Valvular Heart Diseases

Valvular Disease Overview - Valve Vibes Intro

• Valvular Heart Disease (VHD): Dysfunction of heart valves (mitral, aortic, tricuspid, pulmonary), impairing blood flow.
• Primary Lesions:
  • Stenosis: Valve narrowing → restricted flow → pressure overload.
  • Regurgitation (Insufficiency): Incomplete closure → backward flow → volume overload.
• Common Etiologies:
  • Rheumatic Heart Disease (RHD): Major cause, especially in India.
  • Degenerative: Calcification (aortic stenosis), myxomatous (MVP).
  • Infective Endocarditis.
  • Congenital (e.g., bicuspid aortic valve).
• Consequences: ↑ Cardiac workload → chamber hypertrophy/dilation → potential heart failure.

⭐ Rheumatic fever most commonly affects the mitral valve; mitral stenosis is the most frequent chronic rheumatic valvular lesion.

Mitral Valve Pathologies - Floppy & Tight

Mitral Stenosis (MS) - "Tight"

• Etiology: Rheumatic heart disease (RHD).
• Pathophys: ↓MVA → ↑LA pressure → Pulm. HTN.
• Clinical: Dyspnea, hemoptysis. Loud S1, Opening Snap (OS), mid-diastolic rumble (apex).
• Echo: MVA < 1.5 cm² (severe < 1.0 cm²); "Hockey-stick" leaflet.
• Rx: Medical (diuretics, β-blockers, OAC for AF). PTMC/MVR for severe/symptomatic.

Mitral Regurgitation (MR) - "Floppy"

• Etiology: MVP, RHD, ischemic, IE.
• Pathophys: LV volume overload → LV dilation/dysfunction.
• Clinical: Dyspnea, fatigue. Holosystolic murmur (apex → axilla).
• Echo: Regurgitant jet. Surgery if EF < 60% or LVESD > 40 mm.
• Rx: Medical (vasodilators). Surgery (repair > replacement) if symptomatic or LV dysfunction.

⭐ In MS, severity is primarily assessed by MVA; pressure gradient is flow-dependent and can be misleading.

Aortic Valve Pathologies - Narrow & Leaky

Aortic Stenosis (AS) - "Narrow"

• Etiology: Calcific (>70y), Bicuspid AV (<70y).
• Symptoms: 📌 SAD Triad: Syncope, Angina, Dyspnea.
• Murmur: Systolic ejection (crescendo-decrescendo), radiates to carotids. Soft S2.
• Severe AS (Echo): AVA <1.0 cm², Mean Gradient >40 mmHg, Jet Velocity >4 m/s.
• Treatment: Valve replacement (SAVR/TAVR) for symptomatic severe AS, LVEF <50%, or if very severe AS.

Aortic Regurgitation (AR) - "Leaky"

• Etiology: Acute (IE, dissection), Chronic (valve dz, root dilation e.g., Marfan).
• Symptoms: Dyspnea, palpitations. Wide pulse pressure.
• Murmur: Early diastolic decrescendo. Austin Flint murmur.
• Signs: Water-hammer pulse.
• Treatment: SAVR for symptomatic severe AR, or if LVEF ≤55% / LVESD >50mm.

⭐ In severe AR, surgery is indicated even in asymptomatic patients if LV End Systolic Dimension (LVESD) > 50 mm or LVEF ≤ 55%.

Other VHD & Prosthetics - Right Side & Fixes

• Tricuspid Regurgitation (TR): Functional (RV failure). Holosystolic murmur, LLSB, ↑ inspiration (Carvallo's sign 📌). RHF signs.
• Tricuspid Stenosis (TS): Rheumatic. Diastolic murmur, LLSB, opening snap.
• Pulmonary Stenosis (PS): Congenital. Systolic ejection murmur, ULSB, click.
• Pulmonary Regurgitation (PR): From pulm HTN (Graham Steell murmur).
• Prosthetic Valves (PHV):
  • Mechanical: Durable. Lifelong anticoagulation (INR: Mitral 2.5-3.5, Aortic 2.0-3.0).
  • Bioprosthetic: Less durable. Anticoagulation ~3 months.
  • Risks: Thrombosis, endocarditis, failure.
• IE Prophylaxis (High-Risk VHD): Dental, respiratory, infected tissue procedures.
  • Amoxicillin 2g PO.

  ⭐ Early Prosthetic Valve Endocarditis (<1 year post-op) often involves S. epidermidis; Late PVE resembles native valve IE.

High‑Yield Points - ⚡ Biggest Takeaways

• Rheumatic fever is the leading cause of mitral stenosis (MS).
• MS classically presents with a low-pitched, mid-diastolic murmur at the apex.
• Aortic stenosis triad: SAD (Syncope, Angina, Dyspnea on exertion).
• AS features a harsh crescendo-decrescendo systolic ejection murmur radiating to carotids.
• Severe aortic regurgitation can cause an Austin Flint murmur.
• AR signs include water hammer pulse and Corrigan's sign.
• Mitral valve prolapse is characterized by a mid-systolic click.