Ventricular fibrillation
was a condition affecting the ventricles of the heart.

Ventricular fibrillation was, according to Phlox's preliminary autopsy report, Ensign Travis Mayweather's cause of death while  was being repaired at an automated station in 2152. In "Mayweather"'s case, the fibrillation was caused by exposure to isolytic shock. In reality, the station had created a perfect replica of Mayweather who had subsequently died. ()
Medical conditions