PCI Versus CABG in Coronary Artery Disease
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Direct answer
PCI and CABG are the two revascularisation options for coronary artery disease: PCI opens the narrowing with a catheter-delivered stent, while CABG bypasses it with an arterial or venous graft. CABG is generally favoured for left main or complex multivessel disease, particularly in diabetics, and the SYNTAX score grades anatomical complexity to guide the choice. Simple one- or two-vessel disease is usually treated with PCI, which avoids sternotomy.
What you must remember
- SYNTAX score: an angiographic complexity score graded low at 22 or less, intermediate from 23 to 32, and high at 33 or more.
- Left main disease: significant left main stenosis is generally treated with CABG, with PCI reserved for selected low-complexity anatomy.
- Diabetes with multivessel disease: CABG offers better long-term survival and fewer repeat revascularisations than PCI.
- LIMA graft: the left internal mammary artery grafted to the left anterior descending artery is the most durable conduit.
- Stent types: drug-eluting stents have largely replaced bare-metal stents because they reduce restenosis.
- Antiplatelet therapy: dual antiplatelet therapy is needed after stenting, typically for six to twelve months, and interrupting it risks stent thrombosis.
- Heart Team: cardiologists and cardiac surgeons decide together, weighing anatomy, diabetes, ejection fraction and patient preference.
Choosing a strategy for a complex patient
A 64-year-old diabetic man with angina, three-vessel disease, an ejection fraction of 40 per cent and a SYNTAX score of 28 is referred for revascularisation. The table compares the two strategies on the factors that usually decide the choice.
| Factor | PCI | CABG |
|---|---|---|
| Access and procedure | Catheter through radial or femoral artery | Sternotomy with cardiopulmonary bypass |
| Recovery | Usually days | Usually several weeks |
| Long-term repeat procedures | Higher, especially in diabetes | Lower over the long term |
| Best suited to | Simple one- or two-vessel disease | Left main or diabetic multivessel disease |
For this patient the Heart Team would usually favour CABG, because diabetes with multivessel disease gives better long-term outcomes with surgery. The choice would change if the anatomy were simpler or the patient declined surgery.
Complete revascularisation, meaning treatment of all significant lesions, is a goal in both strategies, and incomplete treatment is a common reason for later events. Graft choice also matters, since an internal mammary graft to the LAD usually outlasts a venous graft.
Where the exam tries to catch you
Revascularisation questions turn on anatomy and diabetes rather than on the procedure itself, so the traps below focus on those points.
- Trap: PCI is chosen for left main stenosis because it is less invasive. Correct: CABG is generally preferred for significant left main disease, with PCI reserved for selected low-complexity anatomy.
- Trap: diabetics with multivessel disease are given PCI by default. Correct: CABG gives better long-term survival and fewer repeat procedures in diabetes with multivessel disease.
- Trap: a saphenous vein graft is expected to last as long as an internal mammary graft. Correct: the LIMA to LAD graft is the most durable, while saphenous vein grafts fail more often over time.
Frequently asked questions
What is the SYNTAX score used for?
The SYNTAX score grades the angiographic complexity of coronary artery disease and helps decide between PCI and CABG. Low scores of 22 or less generally favour PCI, while scores of 33 or more favour CABG for multivessel disease.
When is CABG preferred over PCI in left main disease?
CABG is generally preferred for significant left main coronary stenosis, especially when the SYNTAX score is high or the patient has diabetes. PCI is reserved for selected patients with low-complexity left main anatomy.
Why is CABG favoured in diabetics with multivessel disease?
CABG gives better long-term survival and fewer repeat revascularisations than PCI in diabetics with multivessel disease. Stents in these patients restenose more often, which is why surgery is the usual recommendation for complex anatomy.
Which graft lasts longest after CABG?
The left internal mammary artery grafted to the left anterior descending artery is the most durable conduit after CABG. Saphenous vein grafts fail more often over time, which is why the internal mammary graft is preferred for the LAD.
How long must dual antiplatelet therapy continue after drug-eluting stent placement?
Dual antiplatelet therapy is generally continued for about six to twelve months after drug-eluting stent placement, the period in which stent thrombosis risk is highest. The exact duration is individualised according to bleeding risk and the clinical presentation.