An intravascular device, the device comprising: an elongated body having a proximal end, a distal end, a longitudinal axis , and a body radius , at least part of the elongated body being made of a body material and having a length between the proximal end and the distal end, and the body radius being (i) measured from the longitudinal axis of the elongated body to an outer surface of the body when the elongated body has a circular transverse cross-section, and (ii) approximated as the average distance from the longitudinal axis to an outer surface of the body when the elongated body has a non-circular transverse cross-section; a major lumen defined by the elongated body and extending from the proximal end to the distal end; a plurality of minor lumens defined by the elongated body and extending from the proximal end through at least a portion of the length of the elongated body , each of the plurality of minor lumens being fixed relative to the major lumen in transverse cross-section and separated therefrom by a portion of the body that defines a lumen wall ; and a reinforcement layer connected to the elongated body , the reinforcement layer including a reinforcement material having a greater elastic modulus than the body material, characterized in that a ratio of the thickness of the lumen wall relative to the body radius is within the range from 0.100 to 0.150. an elongated body having a proximal end, a distal end, a longitudinal axis , and a body radius , at least part of the elongated body being made of a body material and having a length between the proximal end and the distal end, and the body radius being (i) measured from the longitudinal axis of the elongated body to an outer surface of the body when the elongated body has a circular transverse cross-section, and (ii) approximated as the average distance from the longitudinal axis to an outer surface of the body when the elongated body has a non-circular transverse cross-section; at least part of the elongated body being made of a body material and having a length between the proximal end and the distal end, and the body radius being (i) measured from the longitudinal axis of the elongated body to an outer surface of the body when the elongated body has a circular transverse cross-section, and (ii) approximated as the average distance from the longitudinal axis to an outer surface of the body when the elongated body has a non-circular transverse cross-section; (i) measured from the longitudinal axis of the elongated body to an outer surface of the body when the elongated body has a circular transverse cross-section, and (ii) approximated as the average distance from the longitudinal axis to an outer surface of the body when the elongated body has a non-circular transverse cross-section; a major lumen defined by the elongated body and extending from the proximal end to the distal end; a plurality of minor lumens defined by the elongated body and extending from the proximal end through at least a portion of the length of the elongated body , each of the plurality of minor lumens being fixed relative to the major lumen in transverse cross-section and separated therefrom by a portion of the body that defines a lumen wall ; and a reinforcement layer connected to the elongated body , the reinforcement layer including a reinforcement material having a greater elastic modulus than the body material, characterized in that a ratio of the thickness of the lumen wall relative to the body radius is within the range from 0.100 to 0.150. <EOS>