Techniques: operation is done under general endo tracheal anaesthesia. Patient is positioned with the left chest tilted up using a sand bag under left chest. Left antero lateral thorocotomy is done through 5" intercostals space. Pericardium is opened two cm in front of phrenic nerve stay sutures are taken. Pulmonary artery pressure is assessed by palpation. A vertical mattress suture is applied above the LV apex in an avascular area. Ventricular epicardium is incised and an opening is made in the LV. It is controlled by a snare by passing the threads through it. A purse string is applied a little anterior to the base of left atrial appendage. Before applying a clamp on she left atrial appendage, it is opened momentarily to let out blood and any clot present inside the appendage. Surgeon inserts the right index finger through the left atrial appendage incision and mitral valve is palpated and assessed for size of the orifice, calcification and degree of regurgitation. The actual valvotomy is done by a Tubb's dillator inserted in a closed position, through the previously made ventriculotomy. The Tubb's dilator handle a mechanism to open the two blades to the desired amount by a screw arrangement, Before insertion, the opening is adjusted to 2.25 cms by using a scale. The dilator is then inserted into LV with left hand and guided to LA through the tight mitral orifice by the right index finger in LA. By pressing the handle with the left hand the dilator opens to desired amount and the valve opens up. The dilutor blades are positioned against the valve cusps and not the commissures. Tile dilator is removed 2^nd further gradual dilatations are done by adjusting the dilator lo 2.5, 2.75, 3, 3.25 01. 3:5 cms and repeating the dilatations until the valve opens up without producing significant regurgitation. The finger is removed. Left atrial appendage and L V apical incision are sutured. Usually the pulmonary artery becomes softer. Pericardium is closed with intermpted sutures and chest closed in layers after inserting a single chest drain. If there is significant pulmonary arterial hypertension, patient is ventilated for a few hou1-s or over night.