285.2 🩺 國考版

285.2.1 高頻考點

285.2.1.1 AS Severity (Echo)

  • Peak vel ≥ 4 m/s
  • Mean gradient ≥ 40 mmHg
  • AVA ≀ 1.0 cm² (or ≀ 0.6 indexed)

285.2.1.2 AS Stages (ACC/AHA 2020)

  • A (at risk) → B (progressive) → C (asymptomatic severe; C1 normal LV, C2 LV dysfunction) → D (symptomatic severe; D1 high-grad, D2 low-flow low-grad reduced EF, D3 paradoxical low-flow preserved EF)

285.2.1.3 Dobutamine Stress Echo (for low-flow, low-grad)

  • True severe AS: increasing gradient with stable area
  • Pseudosevere AS: increase in area with flow recovery
  • No contractile reserve: poor prognosis

285.2.1.4 AS Surgical/TAVR Indications

  • Symptomatic severe AS (any flow pattern)
  • Asymptomatic severe + LV dysfunction (EF < 50%)
  • Asymptomatic severe + abnormal stress test
  • Asymptomatic + very severe (peak vel ≥ 5)
  • Asymptomatic + cardiac surgery for other reasons
  • EARLY-TAVR 2024: select asymptomatic severe → early TAVR

285.2.1.5 AS Key Trials

  • PARTNER 1A/B (inoperable, high-risk): TAVR established
  • PARTNER 2/3, SURTAVI: intermediate / low risk
  • EARLY-TAVR 2024: asymptomatic severe AS

285.2.1.6 AR Surgical Indications

  • Symptoms (NYHA II-IV)
  • LV EF < 55% (Class I)
  • LVESD > 50 mm or indexed > 25 mm/m² (Class I)
  • LVEDD > 65 mm (Class IIa some)
  • Aortic root > 5.0-5.5 cm

285.2.1.7 AR Examination

  • Wide pulse pressure
  • Diastolic decrescendo murmur at LSB sitting forward, expiration
  • Bounding pulses; eponyms (de Musset, MÃŒller, Quincke, Traube, Duroziez, Hill, Becker)
  • Austin Flint = severe AR diastolic apical rumble

285.2.1.8 Acute AR

  • Acute pulmonary edema, shock
  • Causes: dissection, endocarditis, trauma
  • EMERGENCY surgery
  • Avoid β-blocker (tachycardia is compensatory)

285.2.2 易混淆比范

Feature AS AR (chronic) AR (acute)
Murmur Systolic crescendo-decrescendo R 2nd ICS Diastolic decrescendo LSB sitting forward Often soft / no murmur
Pulse Parvus et tardus Bounding, wide PP Narrow, weak
LV Concentric LVH Eccentric, dilated Normal-sized, ↑ EDP
Symptoms SAD; sudden post-symptom Slow progression Acute decompensation
Treatment TAVR/SAVR if symptomatic, severe AVR if symptoms or LV dysfunction Emergency surgery

285.2.2.1 TAVR Complications

  • Vascular access (10-15%)
  • Stroke (3-5%)
  • Paravalvular leak (improved with new gen)
  • Conduction abnormalities (LBBB, AV block) → permanent pacer 5-15%
  • Acute kidney injury
  • Bleeding
  • Coronary obstruction (rare; preprocedural CT critical)