Surgery for a stenosed valve could be either opening up the valve surgically or replacing the valve with an artificial one. Surgery for opening up a stenosed (narrowed) mitral valve could be either closed mitral valvotomy (a closed heart procedure) or open mitral valvotomy (an open heart procedure requiring the use of a heart lung machine). In case of other valves like aortic and pulmonary valves, valvotomy is usually an open heart procedure. Valve replacements are also open heart procedures.
But now a days, closed or open mitral valvotomy is seldom done. Instead a catheter based interventional procedure known as balloon mitral valvotomy is preferred. In this case there is no surgical scar left behind and the hospital stay is only a couple of days. Pulmonary and aortic valvotomy can also be done by catheter based techniques. Balloon catheters (small tubes with an inflatable balloon at the tip) are used for all these procedures. Aortic valve replacement can also done with a catheter based technique known as TAVI (trans-catheter aortic valve implantation).