What characterizes idiopathic hypertrophic subaortic stenosis (IHSS)?

Idiopathic hypertrophic subaortic stenosis (IHSS) is primarily characterized by hypertrophy of the left ventricle. This condition commonly occurs in the interventricular septum, leading to a thickening that can obstruct the outflow tract of the left ventricle to the aorta during systole. The hypertrophic muscle can create an abnormal interaction with the aortic valve, which can lead to symptoms such as chest pain, syncope, and in some cases, sudden cardiac death. The presence of this hypertrophy is a key diagnostic feature in ultrasound imaging, and it significantly affects cardiac function by increasing the stiffness of the left ventricle and reducing its ability to fill. Thus, a focus on the left ventricular hypertrophy is crucial in understanding the pathophysiology of IHSS.