Anahita Dua, Bhavin Patel, Patrick Pindiur, Gary Seabrook, Peter Rossi
Medical College of Wisconsin, Milwaukee, WI.
OBJECTIVES: This study identified characteristics of patients with moderate internal carotid artery stenosis that are at increased risk for disease progression.
METHODS: Patients with asymptomatic moderate internal carotid disease (peak systolic velocity [PSV] > 125cm/sec and end diastolic velocity [EDV] < 125cm/sec by duplex ultrasonography) correlating to 50-75% diameter reduction were followed for 3 years. Progression to greater than 75% diameter reduction (EDV > 125cm/sec) or presentation with focal neurological symptoms (stroke, amaurosis fugax, transient ischemic attack [TIA]) was documented. Co-morbidities, smoking status and medications were recorded. Log-rank testing, Wilcoxon models, and Kaplan-Meier plots provided statistical analysis.
RESULTS: During 3-year follow-up, 26 (9%) of 288 patients (137 men, 151 women) developed symptoms [stroke: 9 (3.1%), TIA: 3 (1%), amaurosis fugax: 3 (1%)] or asymptomatic increase in diameter to >75% [11 (3.8%)]. All-cause mortality was 11% (33 patients). 17 patients (5.9%) underwent carotid endarterectomy and 5 (1.7%) had carotid stent placement. The event incidence was significantly higher for men (p=0.02), but survival was not different. The rate of disease progression and/or development of symptoms was 5.5% at 12 months and increased to 7.2% by 24 months. Co-morbidities with the highest associated event incidences were coronary artery disease [CAD] (8.1%), hyperlipidemia (7.3%), and hypertension [HTN] (6.7%). Medications associated with lower event incidences were insulin (2.8%) and angiotensin receptor blockers (1.9%).
CONCLUSIONS: Nine percent of patients with asymptomatic moderate carotid stenosis progressed to severe stenosis or developed ipsilateral neurological symptoms at three year follow-up. The rate of asymptomatic disease progression or symptom development was to 7.2% by 24 months. Male patients with CAD, hyperlipidemia, and HTN are at increased risk and are candidates for frequent screening and/or early intervention.
AUTHOR DISCLOSURES: A. Dua, Nothing to disclose; B. Patel, Nothing to disclose; P. Pindiur, Nothing to disclose; P. Rossi, Nothing to disclose; G. Seabrook, Nothing to disclose.
Posted April 2012