The jugular vein runs up the side of your neck.

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The phrase "go for the jugular" means to attack a vital, vulnerable part of someone or something. It refers to the jugular vein, which runs on both sides of the neck of a person or animal and returns blood from the head to the heart. Serious injury to the jugular can drain blood from the head and brain and lead to a quick kill.

For patients with heart disease, cardiologists now often go to the jugular for help in making diagnosis and treatment decisions.

Conventional wisdom has long linked swollen neck veins with the occurrence of heart disease. Nowadays, some cardiologists evaluate blood pressure in the jugular as a part of their physical exams of heart patients and use this information to make their diagnoses. When the blood pressure in the jugular vein is higher than normal, its walls can swell or distend, resulting in a condition known as jugular venous distension.

Cardiologists can estimate the blood pressure in the jugular vein (jugular venous pressure) by careful observation of the vein. This requires the patient to be lying down with the upper body at an angle of less than 30 degrees, with the neck muscles relaxed. The doctor usually observes the jugular vein from the side, aided by a beam of light shining on the patient's neck. From this perspective, he or she can observe the filling level of the jugular and estimate the blood pressure.

Cardiologists can also observe pulses in the jugular vein, called the jugular venous pulse. This is a source of information about the state of the right atrium, one of the chambers in the heart.

Analysis of jugular venous pressure and pulse provides information about physical aspects of the blood circulation in the right side of the heart and can be useful in the diagnosis of different forms of heart and lung disease. An elevated jugular venous pressure is the classic sign of right-sided heart failure.

On the next page, we'll find out what causes jugular venous distension and how it can result in fluid overload.