272.3 🏥 內科專科考前版

272.3.1 Mechanistic Deep Dive

272.3.1.1 Plaque Biology

  • Lipid-rich necrotic core, thin fibrous cap (< 65 ÎŒm = vulnerable)
  • Macrophage MMP secretion → cap thinning
  • Inflammation drives rupture
  • CANTOS trial 2017 — canakinumab (anti-IL-1β) ↓ MACE
  • LoDoCo2 2020 — colchicine 0.5 mg daily ↓ MACE in CCS
  • 2024 AHA/ACC: low-dose colchicine considered for high-risk patients

272.3.1.2 Microvascular Dysfunction

  • Impaired endothelium-dependent vasodilation (NO pathway)
  • Smooth muscle hyper-reactivity
  • Inflammation + oxidative stress
  • Treat: statin, ACEi, smoking cessation, exercise

272.3.1.3 Novel Imaging

  • OCT (optical coherence tomography) — intracoronary, 10x resolution of IVUS, identifies thin-cap fibroatheroma
  • NIRS-IVUS — lipid core burden index (LCBI), predicts MACE
  • Coronary FDG-PET — plaque inflammation
  • Coronary CT FFR — non-invasive FFR

272.3.2 Recent Trials & Updates

272.3.2.1 ORBITA-2 (2023)

  • 301 patients, single-vessel stable angina, on placebo run-in (no anti-anginal)
  • PCI vs sham PCI
  • Primary endpoint: angina symptom score (Cantonberry questionnaire)
  • Result: PCI significantly better symptom score (2.21 vs 5.18, p < 0.001)
  • Resolves prior ORBITA controversy when patients were heavily medicated

272.3.2.2 ISCHEMIA-EXTEND (2023)

  • 7-year follow-up of ISCHEMIA
  • Cardiovascular mortality lower with invasive (in some subgroups)
  • All-cause mortality unchanged
  • Confirms anti-anginal benefit but mortality benefit uncertain

272.3.2.3 REVIVED-BCIS2 (2022)

  • PCI vs OMT for ischemic cardiomyopathy (EF ≀ 35%)
  • No benefit of PCI on death/HF hospitalization
  • Challenges old paradigm of revascularization in HFrEF

272.3.2.4 LoDoCo2 (2020) + COLCOT (2019)

  • Low-dose colchicine (0.5 mg/d) reduces MACE in CCS + post-MI
  • AHA/ACC 2023 Class IIa for high-risk CCS

272.3.2.5 Lipoprotein(a)

  • Genetic, independent CAD risk factor
  • Test once in lifetime per 2024 NLA/ESC guidance
  • Pelacarsen (siRNA), muvalaplin in trials
  • High Lp(a) ≥ 50 mg/dL or ≥ 125 nmol/L → intensify other risk factors

272.3.2.6 COMPASS (2017)

  • Rivaroxaban 2.5 mg BID + ASA 100 mg vs ASA alone in stable CAD/PAD
  • ↓ MACE 24%, ↑ bleeding 70%
  • Net clinical benefit favorable
  • AHA/ACC 2023 Class IIa for high-risk CCS

272.3.3 High-Yield Specialist Points

272.3.3.1 Special Populations

  • DM: BP < 130/80, HbA1c individualized (typically < 7%), SGLT2i + GLP-1 RA
  • CKD: ACEi/ARB; avoid contrast if possible; consider periprocedural hydration
  • Elderly: lower revascularization threshold, focus on QOL
  • Women: microvascular more common, INOCA workup

272.3.3.2 Spontaneous Coronary Artery Dissection (SCAD)

  • Young/middle-age women
  • Fibromuscular dysplasia association
  • Pregnancy / postpartum
  • Conservative management preferred (not PCI unless STEMI or hemodynamic instability)
  • Avoid stress testing or anticoagulants

272.3.3.3 Coronary Spasm

  • Acetylcholine challenge in cath lab is gold standard
  • Often co-exists with microvascular angina (mixed phenotypes)
  • ROCK inhibitors investigational

272.3.3.4 MINOCA (MI with Non-obstructive Coronary Arteries)

  • ~ 5-10% of MI
  • Causes: SCAD, vasospasm, embolism, supply-demand mismatch, myocarditis, takotsubo
  • CMR is key for differential diagnosis
  • Tailor treatment to cause

272.3.4 Pearls

  • Stable CCS now formal name — replaces “stable IHD” (2019 ESC, 2024 update)
  • CCTA-first strategy is now mainstream (2024 NICE/ESC)
  • ISCHEMIA + ORBITA-2 define modern role of PCI: symptom-driven, not prognosis-driven
  • Lp(a) test once in lifetime — emerging therapies coming
  • LoDoCo2 / COMPASS / SGLT2i / GLP-1 — newer secondary prevention building blocks