Coronary Artery Disease and Percutaneous Coronary Intervention
Core concepts
Know the PCI decision framework: indication (stable angina vs. ACS), lesion complexity (ACC/AHA type A–C), and completeness of revascularization. Understand stent platforms (durable-polymer DES, biodegradable-polymer DES, polymer-free, BMS), the mechanism of restenosis (neointimal hyperplasia for BMS; neoatherosclerosis and polymer hypersensitivity for DES), and stent thrombosis timing (acute <24 h, subacute 24 h–30 d, late 30 d–1 y, very late >1 y). Master DAPT duration logic: default 6–12 months after elective DES, with shortening for high bleeding risk and prolongation for high ischemic/thrombotic risk. Know physiology-guided PCI (FFR ≤0.80, iFR ≤0.89) and intracoronary imaging (IVUS/OCT) for optimization.
Traps
- Equating angiographic severity with ischemia; moderate lesions need physiology.
- Forgetting that left main PCI requires IVUS and often physiology of the non-culprit vessel.
- Confusing in-stent restenosis management (drug-coated balloon vs. repeat DES) with de novo disease.
- Missing that bifurcation two-stent techniques (culotte, crush) carry higher stent thrombosis risk.
- Overlooking that chronic total occlusion PCI is elective and physiology/viability should guide it.
Rule of thumb
For stable CAD, treat ischemia-producing lesions (FFR/iFR positive) and leave non-ischemic lesions alone-except for left main disease, where angiography plus IVUS often drives revascularization regardless of physiology. Default DAPT after elective DES is 6 months; extend only for a clear ischemic rationale.
Worked example
A 62-year-old with stable angina has a 60% mid-LAD lesion. FFR = 0.76. PCI is indicated because FFR ≤0.80 confirms ischemia. If FFR were 0.85, defer PCI and treat medically.