HYPERTROPHY - an increase in the volume and mass of an organ.
Distinguish between true and false hypertrophy. With false hypertrophy, an increase in the organ occurs as a result of increased development, for example, of adipose tissue, which is usually combined with atrophy of parenchymal elements. The basis of true hypertrophy is the reproduction (hyperplasia) of specifically functioning parenchymal elements of the organ. True hypertrophy often develops due to increased functional load on a particular organ (the so-called working hypertrophy). An example of such hypertrophy is the powerful development of muscles in people engaged in physical labor, athletes. In pathology, working hypertrophy develops under the influence of functional loads caused by any obstacles to the normal activity of an organ (tissue, cell), for example, cardiac muscle hypertrophy with increased blood pressure, heart valve defects, esophageal wall hypertrophy above the site of its cicatricial narrowing, etc. A type of working hypertrophy is vicar, or replacement, hypertrophy - an increase in one paired organ (for example, a kidney) when another or its insufficient function is removed.