Stroke rates after carotid artery stenting depend on study-specific definitions
Stephan Staubach1, Katharina Soekeland, Jakob Ledwoch
1Klinik für Kardiologie, Pneumologie und Internistische Intensivmedizin, Städtisches Klinikum München GmbH, Klinikum Neuperlach, Munich, Germany.
Summary
Stroke definitions vary, impacting trial results. This study found substantial agreement between definitions, but standardized criteria are needed for future stroke research comparing carotid artery stenting (CAS) and endarterectomy (CEA).
Area of Science:
- Neurology
- Vascular Surgery
- Clinical Trials
Background:
- There is no universally accepted definition for minor and major stroke in clinical trials comparing carotid artery stenting (CAS) and carotid endarterectomy (CEA).
- This variability in definitions can lead to discrepancies in reported stroke rates and complicate comparisons between studies.
Purpose of the Study:
- To categorize procedure-related strokes as minor or major based on study-specific definitions within a large single-center CAS registry.
- To assess the agreement between different stroke definitions used in trials comparing CAS and CEA.
Main Methods:
- Neurological assessments were performed pre- and post-procedurally by a neurologist, using the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS).
- Patients undergoing 947 CAS procedures were analyzed for neurological events occurring within 30 days.
- Fleiss' Kappa and Cohen's Kappa tests were employed to compare stroke rates across various definitions.
Main Results:
- A total of 34 neurological events (3.6%) were recorded within 30 days post-procedure.
- Using the study's definition, 15 patients (1.6%) experienced a major stroke and 19 (2%) a minor stroke.
- A substantial agreement (Fleiss' Kappa = 0.73) was observed when comparing different stroke definitions, although stroke rates varied significantly depending on the definition used.
Conclusions:
- Study-specific definitions for minor and major strokes significantly influence reported stroke rates in trials comparing CAS and CEA.
- It is crucial to respect these study-specific definitions when comparing trial outcomes.
- The adoption of a standardized definition for minor and major stroke is recommended for future clinical trials to enhance comparability and reduce ambiguity.
