Reporting Standards for Carotid Artery Angioplasty and Stent Placement

Background and Purpose— Cerebrovascular disease is the third leading cause of death in the United States. Approximately 750 000 people have a stroke annually, costing an estimated $45 to $50 billion in treatment and lost productivity according to the National Institutes of Health. Carotid occlusive disease is responsible for 20% to 25% of these strokes. Surgical carotid endarterectomy is currently the accepted standard of treatment for revascularization of extracranial carotid occlusive disease. This has been validated by multiple, randomized, controlled clinical trials that have demonstrated its efficacy over best medical therapy in North America and Europe. However, in the past several years, carotid artery stenting has emerged as a potential therapeutic alternative to surgical carotid endarterectomy for the treatment of atherosclerotic carotid artery disease. The future status of this endovascular approach will be determined by well designed, randomized, multicenter trials directly comparing carotid artery stenting to surgical endarterectomy, as well as by the potential for further innovation and improvement in endovascular devices, techniques, and safety. Comparisons of carotid artery stenting and endarterectomy are difficult because of differences in patient selection, the use of case series rather than randomized controlled trials for stenting, differences in definitions of outcomes and complications, and observer bias. The suggested reporting standards for carotid endarterectomy have not been uniformly followed-up for surgical trials and have also not been used in trials of carotid artery stenting. It is the purpose of this document to standardize the reporting of carotid stent trials and to recommend trial designs so that carotid stenting and endarterectomy may be fairly compared. This document is a consensus statement of the Technology Assessment Committees of the American Society of Interventional and Therapeutic Neuroradiology and the Society of Interventional Radiology. Methods— This article was written under the auspices of the Technology Assessment Committees for the American Society of Interventional and Therapeutic Neuroradiology and the Society of Interventional Radiology. The purpose of this document is to provide guidance for the ongoing study design of trials of carotid artery revascularization using endovascular methods including stent-supported angioplasty and use of endovascular protection devices during the procedure. It also serves as a background for the previous surgical carotid endarterectomy trials in North America and Europe. It also gives results of the current carotid angioplasty and stenting published studies, discusses limitations of various endovascular methods, defines predictors for success, and offers the rationale for the different considerations that might be important during the design of a clinical trial for stent-angioplasty for treatment of carotid atherosclerotic stenosis. Included in this guidance document are suggestions for uniform reporting standards. These definitions and standards are mainly intended for research trials; however, they should also be helpful in clinical practice and applicable to all scientific publications. This article serves to standardize reporting terminology and includes pretreatment assessment, neurological evaluation, imaging evaluation, stenosis assessment and quantification, follow-up imaging studies, and posttreatment neurological and cardiac assessments. Moreover, previously used and established definitions for patient selection, outcome assessment, and data analysis are provided, with specific end points. This document is, therefore, targeted to help an investigator to critically review the scales and scores used previously in carotid revascularization trials and studies. This article also seeks to standardize patient selection for treatment based on neurological condition at presentation, baseline imaging studies, and use of standardized inclusion/exclusion criteria. It defines outcomes from therapy in past surgical and endovascular series. A discussion on techniques for angiography, stent-angioplasty, anticoagulation, adjuvant therapy, and patient management after therapy is given, as well as recommendations for posttreatment evaluation, duration of follow-up, and reporting of disability outcomes. The final section details reporting standards for complications and adverse outcomes; defines serious adverse events, adverse events, and unanticipated adverse events; and describes severity of complications and their relation to treatment groups. Conclusion— In summary, this article serves to provide a more uniform set of criteria for clinical trials and reporting outcomes used in designing carotid revascularization trials including angioplasty and stent-supported angioplasty, either alone or in combination with other therapies such as distal vascular filtration devices. It is anticipated that by having a more uniform set of reporting standards, more meaningful analysis of the data and the literature will be able to be achieved.