Bioactive versus bare platinum coils in the treatment of intracranial aneurysms: the MAPS (Matrix and Platinum Science) trial.
OBJECTIVE
The ability of polymer-modified coils to promote stable aneurysm occlusion after endovascular treatment is not well-documented. Angiographic aneurysm recurrence is widely used as a surrogate for treatment failure, but studies documenting the correlation of angiographic recurrence with clinical failure are limited. This trial compares the effectiveness of Matrix(2) polyglycolic/polylactic acid biopolymer-modified coils with bare metal coils and correlates the angiographic findings with clinical failure (ie, target aneurysm recurrence), a composite end point that includes any incident of posttreatment aneurysm rupture, retreatment, or unexplained death.


METHODS
This was a multicenter randomized noninferiority trial with blinded end point adjudication. We enrolled 626 patients, divided between Matrix(2) and bare metal coil groups. The primary outcome was target aneurysm recurrence at 12 ± 3 months.


RESULTS
At 455 days, at least 1 target aneurysm recurrence event had occurred in 14.6% of patients treated with bare metal coils and 13.3% of Matrix(2) (P = .76, log-rank test) patients; 92.8% of target aneurysm recurrence events were re-interventions for aneurysms that had not bled after treatment, and 5.8% of target aneurysm recurrence events resulted from hemorrhage or rehemorrhage, with or without retreatment. Symptomatic re-intervention occurred in only 4 (0.6%) patients. At 455 days, 95.8% of patients with unruptured aneurysms and 90.4% of those with ruptured aneurysms were independent (mRS ≤ 2). Target aneurysm recurrence was associated with incomplete initial angiographic aneurysm obliteration, presentation with rupture, and a larger aneurysmal dome and neck size.


CONCLUSIONS
Tested Matrix(2) coils were not inferior to bare metal coils. Endovascular coiling of intracranial aneurysms was safe, and the rate of technical success was high. Target aneurysm recurrence is a promising clinical outcome measure that correlates well with established angiographic measurements.
From the Department of Neurosurgery (C.G.M.), Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona neuropub@dignityhealth.org.
C G
CG
McDougall
Clinical and Translational Science Institute (S.C.J.).
S Claiborne
SC
Johnston
Department of Neuroradiology (A.G.), Regional Neurosciences Center, Royal Victoria Infirmary, Newcastle Upon Tyne, UK.
A
A
Gholkar
Departments of Neurological Surgery and Diagnostic Radiology (S.L.B.), Oregon Health and Science University, Portland, Oregon.
S L
SL
Barnwell
Therapeutic Neuroradiology Unit (J.C.V.S.), University General Hospital of Alicante, Alicante, Spain.
J C
JC
Vazquez Suarez
Department of Interventional Neuroradiology (J.M.R.), Hospital Donostia, San Sebastián, Spain.
J
J
Massó Romero
Department of Neurosurgery and Radiology (J.C.C.), Mount Sinai Medical Center, Miami Beach, Florida.
J C
JC
Chaloupka
Service de Neuroradiologie (A.B.), Hôspital Gui de Chauliac, Montpellier Cedex, France.
A
A
Bonafe
Division of Neuroimaging and Intervention (A.K.W.), Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts.
A K
AK
Wakhloo
Department of Diagnostic and Interventional Neuroradiology (D.T.), Montreal Neurological Institute, Montreal, Canada.
D
D
Tampieri
Department of Radiology (C.F.D.), University of California, San Francisco, San Francisco, California.
C F
CF
Dowd
Department of Neuroradiology (A.J.F.), Sunnybrook Health Sciences Center, Toronto, Ontario, Canada.
A J
AJ
Fox
Stryker Corporation (S.J.I., K.C.), Fremont, California.
S J
SJ
Imm
Stryker Corporation (S.J.I., K.C.), Fremont, California.
K
K
Carroll
Departments of Neurointerventional Surgery, Radiology, and Neurosurgery (A.S.T.), Medical University of South Carolina, Charleston, South Carolina.
A S
AS
Turk
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D004621:Embolization, Therapeutic / Q000295:instrumentation* / Q000401:mortality; D019544:Equipment Failure Analysis; D005109:Extracellular Matrix / Q000737:chemistry*; D005260:Female; D006801:Humans; D015994:Incidence; D038622:Internationality; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010984:Platinum / Q000737:chemistry*; D011474:Prosthesis Design; D011859:Radiography; D012008:Recurrence; D012307:Risk Factors; D016037:Single-Blind Method; D015607:Stents / Q000706:statistics & numerical data*; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult
D020099:Coated Materials, Biocompatible; D010984:Platinum