无害性杂音通常被认为产生于肺动脉,有时称为肺动脉收缩期喷射性杂音或肺动脉无害性收缩期杂音。心腔内心音图确亦证实在大多数正常人的肺动脉内可产生这种收缩期杂音,但是这些测定仅限于右心,不能排除胸壁听到的杂音系来自主动脉瓣的可能。一些正常人左心腔内心音图的研究,证实收缩期喷射性杂音确可产生于主动脉内。作者的实验显示动脉内记录到的杂音强度与血流的湍流强度呈线性关系,主动脉中的湍流强度比肺动脉大,故考虑这种无害性杂音可能来自主动脉,因而作了如下的观察。对10例无瓣膜病变而有心绞痛症状的 Harmful murmurs are commonly thought to originate in the pulmonary arteries, sometimes referred to as pulsatile systolic murmurs or nonsonic systolic murmurs of pulmonary arteries. Intracardiac phonocardiography also confirms that systolic murmur can be produced in most normal human pulmonary arteries, but these measurements are limited to the right heart and do not rule out the possibility of murmurs heard from the chest wall from the aortic valve. Some normal left ventricular endocardial tone study confirmed that systolic ejection noise can indeed be generated in the aorta. The authors’ experiments showed that there was a linear relationship between the intensity of the murmur recorded in the artery and the turbulence intensity of the blood flow, and that the intensity of the turbulence in the aorta was larger than that of the pulmonary artery. Therefore, considering that this innocuous murmur may come from the aorta, the following observations were made . 10 cases of valvular disease without angina symptoms