Synergies in a Cypher Sirolimus-eluting Coronary Stent World

Suggested Guiding Catheter Characteristics Drug-eluting stents are now the gold standard for treating obstructive coronary artery disease intravascularly. Several guiding catheter characteristics prove to be invaluable in delivering these devices to the target lesion. During multiple device exchanges and cases that require treating difficult to reach or cross lesions, stability of the guiding catheter is of paramount importance. In such cases, catheter shapes that provide extra backup are recommended. Amplatz, XB, and other extra backup style shapes offer support that JL or JR guides cannot approach. When attempting to deliver interventional devices distally, shorter length guides are often the solution because they allow the operator to utilize more of the SDS working zone to reach distally. Furthermore, when less traumatic active engagement is desired, a long soft radiopaque distal tip is often required. A long soft tip minimizes engagement trauma as well as intra-procedure trauma during multiple exchanges and when deep seating of the guide for added support is necessary. Use of a Marker Wire Delivering drug-eluting stents also requires meticulous measurement of the treatment area to ensure that stenting is done from healthy endothelium to healthy endothelium. The consequence of geographically missing even part of the treatment area reduces the probability of minimizing restenosis. Appropriate utilization of a marker wire may assist in stent placement and help to ensure proper stent placement. In smaller, more tortuous lesions and during the delivery of longer stents where cine foreshortening is more likely to occur, marker wires help to ensure proper drug-eluting stent length measurement. The reduced potential of multiple stent placements due to inadequate selection of the first stent is also a compelling economic value that comes with marker wire use. An evaluation study by the Scripps Clinic on the Use of ATW Marker Wire to Guide Choice of Stent Length assessed a series of 51 consecutive lesions. Initially, the lesions were visually estimated, and then were reevaluated with the assistance of a marker wire. In over 25% (13/51) of the cases, the calibrated guide wire altered the stent length chosen. In 12 of the 13 cases, the stent length chosen following marker wire placement was longer than that which had been originally chosen prior to placement of the marker wire. Overall, the study determined that marker wires may be of aid in percutaneous intervention with stenting by providing an objective means of determining the appropriate stent or balloon length prior to deployment of the device.¹ Balloon Use There are also key PTCA dilatation catheter characteristics, which are of utmost importance in delivering drug-eluting stents. It is indispensable that careful attention be observed to minimize vessel wall injury, perhaps with the use of balloons slightly shorter than the stent to minimize trauma outside of the implanted stent. To minimize the risk of geographic miss and its resultant potential for peri-stent restenosis, the use of shorter balloons is recommended during pre and post-dilatation. Avoiding balloon melon-seeding during inflation, therefore minimizing tissue injury, can also be achieved by using shorter balloons with no hydrophilic coating. Another technique which may be employed to minimize tissue damage is choosing balloons with steeper transition angles, which ensure more focal dilatation. Finally, warranting appropriate stent-wall apposition can be achieved by utilizing a low-compliant or non-compliant balloon shorter than the stent for post dilatation. Confirming stent-wall apposition by IVUS can never be overused. Final Thoughts The emergence of coronary drug-eluting stents requires an even greater need for synergy between the stent and a supporting cast of non-stent delivery technologies. It is up to the interventional cardiologist to make the best use of supporting technologies and techniques that maximize both procedural outcomes and patient quality of life. Extra guide support, shorter length guides, long soft-tip guides, marker wires, short balloons with no hydrophilic coating, and appropriate utilization of IVUS are the clinically invaluable resources that help to optimize these outcomes.

1. Reilly JP, Grise M, Moussavian M, Teirstein P. Use of ATW Marker Wire to Guide Choice of Stent Length. Am J Cardiol2001; 88 (supp1 5A).