Transvenous Approach for the Treatment of Cerebral Arteriovenous Malformations

Centre hospitalier de l'Université de Montréal (CHUM)77 enrolled

Overview

A new endovascular route for the treatment of brain AVMs may be possible in some cases: Trans-Venous Embolization (TVE). The technique uses microcatheters to navigate to the draining veins of AVM, to reach and then fill the AVM nidus retrogradely with liquid embolic agents until the lesion is occluded. This technique has the potential to improve on some of the problems with the arterial approach to AVM embolization, such as a low overall occlusion rate. However, by occluding the vein first, and filling the lesion with the embolic agent in a retrograde fashion, the method transgresses a widely held dogma in the surgical or endovascular treatment of AVMs: to preserve the draining vein until all afferent vessels have been occluded. Nevertheless, the initial case series have shown promising results, with high occlusion rates, and few technical complications. The method is increasingly used in an increasing number of centers, but there is currently no research protocol to guide the use of this promising but still experimental treatment in a prudent fashion. Care trials can be designed to offer such an experimental treatment, taking into account the best medical interests of patients, in the presence of rapidly evolving indications and techniques.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Arteriovenous Malformations, Cerebral Unruptured Brain Arteriovenous Malformation

Interventions

Standard Trans-Arterial Embolization (TAE)PROCEDURE

The standard TAE, without TVE, is used in patient allocated standard treatment. The arterial approach will consist of at least one attempted catheterization for trans-arterial injection of liquid embolic. If the operator deems, on the table, for a trans-arterial injection to be too dangerous, no arterial injection is necessary. Treatment, where indicated, can be completed through other means.

Trans-Venous Embolization (TVE)PROCEDURE

The experimental treatment is an attempt to completely occlude the AVM using venous catheterization and retrograde EVOH injection during the final session. The trans-venous strategy will consist of at least one transvenous injection of ethyl vinyl alcohol (EVOH), with the choice of delivery microcatheters and other technical details left to the individual operator's discretion.

Eligibility

Sex: ALL

Medical Language ↔ Plain English

Inclusion Criteria: * Any patient harboring a brain AVM (ruptured or unruptured) in whom TVE is considered a promising but yet unproven therapeutic option by the participating clinicians can be submitted to the Case Selection Committee. * Patients must be in stable, non-urgent clinical condition, with the acute phase of the AVM rupture resolved (where applicable). * Case must be approved by the CSC. Notes on potentially suitable cases: 1. Current indications may include (but are NOT restricted to) brain AVMs with a small \<3 cm nidus (or small residual nidus), with a single draining vein, and for which curative treatment can be attained with one or at most two treatment sessions. 2. Physicians are not required to submit cases prior to any or all treatment; a case can be submitted to the CSC for consideration after previous treatments (including previous arterial embolization sessions) have been performed. The timing of the submission of the case will be left to individual operators. Previously treated AVMs (by any other modality: embolization/surgical resection/radiosurgery) are not excluded from TATAM. Exclusion Criteria: * Absolute contra-indication to endovascular treatment or anesthesia. * Inability to obtain informed consent.

Locations (9)

University of Alberta Hospital

Edmonton, Alberta, Canada

Centre Hospitalier de l'Université de Montréal

Montreal, Quebec, Canada

Centre hospitalier universitaire de Bordeaux

Bordeaux, France

Centre hospitalier régional universitaire de Brest

Brest, France

Centre hospitalier universitaire de Grenoble

Grenoble, France

Centre hospitalier universitaire Limoges

Limoges, France

Hôpital Forndation Adolphe de Rothschild

Paris, France

Centre hospitalier universitaire de Rouen Normandie

Rouen, France

Centre hospitalier universitaire de la Réunion

Saint-Paul, France

Outcomes

Primary Outcomes

Angiographic evidence of residual AVM at time of confirmatory catheter angiography.

Angiographic evidence of residual AVM at time of confirmatory catheter angiography

Time frame: 3 months +/- 1 month following embolization

Secondary Outcomes

Failure to safely and effectively position the embolization microcatheter.

Failure to reach a safe and effective microcatheter position for embolization.

Time frame: within day of procedure

Any procedural complication leading to transient new neurological deficit.

Time frame: <5 days

Any procedural complication leading to new neurological deficit.

Time frame: ≥5 days

Any treatment-related complication that prolongs hospitalization by ≥5 days.

Time frame: Within one week

Incidence of new ischemia following treatment (Brain MR imaging prior to discharge with diffusion sequences).

Time frame: within 5 days post procedure

Length of hospitalization (days).

Time frame: ≥5 days

Patient discharge to a location that is not his/her home.

Discharge to location other than home.

Time frame: through to 3 (+/- 1) months follow-up

mRS at discharge and 3(+/-1) months.

Time frame: through to 3 (+/- 1) months follow-up

Incidence of new admission to hospital during follow-up.

Time frame: Within 3 +/- months post final treatment

Incidence of intracranial hemorrhage during follow-up.

Time frame: Within 3 +/- months post final treatment

Incidence of residual AVM on confirmatory catheter angiography at 3(+/-1) months post-treatment.

Time frame: at 3(+/-1) months post-treatment.