How to prolapse the lead into coronary sinus for left atrium pacing part 3. (A) With the sheath providing support, the stiff stylet at the proximal bend is used to advance the prolapsed lead further into the coronary sinus. The tip of the prolapsed lead is oriented towards the left atrium (medial) by advancing and withdrawing the stylet and sheath. (B) The prolapsed lead is held in place with the stylet at the proximal cant as the sheath is removed. Once the sheath is removed the stylet of the prolapsed lead is removed followed by the stylet of the left ventricular lead.