Coronary angiography and angioplasty
Coronary angiography is a test which is undertaken to assess a patient's coronary arteries. There are a number of reasons that this test may be considered appropriate, but the 2 most common are;

Angina - if the cardiologist considers a diagnosis of angina possible, based on your history and any appropriate previous tests, an angiogram may the appropriate test to investigate your coronary arteries and consider treatment (medicines, angioplasty or cardiac surgery)

Prior to cardiac surgery - if you have a significant valve problem and your cardiologist has recommended a surgical procedure to repair or replace this valve, it is normal practice to undertake an angiogram prior to the surgery to ensure that the cardiac surgeon has all the necessary information about your heart prior to the operation.
Prior to the procedure
Access to the arterial system
Angiography
Angioplasty and other assessments
After the procedure