Cath lab equipment:
- Xray equipment
- Pressure transducer head
- Operators
- Nurses
- Radiographer
Indications for cardiac catheterisation:
- Stable/unstable angina
- Positive exercise tolerance test/ non-invasive test
- Pre-operative assessment
- Myocardial infarction (STEMI/NSTEMI)
- Salvage post established infarct
- Cardiogenic shock (measured using central pressure and kidney function)
- Valvular heart disease – assessment and treatment
- Congenital heart disease – assessment and treatment
- Pericardial constriction/ tamponade
- Transplantation status (evidence of rejection)
Contraindications – absolute
- Inadequate equipment/ personal
Contraindications – relative
- Pregnancy
- Pre-existing renal dysfunction (contrast is nephrotoxic)
- Electrolyte imbalance
- Unknown anticoagulation status (measure anticoagulation time or INR for warfarin)
- Uncontrolled heart failure (excessive pulmonary oedema, arrhythmias)
- Uncooperative patient
Potential complications:
- Death (1.1 per 10000)
- Stroke (6 per 10000)
- Pericardial tamponade
- MI
- Emergency bypass surgery
- Vascular dissection (intima is torn – not as severe as a perforation)
- Pseudoaneurysm
- Cardiac perforation and tamponade
- Contrast reaction (anaphylaxis, nephrotoxicity)
- Thrombosis, embolus, air embolus
- Heart block
- Significant haemorrhage
- Vasovagal reactions (patients would have fainted if they weren’t laying down)
, - Radiation injury (e.g. in total chronic occlusion)
In cardiac catheterisation, a sheath is typically placed in the radial or femoral artery/ vein under
sterile conditions using the seldinger technique. Catheters are introduced into the vessel via the
sheath and advanced into the aorta or vena cava.
The catheters are attached to a wheatstone bridge transducer which gives pressure readings. This
transducer converts physiological measurements into proportional waveforms which can be
evaluated. This transducer must be level with the heart, adequately calibrated, and zeroed.
Seldinger technique
Lidocaine is given to numb the area. Needle is inserted to see if blood if pulsatile and bright red
(arterial). 038 wire then inserted. Needle is withdrawn, sheath and dilator are introduced. Dilator
and wire taken out, catheter can be inserted.