A renal angiogram or renal arteriogram is an imaging study of the arteries which supply the kidneys with blood. This type of imaging study is ordered when a patient is experiencing kidney problems or is believed to be at risk of a kidney disorder. It takes place in a hospital or clinic with angiography facilities, and the length of time required for the procedure varies. Patients are usually encouraged to arrange for a ride home after the procedure, as they may feel groggy.
There are a number of reasons to request a renal angiogram. A doctor may suspect that the veins are stenosed or blocked, or that a ballooning known as an aneursym is occurring. Tumors could be pressing on the blood supply and interrupting it, and other kidney problems might be leading to alterations in the vessels which supply the kidneys with blood. A renal angiogram may also be ordered if a patient has hypertension, to learn more about the cause of the high blood pressure.
During the angiography procedure, the patient lies on a table while a catheter is inserted through the groin to access the renal artery so that contrast material can be injected. Images are taken with a fluoroscopy machine for real time imaging, or with an x-ray for still images. The patient is usually given medications which will help him or her stay calm and still during the procedure, especially if the patient has a history of discomfort and restlessness during medical procedures.
The contrast dye will highlight the blood vessels on the renal angiogram. In a procedure known as digital subtraction angiography, a computer removes other structures in the image such as bones so that the network of blood vessels can be very clearly seen. Examining the renal angiogram, a doctor can identify areas of abnormality which indicate the need for intervention, such as stenting to open an occluded renal artery, or surgery to address a tumor on the kidneys.
This procedure can be contraindicated for some patients. Patients with blood which is slow to clot can be in danger because the procedure causes bleeding and there is also a risk of rupturing a vessel. For pregnant women, any procedure requiring radiation is not recommended unless it is absolutely necessary because radiation can hurt the developing fetus. People with allergies may also be at risk during a renal angiogram, because they may react to the contrast agent. Patients should be sure that doctors know their full clinical history before consenting to a procedure.