Endovascular Thrombectomy of Calcified Emboli in Acute Ischemic Stroke: A Multicenter Study

BACKGROUND AND PURPOSE

Large intracranial vessel occlusion due to calcified emboli is a rare cause of major stroke. We assessed the prevalence, imaging appearance, the effectiveness of mechanical thrombectomy, and clinical outcome of patients with large-vessel occlusion due to calcified emboli.

MATERIALS AND METHODS

We performed a retrospective analysis of clinical and procedural data of consecutive patients who underwent mechanical thrombectomy due to calcified emboli in 7 European stroke centers.

RESULTS

We screened 2969 patients, and 40 patients matched the inclusion criteria, accounting for a prevalence of 1.3%. The mean maximal density of the thrombus was 327 HU (range, 150-1200 HU), and the mean thrombus length was 9.2 mm (range, 4-20 mm). Four patients had multiple calcified emboli, and 2 patients had an embolic event during an endovascular intervention. A modified TICI score of ≥2b was achieved in 57.5% (23/40), with minimal-to-no reperfusion (modified TICI 0-1) in 32.5% (13/40) and incomplete reperfusion (modified TICI 2a) in 10% (4/40). Excellent outcome (mRS 0-1) was achieved in only 20.6%, functional independence (mRS 0-2) in 26.5% and 90-day mortality was 55.9%.

CONCLUSIONS

Acute ischemic stroke with large-vessel occlusion due to calcified emboli is a rare entity in patients undergoing thrombectomy, with considerably worse angiographic outcome and a higher mortality compared with patients with noncalcified thrombi. Good functional recovery at 3 months can still be achieved in about a quarter of patients.

Emergency Stenting of the Extracranial Internal Carotid Artery in Combination with Anterior Circulation Thrombectomy in Acute Ischemic Stroke: A Retrospective Multicenter Study

BACKGROUND AND PURPOSE

Several small case series reported a favorable clinical outcome for emergency stent placement in the extracranial internal carotid artery combined with mechanical thrombectomy in acute stroke. The rate of postinterventional symptomatic intracranial hemorrhages was reported to be as high as 20%. Therefore, we investigated the safety and efficacy of this technique in a large multicentric cohort.

MATERIALS AND METHODS

The data bases of 4 German stroke centers were screened for all patients who received emergency stent placement of the extracranial internal carotid artery in combination with mechanical thrombectomy of the anterior circulation between 2007 and 2014. The primary outcome measure was the rate of symptomatic intracranial hemorrhage according to the European Cooperative Acute Stroke Study III criteria; secondary outcome measures included the angiographic revascularization results and clinical outcome.

RESULTS

One hundred seventy patients with a median age of 64 years (range, 25-88 years) were treated. They presented after a median of 98 minutes (range, 52-160 minutes) with a median NIHSS score of 15 (range, 12-19). Symptomatic intracranial hemorrhages occurred in 15/170 (9%) patients; there was no statistically significant difference among groups pertaining to age, sex, intravenous rtPA, procedural timings, and the rate of successful recanalization. In 130/170 (77%) patients, a TICI score of ≥ 2b could be achieved. The in-hospital mortality rate was 19%, and 36% of patients had a favorable outcome at follow-up.

CONCLUSIONS

Emergency stent placement in the extracranial internal carotid artery in combination with anterior circulation thrombectomy is effective and safe. It is not associated with a significantly higher risk of symptomatic intracranial hemorrhage compared with published series for mechanical thrombectomy alone.

Aneurysm of the extracranial carotid artery with spontaneous echo contrast revealed by duplex sonography

A 56-year old male patient without cerebrovascular disease or risk factors presented with a painless, pulsatile right-sided cervical swelling. Ultrasonography showed a large aneurysm of the right common and internal carotid artery with homogeneous thickening of the vessel wall as well as a parietal thrombus and a dilation of the left common and internal carotid artery with markedly reduced blood flow velocities. In the enlarged lumen of the right internal carotid artery spontaneous echo contrast was apparent with slow, ineffective but orthograde blood flow motions. Ensuing diagnostic procedures revealed multiple aneurysms involving the aorta and its branches. Despite surgical removal of the aneurysm and glucocorticoid therapy, the patient died from a ruptured aneurysm of a coronary artery a few weeks later. Post-mortem examination showed panarteritis consistent with Takayasu's disease. Spontaneous echo contrast is a frequent echocardiographic finding in patients with atrial fibrillation and mitral stenosis, indicating decreased blood flow. This is associated with an increased risk of embolism. In our patient, spontaneous echo contrast indicated severely disturbed haemodynamics due to a large aneurysm of the carotid artery. In the rare case of multiple aneurysms, differential diagnosis should include dissections, infections, and connective tissue diseases. Takayasu's arteritis, however, should also be considered, which usually presents with stenoses, but may be associated with multiple aneurysms of the aorta or its branches. If the diagnostic criteria are present, immunosuppressive treatment should be initiated.

[Multiple intracerebral lesions. Identification of the causative agent by 16S rDNA-PCR]

Molecular biological methods such as polymerase chain reaction (PCR) enable microbiologists to detect bacteria even if antibiotic treatment has already been started. Based on this case report of a 39-year-old man with multiple intracerebral lesions, we describe a PCR method called 16S rDNA-PCR which can be used to identify panbacterial DNA by focussing on the universal gene sequences for the bacterial 16S part of the ribosome.