Patent ID: 7195637

Claim:
A method for inserting a lead into coronary veins of a patient, said method comprising: providing a guide sheath, said guide sheath comprising: a tube having a proximal portion and a distal portion; a lumen passing through said tube, said lumen being provided with a first opening in said proximal portion and a second opening in said distal portion and said lumen being adapted to allow the lead to pass through it; a balloon provided in said distal portion, said balloon being adapted to be inflated outwardly and circumferentially from said tube; a tubing in fluid connection with said balloon, said tubing extending from said balloon to said proximal portion; inserting said guide sheath into a coronary vein; inflating said balloon so as to prevent retrograde blood flow from the coronary vein; and inserting the lead into the coronary vein through said lumen and placing it in a target location, wherein when the balloon is inflated, retrograde blood flow from the coronary veins is prevented, the pressure in the coronary veins is increased, and the coronary veins are enlarged, allowing the lead to freely advance through them.