Improvements in Endovascular Treatment for Acute Ischemic Stroke: A Longitudinal Study in the MR CLEAN Registry.

BACKGROUND: We evaluated data from all patients in the Netherlands who underwent endovascular treatment for acute ischemic stroke in the past 3.5 years, to identify nationwide trends in time to treatment and procedural success, and assess their effect on clinical outcomes. METHODS: We included patients with proximal occlusions of the anterior circulation from the second and first cohorts of the MR CLEAN (Multicenter Randomized Clinical trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) Registry (March 2014 to June 2016; June 2016 to November 2017, respectively). We compared workflow times and rates of successful reperfusion (defined as an extended Thrombolysis in Cerebral Infarction score of 2B-3) between cohorts and chronological quartiles (all included patients stratified in chronological quartiles of intervention dates to create equally sized groups over the study period). Multivariable ordinal logistic regression was used to assess differences in the primary outcome (ordinal modified Rankin Scale at 90 days). RESULTS: Baseline characteristics were similar between cohorts (second cohort n=1692, first cohort n=1488) except for higher age, poorer collaterals, and less signs of early ischemia on computed tomography in the second cohort. Time from stroke onset to groin puncture and reperfusion were shorter in the second cohort (median 185 versus 210 minutes; P<0.001 and 236 versus 270 minutes; P<0.001, respectively). Successful reperfusion was achieved more often in the second than in the first cohort (72% versus 66%; P<0.001). Functional outcome significantly improved (adjusted common odds ratio 1.23 [95% CI, 1.07-1.40]). This effect was attenuated by adjustment for time from onset to reperfusion (adjusted common odds ratio, 1.12 [95% CI, 0.98-1.28]) and successful reperfusion (adjusted common odds ratio, 1.13 [95% CI, 0.99-1.30]). Outcomes were consistent in the analysis per chronological quartile. CONCLUSIONS: Clinical outcomes after endovascular treatment for acute ischemic stroke in routine clinical practice have improved over the past years, likely resulting from improved workflow times and higher successful reperfusion rates.

Transsinusoidal portal vein embolization with ethylene vinyl alcohol copolymer (Onyx): a feasibility study in pigs.

PURPOSE: Portal vein embolization is performed to increase the future liver remnant before liver surgery in patients with liver malignancies. This study assesses the feasibility of a transsinusoidal approach for portal vein embolization (PVE) with the ethylene vinyl alcohol copolymer, Onyx. METHODS: Indirect portography through contrast injection in the cranial mesenteric artery was performed in eight healthy pigs. Onyx was slowly injected through a microcatheter from a wedged position in the hepatic vein and advanced through the liver lobules into the portal system. The progression of Onyx was followed under fluoroscopy, and the extent of embolization was monitored by indirect portography. The pigs were euthanized immediately (n = 2), at 7 days (n = 4), or at 21 days postprocedure (n = 2). All pigs underwent necropsy and the ex vivo livers were grossly and histopathologically analyzed. RESULTS: Transsinusoidal PVE was successfully performed in five of eight pigs (63%). In 14 of 21 injections (67%), a segmental portal vein could be filled completely. A mean of 1.6 liver lobes per pig was embolized (range 1-2 lobes). There were no periprocedural adverse events. Focal capsular scarring was visible on the surface of two resected livers, yet the capsules remained intact. Histopathological examination showed no signs of recanalization or abscess formation. Mild inflammatory reaction to Onyx was observed in the perivascular parenchyma. CONCLUSIONS: The porcine portal vein can be embolized through injection of Onyx from a wedged position in the hepatic vein. Possible complications of transsinusoidal PVE and the effect on contralateral hypertrophy need further study.