Morphology of papillary muscles in human adults: A cadaveric study

Abstract

Introduction: The papillary muscles (PM) play an important role in ventricular overextension. The variability in the number, shape and location of papillary muscle of the right and the left ventricle is important for the surgeon in reparative procedures, papillary muscle dysfunction, mitral valve replacement and use of mitral valve homograft for mitral/tricuspid replacement. Materials and Methods: The study was conducted using 15 formalin fixed adult human hearts. The presence, number, shapes, length, number of additional heads of the papillary muscles were observed. The presence of moderator band (MB) was noted and its level of attachment to the anterior PM was observed. Results: Double anterior and posterior PM were found in few cases. The length of PM was longer in the left ventricle when compared to the right ventricle which was statistically significant. In the right ventricle cone-shaped PM was observed in the majority of the cases whereas flat topped PM was observed in 2 cases. In the left ventricle all the PM were cone shaped. In majority of the cases (N=13) the MB was attached to the lower third of the PM whereas in one case each it was attached to the upper third and to the middle third respectively. Conclusions: The morphology and morphometry of the papillary muscles of both ventricles and moderator band were defined. These may help cardiac surgeons during surgical procedures conducted for correction of their defects.