Cardiac catheterisation with a venous or arterial long-line catheter allows:
- Injection of radio-opaque dye for angiography.
- Measurement of intracardiac pressures and oxygen saturations.
- Passage of electrophysiological instruments.
- Passage of angioplasty and valvuloplasty balloons.
The catheter is manipulated under fluoroscopic guidance. The patient is usually awake and on a cardiac monitor throughout. Most diagnostic studies are conducted as day cases.
Left heart catheterisation
This is performed via the arterial route:
- The femoral artery has been the most commonly used access point.
- The brachial artery may be used. This is usually done percutaneously rather than with surgical exposure of the artery.
- The radial artery is gaining favour as an access site and many studies report fewer local complications for a range of different interventions.[1, 2, 3, 4, 5] It is useful particularly when:
- There is significant femoral artery atherosclerosis.
- Obesity obscures anatomical landmarks.
Cardiac catheterisation allows for diagnostic confirmation and more detailed information after non-invasive studies. It can be used in assessment of the following:
- Left ventricular function.
- Severity of mitral and aortic valve disease.
- Outflow tract obstruction.
- The extent and severity of coronary artery disease (coronary angiography is the most common diagnostic study).
- Left ventricular biopsies may be taken (for example, in cardiomyopathies).
- Electrophysiological provocation studies can be performed (for example, for ventricular tachycardia).
The National Institute for Health and Care Excellence (NICE) recommends that angiography should be performed as soon as possible for patients who are clinically unstable or at high ischaemic risk.[6, 7]
Detailed analysis of the merits of such interventions is beyond the scope of this article. Such interventions include:
- Percutaneous transluminal coronary angioplasty (PTCA).
- PTCA and stenting.
- Treatment of acute coronary syndromes (ACS) by PTCA/stenting - a Cochrane review and others cautiously favour stents over PTCA, due to reduced risk of re-infarction and recurrent vessel occlusion.[8, 9]
- Treatment of acute myocardial infarction. There appear to be advantages to PTCA in terms of short-term outcome but there are some drawbacks as well. This has been facilitated by the development of acute percutaneous coronary intervention (PCI) centres.
- Balloon valvuloplasty.
- Septal infarction by alcohol injection for hypertrophic obstructive cardiomyopathy (HOCM).
Right heart catheterisation
This is performed by the venous route, via the femoral, internal jugular, subclavian or forearm veins.
Right heart catheterisation allows:
- Measurement of cardiac output, left ventricular filling pressure and pulmonary artery wedge pressure.
- Measurement of right heart oxygen saturations (for example, for septal defects).
- Assessment of pulmonary hypertension (for example, prior to cardiac transplantation).
- Electrophysiological provocation studies.
- Right-sided valvuloplasties.
- Radiofrequency ablation of, for example, the accessory pathway in Wolff-Parkinson-White syndrome.
- Direct thrombolysis into the pulmonary artery for massive pulmonary embolism.
- Insertion of electrodes for cardiac pacemaker devices.
In the critically ill patient, right heart catheterisation with a Swan-Ganz catheter may be used for acute monitoring of left and right ventricular function, to guide treatment and to monitor the effects of intervention. It has no direct therapeutic function. The catheter is usually inserted via the internal jugular or subclavian vein. Potential indications include:
- Shock (cardiogenic versus noncardiogenic).
- Respiratory distress (cardiogenic versus noncardiogenic).
- Complicated myocardial infarction.
- Monitoring effects of drugs (for example, cardiac inotropes).
- Assessing fluid requirements in patients with, for example, multi-organ failure.
Preparation for cardiac catheterisation
This will include:
- Investigations: day-case angiography does not usually require any routine pre-procedure investigations other than:
- Blood tests: FBC, U&E, clotting studies and group and save.
- Full explanation of the procedure with informed consent: it is not usually painful, although the injection of dye causes a warm flushing sensation.
- Premedication: anxious patients may require premedication with oral or intravenous (IV) diazepam.
- Other considerations: patients with renal impairment (creatinine >200 μmol/L) require 1 litre of normal saline IV over one hour before and after angiography to prevent X-ray contrast nephropathy. This may be problematic where there is associated heart failure.
Once consent has been given, there are no absolute contra-indications to cardiac catheterisation. The outcome of the procedure should have potential benefit greater than the risk associated with the procedure. However, a widespread risk-averse strategy to angiography may be preventing higher-risk patients from having revascularisation procedures.
- Relative contra-indications include:
- Severe hypertension.
- In shocked patients (for example, in acute gastrointestinal haemorrhage).
- Severe anaemia.
- Acute kidney injury.
- Severe congestive cardiac failure.
- Allergy to the contrast medium.
- Active infection or unexplained fever.
- Caution is required in higher-risk patients - for example, in:
- Extremes of age (under 1 year and over the age of 60 years).
- Severe coronary artery disease affecting the left main stem.
- New York Heart Association Classification class IV.
- Left ventricular ejection fraction <30%.
- Recent cerebrovascular disease.
- Chronic obstructive pulmonary disease.
Complication rates are low and include:
- Mortality for routine coronary angiography is approximately in the order of 0.8%.
- Haemorrhage from an arterial puncture site - apply pressure.
- False aneurysm (a firm, pulsatile swelling) - confirm with ultrasound.
- Dye reaction - skin reactions, nausea and vomiting, transient cortical disturbance; usually settle in <24 hours.
- Infection - early fever is usually a dye reaction.
- Loss of distal pulse(s).
- Angina and myocardial infarction.
- Pericardial tamponade.
- Infection (relatively low rate).
- Renal dysfunction.
Further reading and references
Kassam S, Cantor WJ, Patel D, et al; Radial versus femoral access for rescue percutaneous coronary intervention with adjuvant glycoprotein IIb/IIIa inhibitor use. Can J Cardiol. 2004 Dec20(14):1439-42.
Choussat R, Black A, Bossi I, et al; Vascular complications and clinical outcome after coronary angioplasty with platelet IIb/IIIa receptor blockade. Comparison of transradial vs transfemoral arterial access. Eur Heart J. 2000 Apr21(8):662-7.
Bertrand OF, De Larochelliere R, Rodes-Cabau J, et al; A randomized study comparing same-day home discharge and abciximab bolus only to overnight hospitalization and abciximab bolus and infusion after transradial coronary stent implantation. Circulation. 2006 Dec 12114(24):2636-43. Epub 2006 Dec 4.
Gilchrist IC, Moyer CD, Gascho JA; Transradial right and left heart catheterizations: a comparison to traditional femoral approach. Catheter Cardiovasc Interv. 2006 Apr67(4):585-8.
Ziakas A, Gomma A, McDonald J, et al; A comparison of the radial and the femoral approaches in primary or rescue percutaneous coronary intervention for acute myocardial infarction in the elderly. Acute Card Care. 20079(2):93-6.
Management of Acute Myocardial Infarction in patients presenting with ST-segment elevation; European Society of Cardiology (2012)
Unstable angina and NSTEMI; NICE Clinical Guideline (March 2010 - last updated November 2013)
West R, Ellis G, Brooks N; Complications of diagnostic cardiac catheterisation: results from a confidential inquiry into cardiac catheter complications. Heart. 2006 Jun92(6):810-4. Epub 2005 Nov 24.
Nordmann AJ, Hengstler P, Harr T, et al; Clinical outcomes of primary stenting versus balloon angioplasty in patients with myocardial infarction: a meta-analysis of randomized controlled trials. Am J Med. 2004 Feb 15116(4):253-62.
Fox KA, Anderson FA Jr, Dabbous OH, et al; Intervention in acute coronary syndromes: do patients undergo intervention on the basis of their risk characteristics? The Global Registry of Acute Coronary Events (GRACE). Heart. 2007 Feb93(2):177-82. Epub 2006 Jun 6.
Alexander KP, Newby LK, Cannon CP, et al; Acute coronary care in the elderly, part I: Non-ST-segment-elevation acute coronary syndromes: a scientific statement for healthcare professionals from the American Heart Association Council on Clinical Cardiology: in collaboration with the Society of Geriatric Cardiology. Circulation. 2007 May 15115(19):2549-69.
Ohlow MA, Secknus MA, von Korn H, et al; Incidence and outcome of femoral vascular complications among 18,165 patients undergoing cardiac catheterisation. Int J Cardiol. 2009 Jun 12135(1):66-71. Epub 2008 Jul 9.