• Clinical science

Valvular heart diseases (Valvular heart defects)

Abstract

Valvular heart diseases can take the form of stenosis, insufficiency (regurgitation), or a combination of the two. These defects are typically acquired as the result of infections, underlying heart disease, or degenerative processes. However, certain congenital conditions can also cause valvular heart diseases. Acquired defects are found primarily in the left heart as a result of higher pressure and mechanical strain on the left ventricle. The type of valvular disease determines the type of cardiac stress and subsequent symptoms. Valvular stenosis leads to a greater pressure load and concentric hypertrophy, while insufficiencies are characterized by volume overload and an eccentric hypertrophy of the preceding heart cavities. Diagnostic procedures typically include ECGs, chest x-ray, and echocardiograms. Management consists of interventional or surgical procedures to reconstruct or replace valves, as well as medical treatment of possible heart failure.

Epidemiology

References:[1][2][3][4][5][6]

Epidemiological data refers to the US, unless otherwise specified.

Etiology

Valvular heart defects may either be acquired or congenital. Acquired defects are more common and typically occur secondary to infections (postinflammatory), degenerative processes, or heart disease.

Valve stenosis Valve regurgitation
Left heart Mitral valve
Aortic valve
  • Degenerative calcification (most common)
  • Rheumatic endocarditis
  • Congenital (e.g., unicuspid, bicuspid, or hypoplastic valve)
Right heart Tricuspid valve
Pulmonary valve
  • Congenital

References:[1][2][3][4][5][6][7][8]

Clinical features

All valvular defects can eventually lead to symptoms of heart failure as a result of excessive strain on the ventricles.

Physical examination

Auscultation in valvular defects
Maximum point Murmur Characteristics
Aortic stenosis
  • Aortic valve (parasternal 2nd right intercostal space)
  • Erb's point
  • Radiation into the carotids
  • Possibly ejection click
Aortic regurgitation
  • Diastolic murmur with a decrescendo
  • Possible additional quiet systolic murmur
  • Immediately following the 2nd heart sound (“immediate diastolic murmur”)
  • Austin-Flint-Murmur
Mitral stenosis
  • Heart apex (midclavicular 5th left ICS)
  • Delayed diastolic murmur with a decrescendo
  • Possible additional pre-systolic crescendo
  • “Tympanic” 1st heart sound
  • Mitral opening murmur/opening snap (OS)
Mitral valve prolapse
  • Heart apex (midclavicular 5th left ICS)
  • Late-systolic crescendo
  • Mid-systolic high-frequency click
Mitral regurgitation
  • Heart apex (midclavicular 5th left ICS)
  • Left axilla
  • Blowing
  • Radiation into the axilla

Pulmonary stenosis

  • Crescendo-decrescendo ejection systolic murmur
  • Possible radiation into the back

  • Possible early systolic pulmonary ejection click and/or widely split 2nd heart sound

Pulmonary regurgitation
  • Diastolic murmur with a decrescendo
  • Graham Steel murmur: high-frequency decrescendo diastolic murmur
Tricuspid stenosis (extremely rare)
  • Delayed diastolic murmur with a decrescendo
  • Possible pre-systolic crescendo
Tricuspid regurgitation (extremely rare)

References:[9][10][11][7][8]

Treatment

Symptomatic

Causal

  • Surgery: The choice of procedure is based on the patient's individual risk profile and an evaluation of benefits.
    • Valve reconstruction (annuloplasty)
      • Procedure: ring-shaped device attached to the outside of the valve opening to re-establish shape and function of valve
      • Reduced thromboembolic risk compared to mechanical valve replacement; but high risk of recurring stenosis
      • Lower mortality rate than valve replacements, though replacements are more durable
    • Prosthetic valve replacement
Prosthetic heart valve
Mechanical prosthetic valve Biological prosthetic valve
Pros
  • Valve has a long lifespan
  • Anticoagulation only necessary for 3 months post operation
Cons
  • Short lifespan due to sclerotic degeneration
    • May need to be replaced every ten years
Indications
  • Younger patients
  • Previously anticoagulated patients (e.g., with pre-existing atrial fibrillation)
  • Older patients
  • Patients with a high risk of bleeding
  • Women with a desire to have children
  • Interventional procedures via catheter
    • Valve replacement, e.g., transcatheter aortic valve replacement (TAVR); or transcatheter mitral valve replacement (TMVR)

Percutaneous balloon valvuloplasty for stenoses

References:[12][13]