Synonyms: percutaneous transluminal coronary angioplasty (PTCA), formerly known as balloon angioplasty.

This is one of the two coronary revascularisation techniques currently used in the treatment of ischaemic heart disease¹, the other being coronary artery bypass grafting (CABG).

Percutaneous coronary intervention (PCI) involves non-surgical widening of the coronary artery, using a balloon catheter to dilate the artery from within. A metallic stent is usually placed in the artery after dilatation. Antiplatelet agents are also used. Stents may be either bare metal or drug-eluting stents (see box).

Indications for percutaneous coronary intervention

Note that indications for PCI may change as the procedures continue to be refined, and with emerging evidence.

1. ST segment elevation myocardial infarction (STEMI):²
   • When available, angioplasty with stenting is the optimal method of reperfusion for STEMI. The target "door to balloon time" is 90 minutes.
   • As rescue treatment in patients treated by thrombolysis - if there is failure to reperfuse, further ischaemia or further MI.
   • As early intervention in patients treated with thrombolysis.
2. Non-ST elevation acute coronary syndrome (NSTACS) - unstable angina and non-ST elevation myocardial infarction (NSTEMI):²
   • For patients who are at medium-to-high risk of subsequent cardiac events, offer angiogram and/or PCI before discharge. Early invasive investigation and revascularisation (compared to conservative treatment) may reduce subsequent MI and refractory angina.
3. Stable angina:¹
   • Patients with single or double vessel disease, where optimal medical therapy fails to control symptoms.
   • Patients with triple vessel disease, who are unsuitable for CABG.

Contra-indications and other considerations

• Consider the pros and cons of PCI versus optimal drug therapy and/or CABG.^3,4
• Because anti-platelet drugs are crucially important after PCI (to prevent thrombosis in the stent, see below), decisions about PCI and the type of stent used must bear in mind:^5,6
  • Is there likelihood that surgery will be needed? Consider the increased risk of bleeding with antiplatelet drugs, but risk of thrombosis if these drugs are stopped.
  • Can the patient adhere to antiplatelet treatment (and is there funding to do so)?
  • Any contra-indications to antiplatelet drugs.

The procedure⁷

• PCI should be done by experienced, high volume operators and institutions.
• No anaesthetic is needed, though patients may be given a sedative. Patients can usually mobilise a few hours afterwards, and go home the same or next day.
• The technique involves gaining arterial access via the femoral, radial or brachial arteries. Under fluoroscopy, a guidewire is passed into the coronary artery and across the stenosis; the balloon or stent catheter passed over it, and the lesion dilated and/or stented. Glycoprotein IIb/IIIa inhibitors are given in 'high-risk' procedures, and opiates may be used if angina occurs during angioplasty.

Post-procedure

Antiplatelet drug treatment following percutaneous coronary intervention^6,9

• All patients should take aspirin indefinitely (as secondary prevention of CVD).
• 'Dual antiplatelet therapy' is required for patients with coronary stents to reduce the risk of stent thrombosis:
  • This normally comprises aspirin and clopidogrel. The duration of clopidogrel treatment depends on the clinical setting, but current recommendations are usually:
    • For BMSs, clopidogrel for at least one month.
    • For DESs, clopidogrel for at least 12 months. Some cardiologists feel that clopidogrel should be continued indefinitely.
• Antiplatelet agents should not be stopped, and patients are advised to carry a warning card. Cards are available from the UK Clinical Pharmacy Association (admin@ukcpa.com).¹⁰
• If surgery is required, consider whether the antiplatelet drugs can be continued; consult with cardiologist as to the risks of discontinuing these drugs and any necessary precautions.⁹
• The use of proton-pump inhibitors together with clopidogrel (to prevent gastric bleeding) is controversial, after evidence suggesting that PPIs may worsen outcomes, and that the two drugs may interact.

Driving¹¹

After elective PCI:

• Group 1 licence - stop driving for 1 week; can recommence thereafter if there is no other disqualifying condition. DVLA need not be notified.
• Group 2 license - stop driving for at least 6 weeks. Re-licensing may be permitted thereafter provided that other functional test requirements can be met and there is no other disqualifying condition.

Complications^6,7

• Stent thrombosis:
  • This is a risk until the stent becomes covered by endothelium.
  • Usually presents as acute MI, with a high mortality.
  • Is most frequent during the first month, but can occur months or years after the PCI.
  • Occurs in 1-2% of patients.
• Restenosis of the stent:
  • This is due to excessive 'healing' of the vessel wall, which encroaches on the stent lumen.
  • Typically, it develops within 3-6 months.
  • Presents as a return of angina; rarely causes MI.
  • Occurs in 4-20% of stents.
• Other major complications are uncommon, but include: death (0.2% but higher in high-risk cases), acute MI (1%) which may require emergency CABG, stroke (0.5%), cardiac tamponade (0.5%) and systemic bleeding (0.5%).
• Minor complications are: allergy to the contrast medium, nephropathy and complications at the access site, such as bleeding and haematoma.

Possible future developments

• Bioabsorbable stents are being trialled and have potential advantages.¹²
• Triple antiplatelet therapy may be beneficial.¹³
• New anti-thrombotic drugs, such as thrombin receptor (protease activated receptor-1 (PAR-1)) antagonists might reduce thrombosis without affecting haemostasis.¹⁴

Document references

1. Management of stable angina, SIGN (2007)
2. Acute coronary syndrome, Map of Medicine (Cardiology)
3. Taggart DP; Coronary revascularisation. BMJ. 2007 Mar 24;334(7594):593-4.
4. Mukherjee D, Moliterno DJ; Effectiveness of PCI for non-acute coronary artery disease. Lancet. 2009 Mar 14;373(9667):870-2.
5. Bavry AA, Bhatt DL; Appropriate use of drug-eluting stents: balancing the reduction in restenosis with the concern of late thrombosis. Lancet. 2008 Jun 21;371(9630):2134-43. [abstract]
6. BHF factfile: managing patients with coronary stents. British Heart Foundation, Oct 2008.
7. Grech ED; ABC of interventional cardiology: percutaneous coronary intervention. II: the procedure. BMJ. 2003 May 24;326(7399):1137-40.
8. Coronary artery disease - drug-eluting stents, NICE Technology Appraisal Guidance (July 2008)
9. Cruden NL, Harding SA, Newby DE; Coronary stent thrombosis in the perioperative period. BMJ. 2008 Nov 24;337:a2074. doi: 10.1136/bmj.a2074.
10. Antoniou S, Rothman MT; Stent thrombosis: patient card on discontinuing clopidogrel is available. BMJ. 2007 Jan 13;334(7584):57.
11. At a Glance Guide to the Current Medical Standards of Fitness to Drive, Driver and Vehicle Licensing Agency, Swansea
12. Colombo A, Sharp AS; The bioabsorbable stent as a virtual prosthesis. Lancet. 2009 Mar 14;373(9667):869-70.
13. Chen KY, Rha SW, Li YJ, et al; Triple versus dual antiplatelet therapy in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention. Circulation. 2009 Jun 30;119(25):3207-14. Epub 2009 Jun 15. [abstract]
14. Colombo A, Merlini P; The ischaemia/bleeding balance in PCI. Lancet. 2009 Mar 14;373(9667):872-3.

Internet and further reading

• Agostoni P, Van den Branden F; Drug eluting stents in patients with diabetes. BMJ. 2008 Aug 29;337:a1359. doi: 10.1136/bmj.a1359.
• Bates ER, Nallamothu BK; Commentary: the role of percutaneous coronary intervention in ST-segment-elevation myocardial infarction. Circulation. 2008 Jul 29;118(5):567-73.
• Bravata DM, Gienger AL, McDonald KM, et al; Systematic review: the comparative effectiveness of percutaneous coronary interventions and coronary artery bypass graft surgery. Ann Intern Med. 2007 Nov 20;147(10):703-16. Epub 2007 Oct 15. [abstract]
• Trikalinos TA, Alsheikh-Ali AA, Tatsioni A, et al; Percutaneous coronary interventions for non-acute coronary artery disease: a quantitative 20-year synopsis and a network meta-analysis. Lancet. 2009 Mar 14;373(9667):911-8. [abstract]
• Kirtane AJ, Gupta A, Iyengar S, et al; Safety and efficacy of drug-eluting and bare metal stents: comprehensive meta-analysis of randomized trials and observational studies. Circulation. 2009 Jun 30;119(25):3198-206. Epub 2009 Jun 15. [abstract]

Acknowledgements