Coronary angiography
Your coronary arteries visible with millimetre precision

Cardiac catheterisation is the umbrella term for all examinations of the heart performed via a catheter — including pressure measurements in the heart chambers and assessment of the heart valves. Coronary angiography is the part that specifically images the coronary arteries with contrast agent. Because this part is performed in almost every examination, the two terms are often used interchangeably in everyday language.

The two methods serve different purposes. CT coronary angiography is non-invasive and is particularly suited to reliably ruling out coronary artery disease when the likelihood is low to intermediate. Invasive coronary angiography is more accurate in heavily calcified arteries, allows a pressure-wire measurement and is the only method that allows treatment with a stent in the same session. Which method is right depends on your symptoms, previous test results and your risk profile.

The procedure itself usually takes 30 to 90 minutes. Including preparation and monitoring afterwards, you should plan to spend 4 to 6 hours at the clinic.

A narrowing is considered significant from about 70 per cent of the vessel diameter, and in the left main stem from about 50 per cent. For narrowings between 50 and 70 per cent, the image alone cannot reliably show whether blood flow is actually restricted — here a pressure-wire measurement (FFR or iFR) is decisive. The thresholds are based on the guidelines of the European Society of Cardiology.

In a pressure-wire measurement, an ultra-thin wire with a pressure sensor is passed through the narrowing. It measures how much the blood pressure drops beyond the narrowing. An FFR value of 0.80 or below, or an iFR value of 0.89 or below, indicates that the narrowing significantly restricts blood flow and that treatment is advisable. If the value is above this, medication is usually sufficient.

A diagnostic coronary angiography typically involves a dose of a few millisieverts. For comparison: natural background radiation in Switzerland amounts to around 5 to 6 millisieverts per year. We keep the fluoroscopy time as short as possible and document the dose of every examination. Where there is a clear medical indication, the diagnostic benefit clearly outweighs the radiation risk.

A purely diagnostic outpatient coronary angiography in Switzerland typically costs between CHF 2’000 and CHF 4’000. If a stent is implanted, the costs are between CHF 4’000 and CHF 9’000. Where there is a medical indication, the examination is a mandatory benefit of compulsory basic health insurance — you only pay your deductible (franchise) and co-payment.

Only if you have agreed to this beforehand and the findings clearly require it. We explain this possibility to you before the examination. For narrowings that clearly need treatment, treating them in the same session is usually the gentlest option. For complex findings — such as three-vessel disease — we first discuss the approach in the Heart Team.

At the Cardiance Group you do not need to fast. On the morning of the examination you can usually have a light breakfast and drink enough fluids. Take your regular medication as usual — the exception is blood thinners (aspirin may be taken as usual). If you have diabetes, you will receive individual instructions.

The term describes how many of the three main coronary arteries have significant narrowings: the left anterior descending artery (LAD, in German reports RIVA), the circumflex artery (RCX) and the right coronary artery (RCA). In one-vessel disease, stent treatment is usually the treatment of choice. In three-vessel disease or when the left main stem is involved, the Heart Team weighs up whether bypass surgery is the better long-term solution.