Cholesterol and Cardiac Testing Examples

Below you will find cholesterol and cardiac testing sample results with explanations, relevant ranges, and potential interpretations. Note that there are often minor differences in the reference ranges of the cardiac tests depending on the laboratory that performs the analysis.

How Do You Interpret Apolipoprotein B (Apo-B) Results?

This test measures the level of apolipoprotein B (apo-B), a protein that is a primary component of LDL cholesterol (bad cholesterol) and VLDL cholesterol. Apo-B is a factor in the development of atherosclerosis (narrowing of the arteries due to plaque buildup).

Elevated levels of apo B correspond to elevated levels of LDL-C and to non-HDL-C and are associated with an increased risk of cardiovascular disease (CVD). Elevations may be due to a high-fat diet and/or decreased clearing of LDL from the blood.

Some genetic disorders are the direct (primary) cause of abnormal levels of apo B. For example, familial combined hyperlipidemia is an inherited disorder causing high blood levels of cholesterol and triglycerides. Abetalipoproteinemia, also called Apolipoprotein B deficiency or Bassen-Kornzweig syndrome, is a very rare genetic condition that can cause abnormally low levels of apo B.

Abnormal levels of apo B can also be caused by underlying conditions or other factors (secondary causes). Increased levels of apo B are seen, for example, in:

  • Diabetes
  • Use of drugs such as: androgens, beta blockers, diuretics, progestins (synthetic progesterones)
  • Hypothyroidism
  • Nephrotic syndrome (a kidney disease)
  • Pregnancy (levels increase temporarily and decrease again after delivery)

Apo B levels may be decreased with any condition that affects lipoprotein production or affects its synthesis and packaging in the liver. Lower levels are seen with secondary causes such as:

  • Use of drugs such as: estrogen (in postmenopausal women), lovastatin, simvastatin, niacin, and thyroxine
  • Hyperthyroidism
  • Malnutrition
  • Reye syndrome
  • Weight reduction
  • Severe illness
  • Surgery
  • Cirrhosis
  • An increased ratio of apo B to apo A-I may indicate a higher risk of developing CVD.

How Do You Interpret B-Type Natriuretic Peptide (BNP) Test Results?

The B-Type Natriuretic Peptide (BNP) blood test measures the level of BNP, an amino acid polypeptide secreted by the heart. The BNP blood test is used to help diagnose heart failure and to determine the severity of that heart failure. Following is a sample of the results of the B-Type Natriuretic Peptide.

The report you receive from the laboratory or from your doctor will show your measured level of BNP or NT-proBNP. This is often measured in picograms per milliliter (pg/mL) but may be listed by some labs in nanograms per liter (ng/L) or picomoles per liter (pmol/L).

Along with your BNP or NT-proBNP level, the test results will include the reference range, which represents the expected levels in a healthy adult. The reference range may vary slightly among laboratories. Check your test report for the reference range and the units used by the lab.

How Do You Interpret C-Reactive Protein Highly Sensitive (CRP-hs) Test Results?

CRP is a protein that increases in response to inflammation or infection. There are 2 types of CRP tests. A standard test looks for very high levels of inflammation. The highly sensitive test can detect levels of CRP that are mildly high, which can be associated with atherosclerosis (narrowing of the arteries due to plaque buildup).

Although “normal” CRP levels vary from lab to lab, it is generally accepted that a value of 0.8-1.0 mg/dL (or 8-10 mg/L) or lower is normal. Most healthy adults have CRP levels lower than 0.3 mg/dL.

A minor elevation in CRP level—generally 0.3 to 1.0 mg/dL—does not necessarily mean you have an illness that requires treatment. CRP levels may be higher in females, patients on hormone replacement therapy, and those with high body mass index. Mildly elevated CRP can be associated with insomnia and depression. Your doctor will consider these factors when interpreting your CRP test result.

A CRP level higher than 1.0 mg/dL usually suggests that there is inflammation in your body, but it does not identify the cause or the location of that inflammation. Very high levels of CRP can be associated with various types of infections, autoimmune diseases, some cancers, and conditions affecting the lungs or pancreas. If your CRP level is in this range, your doctor may order additional tests before making a diagnosis.

How Do You Interpret Creatine Kinase (CPK,CK) Test Results?

Creatine kinase is a protein that your muscles need in order to function. Levels of CK can become elevated due to muscle damage, heart attack, exercise, alcohol consumption or from certain medications or supplements. If muscle damage is suspected from an injury, this test may be ordered multiple times as it may take 48 hours for the CK level to rise.

CK-MB is normally undetectable or very low in the blood.

Chest pain and increased CK levels plus elevated CK-MB indicate that it is likely that a person has recently had a heart attack. Levels that drop, then rise again may indicate a second heart attack and/or ongoing heart damage.

If CK-MB is elevated and the ratio of CK-MB to total CK (relative index) is more than 2.5-3, then it is likely that the heart was damaged. A high CK with a relative index below this value suggests that skeletal muscles were damaged.

Any kind of heart muscle damage can cause an increase in CK and CK-MB, including physical damage from trauma, surgery, inflammation, and decreased oxygen (ischemia). Strenuous exercise may also increase both CK and CK-MB, but usually with a lower relative index.

Kidney failure can cause a high CK-MB level.

Rarely, chronic muscle disease, low thyroid hormone (T3, T4) levels, and alcohol abuse can increase CK-MB.

How Do You Interpret Homocysteine Test Results?

Homocysteine is an amino acid in your blood that our bodies use for energy production. Homocysteine levels are strongly influenced by your diet, as well as by genetic factors. Studies have shown that high levels of homocysteine in the blood are related to an increased risk of coronary heart disease, stroke, Alzheimer’s disease and osteoporosis.

In cases of suspected malnutrition, vitamin B12 or folate deficiency, homocysteine levels may be elevated. If an individual does not get enough B vitamins and/or folate through diet or supplements, the body may not be able to convert homocysteine to other forms that can be used. In this case, the level of homocysteine in the blood can increase.

Studies from the mid- to late-1990s suggested that people with elevated homocysteine levels have a much greater risk of heart attack or stroke than those with average levels. Investigating the link between high homocysteine levels and heart disease remains an active area of research.

At present, however, the use of homocysteine levels for risk assessment of cardiovascular disease (CVD), peripheral vascular disease, and stroke is uncertain, given that several trials investigating folic acid and B vitamin supplementation indicate no benefit or lowering of CVD risk.

Additionally, a 2012 study of multiple datasets, including 50,000 people with coronary heart disease, called the potential for a cause-and-effect relationship between homocysteine levels and heart disease into question.

A 2015 review of studies concluded that although there is a relationship between homocysteine and CVD, there is other evidence that precludes homocysteine in being considered a biomarker for the disease. The American Heart Association (AHA) does acknowledge the relationship between homocysteine levels and heart attack/stroke survival rates but doesn’t consider elevated homocysteine an independent risk factor for CVD.

While the AHA does not recommend the widespread use of folic acid and B vitamins to reduce risk of heart attack and stroke, it does promote a balanced, healthy diet. It advises health care practitioners to consider overall risk factors and diet in managing cardiovascular disease.

You may want to ask your doctor the following questions:

  • Could any medications I may be taking affect my homocysteine level?
  • What are some good sources of folic acid and vitamins B6 and B12?
  • Are there any follow-up tests I should do?

How Do You Interpret Lipid Panel Results?

The lipid panel blood test measures cholesterol in your body. The lipid panel specifically measures your total cholesterol, triglycerides, high density lipoproteins (HDL also called “good cholesterol”), low density lipoproteins (LDL also called “bad cholesterol”), and very low-density cholesterol (VLDL).

The results of your lipid panel are reported for each type of cholesterol and triglycerides. These are measured in milligrams per deciliter of blood (mg/dL).

The optimal or target level for each part of the standard lipid test are listed below:

  • Total cholesterol: Below 200 mg/dL
  • HDL (good) cholesterol: Above 60 mg/dL
  • LDL (bad) cholesterol: Below 100 mg/dL (For people with diabetes: Below 70 mg/dL)
  • Triglycerides: Below 150 mg/dL

Values that do not meet these targets may be classified as borderline-, intermediate-, or high-risk. In general, higher-than-target levels of total cholesterol, LDL, and triglycerides and lower-than-target levels of HDL can heighten the risk of cardiovascular problems.

Test results are interpreted in the context of your overall health and other risk factors. Many doctors use special risk calculators that incorporate your test results, age, and other factors to determine the most appropriate next steps.

Continued cholesterol monitoring, lifestyle changes, and/or medications may be recommended to lower cholesterol and decrease cardiovascular risk, but there is not a universal consensus about when these types of interventions are optimal.

Cholesterol-lowering medications, such as a class of drugs called statins, are most likely to be recommended for patients with very high LDL or elevated LDL combined with other risk factors such as diabetes or past cardiovascular problems.

Abnormally low levels of cholesterol are rare and usually associated with a health condition causing malnutrition.

If you have risk factors for heart disease or abnormal lipid levels, repeat testing may be conducted at regular intervals in the future. Your doctor can recommend a schedule for future testing.

If your lipid levels are normal, you may not need repeat testing for another five years unless your overall health or risk factors change.

In some cases, other types of cholesterol testing, such as direct LDL testing, may be needed if you have high levels of triglycerides. While not included in the standard lipid panel, expanded lipid measurements, such as LDL particle testing, may be ordered. Additional types of tests, such as a cardiac stress test, may also be considered as part of an overall cardiovascular risk assessment.

If you take a point-of-care or at-home test that shows abnormal cholesterol levels, it is common to have follow-up testing done by a laboratory.

When reviewing your test results with your doctor, some questions that may be helpful include:

  • What are my risk factors for cardiovascular disease?
  • What do my test results show about my cardiovascular health?
  • Have my lipid levels changed over time?
  • Do I need any follow-up tests? When should I have another cholesterol test?
  • Are any treatments recommended based on my test results? What are my treatment options and their benefits and risks?

Lipoprotein(a) Results

The Lipoprotein (a) test measures the amount of Lipoprotein (a) in your blood. Lipoprotein(a) is a particle in your blood that carries proteins, fats, and cholesterol. Since Lp(a) is a genetic condition, if one individual has a high level of Lp(a), then the family should be checked as well.

Depending on the laboratory method used, lipoprotein (a) levels are reported in milligrams per deciliter (mg/dL) of blood or in nanomoles per liter (nmol/L) of blood.

The laboratory method can also affect the reference range for lipoprotein (a), so look closely at the test report to see the range of lipoprotein (a) levels considered normal for the specific laboratory that performed your test. Your doctor can review the results with you and explain whether they were normal or abnormal.

High lipoprotein (a) levels are considered a potential contributor to cardiovascular problems like the buildup of plaque in the arteries, heart attack, and stroke. In general, lipoprotein (a) levels above 50 mg/dL or 125 nmol/L are considered high risk for cardiovascular disease, heart attack and stroke.

Lipoprotein (a) levels are determined primarily by genetics and generally cannot be changed by diet or medication. However, if you have very high levels of lipoprotein (a) you may be advised to take more aggressive measures to lower your levels of “bad” LDL cholesterol.

Interpreting a lipoprotein (a) test result requires considering many factors, including your age, results from other cholesterol tests, additional risk factors for cardiovascular disease, and your overall health. Your doctor is in the best position to review these considerations and explain the significance of your lipoprotein (a) test result.

After a lipoprotein (a) test, you can discuss the results with your doctor. The following questions may help you understand the test result:

  • What was my lipoprotein (a) level?
  • Does my lipoprotein (a) test result change how you evaluate my cardiovascular disease risk?
  • Do you recommend any additional testing?
  • Are there any medications or lifestyle changes you recommend based on my lipoprotein (a) and other cholesterol levels?

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