title: Next generation catheters for excimer laser coronary angioplasty.
abstract: In response to the need for maximising debulking in complex lesions, three new excimer laser coronary angioplasty catheter designs have been introduced. The eccentric laser catheter features a fibreoptic bundle disposed opposite the guide-wire lumen at the catheter tip and a torque mechanism that allows the user to rotate the fibre bundle toward the lesion mass. Residual lumens 50% larger than the catheter tip diameter have been obtained when multiple passes were made, with each pass performed using a different tip rotation. A recent case series utilising this catheter in restenosed stents resulted in larger lumens and lower 6-month restenosis rates. The optimal spaced (OS) laser catheter features a fibre bundle placed concentrically around the guide-wire lumen. The 61 microm diameter core fibres are spaced at a nominal centre-to-centre distance of 90 microm, resulting in a 40% increase in ablative area as compared to previous concentric catheter designs. In vitro testing and clinical evaluation demonstrated OS catheters routinely achieve an ablated area > or =90% of the catheter tip size. The 0.9 mm catheter features a high-density fibre pack composed of 65 fibres. Peripheral dead space has been minimised to maximise penetration of calcified plaque. When combined with laser parameters of up to 80 mJ/mm2, and 80 Hz pulse repetition rate, the catheter demonstrated improved hard tissue and calcified tissue penetration in vitro. Clinical evaluation in Canada revealed a 94% lesion recanalisation rate in high-grade stenoses with angiographic evidence of calcification, chronic total occlusions, and lesions which have failed balloon angioplasty.
authors.affiliation: Spectranetics, Colorado Springs, CO 80907, USA. kevin.taylor@spectranetics.com
authors.forename: K
authors.initials: K
authors.lastname: Taylor
authors.forename: C
authors.initials: C
authors.lastname: Reiser
mesh_terms: D016342:Angioplasty, Laser / Q000295:instrumentation*; D002404:Catheterization; D003327:Coronary Disease / Q000601:surgery*; D006801:Humans