Mitral Valve Repair/Replacement

Airway: ETT
Access: 14G IVC or MAC line, arterial line, CVC, +/- PAC
Pain: Substantial, especially in younger patients
Position: Supine/crucifix
Time: 3-4 hours
Blood loss: ~400ml. G+H required, consider cross-match of at least 2 units.
Special: CPB - higher risk for anaesthetic awareness. Risk of air embolism as left heart is opened.

Mitral valvular surgery is performed for:

The valve can be either:

Considerations

This covers factors unique to MVR. Factors relating to cardiac surgery in general are covered here.

  • A
    • OLV required for minimally invasive approach Need either DLT or bronchial blocker.
  • B
    • Pulmonary oedema
      May have secondary effusions.
  • C
    • Atrial fibrillation
      • Often coexistent due to atrial dilation
        May be anticoagulated.
      • AF may result in precipitous decline in both MS and MR
    • Severity of valvular disease
    • Consequences of valvular disease
      • PHTN
      • Cardiac remodelling
    • Presence of coronary disease
    • Pulmonary artery hypertension
      May be associated with both MR and MS.
    • Defend perfusion pressure
      • MS leads to a relatively fixed CO and elevated SVR; therefore CBF will fall and not be compensated with a fall in perfusion pressure
    • Avoid elevation in PVR

Induction

Intraoperative

Surgical Stages

For standard approach:

  • Sternotomy
  • Establish CPB
  • Empty left heart via the PA
  • Establish diastolic arrest
  • Open the LA
  • Decision made for repair or replacement, and this is performed
  • LV and atrium are filled
  • Atrium is closed
  • Ventricle is de-aired
  • Cross-clamp is removed and coronary perfusion commences
  • Wean from CPB occurs once air is removed from circulation

Minimally invasive approach:

  • Patient positioned in left lateral (right side up)
  • CPB established typically by peripheral (femoral-femoral) cannulation
  • Deflation of the right lung required to facilitate surgical access
  • Diastolic arrest and cross-clamping

Postoperative

  • May require vasodilator due to residual pulmonary hypertension