Synopsis
Use invasive angiography and haemodynamic catheterisation when results will change treatment, while reducing access, bleeding, kidney and radiation harm.
- Coronary angiography defines lumen anatomy but does not show plaque biology or prove that an intermediate stenosis causes ischaemia.
- Use FFR or a validated non-hyperaemic pressure ratio to assess intermediate lesions before revascularisation when functional significance is uncertain.
- Radial access usually reduces access-site bleeding and permits earlier mobilisation, but anatomy and procedure may require femoral access.
- Before the procedure review indication, alternatives, consent, renal function, blood count, coagulation, allergies and all antithrombotic medicines.
- Right-heart catheterisation measures pressures, cardiac output and shunt data when non-invasive assessment is insufficient for a decision.
- New chest or back pain, hypotension, neurological deficit, limb ischaemia or enlarging access swelling after catheterisation is an emergency.
- A normal angiogram in a patient with angina can redirect assessment toward vasospasm or microvascular dysfunction rather than proving symptoms are non-cardiac.
Key red flags
Acute occlusion with an ACS presentation requires immediate reperfusion strategy and antithrombotic management.
Persistent bleeding, expanding haematoma, hypotension or falling haemoglobin requires compression, resuscitation and urgent vascular assessment.
Back or flank pain, hypotension and unexplained anaemia after femoral access may occur without obvious groin swelling.
Oliguria, acute neurological deficit, coronary dissection, no-reflow or limb ischaemia requires prompt targeted escalation.