Aortic valve replacement is a procedure involving replacement of damaged and improperly functioning aortic valves with artificial valves. Valve replacement approaches could be through:

  • Open heart surgery
  • Transcatheter aortic valve replacement (TAVR)
  • Minimally invasive cardiac surgery (MICS)

Valve replacement is the therapy of choice in symptomatic patients with severe aortic regurgitation [1]. It is specifically indicated in patients with:

  • An ejection fraction below 50% in AR patients
  • End-diastolic chamber diameter of >55mm in AR patients
  • Deteriorating function of LV in patients with AR
  • Significantly dilated LV but an asymptomatic AR phase
  • Reduced systolic pump function in patients with AR
  • Leaky aortic valves and presence of SOB as well as dilated LV affecting its function

Artificial valves are commonly of two different types, tissue and mechanical valves. Tissue valves are made of animal pericardial or heart valve tissue. Alternative to tissue valves include a homograft (a human aortic valve) donated by patients. Tissue valves are treated to prevent calcification and rejection. Disadvantages of these valves include:

  • Wear out faster
  • May require another surgery later for replacement
  • Increased flow demands

Mechanical valves known for being more durable than the former, require a single surgery and need not be replaced after few years unlike tissue valves. However, drawbacks of this type are:

  • Audible mechanic sound affecting life quality
  • Clotting
  • Life time anticoagulant intake
  • Increased risk of bleeding due to medications

Ross procedure better known as switch procedure is commonly performed on patients below 30, who are not in favor of the life time anti-coagulant intake. In this procedure aortic valves are replaced with pulmonary valves of the patient. In this type patient ends up having two valves at risk of failure.

Aortic valve replacement is more commonly performed through the open heart approach, which requires the patient to be placed on a cardiopulmonary bypass machine, which takes over the functions of heart and lungs. Once this is done, aorta is clamped and aortic valves replaced. Transesoaphageal echocardiogram assesses the function of newly placed valves.

Once completed the patient is kept in ICU for some time and is mostly discharged in 3-4 days in case of no complications, but recovery takes 5-6 months.

References

[1] Mandinov L1, Kaufmann P, Hess OM. Diagnosis and indication for aortic valve replacement in asymptomatic and symptomatic patients with aortic regurgitation. Herz. 1998 Nov;23(7):441-7.