Complications of endovascular treatment of cerebral aneurysms

Safety and efficacy of adjunctive balloon remodeling during endovascular treatment of intracranial aneurysms: a literature review

BACKGROUND AND PURPOSE

Concurrent temporary inflation of a nondetachable balloon in the parent artery has been reported to be useful during endovascular coiling of complex, wide-neck aneurysms, facilitating truer coil reconstruction of the native vessel. Nevertheless, there exists concern that adjunctive use of balloon assistance may lead to increased adverse events during aneurysm coiling.

MATERIALS AND METHODS

A literature search of all of the unassisted and balloon-remodeling studies published between 1997 and 2006 was conducted with application of strict selection criteria based on the reporting of complication incidence and outcome. The final cohort was analyzed to determine rates and clinical outcomes of iatrogenic aneurysm rupture and thromboembolism. Additional data were collected on the degree of initial and follow-up aneurysm occlusion rates.

RESULTS

A total of 83 potential studies (4973 patients) were identified, from which 23 articles reporting results for 867 traditional-unassisted and 273 balloon-assisted coiled aneurysms met inclusion criteria for the analysis of thromboembolic complications, and 21 articles with 993 routinely coiled and 170 balloon-remodeled aneurysms were eligible for iatrogenic perforation analysis. No statistically significant difference was found in the rates of thromboembolism. Iatrogenic perforation rates were also comparable, though the overall numbers were too few for meaningful statistical analysis. Both initial and follow-up aneurysm occlusion rates were higher in balloon-assisted cases.

CONCLUSION

This largest-to-date literature review and meta-analysis did not demonstrate a higher incidence of thromboembolic events or iatrogenic rupture with the use of adjunctive balloon remodeling compared with unassisted coiling. Balloon remodeling appears to result in higher initial and follow-up aneurysm occlusion rates.

Coil Knotting during Endovascular Coil Embolization for Ruptured MCA Aneurysm. A Case Report

SUMMARY

Complications during coil embolization of cerebral aneurysms include thromboembolic events, hemorrhagic complications related to procedural aneurysmal rupture and parent vessel perforation, and coil-related complications. The present report describes a rare coil-related complication involving spontaneous coil knotting.

Anatomic results and complications of stent-assisted coil embolization of intracranial aneurysms

SUMMARY

The purpose of this study was to evaluate and report our anatomic results and complications associated with stent-assisted coil embolization of intracranial aneurysms using the Neuroform stent. From September 2003 to August 2007, 127 consecutive patients (ruptured 50, 39.4%; unruptured 77, 60.6%) underwent 129 stent-assisted coil embolization procedures to treat 136 aneurysms at our institution. Anatomic results at follow-up, procedure-related complications, and morbidity/mortality were retrospectively reviewed. Stent deployment was successful in 128 out of 129 procedures (99.2%). Forty-seven patients presented with 53 procedure-related complications (37.0%, 47/127). Thromboembolic events (n=17, 13.4%) were the most common complications, followed by intraoperative rupture (n=8, 6.3%), coil herniation (n=5, 3.9%), and postoperative rupture (n=4, 3.1%). For thromboembolic events, acute intra-procedural instent thromboses were observed in two patients and subacute or delayed in-stent thromboses in three patients. Overall mortality rate was 16.5% (21/127) and procedure-related morbidity and mortality rates were 5.5% (7/127) and 8.7% (11/127) retrospectively. Patients with poor grade subarachnoid hemorrhage (Hunt and Hess grade IV or V; 25/127, 19.7%) exhibited 56% (14/25) overall mortality rate and 24% (6/25) procedure-related mortality rate. Immediate angiographic results showed complete occlusion in 31.7% of aneurysms, near-complete occlusion in 45.5%, and partial occlusion in 22.8%. Sixty nine patients in 70 procedures with 77 aneurysms underwent angiographic followup at six months or later. Mean follow-up period was 13.7 months (6 to 45 months). Complete occlusion was observed in 57 aneurysms (74.0%) and significant in-stent stenosis was not found. Thromboembolism and intra/postoperative aneurysm ruptures were the most common complications and the main causes of procedure-related morbidity and mortality. Patients with poor grade subarachnoid hemorrhage showed poor clinical outcomes. Since most complications were induced by stent manipulation and deployment, it is mandatory to utilize these devices selectively and cautiously. While the follow- up angiographic results are promising, further studies are essential to evaluate safety, efficacy, and durability of the Neuroform stent.

Complications of Neuroform stent in endovascular treatment of intracranial aneurysms

BACKGROUND

The Neuroform stent can help in the treatment of difficult, wide-necked intracranial aneurysms. The objective of our study is to report some of the challenges associated with the Neuroform stent in the treatment of intracranial aneurysms.

METHODS

From January 2003 to August 2006, consecutive patients treated with Neuroform stent for intracranial aneurysms were prospectively enrolled. Information on patient demographics, cerebrovascular risk factors, aneurysm size and location were collected. Technical and clinical complications as well as clinical outcomes were measured. Data were analyzed retrospectively using SPSS software version 11.5.

RESULTS

Successful deployment of the stent, in the target artery, was achieved in 65/67 (97%) patients. Stent deployment failed in two cases and the migration of stent developed in one during coiling. Postoperative thromboembolic events developed in three patients. These three patients possessed hyperactive platelets, and were treated with intravenous eptifibatide. Intraoperative rupture of aneurysm developed in one patient, which was secured by subsequent coiling. Majority of the patients had good outcomes GOS (Glasgow Outcome Score) 1 or NIHSS (National Institute of Health Stroke Scale) 0 in 63/67 (94%), GOS 2 or NIHSS 2 in one patient and GOS 3 or NIHSS 4 was observed in three cases.

CONCLUSION

Despite a low rate of intraoperative complications, post-procedural thromboembolic events were common in Neuroform stent-treated patients, which might be associated with hyperactive platelets. Further studies are warranted to identify any potential relationship between post-stent hyperactive platelets and thromboembolism.

Endovascular therapy of distal anterior cerebral artery aneurysms-an effective treatment option

BACKGROUND

Surgical treatment of APAs is associated with relatively high morbidity and mortality. The aim of this study was to illustrate the technical achievements of endovascular procedures in the distal anterior cerebral artery area, technical difficulties and how they can be overcome, and the outcome of endovascular treatment of APAs.

METHODS

Between 1997 and 2006, of 49 patients with APAs at our institution, 29 were treated endovascularly (4.1% of all endovascularly treated aneurysms; F:M = 3.8; mean age, 52.8 +/- 11.5 years), and 12 were treated surgically. Twenty-one (72.4%) of the endovascularly treated patients had a subarachnoid hemorrhage. The mean observation period was 25 +/- 22.8 months.

RESULTS

In 27 (93.1%) cases, complete occlusion of the aneurysm was achieved. The intervention led to 5 (17.2%) cases of minor complications with no neurologic deficits: 2 thromboembolisms, 1 local thrombus, 1 occlusion, and 1 recurrent hemorrhage. Mortality related to the intervention was 3.4%. There was no morbidity associated with the elective procedures. The dome-to-neck ratio is the main predictor of reperfusion. The most important factor impairing the outcome in terms of the GOS status is the presence of an intraparenchymal hematoma, followed by thrombembolic complications.

CONCLUSION

Endovascular treatment of APAs is feasible, safe, and effective. Mortality and morbidity are comparable with surgical therapy. An intraparenchymal hematoma has a severe negative influence on the patient's condition after rehabilitation. In these cases, surgical intervention should be considered. In case of incomplete occlusion of the aneurysm, prompt reintervention is required.

HydroCoil Endovascular Aneurysm Occlusion and Packing Study (HELPS trial): procedural safety and operator-assessed efficacy results

BACKGROUND AND PURPOSE

Coated coils have been in clinical use for several years without robust evidence to determine their safety/efficacy. The HydroCoil Endovascular Aneurysm Occlusion and Packing Study (HELPS) addresses this deficiency for the HydroCoil embolic system. This article reports periprocedural safety/operator-assessed angiographic results from HELPS.

MATERIALS AND METHODS

Patients were randomized to the hydrogel coil or control arms by using concealed allocation with minimization matching groups. Any bare platinum coils were allowed in the control arm, and assist devices could be used as clinically required. Both recently ruptured and not recently ruptured/unruptured aneurysms were included. Analysis was on an intention-to-treat basis.

RESULTS

Four hundred ninety-nine patients were recruited. Coiling was successful in 98.6%. Mean aneurysm size was 6.5 mm (26% were > or =10 mm), 53% were recently ruptured aneurysms, and an assist device was used in 46%. Seventy procedural adverse events were reported in hydrogel coils and 86 in control arms. The 3-month mortality rate was 3.6% in hydrogel coils and 2.0% in control arms; the difference was not significant (P = .6). There was a lower 2-month mortality rate in the HELPS subarachnoid hemorrhage cohort (4.1%) than would be anticipated from the International Subarachnoid Aneurysm Trial (7%). There was a trend toward increased adverse events when assist devices were used, which was substantial for stents deployed in recently ruptured aneurysms. Ninety-six percent of patients discharged were World Federation of Neurosurgeons grade 0-2 at discharge. No difference was found between arms in the operator assessment of angiographic occlusions (P = .3).

CONCLUSION

These HELPS results reinforce coiling as an effective treatment for aneurysms, with an excellent technical success rate. Hydrogel coils can be used in a wide spectrum of aneurysms with a risk profile equivalent to that of bare platinum.

Rebleeding after endovascular embolization of ruptured cerebral aneurysms

This study retrospectively reviewed 227 patients with ruptured solitary cerebral aneurysm who underwent endovascular embolization with detachable coils between March 1997 and March 2006 to establish the incidence of rebleeding after endovascular treatment for ruptured cerebral aneurysm and identify the risk factors. The site and size of the aneurysm, the interval between treatment and rebleeding, and the outcome were investigated in six of the 227 patients (2.6%) who rebled after treatment. Four patients had large or giant aneurysms located on the internal carotid artery at the origin of the posterior communicating artery. The interval between treatment and rebleeding was less than 1 year in four patients (mean 394.2 days). Two patients died, and the survivors had modified Rankin Scale scores of 0, 2, 3, and 4. Re-embolization was performed in four patients and no further bleeding occurred during the mean follow-up period of 1.9 years after re-treatment. Patients with giant aneurysms of the internal carotid artery are at increased risk for rebleeding. Re-treatment should be considered if there is conventional and/or magnetic resonance angiographic evidence of dome filling. Patients with ruptured cerebral aneurysms must be followed up with diagnostic imaging closely during the first 12 months post-embolization because rebleeding frequently occurs within 1 year after initial treatment. Re-embolization is safe and effective in patients with recurrent hemorrhage from aneurysms previously embolized with detachable coils.

Magnetically-assisted remote control (MARC) steering of endovascular catheters for interventional MRI: a model for deflection and design implications

Current applied to wire coils wound at the tip of an endovascular catheter can be used to remotely steer a catheter under magnetic resonance imaging guidance. In this study, we derive and validate an equation that characterizes the relationship between deflection and a number of physical factors: theta/sin(gamma-theta) = nIABL/EI(A) where theta is the deflection angle, n is the number of solenoidal turns, I is the current, A is the cross-sectional area of the catheter tip, B is the magnetic resonance (MR) scanner main magnetic field, L is the unconstrained catheter length, E is Young's Modulus for the catheter material, and I(A) is the area moment of inertia, and y is the initial angle between the catheter tip and B. Solenoids of 50, 100, or 150 turns were wound on 1.8 F and 5 F catheters. Varying currents were applied remotely using a DC power supply in the MRI control room. The distal catheter tip was suspended within a phantom at varying lengths. Images were obtained with a 1.5 T or a 3 T MR scanner using "real-time" MR pulse sequences. Deflection angles were measured on acquired images. Catheter bending stiffess was determined using a tensile testing apparatus and a stereomicroscope. Predicted relationships between deflection and various physical factors were observed (R2 = 0.98-0.99). The derived equation provides a framework for modeling of the behavior of the specialized catheter tip. Each physical factor studied has implications for catheter design and device implementation.

Balloon-assisted coiling of intracranial aneurysms: evaluation of local thrombus formation and symptomatic thromboembolic complications

BACKGROUND AND PURPOSE

Remodeling balloons are used to assist in endovascular coiling of aneurysms. We evaluated our experience with balloon-assisted coiling (BAC) in an attempt to determine whether this technique increased the rate of thrombus formation or symptomatic thromboembolic complications.

MATERIALS AND METHODS

In 3 years, we treated 221 patients with intracranial aneurysms. Statistical analysis was performed to assess whether BAC increased the rate of thrombus formation or symptomatic thromboembolic complications. Patient demographics, aneurysm size, location, neck width, antiplatelet therapy, and rupture status were evaluated.

RESULTS

We detected no statistically significant difference in rates of thrombus formation (14% versus 9% with and without BAC, respectively, P=0.35) or symptomatic thromboembolic events (7% versus 5% with and without BAC, respectively, P=0.76), though our power to detect small differences was limited. There was also no correlation with age, sex, rupture status, aneurysm size, or location. There was a significant increase in the rates of thrombus formation (6% versus 16%, P=0.02) and symptomatic thromboembolic complications (3% versus 10%, P=0.04) in aneurysms that were classified as narrow- or wide-necked, respectively. The use of clopidogrel was associated with a decrease in the rate of complications (P=0.01).

CONCLUSION

In this series, we detected no significant increase in the rates of either intraprocedural thrombus formation or symptomatic thromboembolic events in patients treated with BAC. Larger studies are required to confirm our observations. Wide-necked aneurysms were independently associated with increased rates of thrombus formation and symptomatic thromboembolic complications, whereas the use of clopidogrel was protective (P=0.01).

Ruptured cerebral aneurysm complicated with rebleeding following thrombolysis during endovascular embolization: two case reports

A 68-year-old woman and a 42-year-old woman presented with subarachnoid hemorrhage due to rupture of cerebral aneurysm. Both patients were treated with endovascular coil embolization. Thromboembolic complications occurred during the procedure and local thrombolysis was performed for recanalization. One patient developed massive rebleeding immediately after the procedure and the other suffered minor hemorrhage adjacent to the embolized aneurysm 2 days later. Local thrombolysis during treatment of ruptured aneurysm by coil embolization carries a significant risk of rebleeding. Prevention of thromboembolic complication by adequate heparinization is important.

Hémorragie sous-arachnoïdienne par rupture d'anévrisme et déficit en facteur VII, à propos d'un cas

The management of subarachnoid haemorrhage by aneurysm rupture is well codified. Some rare cases can be problematical. We report a case of a patient suffering from factor VII (FVII) deficiency who presented a subarachnoid haemorrhage by sylvian aneurysm rupture. The bleeding risk was prevented by plasmatic factor VII substitution and aneurysm coiling. Anticoagulation in order to prevent from thromboembolic risk after embolisation was started for 36 hours, associated with plasmatic FVII substitution (with an objective of plasmatic FVII rate of 30%). After this stage at high thromboembolic risk, there has been no shift to platelet antiaggregants and FVII substitution was stopped. The outcome at 1 month was propitious without any bleeding nor arterial thrombosis.

Preliminary evaluation of the endovascular treatment of intracranial aneurysms with detachable coils in vigil patients

Endovascular treatment of intracranial aneurysms with coil embolization became the most important therapeutic option with better morbidity and mortality rates and quality of life. Following immobility, patients are treated with general anaesthesia.

OBJECTIVE

To test viability of endovascular treatment on wake patients.

METHOD

Considering clinical symptoms, psychological characteristics and aneurysmal morphology, four patients with five intracranial aneurysms were selected.

RESULTS

Four among five cases were completed with this technique. Patient 1 was partially treated after 75 minutes presenting vesical stress. Patient 2 presented subarachnoid hemorrhage after aneurysmal re-rupture, and the procedure was completed under general anaesthesia. The other three patients presented no intercurrences during the treatment.

CONCLUSION

Endovascular treatment on wake patients with intracranial aneurysm can be an alternative to a selected group of patients.

Endovascular embolization vs surgical clipping in treatment of cerebral aneurysms: morbidity and mortality with short-term outcome

BACKGROUND

Endovascular embolization of cerebral aneurysms has evolved rapidly worldwide within the last years, and has gained more popularity at the expense of surgical clipping; however, both regimens have inherent risks. This study was undertaken to asses the cerebral complications associated with both modalities of cerebral aneurysm treatment.

METHODS

We retrospectively reviewed the charts, operative and embolization reports, and imaging of patients who underwent surgical clipping or embolization for cerebral aneurysms at our institution between October 2001 and October 2004. Patients were divided into 2 groups: group A, patients who had confirmed subarachnoid hemorrhage; group B, patients with unruptured cerebral aneurysms. Patients belonging to group A were evaluated according to the Hunt and Hess scale with their computed tomography scan evaluated according to Fisher scale. Short-term outcome was measured with Glasgow Outcome Scale for both groups.

RESULTS

One hundred thirty-three patients with 168 aneurysms were treated; 95 (71.4%) were women and 38 (28.6%) men; mean age was 60.28 years. Hypertension (29.6%) was the most commonly encountered risk factor; average size of aneurysms treated was 7.21 mm; 53 patients belonged to group A. Seven patients were Hunt and Hess grade I, 23 grade II, 11 grade III, 7 grade IV, and 5 grade V. Eighty patients belonged to group B; for both groups, the periprocedural technical complication rate associated with coiling was 8.4% vs 19.35% with clipping. Follow-up angiographic results were better with clipping, as total aneurysm occlusion was 81.4% vs 57.5% with coiling. In group A, the incidence of angiographic vasospasm was 17.4% vs 45.4% with coiling vs clipping, whereas the incidence of shunt-dependant hydrocephalus was comparable with embolization and clipping. In group A, excellent outcome was achieved in 62% vs 44% (endovascular vs surgical) of subgroups, whereas in group B, it was 93% vs 81%, respectively.

CONCLUSION

With rapidly evolving technology of endovascular embolization, accumulated experience, and good selection of patients with optimum angioanatomical criteria and endovascular accessibility, our results of morbidity and mortality associated with both modalities of cerebral aneurysm treatment with short-term outcome show that endovascular embolization of cerebral aneurysms is a safe alternative to surgical clipping in the treatment of both ruptured and unruptured cerebral aneurysms; however, long-term outcome needs to be evaluated.

Silent cerebral ischaemia: hidden fingerprints of invasive medical procedures

Cardiovascular and cerebrovascular disorders are the main cause of death and permanent disability worldwide. Improved diagnostic and therapeutic options for these diseases have led to increasing numbers of invasive procedures such as angiography, stent placement, and operations exceeding 4 million each year in the USA. Although clinical examinations suggest a relatively low risk for ischaemic complications affecting the brain, new magnetic resonance techniques have led to the awareness of much higher numbers of clinically silent ischaemic brain lesions. Diffusion-weighted MRI (DWI) has shown new ischaemic lesions in a substantial number of patients undergoing cardiac or carotid-artery surgery, and coronary or cerebral-angiographic interventions. The clinical impact of these "silent" ischaemic lesions within brain areas without primary motor, sensory, or linguistic function ("non-eloquent" brain areas) is debated. There is increasing evidence, however, that cumulative burden of ischaemic brain injury causes neuropsychological deficits or aggravates vascular dementia. Thus, DWI emerges as a valuable diagnostic method for the monitoring of periprocedural ischaemic events in the brain, and could be a surrogate parameter for optimising diagnostic and therapeutic vascular procedures in the future.

Stent-assisted detachable coil embolization of pseudoaneurysms in the coronary circulation

Pseudoaneurysms in the coronary circulation are an uncommon occurrence that can develop spontaneously in the setting of atherosclerosis or can develop after catheter-based coronary interventions. The natural history, clinical outcome, and optimal therapy for pseudoaneurysms in the coronary circulation are not clearly established. Recent advances in the techniques and technologies used for endovascular treatment of intracranial aneurysms may be applicable to the management of coronary aneurysms and pseudoaneurysms. We present a case of spontaneous coronary pseudoaneurysm formation after paclitaxel drug-eluting stent implantation and a case of pseudoaneurysm formation in a saphenous vein graft that were both successfully treated with stent-assisted detachable coil embolization.