Routine blood tests

Glucose

This test measures the level of glucose (sugar) in the blood. If this is ≥ 6mmol/l further investigation may be required to determine the cause.
Baseline results are useful for future clinical management.

Cholesterol profile (HDL, LDL)

Cholesterol is a fatty substance (lipid), which is essential to keep the body healthy. Cholesterol is produced naturally within the body – mainly in the liver. Excess saturated fat in the diet and, in some cases, genetic factors increase blood cholesterol. Recommended (or target) levels depends on cardiovascular risk and presence of existing cardiovascular disease.
LDL (low-density lipoprotein) is known as “bad cholesterol“. It carries cholesterol from your liver to the tissues around your body.
HDL (high-density lipoprotein) is known as “good cholesterol” because it carries surplus cholesterol from the tissues back to your liver to be recycled or excreted. The recommended HDL level is above 1.0mmol/l (men) and above 1.2mmol/l (women).
Currently, there are different protocols / working practice across Scotland (It is recommended that you familiarise yourself with your local guidance). “Normal” and “target” levels are reviewed when guidelines, including SIGN, are updated.

Liver function tests

Liver function tests (LFT”s) measure various chemicals in the blood made by the liver. An abnormal result indicates a problem with the liver, and may help to identify the cause. Further tests may be needed to clarify the cause of the liver problem. LFT’s are reported including the following common values:

• Bilirubin: 3-17Umol/l
• Alanine aminotransferase (ACT) 5-35iu/L
• Aspartate Transaminase (AST) 5-35iu/L
• Alkaline Phosphatase (ALP) 30-150iu/L (non pregnant)
• Albumin 30-50g/l
• Protein 60-80g/l

Thyroid function (TFT’s)

Thyroid levels can affect the healthy heart, so is a test commonly performed if patients present with symptoms, particularly tachycardia (fast pulse), bradycardia (slow pulse) or other arrhythmias.
The most common tests are

• TSH – Thyroid Stimulating Hormone : 0.4-4.5mU/L
• FT4 – Free T4 (the active part of thyroxine): 9-25 pmol/L
• FT3 – Free T3 (the active part of triiodothyronine): 3.5-7.8pmol/L

Urea & electrolytes (U’s & E’s)

Urea levels help to monitor how the kidneys are working. Electrolytes (e.g. sodium, potassium) and minerals (e.g. calcium) help to stabilise the heart rhythm.
These include;

• Sodium (NA) 135-145 mmol/L
• Potassium (K) 3.5-5mmol/L
• Creatinine 70-150 Umol/L
• Urea 2.5-6.7 mmol/L

EGFR is Estimated Glomerular Filtration Rate, usually based on:serum Creatinine level, age, sex, and race.

Troponin

Troponin is a protein which is released into the blood stream when the heart muscle is damaged. The troponin level provides a quick and accurate measure of any heart muscle damage. It is used to help diagnose acute coronary syndromes and may need to be taken on admission to hospital and / or 12 hours from the onset of symptoms. Reference values are dependent on many factors, including patient age, gender, sample population, and test method. Numeric test results can have different meanings in different labs.
Test results are usually considered normal if the results are:

• Troponin I : less than 10 ┬Ág/L
• Troponin T : 0-0.1 ┬Ág/L

Other cardiac enzymes are also affected by damage to the heart, including creatinine kinase (CK) and natriuretic peptides (ANP/BNP).

Full blood count (FBC)

This measures the level of red, white blood cells and platelets. It also measures haemoglobin (HB), the oxygen carrying component of red blood cells. Any reduction in haemoglobin can reduce the oxygen travelling to the coronary arteries and increase problems to the healthy heart.

• Red blood cells: Adult woman: 3.8 to 5 x 10 12/l (3.8 to 5 million per cubic millimeter of blood)
  Adult Man 4.5 to 6.5 x 10 12/l (4.5 to 6.5 million per cubic millimeter of blood)
• Haemoglobin (Hb) Adult Woman 11.5 to 16.5 grams per 100ml of blood
  Adult Man 13 to 18 grams per 100ml of blood
• White blood cells Adult Woman and Adult man 4 to 11 x 10 9/l (4,000 to 11,000 per cubic millimeter of blood)
• Platelets (thrombocytes) Adult Woman & Man 150 to 440 x 10 9/l (150,000 to 440,000 per cubic millimeter of blood)