospital (BWH; Boston, MA, USA), and other institutions conducted a retrospective cohort study involving 182,393 consecutive adults undergoing non-cardiac surgery with general anesthesia between January 1, 2007, and December 31, 2015. The main outcome was perioperative ischemic stroke occurring within 30 days of surgery; stroke subtype; and stroke severity.

The results revealed that 0.6% of the patients experienced an ischemic stroke within 30 days of surgery, with preoperative diagnosis of PFO significantly associated with an increased risk of ischemic stroke (3.2% versus 0.5%). Estimated risk of stroke was 5.9 for every 1,000 patients with a PFO, and 2.2 for every 1,000 patients without a PFO, an absolute risk difference of 0.4%. Patients with PFO also had an increased risk of large vessel territory stroke, and a more severe stroke-related neurologic deficit. The study was published on February 6, 2018, in JAMA.

“Stroke is a devastating post-surgical complication, and we have a new pathway with known treatments that potentially could be used to decrease the risk. Most patients do not know that they have a PFO before surgery,” said lead author Matthias Eikermann, MD, PhD, of the BIDMC department of anesthesiology. “Future studies will be helpful to see if performing routine echocardiography prior to surgery changes our surgical decision-making by specifically looking for and diagnosing a PFO before it contributes to stroke.”

When the chambers of a human heart begin to develop, a tunnel is formed between the right and left atria of the heart in order to allow blood to flow directly from the venous to the arterial circulation, circumventing the non-functioning fetal lungs. Following birth, a pressure differential between the right and left atria forms to allow blood flow to the fully functioning lungs, and the tunnel eventually closes completely. When this does not occur, a PFO is formed, allowing blood clots and deoxygenated blood to o cross over to the arterial side.

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Beth Israel Deaconess Medical Center
Brigham and Women’s Hospital