Comparative Morphology of Papillary Muscles of the Right and Left Atrioventricular Valvular Apparatus of the Human Heart

Background: The papillary muscles (PMs) have a significant role in ventricular overextension. The knowledge of variations in the number, shape, and grouping pattern of PM of the right and the left ventricle is useful for the surgeons in dealing with reparative procedures, PM dysfunction, and use of valve homograft for the valve replacement surgeries. Hence, familiarity with the variability of PMs is crucial in guiding surgical interventions and improving the success of various cardiac procedures. Aims and Objective: To study the morphology of PMs of the right and left atrioventricular valvular apparatus of the human heart. Subjects and Methods: The study was carried out on 100 formalin-fixed hearts of both genders of all ages. PMs were observed on the basis of number, shape, and grouping. Results: In the current review, the frequency of PM was found to be between 2 and 4 in both the right and left atrioventricular valves. Three types of shapes of PM were observed, i.e. conical, pyramidal, and broad. Conical-shaped PMs were more frequently present on the left side than on the right side. PMs were also divided on the basis of their grouping pattern. They showed single-, two-, and multiple-head grouping patterns. Conclusion: No two-valve complexes have the same architectural arrangement, as each individual’s heart seems to be distinct. This highlights the need for conducting future large-scale research across the world to derive a better understanding of morphological variations. This will enable the cardiothoracic surgeons to conduct the surgical procedures according to the unique PM pattern of the individual patient.