Concentric hypertrophy of left ventricle is seen in -

Concentric hypertrophy → In pressure overload, e.g. hypertension and aortic stenosis. Eccentric hypertrophy → In volume overload, e.g. in aortic regurgitation. Adaptations in heart The cardiac myocyte is a terminally differentiated cell that is not able to divide, Myocardium cannot undergo hyperplasia, i.e. an increase in the number of myocytes, So, myocardium can adapt by increasing the size (i.e. hypertrophy) of the myocyte in response to stress. There are two types of stresses to heart 1. Pressure overload Occur in hypertension or aortic stenosis. Pressure overloaded ventricles develop concentric hypertrophy of the left ventricle, with increased in wall thickness. Heart size may increase. The increase in wall thickness may reduce the cavity diameter —> ratio of cavity size to wall thickness decreases. There is an increase in the transverse diameter (width) of myocytes, but cell length remains the same. 2. Volume overload As occurs in aortic regurgitation  There is dilatation of ventricular chamber along with the increased thickness of ventricular wall Eccentric hypertrophy. There is increasing both in the transverse diameter (width) and the length of myocytes. It is due to deposition of the sarcomeres (functional intracellular contractile unit of cardiac muscles) in parallel to the long axis of cells.