If it's a simple... if it's a simple thing like what's the differential for aortic stenosis, i. e. injection systolic murmur, there's just four points here.

如果这是一个简单的......如果这是一个简单的内容，比如主动脉狭窄的鉴别诊断，即注射收缩期杂音，这里只有四个要点。

Aortic stenosis murmur is loudest in the aortic area and the sound radiates to the carotid arteries in the neck following the direction of blood flow.

主动脉瓣狭窄杂音在主动脉区域声音最大，杂音随着血流的方向放射至颈部的颈动脉。

Concentric hypertrophy leading to diastolic failure can also be caused by aortic stenosis, which is a narrowing of the aortic valve opening, as well by hypertrophic cardiomyopathy, an abnormal ventricular wall thickening often from a genetic cause.

导致舒张性心衰的向心性肥大，也可能由主动脉瓣狭窄（即主动脉瓣开口变窄）造成，也可能由肥厚型心肌病（一种遗传性异常心室壁增厚）引起。