Van Doren was an individual who was largely responsible for establishing a successful cardiac replacement procedure. By 2365, this technique had been perfected to a very low 2.4% mortality rate.
That year, while en route to have the procedure performed on him, Jean-Luc Picard mentioned the low mortality rate of Van Doren's technique to Wesley Crusher. (TNG: "Samaritan Snare")
This character was only mentioned in dialogue.