Atraumatic Occlusive System with Compartment for Measurement of Vascular Pressure Change

Abstract

A method of delivering a therapeutic agent into a patient vessel with a delivery device is provided. The delivery device includes an infusion lumen through which the agent is delivered, a vessel occluder that can be operated between a collapsed and an expanded configuration, and when in the expanded configuration occludes the vessel, and a pressure sensor shielded from the effects of turbulent flow at an exit of the infusion lumen. The shield pressure sensor is able to accurately sense pressure in the vessel. The sensed pressure is used to determine a dwell time for the vessel occluder in the expanded configuration.

What is claimed is: 
     
         1 . A method of delivering a therapeutic agent to a patient, comprising:
 a) providing a system for temporarily occluding a blood vessel, including,
 i) a flexible tubular member having a proximal end and a distal end, an infusion lumen extending between the proximal and distal ends, the infusion lumen having a distal orifice at the distal end, wherein when a therapeutic agent is infused through the orifice, eddy currents are generated about the orifice, and 
 ii) an expandable occluder mounted at the distal end of the tubular member, the occluder defining a chamber, the distal end of the tubular member extending through the occluder such that the orifice opens distal of the occluder, 
 iii) a first pressure sensor to sense fluid pressure in the blood vessel distal of the occluder, the first pressure sensor isolated from pressure changes induced by the eddy currents; 
   b) advancing a distal end of the system to a target vein of an organ;   c) expanding the occluder within the target vein;   d) communicating fluid between the chamber of the occluder and the target vein distal of the occluder;   e) sensing a baseline pressure in the target vein distal of the occluder;   f) delivering a therapeutic agent through the infusion lumen and out of the orifice; and   g) using the first pressure sensor to monitor pressure in the target vein distal of the occluder during the delivery.   
     
     
         2 . The method of  claim 1 , further comprising:
 using a pressure gradient between the monitored pressure and baseline pressure to determine progress of the delivery.   
     
     
         3 . The method of  claim 1 , further comprising:
 using a pressure gradient between the monitored pressure and baseline pressure to determine a dwell time in which to keep the occluder expanded within the target vein.   
     
     
         4 . The method of  claim 3 , further comprising:
 leaving the occluder expanded within the vein for at least the determined dwell time.   
     
     
         5 . The method of  claim 1 , wherein the baseline pressure is measure with the first pressure sensor prior to expanding the occluder within the vein. 
     
     
         6 . The method of  claim 1 , wherein the baseline pressure is monitored with a second pressure sensor located to sense fluid pressure in the blood vessel proximal of the occluder. 
     
     
         7 . A method of measuring pressure in a vessel distal of an artificial temporary vessel occluder delivered into the vessel, comprising:
 a) providing a system for temporarily occluding a blood vessel, including,
 i) a flexible tubular member having a proximal end and a distal end, an infusion lumen extending between the proximal and distal ends, the infusion lumen having a distal orifice at the distal end, wherein when a therapeutic agent is infused through the orifice, eddy currents are generated about the orifice, and 
 ii) an expandable occluder mounted at the distal end of the tubular member, the distal end of the tubular member extending through the occluder such that the orifice opens distal of the occluder, 
 iii) a first pressure sensor to sense fluid pressure in the blood vessel distal of the occluder, the first pressure sensor isolated from pressure changes induced by the eddy currents, and 
 iv) a second pressure sensor to sense fluid pressure in the blood vessel proximal of the occluder, the second pressure sensor isolated from the blood distal of the occluder by the occluder when the occluder is expanded across the blood vessel; 
   b) advancing a distal end of the system into a vessel;   c) communicating fluid between the chamber of the occluder and the vessel distal of the occluder;   d) sensing a baseline pressure in the vessel distal of the occluder with the first sensor;   e) sensing a baseline pressure in the vessel proximal of the occluder with the second sensor; and   f) performing a function on the data received from the first and second sensors to remove variations in the data from the first sensor due to physiological phenomena.   
     
     
         8 . A method according to  claim 7 , further comprising:
 infusing a therapeutic agent through the infusion lumen and out of the distal orifice; and   performing a function on the data received from at least the first sensor to remove variations in the data due to turbulent flow from the therapeutic agent exiting the distal orifice.   
     
     
         9 . A method of delivering a therapeutic agent into a target tissue through a vessel, comprising:
 a) providing a system for temporarily occluding a blood vessel, including,
 i) a flexible tubular member having a proximal end and a distal end, an infusion lumen extending between the proximal and distal ends, the infusion lumen having a distal orifice at the distal end, and 
 ii) an expandable occluder mounted at the distal end of the tubular member, the distal end of the tubular member extending through the occluder such that the orifice opens distal of the occluder; 
   b) advancing a distal end of the system into a vessel;   c) expanding the occluder to block blood flow past the occluder within the vessel;   d) then infusing a therapeutic agent through the infusion lumen and out of the distal orifice into the vessel distal of the occluder; and   e) leaving the occluder expanded for at least a dwell time sufficient for transport of the therapeutic agent through the vessel wall and into the target tissue.   
     
     
         10 . The method according to  claim 9 , wherein infusion of the therapeutic agent generates a pressure gradient in the vessel on the proximal and distal sides of the occluder, and the pressure gradient, at least in part, affects the transport of the therapeutic agent. 
     
     
         11 . The method according to  claim 9 , wherein the system includes a first pressure sensor to measure a first fluid pressure of blood in the vessel distal of the occluder, and a second pressure sensor to measure a second fluid pressure of blood in the vessel proximal of the occluder, and the measured pressure gradient is a differential between the first and second fluid pressures. 
     
     
         12 . The method according to  claim 9 , wherein the dwell time is calculated based, at least in part, on the diffusion rate of a molecule of the therapeutic agent. 
     
     
         13 . The method according to  claim 12 , wherein the diffusion rate of the molecule is predicted, at least in part, by the molecular mass of the molecule. 
     
     
         14 . The method according to  claim 9 , wherein one of the at least one therapeutic agent at least partially replaces the oxygen and/or nutrient requirements of the target tissue. 
     
     
         15 . The method according to  claim 9 , wherein the transport rate of the therapeutic agent is calculated, at least in part, by osmotic characteristics of the therapeutic agent in the vessel. 
     
     
         16 . The method according to  claim 9 , further comprising:
 sensing a fluid pressure in the vessel distal of the occluder,   wherein when the therapeutic agent is infused out of the orifice, eddy currents are generated about the orifice, and the system includes a pressure sensor to measure a fluid pressure in the vessel distal of the occluder, and the pressure sensor is shielded from the eddy currents.