O-035 The Dotter Technique Revisited: Early Experience using this Technique for Treating Tandem Lesions in Acute Stroke
Authors: Woodward B , Nyberg E , Wegryn S 
Published: July 2014

Objective

Carotid stenosis in the setting of anterior circulation embolic disease poses significant difficulties due to the complex nature of endovascular repair. There is ongoing debate about the benefits of initially treating distally versus proximally. However, the best method of treating proximal disease remains ambiguous. While stenting may lead to better long-term patency, this approach requires antiplatelet therapy, possibly increasing the risk of haemorrhage. At our center, a modified Dotter technique has been used in lieu of primary stenting in this setting. Using this technique for the treatment of carotid stenosis in the acute stroke setting can eliminate the need for antiplatelet therapy, reduce procedure times, and possibly reduce haemorrhagic conversion rates.

Methods

The Dotter Stroke technique is a previously unreported method for treating carotid stenosis in the acute stroke setting. First, a wire and guiding catheter or dilator are advanced across the stenosis, followed by a guiding sheath. While removing the dilator and wire, vigorous aspiration is performed. The sheath is left across the stenosis and connected to a pressurised drip. Then, intracranial thrombectomy is performed according to operator preference. After intracranial embolectomy is complete, the sheath is backed into the common carotid artery under aspiration. Repeat angiography is performed, and final stenosis is measured. Delayed angiography is performed to assure short-term patency.

From April 2013–January 2014, seven patients were identified with atherosclerotic stenosis at the carotid origin >50% and ipsilateral intracranial emboli, who presented with acute stroke and were treated using the Dotter Stroke technique. Modified Rankin and NIH Stroke scales, as well as clinical and procedural times where recorded. Pre and Post-Dotter stenosis were measured using the NASCET criteria. The final angiograms and long term non-invasive imaging were evaluated for dissection, haemorrhage, restenosis, and reintervention.

Results

The mean age was 64 years, and mean initial NIHSS was 11.7. The mean time from clinical onset to recanalization was 4 h and 5 min, with average groin to recanalization times of 26 min (14–40). TICI 2b or greater flow was achieved in all patients. The mean stenosis was 88% pre-operatively (65%–100%). After removing the sheath from ICA, post-Dotter stenosis was 61% (33%–78%). In the two subjects with the highest post-Dotter stenosis (76% and 78%), rapid re-occlusion was noted. One of these subjects had a flow limiting dissection; both were treated with bailout stenting. The remaining subjects has a post-Dotter stenosis between 33% and 65%, without re-occlusion. Average follow up is 150 days, with no haemorrhage or restenosis in any subject. There was one death in a patient with initial NIHSS of 25. The reminder had modified Rankin scales of 0 at follow-up.

Conclusion

The Dotter Stroke technique is a safe alternative to carotid stenting, and may be useful in patients at increased risk for haemorrhage. In this small series, a post-Dotter stenosis >75% is associated with re-occlusion, and stenting should be performed to prevent re-occlusion. No re-occlusion was identified at 30 days with post-Dotter stenosis <= 65%.

Disclosures

B. Woodward: None. E. Nyberg: None. S. Wegryn: None.