Indications for surgery for valve diseases Aortic stenosis Severe aortic stenosis is defined as valve area < 1 square cm and mean gradient is > 40 mm of mercury. Sometimes in severe stenosis, the valve area is < 1, but the mean gradient is only 30 to 40 (area X gradient mismatch) due to LV dysfunction ie EF < 50 %. These patients usually have contractile reserve and so with dobutamine infusion, the EF improves to > 50 % and mean gradient becomes > 40 mm Hg.
AVR (Aortic Valve Replacement) should be done in severe symptomatic aortic stenosis provided EF is at least 35% ( patient may deny symptoms and TMT may be necessary to elicit them). In severe asymptomatic patients, AVR should be done if LV dysfunction has started ie EF < 50 %. Moderate aortic stenosis is defined as mean gradient 20 to 40 mm Hg and valve area 1 to 1.5 Surgery is indicated in them, either if they have symptoms or…
