Pressure behind the breastbone when you climb the stairs quickly, easing again once you rest: that is classic angina pectoris. Many of those affected assume that a cardiac catheterisation must now follow straight away. In most cases that is not so. Whether an invasive examination of your coronary arteries makes sense depends on the severity of the symptoms, the calculated risk and the results of non-invasive tests. This article sets out when the catheter is really needed and when a calmer route leads to the goal.
When does angina pectoris require a cardiac catheterisation?
Invasive coronary angiography, the classic cardiac catheterisation, is not an automatic first step in stable angina pectoris. The guideline of the European Society of Cardiology recommends it above all when the clinical likelihood of a relevant narrowing is very high (over 85 percent), when symptoms persist despite optimal medication, when angina occurs even at low levels of exertion, or when non-invasive tests show a high risk of events [Vrints 2024]. At low to intermediate likelihood, a non-invasive test comes first, usually cardiac computed tomography of the coronary arteries [Vrints 2024]. The large ISCHEMIA comparison with over 5000 participants also showed that in stable disease an immediately invasive strategy did not lower the risk of heart attack or death over several years compared with initial treatment by medication alone [Maron 2020]. The catheter therefore clarifies the situation and prepares a treatment. It is not a blanket reassurance.
What happens in the body during angina pectoris?
Angina pectoris is a symptom rather than a disease in its own right. It arises when the heart muscle briefly receives too little oxygen, usually because a coronary artery has been narrowed by arteriosclerosis. During exertion the demand for oxygen rises, the narrowed vessel cannot supply enough, and the muscle makes itself felt with pressure or tightness [Schweizerische Herzstiftung].
Typical features:
- pressure, burning or tightness behind the breastbone
- possible radiation into the arm, neck, jaw or upper abdomen
- triggered by physical or emotional strain
- relief within a few minutes at rest
The distinction matters. If the symptoms last longer than around 15 minutes, occur at rest, or are accompanied by shortness of breath, nausea and cold sweat, an acute heart attack may be behind them. Every minute then counts, and in Switzerland you should dial 144, the national emergency number, immediately.
Chest pain also does not always originate in the large coronary arteries. In some of those affected, more often in women, the cause lies in the small vessels or in a dysfunction of the vessel wall. An unremarkable view of the large arteries therefore does not mean the symptoms are imagined.
The path to diagnosis: non-invasive first
Before a catheter is even up for discussion, the cardiology team estimates your pre-test probability. Age, sex, the nature of the symptoms and risk factors such as smoking, high blood pressure, diabetes and elevated LDL cholesterol all count towards this.
- Clinical assessment: Medical history, risk profile and estimated pre-test probability determine the next steps.
- Non-invasive imaging: At low to intermediate likelihood, cardiac CT of the coronary arteries is the preferred first procedure to rule out a relevant narrowing [Vrints 2024].
- Functional evidence of ischaemia: Stress echocardiography or stress MRI show whether a narrowing actually leads to impaired blood flow.
- Invasive coronary angiography: Only with persistent symptoms despite therapy, angina at low exertion or high-risk findings does the catheter become the targeted next step.
This sequence has a practical advantage. It avoids procedures where imaging has already given the all-clear, and it ensures that a narrowing found during catheterisation is genuinely relevant to blood flow. If the likelihood is very high and symptoms occur even at low exertion, the route shortens and the invasive examination moves forward [Vrints 2024].
What the catheter can do and what it cannot
Invasive coronary angiography is considered the most precise view of the anatomy of the coronary arteries. A thin catheter is guided to the heart via the wrist or the groin, and contrast agent makes the vessels visible on the X-ray image. With experienced teams and access via the radial artery, serious complications are below one percent [Brueck 2009].
The decisive point: a visible narrowing of 50 to 70 percent does not automatically have to be treated. For this reason, with moderate stenoses the function is measured directly in the vessel, using fractional flow reserve (FFR) or the instantaneous wave-free ratio (iFR). Values of 0.80 or below (FFR) or 0.89 or below (iFR) indicate a flow-limiting stenosis that may benefit from dilatation [Vrints 2024]. If the values are above these thresholds, treatment can safely be deferred [Davies 2017].
Symptoms alone do not justify dilatation. In the placebo-controlled ORBITA trial, stent treatment did not measurably improve exercise duration in stable angina more than a sham procedure once medication had been optimised [Al-Lamee 2018]. A stent can relieve symptoms. It never replaces consistent basic therapy.
What happens if the catheter shows a narrowing?
| Finding | Possible course of action |
|---|---|
| no relevant stenosis | medication, lifestyle, no intervention |
| single flow-limiting stenosis | percutaneous coronary intervention with stent (PCI) |
| complex multivessel disease or left main stem | consider bypass surgery in the heart team |
In every case, secondary prevention remains the foundation: a statin to lower LDL, blood pressure control, an antiplatelet agent where appropriate, plus stopping smoking, exercise and a Mediterranean diet. These measures slow the progression of coronary disease, regardless of whether a stent was placed [Vrints 2024]. In our experience, reliable medication adherence and regular check-ups contribute more to the long-term outcome than the question of whether a single stent was placed.
How we proceed at Dein Team Herzzentrum
We first calculate your individual risk and use non-invasive imaging in a targeted way before an invasive step comes up for discussion. If a cardiac catheterisation makes sense, we discuss the benefits, the procedure and the alternatives openly, and you share in the decision. A cardiology assessment can usually be arranged at short notice, often within a few days and without a referral. In Switzerland, outpatient cardiology services are billed under the TARDOC tariff, the national fee schedule for outpatient care. This overview does not replace a personal cardiological evaluation.
Frequently asked questions
Will I always have a cardiac catheterisation for angina pectoris? No. In stable angina with low to intermediate likelihood, a non-invasive work-up comes first, usually cardiac CT of the coronary arteries. The catheter follows only at high risk or with persistent symptoms despite therapy [Vrints 2024].
Does a cardiac catheterisation with a stent lower my risk of a heart attack? In stable coronary heart disease, the ISCHEMIA trial showed no advantage over several years of an immediately invasive strategy compared with initial medical treatment in terms of the risk of heart attack or death [Maron 2020]. An intervention can, however, relieve symptoms and is clearly indicated for certain high-risk findings.
How dangerous is the examination? Invasive coronary angiography is very safe in experienced hands. Via the radial artery, serious complications are below one percent [Brueck 2009]. Possible risks are bleeding at the puncture site, reactions to the contrast agent and a small dose of radiation.
What is FFR and why is it measured? Fractional flow reserve measures directly in the vessel whether a visible narrowing genuinely restricts blood flow. A value of 0.80 or below indicates a relevant stenosis. This avoids unnecessary dilatations [Davies 2017].
Can a narrowing be treated without a stent? Yes. Many stable narrowings are well controlled with medication and lifestyle adjustments. In the ORBITA trial, a stent brought no measurable additional benefit for exercise capacity when medication was optimally adjusted [Al-Lamee 2018].
What happens if the catheter is unremarkable? An unremarkable result rules out a relevant narrowing of the large vessels and provides reassurance. If the symptoms persist, we investigate microvascular causes, which affect the small vessels and are detected with functional tests.
When is chest pain an emergency? If pressure or pain lasts longer than around 15 minutes, occurs at rest, or is accompanied by shortness of breath, nausea and cold sweat, a heart attack may be present. In Switzerland the rule is: dial 144 immediately [Schweizerische Herzstiftung].