In an interview Tuesday on the NFL Network show "Total Access," fellow linebacker Willie McGinest said Bruschi needs treatment for a hole in his heart. The Boston Globe and Boston TV station WCVB also reported that Bruschi has the defect.
Bruschi met with doctors, WCVB reported, and is home awaiting surgery, which he likely will undergo at Massachusetts General Hospital.
The Patriots have not discussed Bruschi's medical status, referring all inquiries to his family. Bruschi's family has yet to comment publicly. When contacted by the Globe, a spokeswoman for Mass General referred all questions to the Patriots.
WCVB reported that Bruschi first learned of the hole in his heart during his hospital stay Feb. 16. According to the Globe, doctors said a hole in his heart could be an important clue why Bruschi -- a 31-year-old Pro Bowl player in the prime of his career -- had a stroke. The stroke caused numbness, blurred vision and severe headaches.
At the time, experts said Bruschi's return to the NFL would depend on the stroke's cause and severity. A mild stroke isn't necessarily a career-ending event for a professional athlete, but the risk is higher for someone who takes the punishment of an NFL linebacker.
Doctors pointed to Bruschi's quick release from the hospital, along with reports that he was walking and talking normally a day after the stroke, as hopeful signs that he may be able continue his career. Still, his prognosis remains uncertain because all strokes cause some level of brain damage and can raise fears of a recurrence.
"There really is no good stroke," said Dr. Larry Brass, a professor of neurology, epidemiology and public health at the Yale University School of Medicine.
According to specialists interviewed by the Globe, a hole in the heart can allow small blood clots that otherwise would be absorbed in the lungs to pass from one chamber of the heart to another, and then travel to the brain. Clots would be harmless elsewhere in the body but in the brain can become wedged in narrow vessels, blocking blood flow and causing a stroke.
"It's a very common explanation for why young people have strokes," Dr. David Thaler, director of the Tufts Comprehensive Stroke Center at Tufts-New England Medical Center, told the Globe.
Information from The Associated Press was used in this report.