The primary objectives of the Multi MERCI trial were:
- to evaluate the addition of the Merci L5 Retriever
- additionally permit use of the Merci Retrieval System in the setting of persistent clot following IV t-PA treatment (use in the 0-8 hour window for patients ineligible for IV t-PA was also permitted)
Per the Multi MERCI protocol, up to 230 patients could be treated at up to 30 centers.
The intended trial indication for the Merci L5 Retriever was to restore blood flow in the neurovasculature by removing thrombus in patients experiencing ischemic stroke. Patients that were contraindicated or failed treatment with intravenous t-PA were allowed to be enrolled under the Multi MERCI protocol.
Per the Multi MERCI protocol, following inclusion of the Merci L5 Retriever the operating physician was required to initiate treatment with the Merci L5 Retriever. At the physician's discretion, subsequent passes could be made with the Merci L5 Retriever, Merci X6 Retriever and/or Merci X5 Retriever.
Adverse events were adjudicated by an independent Data Safety and Monitoring Board (Capital DSMB).
- Tissue plasminogen activator (Activase®)Drug
Other Names: Alteplase; tPA Intervention Desc: Thrombolytic
- Mechanical Thrombectomy (Merci Retriever)Device
Other Names: Penumbra system; TREVO; Solitaire Intervention Desc: Extraction of cerebral emboli by using a novel retriever, microcatheter and balloon guide catheter system.
- Merci Retriever Device
Intervention Desc: For patients eligible to participate in the trial, the operating physician initiated treatment with the Merci L5 Retriever to remove large vessel thrombotic occlusion and recanalization of the vessel. Subsequent treatment could be made with Merci X6 or X5 Merci Retrievers. Large vessel arteries are defined as internal carotid, middle cerebral M1/M2 segments, basilar, and vertebral arteries. Recanalization was defined as TIMI II or TIMI III per angiography. ARM 1: Kind: Experimental Label: Treatment Description: Treatment arm patients had at least one Merci Retriever deployed
- Allocation: Non-Randomized
- Masking: Open Label
- Purpose: Treatment
- Endpoint: Safety/Efficacy Study
- Intervention: Single Group Assignment
Following diagnostic cerebral angiography, investigators will use the second generation device (L5) first, up to 6 passes. They may use first generation devices (X5,X6) following L5 as deemed necessary. Following mechanical thrombectomy, investigators may use up to 24 mg if IA t-PA, or 250,000 units IA Urokinase in order to open the target vessel if still closed, or open vessels distal to the treatable vessel. The National Institutes of Health Stroke Scale (NIHSS), Barthel Index, and modified Rankin scores (mRS) are obtained at baseline, 30 and 90 days. CT brain imaging is performed at baseline, immediately post-procedure, 24 hours, and at any time there was a decline in patient neurological status.
|Type||Measure||Time Frame||Safety Issue|
|Primary||Rate of vascular recanalization and the observed rate of procedure-related complications. Recanalization is defined as TIMI grades II and III flow assessed immediately post treatment with the device. Device-related serious adverse events were defined as vascular perforation, intramural arterial dissection, embolization of a previously uninvolved territory, or symptomatic hemorrhage adjudicated as device-related.|
|Secondary||Secondary outcome included the rate of procedure-related serious adverse events, as well as clinical outcomes as measured by the mRS at 90 days, 90-day mortality, and safety dichotomized by use or no use of IV t-PA. Good neurological outcome is defined as mRS ? 2. Procedure-related serious adverse events were defined as vascular perforation, intramural arterial dissection, embolization of a previously uninvolved territory, symptomatic hemorrhage adjudicated as procedure-related, or access site complications requiring surgery or transfusion. Clinically significant procedural complications were defined as a procedure complication with decline in NIHSS of ? 4 or death, or groin complication requiring surgery or blood transfusion.|
|Primary||Revascularization success; Rates of device-related serious adverse events||post-procedure||Yes|
|Secondary||modified Rankin scores||90-day||No|
|Secondary||Symptomatic hemorrhage rate||24 hour post procedure||Yes|