Percutaneous catheter assembly

A method of percutaneous cannulation of a patient's vascular system without the need for an introducer sheath or a separate guiding catheter, said method comprising the steps of:

• placing an end cap within a proximal section of a catheter housing;
• placing a dilator through the end cap and within the catheter housing so that a distal tip of the dilator extends beyond a distal tip of the catheter housing;
• placing the catheter assembly over a guide wire within a blood vessel of the patient;
• injecting radiopaque contrast through the dilator as the dilator and catheter housing are advanced through the patient's blood vessel.

A percutaneous catheter assembly comprising:

• a catheter housing having a distal end, a proximal end, a lumen therethrough, and a catheter housing side wall having at least one perforation therein in fluid communication with said lumen to permit the passage of a contrast fluid through said perforation, said proximal end configured to connect to a standard sized blood pump;
• a dilator having a distal end, a proximal end, and at least one opening in a side wall thereof proximate the distal end of the dilator for permitting passage of the contrast fluid therethrough;
• and
• an end cap;
• wherein the dilator further comprises at least one additional opening in said dilator side wall, said side wall openings being axially positioned relative to each other such that one opening is positioned more distal than the other opening so that, when the dilator is inserted within said catheter housing, the more distal opening is positioned so that at least a part thereof projects distally beyond the distal end of the catheter housing and wherein the other opening is positioned so as to be generally radially aligned with the perforation of said catheter housing side wall.