Cardiac catheterisation What is cardiac catheterisation and what can it show? Cardiac catheterisation is a procedure that is used to study the right side of the heart. It is also known as right-heart catheterisation. Cardiac catheterisation can provide accurate information about the blood pressure in the heart and pulmonary artery. It is used to confirm the diagnosis of pulmonary hypertension (PH) and confirm or exclude some causes of PH. Cardiac catheterisation How is cardiac catheterisation done? If you are having a cardiac catheterisation procedure you will need to stay in hospital for a few days. During cardiac catheterisation you lie still while a catheter (a long, thin, flexible tube) is inserted into a vein in your groin or neck and fed through to your pulmonary artery. During the procedure you are connected to an electrocardiogram (ECG) machine and also have your blood pressure and oxygen levels in your blood monitored. The catheter can be used to take blood samples from different parts of the circulatory system. The cardiac catheterisation measurements section describes the important measurements taken using cardiac catheterisation. Watch a video of a cardiac catheterisation, taken from the Pulmonary Hypertension Association (PHA UK) DVD Understanding Pulmonary Hypertension – a guide to diagnosis and treatment, here.