Retrograde venous cardioplegia catheters and methods of use and manufacture

A catheter for performing retrograde venous cardioplegia by delivering a cardioplegic solution into the coronary sinus of the heart, the catheter comprising:

• a flexible, dual lumen cannula of a size capable of insertion into the coronary sinus of the heart, said cannula having an infusion lumen and a sensing lumen;
• a balloon attached to the cannula periphery near the distal end of the cannula, thereby forming a chamber between the balloon and the cannula;
• at least one balloon aperture in the infusion lumen positioned such that the infusion lumen is in communication with the chamber formed by the balloon and the cannula through the at least one balloon aperture;
• at least one infusion lumen outlet in the infusion lumen positioned between the balloon and the distal end of the cannula such that, when cardioplegic solution passes through the infusion lumen, a portion of the cardioplegic solution enters the chamber through the at least one balloon aperture and a portion of the cardioplegic solution exits the infusion lumen outlet, the aggregate of said infusion lumen outlets having a total cross-sectional area which is less than the total cross-section areas of the aggregate of said balloon apertures in the infusion lumen, thereby creating a pressure within the infusion lumen which causes the cardioplegic solution to enter the chamber through the at least one balloon aperture in order to fill the balloon until it is turgid and in sealing engagement with the walls of the coronary sinus;
• at least one sensing lumen orifice in the sensing lumen located at a point between the balloon and the distal end of the cannula which is remote from the at least one infusion lumen outlet, said sensing lumen orifice having a cross-sectional area greater than the cross-sectional area of the sensing lumen;
• and
• a stylet removably positioned within the flexible cannula, said stylet having a handle at the proximal end thereof and a predetermined curve at the distal end thereof, said stylet being constructed of a rigid material such that the stylet can be used to position the flexible cannula in the coronary sinus with minimal trauma to the heart tissues.

A catheter for performing retrograde venous cardioplegia by delivering a cardioplegic solution into the coronary sinus of the heart, the catheter comprising:

• a flexible, dual lumen cannula of a size capable of insertion into the coronary sinus of the heart, said cannula having an infusion lumen and a sensing lumen;
• a tip located at the distal end of the cannula such that the distal ends of the infusion lumen and the sensing lumen are occluded at the tip, the tip being configured and made of a material such that trauma to the coronary sinus is minimized during insertion of the cannula;
• a balloon attached about and to the cannula periphery near the distal end of the cannula, thereby forming a chamber between the balloon and the cannula, said balloon being tapered from the distal end to the proximal end of the balloon, thereby minimizing trauma during the insertion of the cannula into the coronary sinus and thereby encouraging sealing engagement of the balloon with the walls of the coronary sinus;
• a plurality of balloon apertures in the infusion lumen positioned such that the infusion lumen is in communication with the chamber formed by the balloon and the cannula through the balloon apertures, the aggregate of said balloon apertures having a total cross-sectional area in the range from about 1.5 to about 5 times the cross-sectional area of the infusion lumen;
• a plurality of infusion lumen outlets in the infusion lumen positioned between the balloon and the distal end of the cannula such that, when cardioplegic solution passes through the infusion lumen, a portion of the cardioplegic solution enters the chamber through the balloon apertures and a portion of the cardioplegic solution exits the infusion lumen and the cannula through the infusion lumen outlets, the aggregate of said infusion lumen outlets having a total cross-sectional area which is in the range from about twenty-five to about seventy-five percent cross-section area of the infusion lumen, thereby creating a pressure within the infusion lumen which causes the cardioplegic solution to enter the inner chamber through the balloon apertures in order to fill the balloon until it is turgid and in sealing engagement with the walls of the coronary sinus;
• at least one sensing lumen orifice in the sensing lumen located at a point between the balloon and the distal end of the cannula which is remote from the at least one infusion lumen outlet, said sensing lumen orifice having a cross-sectional area greater than the cross-sectional area of the sensing lumen;
• and
• a stylet removably positioned within the flexible cannula, said stylet having a handle at the proximal end thereof, and a predetermined curve at the distal end thereof, said stylet being constructed of a rigid material such that the stylet can be used to position the flexible cannula in the coronary sinus with minimal trauma to the heart tissue.

A method for the retrograde administration of a cardioplegic solution into the coronary sinus of the heart, the method comprising the steps of:

• inserting a catheter through a small incision in the right atrium, said catheter comprising:
• a cannula having an infusion lumen with at least one infusion lumen outlet near its distal end such that cardioplegic solution can be introduced into and passed through the cannula and exit the outlet, said cannula also having a sensing lumen with a sensing lumen orifice near its distal end having a cross-sectional area greater than the cross-sectional area of the sensing lumen;
• a self-filling balloon secured about the cannula at a point proximal of the at least one infusion lumen outlet such that as cardioplegic solution passes through the cannula, a portion of the cardioplegic solution fills the balloon and a portion exits the cannula through the outlet;
• and
• a removable curved stylet located within the cannula, said stylet being constructed of a rigid material;
• manipulating the stylet to position the catheter within the coronary sinus such that the balloon, when filled with cardioplegic solution, will be in engagement with the walls of the coronary sinus:
• securing the catheter in place in order to minimize longitudinal movement of the balloon and outlet of cannula within the coronary sinus;
• withdrawing the stylet from within the catheter;
• and
• injecting cardioplegic solution through the cannula at sufficient pressure such that the balloon fills to sealingly engage the walls of the coronary sinus, thereby permitting retrograde administration of the cardioplegic solution.

A catheter for performing retrograde venous cardioplegia by delivering a cardioplegic solution into the coronary sinus of the heart, the catheter comprising:

• a flexible, dual lumen cannula of a size capable of insertion into the coronary sinus of the heart, said cannula having an infusion lumen and a sensing lumen;
• a balloon attached to the cannula periphery near the distal end of the cannula, thereby forming a chamber between the balloon and the cannula;
• at least one balloon aperture in the infusion lumen positioned such that the infusion lumen is in communication with the chamber formed by the balloon and the cannula through the at least one balloon aperture, the aggregate of said balloon apertures having a total cross-sectional area which is greater than the cross-sectional area of the infusion lumen;
• at least one infusion lumen outlet in the infusion lumen positioned between the proximal end of the balloon and the distal end of the cannula such that, when cardioplegic solution passes through the infusion lumen, the size and configuration of the at least one infusion outlets creates a pressure within the infusion lumen which cause the cardioplegic solution enters the chamber through the at least one balloon aperture in a order to fill the balloon until it is turgid and in sealing engagement with the walls of the coronary sinus;
• and
• at least one sensing lumen orifice in the sensing lumen located at a point proximal of the distal end of the cannula which is remote from the at least one infusion lumen outlet, the aggregate of said sensing lumen orifices having a cross-sectional area greater than the cross-sectional area of the sensing lumen.

A method for the retrograde administration of a cardioplegic solution into the coronary sinus of the heart, the method comprising the steps of:

• (a) inserting a catheter through a small incision in the right atrium, said catheter comprising:
• a cannula having an infusion lumen with at least one infusion lumen outlet near its distal end such that cardioplegic solution can be introduced into and passed through the cannula and exit the outlet, said cannula also having a sensing lumen with at least one sensing lumen orifice near its distal end, the aggregate of said sensing lumen orifices having a total cross-sectional area greater than the cross-sectional areas of the sensing lumen;
• a self-filling balloon secured about the cannula at a point proximal of the at least one infusion lumen outlet such that as cardioplegic solution passes through the cannula, a portion of the cardioplegic solution fills the balloon and a portion exits the cannula through the outlet;
• and
• a removable curved stylet located within the cannula;
• (b) manipulating the stylet to position the catheter within the coronary sinus such that the balloon, when filled with cardioplegic solution, will be in engagement with the walls of the coronary sinus;
• (c) securing the catheter in place in order to minimize longitudinal movement of the balloon and outlet of cannula within the coronary sinus;
• (d) withdrawing the stylet from within the catheter;
• and
• (e) injecting cardioplegic solution through the cannula at sufficient pressure such that the balloon fills to sealingly engage the walls of the coronary sinus, thereby permitting retrograde administration of the cardioplegic solution.

A catheter for performing retrograde venous cardioplegia by delivering a cardioplegic solution into the coronary sinus of the heart, the catheter comprising:

• a flexible, cannula of a size capable of insertion into the coronary sinus of the heart, said cannula having an infusion lumen and a sensing lumen;
• a balloon attached to the cannula periphery near the distal end of the cannula, thereby forming a chamber between the balloon and the cannula;
• at least one balloon aperture in the infusion lumen positioned such that the infusion lumen is in communication with the chamber formed by the balloon and the cannula through the at least one balloon aperture;
• at least one infusion lumen outlet in the infusion lumen positioned between the proximal end of the balloon and the distal end of the cannula such that, when cardioplegic solution passes through the infusion lumen, the size and configuration of the at least one infusion outlets creates a pressure within the infusion lumen which causes the cardioplegic solution enters the chamber through the at least one balloon aperture in a order to fill the balloon until it is turgid and in sealing engagement with the walls of the coronary sinus;
• at least one sensing lumen orifice in the sensing lumen located at a point proximal of the distal end of the distal end of the cannula which is remote from the at least one infusion lumen outlet, the aggregate of said sensing lumen orifices having a cross-sectional area greater than the cross-sectional area of the sensing lumen;
• and
• a stylet removably positioned within the flexible cannula, said stylet having a handle at the proximal end thereof and a predetermined curve at the distal end thereof, said stylet handle having a finger loop extending from the distal end of the stylet handle and a thumb rest located at the proximal end of the stylet handle.