Last updated on 16th Oct 2021 - By Dwayne Michaels

How Abnormal BUN affects heart?

A recent multicentre cohort study demonstrated that high blood urea nitrogen (BUN) levels were associated with poor cardiovascular (CV) outcomes in patients with compensated heart failure (HF) and reduced left ventricular ejection fraction (LVEF).

Blood test

Blood urea nitrogen (BUN) is a medical test that measures the amount of urea nitrogen found in blood. The liver produces urea in the urea cycle as a waste product of the digestion of protein. Normal human adult blood should contain 6 to 20 mg/dL (2.1 to 7.1 mmol/L) of urea nitrogen.

Urea nitrogen is a normal waste product in your blood that comes from the breakdown of protein from the foods you eat and from your body metabolism.

Consult a doctor

It is normally removed from your blood by your kidneys, but when kidney function slows down, the BUN level rises. BUN can also rise if you eat more protein, and it can fall if you eat less protein.

A BUN test can help diagnose the conditions such as dehydration, malnutrition, liver damage, urinary tract obstruction, poor circulation, gastrointestinal bleeding and congestive heart failure.

Individual laboratories will have different reference ranges of Blood Urea Nitrogen (BUN) as the assay used can vary between laboratories. The test is used to detect renal problems. It is not considered as reliable as creatinine or BUN/creatinine ratio blood studies.

The main causes of an increase in BUN are: high protein diet, gastrointestinal hemorrhage, decrease in glomerular filtration rate (GFR) (suggestive of kidney failure), rapid cell destruction from infections, decrease in blood volume (hypovolemia), congestive heart failure, fever, athletic activity, excessive muscle breakdown, and increased catabolism.

You may need a BUN test for other reasons too. Depending on your overall health, it may be part of a routine health check to find out how your kidneys are working.

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If you need dialysis or medicine for kidney function, you may have the test to check the health of your kidneys before the procedure, after the procedure, or both. BUN tests are also routine during hospital stays for certain conditions.

A BUN test may be done with a blood creatinine test. The level of creatinine in your blood also tells how well your kidneys are workinga high creatinine level may mean your kidneys are not working properly.

Blood urea nitrogen (BUN) and creatinine tests can be used together to find the BUN-to-creatinine ratio (BUN:creatinine). A BUN-to-creatinine ratio can help your doctor check for problems, such as dehydration, that may cause abnormal BUN and creatinine levels.


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