Combination Therapies—Especially Thrombolytics and Adjunctive Medications

3:45 p.m. Combination Therapies-Especially Thrombolytics and Adjunctive Medications Kenneth Ouriel, MD, and Roy K. Greenberg, MD The Cleveland Clinic Foundation Cleveland, Ohio In the quest for less invasive interventions in health care overall, the setting of acute peripheral arterial occlusion offers a setting where the patient is likely to benefit. The rates of morbidity and mortality with standard open surgical intervention remain high. Thus, a more aggressive use of urgent surgery is clearly not the answer; rather, improvements in less invasive percutaneous modalities are more likely to achieve improved clinical outcome. In this regard, the following issues must be addressed in a systematic fashion if true benefits are likely to be realized: 1. More rapid dissolution of thrombus. Present techniques require, on the average, 24 hours of intraarterial administration of thrombolytiC agent (13). Patients must be transferred to an intensive care unit setting in most institutions, with multiple trips to the angiography suite to assess the progress of thrombolysis. Newer agents, possibly ones that do not rely on plasminogen or the addition of glycoprotein (GP) lIb/IlIa platelet antagonists, might quicken thrombolysis to the point where the infusions can be completed within 8 hours. Devices such as the mechanical thrombectomy catheters hold the potential to further decrease the time required for thrombus removal, possibly to the point where treatment can be completed during a single visit to the angiography suite. 2. Decrease in the rate of bleeding complications. Newer agents may be associated with a reduction in bleeding, especially those that a rapid enough to achieve more rapid thrombolysis and limit the duration of exposure to the agent to several hours. Further, mechanical thrombectomy devices and GP IIb/ IIIa antagonists may allow the use of lower doses of thrombolytic agents over a shorter period of time. 3. Decrease the rate of distal embolization. More rapid dissolution of occlusive thrombus is, unfortunately, associated with an obligatory increase in the risk of distal embolization as the clot breaks up into macroscopic particles. Emboli protection devices have been successfully employed in the carotid and coronary circulations. With some design modifications, similar devices are attractive for peripheral indications. The GP IIb/IIIa antagonists may provide some protection in this regard, as has been suggested in the setting of carotid angioplasty/stenting. 4. More durable means to address culprit lesions. To date, the results of percutaneous infrainguinal modalities such as angioplasty and stenting have been disappointing. With the use of newer devices and antithrombotic agents such as the GP IIb/IIIa antagonists,

however, the long-term clinical success should improve. Such improvements will decrease the necessity of repeated reinterventions for failure of the primary therapy and provide substantial decreases in morbidity and the utilization of healthcare resources. Upcoming clinical trials should proVide additional insight into many of these issues, evaluating a variety of pharmacologic and mechanical treatment strategies for peripheral arterial and bypass graft occlusion. Hopefully, the acquisition of sound data will provide clinicians with sound rationale on which to base patient care decisions and, in the end, may effect a decrease in the rate of morbid complications following acute peripheral arterial occlusion.

Monday, April 8, 2002 3:15 p.m.-4:45 p.m. Coordinator: John H. Rundback, MD Moderator: Krishna Kandarpa, MD, PhD

Objectives: Upon completion of this course, the attendee should be able to: 1. Have a basic understanding of how to organize a clinical research program. 2. Organize, create, and initiate a research protocol. 3. Identify available funding sources and mechanisms to support research development. 3:15 p.m. Current Status of VIR Research: What Needs to be Done? john H. Rundback, MD New York Pl"esbyterian Hospital/Columbia New York, New York Methodology Early in 2001, a survey was created by the CIRREf research committee (RC) co-chairs with input from RC membership, CIRREF leadership, and SCYlR/ClRREF staff. The survey was piloted in April 2001 and subsequently disseminated to the SCYlR US membership. This outline provides preliminary survey results. Purpose There were several purposes to the research survey, with the global objective of identifying the current status of research interest and activity in the VIR community: • Determine demographics of IR research practice • Identify reasons that limit IRs participating in or developing research initiatives • Collect current clinicaVresearch activity and interests in specific project areas • Collation of members' research expertise and interests, procedure volume, training (fellowship, re-

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