The main blood test for heart risk is a lipid panel (or lipid profile), which measures total cholesterol, LDL, HDL and triglycerides. It can be done fasting or non-fasting depending on local practice. Alongside this, doctors often check blood glucose or HbA1c to screen for diabetes, and may check kidney and thyroid function, as these affect heart risk and treatment choices.
These results are not judged in isolation. They are combined with your blood pressure, age, smoking, weight and family history to estimate your overall cardiovascular risk and guide whether lifestyle changes or medication are needed.
If you have a family history of early heart disease, high blood pressure, diabetes, or are over a certain age, ask your doctor whether you should be tested. A doctor or pharmacist can explain your results and what they mean for you. Note that separate blood tests called troponin are used in hospital to diagnose a heart attack, not for routine risk screening.