Neurology Today Conference Reporter: International Stroke Conference

Access daily, concise peer-reviewed reports from the International Stroke Conference selected by the Neurology Today editors.

Tuesday, February 28, 2017

New Coils May Work Better in Intracranial Aneurysms


HOUSTON—A new type of coil that hardens when it contacts liquid might help occlude intracranial aneurysms better than current devices, researchers reported here Thursday at the 2017 International Stroke Conference sponsored by the American Heart Association/American Stroke Association.

Major recurrence occurred among 12 percent of patients receiving the new hydrogel-coated coil compared with 18 percent of patients who received a standard bare-platinum coil, reported Christian Taschner, MD, professor of radiology at the University of Freiburg in Germany.

The investigator-initiated, prospective, randomized open-label trial was conducted in 15 centers in France and seven in Germany. The main endpoints were major aneurysm recurrence at 18 months, retreatment for aneurysm within 18 months, morbidity that prevented angiographic follow-up, and death. From October 2009 to February 2014, the researchers enrolled 513 patients. The researchers randomized 247 patients to receive the hydrogel coil and 253 patients to receive the bare platinum coil.

Dr. Taschner said that in cases of wide-neck aneurysms stents have to be employed to keep the coils from entering the target blood vessel and occluding those conduits. He said about 205 of the patients in each arm of the study had those types of lesions and required stenting.

About 3 percent of patients in the hydrogel arm required retreatment compared with 6 percent of those who had bare-platinum coils; 1 percent of the hydrogel cohort were unfit for angiographic follow-up compared with none of the patients in the bare-platinum coil group. There were seven deaths at 18 months among the hydrogel patients and 10 deaths in the bare-platinum coil cohort.

Overall, 45 patients in the hydrogel group and 66 patients in the bare-platinum group experienced adverse events, Dr. Taschner said in discussing his abstract. Those differences translated into an 8.4 percent reduction in adverse composite primary outcomes with hydrogel, a statistically significant difference (p=0.036).

"Embolization with second-generation hydrogel coils decreases adverse outcomes in endovascular treatment of medium-sized intracranial aneurysms," Dr. Taschner suggested.

Commenting on the study, Mark J. Alberts, MD, chief of neurology at Hartford Hospital in Connecticut, said: "At this point, the device is not used frequently in the United States. Here, most patients are treated with classic coiling or clipping, but I think the hydrogel and other devices are new advances in technology that are very hopeful. The recurrence rate in this study is higher than we would see in studies in the United States. We typically see recurrence rates in single digits."

Dr. Taschner said the figures cited are a composite figure that includes recurrence, retreatment, and adverse events, so the results may not be comparable to other studies.

He also noted that 42 percent of the patients in his study had experienced ruptured aneurysms, often resulting in so-called thunderclap headaches that led to hospitalization and imaging studies that diagnosed the aneurysm.

The study was funded by MicroVention, Inc. in Tustin, CA. The hydrogel coil is approved in Europe and in the United States.​