Valvular Heart Disease (Murmur Approach, Severity & Timing of Intervention)
Source: PMK Board Review #29 — Endocardial Disease (Valvular Heart Disease; IE deferred) lecture + 2020/2025 ACC/AHA & ESC VHD guidelines (current as of 29 มิ.ย. 2026)
🎯 Board-exam takeaway: Symptom แยก pathology ไม่ได้ — ต้องใช้ sign (PE). Murmur approach: systolic/diastolic/continuous → timing & location. AS triad = Syncope, Angina, DOE (SAD). Acute valve disease = emergency/surgical (flash pulmonary edema + heart ไม่โต + อาจไม่ได้ยิน murmur). Mechanical valve → VKA only (ไม่มี NOAC).
🔗 Fellowship-depth companion pages (ลงลึกกว่า board-review นี้): AS (Aortic Stenosis) · AR (Aortic Regurgitation) · MS (Mitral Stenosis) · MR (Mitral Regurgitation) · TR (Tricuspid Regurgitation) · Pulmonary Valve Disease · IE (Infective Endocarditis) · Prosthetic Heart Valves · TAVR (Transcatheter Aortic Valve Replacement) · Transcatheter Mitral & Tricuspid Therapies · Acute Rheumatic Fever & RHD
🧬 Etiology & Epidemiology
Epidemiology เปลี่ยน: อายุยืนขึ้น → degenerative/functional มากขึ้น, rheumatic ลดลง.
| Valve | สาเหตุ |
|---|---|
| MS | Rheumatic (เด่น), degenerative, radiation, inflammatory disease |
| MR | Primary (ลิ้นป่วยก่อน: prolapse, rheumatic, IE, degenerative) vs Secondary/functional (LV ป่วย→dilate→MR) |
| AS | 3 สาเหตุ: degenerative (อายุ >70), congenital bicuspid (เร็วกว่า ~10 ปี), rheumatic (+ MS) |
| AR | Primary (leaflet: AS causes + IE = 4 สาเหตุ) vs Functional (aortic root dilation: dissection, connective tissue, vasculitis, annuloaortic ectasia/aneurysm) |
🩺 Clinical Phenotypes (Symptom Groups)
อาการ VHD เกิดจาก 4 กลไก: (1) low output (DOE, fatigue, exercise intolerance — DOE ≠ heart failure); (2) heart failure (PND, congestion); (3) complication (systemic embolization, palpitation, arrhythmia); (4) associated disease (Marfan → lens subluxation).
- AS classic triad = Syncope, Angina, DOE (SAD); ± sudden death, GI bleed (angiodysplasia/Heyde)
- MS: เหนื่อย, hemoptysis (จาก bronchial vein dilation), systemic embolization (15–50%), right-sided failure, Ortner syndrome (LA โตกด recurrent laryngeal n. → hoarseness, พบน้อย)
- AR/MR: usually asymptomatic, incidental; DOE = most common presenting symptom เมื่อ severe
Symptom แยก pathology ไม่ได้ — ทุกโรคมาอาการคล้ายกัน. Sign (PE) ต่างหากแยกได้.
🩻 Physical Exam & Murmur Approach
Innocent murmur (7S): Soft, Systolic, Short, asymptomatic (no Symptom), normal S1/S2 (no extra Sound), no Special test abnormality, ↓เมื่อ Standing/Sitting. ต.ย.: pregnancy mammary soufflé.
Pathologic murmur — แยก 3 กลุ่ม:
- Continuous (machinery, ไม่หยุดตรงกลาง — ต่างจาก to-and-fro): PDA, AV fistula, ruptured sinus of Valsalva
- Pansystolic: MR (apex), TR (LLSB), VSD (± thrill)
- Late systolic: MVP
- Ejection systolic: AS (along aortic area, radiates to carotid)
Pulse แยกก่อน: Hypokinetic pulse + non-displaced PMI → obstructive (AS/MS); hyperkinetic + lateral displaced PMI → regurgitant (MR/AR).
Murmur ต่อโรค:
- AS: systolic ejection murmur, aortic area, radiate to carotid
- MS: diastolic rumbling murmur at apex + opening snap (low-pitch หลัง S2)
- MR: MVP → late systolic; อื่น → pansystolic
- AR: to-and-fro (systolic + diastolic) at Erb point — แยก PR ด้วย sign: AR = peripheral CV-AR signs; PR = pulmonary hypertension
Dynamic auscultation (ออกสอบ choice):
- AS vs HOCM: squatting/standing (↑preload → AS ดังขึ้น, HOCM เบาลง)
- MVP: standing (↓LV) → click + murmur earlier; ↑LV → click + murmur later (click late, murmur late)
- TR vs MR: inspiratory increase = Carvallo sign → TR
💊 Severity Signs, Acute vs Chronic & Management
Severity (CV = clinically severe) signs:
- AS: pulsus parvus et tardus, absent/single S2 (loss of normal split), murmur grade ≥4 with thrill; normal splitting = NOT severe (negative sign); CXR aortic valve calcification = almost always severe
- MR: S3 gallop, signs of pulmonary hypertension. Silent MR เจอได้ใน acute MR, post-MI, paraprosthetic leak, obese/emphysema
- AR: peripheral signs of CV-AR (หาแค่ 2 sign ก็พอ)
- MS: holodiastolic, diastolic thrill, short OS-P2 interval, diastolic accentuation, absent S1
Acute vs Chronic (สำคัญ): Acute = emergency, surgical — severe, sudden, severe pulmonary edema, heart ไม่โต, อาจไม่ได้ยิน murmur. Acute MR = papillary muscle/chordal rupture (post-MI), IE; acute AR = IE, aortic dissection. MR → IABP ได้; AR → IABP ไม่ได้. Acute valve obstruction (large IE vegetation/thrombus) → cardiogenic shock, surgical.
Severity → echocardiogram (ไม่ต้องจำ parameter — เปิดตารางได้).
Medical therapy — VHD ส่วนใหญ่ = intervention disease. Medication มีบทบาท: บรรเทาอาการ, treat related condition, rheumatic prevention, IE prophylaxis, thromboembolic prevention. ยกเว้น: secondary/functional MR → GDMT (LV dysfunction) → MR downgrade ได้.
Antithrombotic (จำ):
- VKA only: mechanical valve, surgical bioprosthetic ≤3 เดือนแรก, rheumatic MS moderate-severe
- MV/TV repair, bioprosthetic >3 เดือน → NOAC หรือ aspirin
- 2025 guideline: mechanical valve + high thrombotic risk → major non-cardiac surgery → หยุด VKA + bridging, หยุด ≥4 วัน (INR <1.5), resume ภายใน 24 h เมื่อ safe
📚 Timing of Intervention (สำคัญที่สุด)
AS: (1) symptomatic severe → ผ่าทุกราย; (2) asymptomatic + EF <50% (class 1) / <55% (2A); (3) high-risk hemodynamic deterioration (very severe Vmax >5 m/s, progression >0.3 m/s/yr, ↑↑biomarker); (4) EST drop SBP >20 mmHg → surgery. Intervention = SAVR vs TAVR (อายุ >70).
AR: symptomatic severe → surgery; asymptomatic EF <50% or LV end-systolic dimension >50 mm (or 25 mm/m²) → surgery (class 1). Root indication: >55 mm; >50 mm bicuspid/coarctation; >45 mm Marfan + genetic abnormality.
MR (primary): symptomatic → surgery; asymptomatic EF <60% or LVESD >40 mm → repair. Secondary MR → GDMT ก่อน, ไม่ downgrade → intervention.
MS: cutoff valve area 1.5 cm² + symptom → PTMC (ถ้าทำได้); ถ้าทำไม่ได้ + surgical risk ต่ำ → surgery.
Anticoagulation in pregnancy: 1st trimester — VKA dose >5 mg/day → เปลี่ยน LMWH (monitor anti-Xa); ≤5 mg/day → continue VKA ได้.
IE prophylaxis (ไว้ต่อ): high-risk pathology (previous IE, prosthetic valve/material, untreated/residual cyanotic CHD) + dental procedure = class 1; GI/GU/skin invasive = 2A.