The following day, Lewis checked into New England Baptist Hospital, where he underwent a series of tests by more than a dozen heart specialists, who the Celtics called their "dream team" of doctors. Lewis was diagnosed with "focal cardiomyopathy", a disease of the heart muscle that can cause irregular heartbeat and heart failure. Lewis was told his condition was most likely career-ending. However, he later sought a second opinion from Dr. Gilbert Mudge at Brigham and Women's Hospital, who diagnosed Lewis with neurocardiogenic syncope, a less serious non-fatal condition instead. As a result, Lewis began working out in preparation for returning for the 1994 season. Mudge was later cleared of any wrongdoing, and he insisted he had never authorized Lewis to resume workouts.