Hiroshima University May 10 2025 Tempted to skip the floss? Your heart might thank you if you don't. A new study from Hiroshima University (HU) finds that the gum disease bacterium  Porphyromonas gingivalis  ( P. gingivalis ) can slip into the bloodstream and infiltrate the heart. There, it quietly drives scar tissue buildup-known as fibrosis-distorting the heart's architecture, interfering with electrical signals, and raising the risk of atrial fibrillation (AFib). Clinicians have long noticed