In normal individuals, the external jugular vein is often unremarkable in the upright or sitting position and may be slightly filled but not pulsating, with the level of filling limited to the lower 1/3 of the distance from the superior clavicle to the angle of the jaw. If the degree of filling exceeds the normal level in position, or if the filling of the vein is evident in the standing and sitting position, it is called jugular vein anger. It is indicative of increased superior vena cava pressure and is seen in heart failure, constrictive pericarditis, pericardial effusion or obstruction of superior vena cava reflux, and significant jugular pulsation (systolic pulsation) can be seen in tricuspid valve closure insufficiency. Carotid pulsations should be distinguished from jugular venous pulsations; the former pulsations are coarser, distending, and can be seen and palpated, while the latter pulsations are soft and diffuse in extent, and can be seen but not palpated. The jugular venous reflux sign is more pronounced in patients with right heart failure when the enlarged liver is pressed, which is called positive jugular venous reflux sign, and is one of the important signs of right heart failure and may also be seen in exudative or constrictive pericarditis. Mechanism of occurrence: Due to pressure on the stagnant liver, the blood flow back to the inferior vena cava and right atrium increases, but the jugular vein fills up more significantly because the right atrium is stagnant or the right ventricle is restricted in diastole and cannot fully accept the blood flow back. If a vascular murmur is heard in the large-vessel region of the neck, carotid or vertebral artery stenosis should be considered, which is usually evident during systole. If a murmur is heard in the supraclavicular fossa, it may be a stenosis of the subclavian artery, seen in cervical rib compression. If a continuous camp-like venous sound is heard in the right supraclavicular fossa, it may be produced by the jugular vein flowing into the wider caliber bulb of the superior vena cava, which is physiological and disappears after compression of the jugular vein with the fingers.