Patient Selection for Carotid Endarterectomy

Abstract

Background and Purpose-Risk-factor modeling has been proposed to identify patients with carotid stenosis who will most benefit from surgery. Validation by independent institutions performing carotid endarterectomy is necessary to determine the applicability of such models to the individual patient. Methods-A series of patients with a recently symptomatic high-grade carotid stenosis were selected for surgery according to current guidelines and were consecutively operated on in a single institution. In addition, a prognostic model was applied to the patients to analyze the concordance of both selection methods. Results-The study included 134 patients operated on between 1999 and 2001. The risk model predicted that 49% of the patients should have been excluded from surgery because the operation was found to be possibly harmful in 1 patient (1%) and not significantly beneficial in 65 patients (48%). This resulted from the predominant negative weight of the surgical risk factors in the model. However, this predominance was negated in our series by the fact that only 1 major complication (0.75%) occurred during follow-up. Key Words: carotid endarterectomy Ⅲ carotid stenosis Ⅲ patient selection Ⅲ risk assessment T he best indication for carotid endarterectomy (CEA) is a recently symptomatic high-grade carotid stenosis. 1-4 Provided that no major complication occurs during the operation, most patients find themselves efficiently protected against stroke in the following years. 5,6 The operative technique is well standardized, and the risk of restenosis is very low in experienced centers. 5 However, from an epidemiological point of view, there is a need to better select the surgical candidates because only 20% to 25% of patients medically treated have a stroke or die of stroke during the following 3 years. This means that preventive surgery remains without benefit for at least 4 of 5 operated patients. This proportion could even be increased by the ability of new statins to combat hypercholesterolemia and stabilize atherosclerotic plaques more efficiently than at the time of the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and European Carotid Surgery Trial (ECST). 7 According to current guidelines, 8,9 CEA is recommended for patients with a symptomatic high-grade stenosis when the estimated rate of perioperative complications does not exceed 6%. Because the risk of stroke is highest during the first 2 to 3 years, life expectancy should be at least 2 years when the operation is proposed. In an effort to identify the best surgical candidates, ie, patients with high risk of stroke on medical treatment alone and with low risk of operative complications and death, Rothwell et al 10 developed a prognostic model based on a balance of medical and surgical risk factors. The statistical data were gathered from 2060 ECST patients with 0% to 69% carotid stenosis. 1,2 The model was tested and validated in 990 ECST patients with 70% to 99% carotid stenosis assigned to endarterectomy (nϭ596) or medical treatment on...

Prediction Models for Clinical Outcome After a Carotid Revascularization Procedure

“…Although external validation is an essential step in prediction model development, only 4 of the 30 included models had been externally validated in an independent patient population before; 2 were externally validated in the same article in which their development was described (Alcocer 2013 and Cheng 2016), 16 , 17 and the other 2 had each been validated twice in independent validation studies (Rothwell 1999 and Tu 2003). 18 – 21 Our findings are similar to the findings of these previous studies, except that the discriminative performance of the Tu 2003 and Cheng 2016 models was slightly better in the previous external validations. A calibration plot was reported for only one of the previous external validation studies, 19 whereas we reported calibration plots for each prediction model that we validated.…”

Prediction models for clinical outcome after a carotid revascularisation procedure: A systematic review

“…Out of the 12 externally validated models, nine (75%) were solely externally validated in the same paper in which their development was described, and three (25%) were validated by independent researchers. 8 – 10 …”