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 Cardiothoracic surgery section of the zero

de finals surgery 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. Replacement of the tricuspid

valve is very rare. So mainly if there's a valve

replacement, it will either be the aortic valve or the mitral valve. Patients that have a valve

replacement will have a scar. Usually this will be a midline stenotomy scar straight down the

middle of the sternum, indicating a mitral or an aortic valve replacement.

A midline's denotomy scar can also indicate a coronary artery bypass graft or cabbage.

Less commonly, patients may have a right-sided mini thoracotomy incision, which can be used for

minimally invasive mitral valve surgery.

Let's start by talking about aortic stenosis.

Severe aortic stenosis is the most common valvular heart disease that you'll encounter,

and also the most common indication for valve replacement surgery.

Aortic stenosis causes an ejection systolic high-pitched murmur, and this is due to the high velocity of systolic contraction

of the heart and the high velocity of blood moving through the aortic valve during systole.

The murmur has a crescendocendo decrescendo character, which means it speeds

up and then slows down, and this is due to the speed of blood flow across the valve during the

different periods of systolic contraction. Flow during systole is slowest at the very start and at the very end and its fastest in the middle.

The other signs of aortic stenosis are that the murmur radiates to the carotids as the turbulent blood flow continues up into the neck.

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