Abstract: A tubular prosthesis has a plurality of tubular rings that are radially expandable from a contracted configuration to an expanded configuration. Each ring comprises a plurality of axially oriented struts that are interconnected so as to form a circumferential series of at least one high peak and at least one low peak. The high and low peaks have apices that are oriented in the same axial direction. The apices of the high and low peaks are also oriented in the same direction and the apices of the high peaks are axially offset from the apices of the low peaks. A bridge member couples a pair of adjacent tubular rings together. The bridge member has a first end connected to a first low peak in a first tubular ring and a second end connected to either a high or low peak in an adjacent tubular ring.

Abstract: A tubular prosthesis has a plurality of tubular rings that are radially expandable from a contracted configuration to an expanded configuration. Each ring comprises a plurality of axially oriented struts that are interconnected so as to form a circumferential series of at least one high peak and at least one low peak. The high and low peaks have apices that are oriented in the same axial direction. The apices of the high and low peaks are also oriented in the same direction and the apices of the high peaks are axially offset from the apices of the low peaks. A bridge member couples a pair of adjacent tubular rings together. The bridge member has a first end connected to a first low peak in a first tubular ring and a second end connected to either a high or low peak in an adjacent tubular ring.

Abstract: A catheter introduces electrodes in a vein for a minimally invasive treatment of venous insufficiency by the application of energy to cause selective heating of the vein. The catheter is positioned within the vein to be treated, and the electrodes on the catheter are moved toward one side of the vein. RF energy is applied in a directional manner from the electrodes at the working end of the catheter to cause localized heating and corresponding shrinkage of the adjacent venous tissue, which may include commissures, leaflets and ostia. Fluoroscopy or ultrasound may be used to detect shrinkage of the vein. After treating one section of the vein, the catheter can be repositioned to place the electrodes to treat different sections of the vein until all desired venous valves are repaired and rendered functionally competent.

Abstract: A coil is located at the distal working end of an electrode catheter. The coil includes two parallel electrically conductive strips separated by a narrow gap. The strips are covered with insulation, and are connected respectively to electrical leads having opposite polarity. Electrodes are formed by removing portions of the insulation from the strips. The coil can be expanded to define an increased effective diameter at the working end of the catheter. An RF field produced along the helical path defined by the strips of the coil is unaffected by the expanded state of the coil. The energy from the RF field heats the surrounding venous tissue and causes a reduction in the diameter of the vein. The expanded coil mechanically prevents the vein from shrinking beyond the effective diameter defined by the expanded coil and the patency of the vein is maintained for venous function.