Deployment constraining sheath that enables staged deployment by device section

Abstract

Various aspects of the present disclosure are directed toward medical devices, systems, and methods. The medical devices may include a portion having a radially expansive force greater than a radially expansive force other portions of the device. In addition, the medical device may include one or more constraining mechanisms for deployment of the medical devices.

What is claimed is: 
     
         1 . A delivery system for an expandable medical device, comprising:
 a catheter body;   an expandable medical device arranged on the catheter body, the expandable medical device including a first end portion, a second end portion, and an intermediate portion therebetween, the first end portion transitioning to the intermediate portion at a first inflection area and the second end portion transitioning to the intermediate portion at a second inflection area;   a first constraining mechanism configured to constrain at least a portion of the expandable medical device in a delivery configuration;   a deployment line coupled to the first constraining mechanism, the deployment line being operable to release the first constraining mechanism in response to tension applied to the deployment line; and   a skirt arranged about the first constraining mechanism.   
     
     
         2 . The delivery system of  claim 1 , wherein the skirt is operable to be positioned about the first constraining mechanism when the delivery system is being advanced toward a target location within a patient. 
     
     
         3 . The delivery system of  claim 1 , further comprising a distal tip positioned at a distal end of the catheter body. 
     
     
         4 . The delivery system of  claim 3 , wherein the first constraining mechanism is operable to evert from the distal tip toward a proximal end of the catheter body. 
     
     
         5 . The delivery catheter of  claim 4 , further comprising a second constraining mechanism, wherein the second constraining mechanism is positioned about the intermediate portion of the expandable medical device. 
     
     
         6 . The delivery catheter of  claim 5 , wherein the first constraining mechanism is positioned about the first end portion, the second end portion, and the intermediate portion of the expandable medical device. 
     
     
         7 . The delivery system of  claim 6 , wherein the first constraining mechanism is operable to release and deploy the first end portion and the second end portion of the expandable medical device to a fully-deployed configuration in response to release thereof. 
     
     
         8 . The delivery system of  claim 7 , wherein the second constraining mechanism constrains the intermediate portion in an intermediate configuration after release of the first constraining mechanism and the first and second end portions of the expandable medical device is in the fully-deployed configuration. 
     
     
         9 . The delivery system of  claim 8 , wherein the second constraining mechanism is arranged between the first constraining mechanism and the expandable medical device when in the delivery configuration. 
     
     
         10 . The delivery system of  claim 9 , wherein intermediate portion of the expandable medical device exerts a radially expansive force that is greater than a radially expansive force of the first and second end portions of the expandable medical device.