Aortic valve replacement

Why are we operating?

Cutting out a stone-stiff valve and sewing in a new one, with the coronary openings watching from millimetres away.

Indication: Severe symptomatic aortic stenosis or regurgitation; the symptomatic stenotic valve is a countdown, not a diagnosis.

The operation in 4 steps

1. 01Bypass and aortotomy

   Sternotomy, onto bypass, cross-clamp, cardioplegia, then the aorta is opened just above the valve.

   Why: The valve can only be replaced from inside an opened, empty aorta; everything before the aortotomy exists to make that possible.

2. 02Excising the valve

   The calcified leaflets are cut out and the annulus debrided of calcium, with the field guarded against escaping debris.

   Why: Every fragment of calcium is a potential stroke; debridement must be complete enough to seat the prosthesis and gentle enough not to punch through the annulus into the structures behind it.

3. 03Sizing and implanting

   The annulus is sized, and the prosthesis seated and tied down on a ring of pledgeted sutures, orientated clear of the coronary ostia.

   Why: The prosthesis must seal without leaking around its sewing ring and must not shadow either coronary opening; both failures announce themselves when the heart restarts.

4. 04Closing and weaning

   Aortotomy closed, air vented meticulously, clamp off, wean from bypass under echo assessment of the new valve.

   Why: Air is the last enemy: a bubble sent up the right coronary or the brain undoes the operation. The echo is the exam the prosthesis must pass before the chest closes.

Danger zones

• Left main coronary artery

  Two territories hang from one vessel; its disease changes the whole operative plan.

• AV nodal artery

  Injury or occlusion at the crux trades a rhythm for an infarct.

• Coronary sinus

  Thin-walled and posterior, easily torn by retraction during mitral exposure.

Anatomy you need

The aortic valve with the conduction system kept on: the bundle of His passes millimetres from the annulus stitches.

What can go wrong

• Postoperative bleeding

  Tachycardia first, hypotension late; falling urine output; a distending abdomen or rising drain output.

• Surgical-site infection

  Wound erythema, warmth, discharge, and pain out of proportion, typically from postoperative day 4–7.

• Venous thromboembolism

  Unilateral leg swelling, or sudden dyspnoea, pleuritic pain, tachycardia, sometimes the only sign is unexplained hypoxia.