Hello and welcome to the Zero to Finals podcast.

My name is Tom and in this episode I'm going to be talking to you about prosthetic heart valves.

And you can find written notes on this topic at zero tofinals.com slash prosthetic heart valves

or in the cardiology section of the zero-definals medicine book.

So let's get straight into it.

Severe pathology of the aortic or mitral valves may be an indication for surgical replacement

of that valve.

The only other valve that may be replaced is the tricuspid

valve, although this is very rare. Aortic stenosis is the most common valvular heart disease

and the most common indication for valve replacement surgery. Mitral regurgitation is the

second most common indication for valve replacement.

Patients that have had a valve replacement will have a scar. Usually this is a midline

stenotomy scar straight down the middle of the sternum indicating a mitral or aortic valve

replacement or a coronary artery bypass graft.

Less commonly, a right-sided mini thoracotomy incision can be used for minimally invasive mitral valve surgery.

Let's talk about bioprostatic and mechanical valves. Valves can either be replaced by a

bioprosthetic or a metallic mechanical valve. Bioprothetic valves have a limited lifespan of around 10 years.

Horcine bioprothetic valves come from a pig.

Mechanical heart valves have a good lifespan well over 20 years,

but they require lifelong anticoagulation with warfarin.

In patients on warfarin for a mechanical valve, the INR target range is 2.5 to 3.5, which is notably

higher than the 2 to 3 target for atrial fibrillation.

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