Original histologic findings in arteries of the right ventricle papillary muscles in human hearts.

In this study we describe original histologic findings of the right ventricle papillary muscle (PM) arteries in people under 30 years old. We examined 666 samples taken from the tip, mid-portion, and base of the PM in 56 males and 55 females, as well as samples from the rest of the right ventricle. The amount of smooth muscle cell (SMC) fibers in the tunica media (TM) led to their division into three groups: Group 1: 351 samples (53%); normal amount, normal lumen.