Embolic Protection

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Citation
US Cardiology, 2007;4(1):77-8

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After having performed angioplasty in coronary and peripheral vascular disease with excellent results, carotid angioplasty was thought to be an opportunity to simplify the treatment of carotid stenosis. Up until then there was no apparent reason to protect patients against distal embolisation. With the development of carotid angioplasty and stenting, prevention of distal embolisation of arteriosclerotic debris and thrombus became a main focus of the intervention. Studies using transcranial Doppler proved that carotid stenting procedures were associated with a significantly higher incidence of debris dislodgment compared with surgical endarterectomy procedures.
To establish stenting as an alternative to surgery, various embolic protection devices have been developed over the last few years. The first device was described in 1990 by Theron.1 This was a triple coaxial catheter with a small latex balloon at the tip of a microcatheter. Nowadays there are three different types of devices available: filter devices, proximal occlusion devices and distal occlusion devices.
The invention and improvement of low-profile devices, together with the experience of the interventionalists, led to lower complication rates shown in several trials and clinical series. There has been little interest in conducting randomised trials to examine carotid stenting without embolic protection versus with embolic protection devices. Most physicians believe that the debris that can be seen in the filters is evidence enough. Another explanation is that the complication rate of carotid interventions without embolic protection devices is already low (less than 5%), which means a large number of procedures would be necessary to prove the benefit of these devices. During the endarterectomy versus angioplasty (EVA)-3S trial, the safety committee recommended stopping unprotected carotid angioplasty and stenting (CAS) because the 30-day rate of stroke was 3.9 (0.9–16.7) times higher than that of CAS with cerebral protection (4/15 versus 5/58).2,3
The World Registry described a 30-day stroke/death rate of 4.2% in patients without distal protection and of 1.7% in carotid procedures with protection.4 Kastrup et al. performed a meta-analysis of carotid trials between 1990 and 2002 with a total of 2,537 procedures performed without protection and 896 procedures performed with an embolic protection device. The combined stroke/death rate at 30 days in patients with cerebral protection was 1.8% compared with 5.5% in patients treated without protection.5 The Arbeitsgemeinschaft Leitende Kardiologische Krankenhausärzte (ALKK) German registry examined the results of 1,483 carotid procedures, in 45% of which embolic protection was used.

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References
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