Tomohisa Dembo

Prevalence of Patent Foramen Ovale in the Japanese Population – Autopsy Study –

BACKGROUND Patent foramen ovale (PFO) can cause ischemic stroke because of paradoxical embolism. Autopsy studies have shown that the prevalence of PFO is 25% in whites or blacks. However, there is a paucity of data on the prevalence of PFO in Asians. The aim of this study was to clarify the prevalence of PFO in the Japanese population. METHODSANDRESULTS We reviewed 52,717 autopsy reports, which were collected and edited by the Japanese Society of Pathology from 2009 to 2012. Next, we inspected consecutive 103 formalin-fixed specimens that had already been examined by certified pathologists from 2009 to 2013 to find PFO and atrial septal aneurysm (ASA). ASA was defined as ≥10 mm protrusion of the septum into the left or the right atrium. In the database of the Japanese Society of Pathology, the incidence of PFO was 0.08% (43/52,717). Inspection of heart specimens disclosed that the prevalence of PFO was 13.6% (14/103). None of the PFO cases was reported at the original autopsy. PFO was more frequently found in the subjects with ASA (50%) than in those without ASA (9.7%) (P=0.004). CONCLUSIONS PFO is under-reported in autopsy reports. Re-evaluation of heart specimens disclosed that the prevalence of PFO was 13.6%. The prevalence was lower than reported in the past.

Relationship Between Magnetic Resonance Angiography–Diffusion-weighted Imaging Mismatch and Clinical Outcome in Endovascular Treatment for Acute Ischemic Stroke: Subgroup Analysis of the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism–Japan Registry

BACKGROUND The presence or absence of the penumbra area is important when performing reperfusion therapy in patients with acute ischemic stroke. As a predictor of this penumbra area, magnetic resonance angiography (MRA)-diffusion-weighted imaging (DWI) mismatch is attracting attention. The usefulness of MRA-DWI mismatch (MDM) using the DWI-Alberta Stroke Program Early Computed Tomography Score (ASPECTS) in endovascular treatment (EVT) of patients with cerebral large vessel occlusion was evaluated. METHODS Of 1442 patients registered in the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism-Japan Registry between July 1, 2010 and June 30, 2011 who presented to the hospital within 24 hours of the onset of acute cerebral infarction because of cerebral large vessel occlusion, 188 patients who had internal carotid artery or middle cerebral artery occlusion and achieved recanalization with EVT were included. Of these, 71 patients underwent intracranial EVT because intravenous recombinant tissue plasminogen activator therapy was ineffective. The associations between the presence or absence of MDM (MDM-positive [MDM-P], DWI-ASPECTS≥6; MDM-negative [MDM-N], DWI-ASPECTS<6) and 90-day prognosis (modified Rankin Scale [mRS]) and symptomatic intracranial hemorrhage (sICH) were examined. RESULTS Of the 188 patients analyzed, the time from symptom onset to admission was within 3 hours in 143 patients, 3-8 hours in 36 patients, and 8 hours or more in 9 patients. The time from the onset was within 3 hours in 118 patients in the MDM-P and 25 patients in the MDM-N cases. Favorable outcomes (mRS score≤2 at 90 days) were seen in 63 patients (53.4%) in the MDM-P group and 7 patients (28.0%) in the MDM-N group, showing a significantly more favorable clinical outcome in the MDM-P group (P=.027). The incidence of sICH was significantly lower in the MDM-P group (MDM-P group 3.4%, MDM-P group 20.0%; P=.009). The time from the onset was 3-8 hours in 29 patients in the MDM-P group and in 7 patients in the MDM-N group. Favorable outcomes were seen in 12 patients (41.4%) in the MDM-P group and 2 patients (28.6%) in the MDM-N group, with no significant difference between the 2 groups. No patients had sICH. The patients admitted 8 hours or more after the onset were all MDM-P. Five patients (55.6%) had a favorable outcome. CONCLUSIONS This study demonstrated the safety and efficacy of EVT in MDM-P patients within 3 hours of symptom onset. Although the ratio of patients who had a favorable outcome was high in the MDM-P patients admitted 3-8 hours after the onset, the difference was not significant.

Does Reducing the Duration from Symptom Onset to Recanalization Improve the Results of Intracranial Mechanical Thrombectomy in the Elderly

Endovascular recanalization for acute major cerebral artery occlusion is effective within a short time after symptom onset. However, its efficacy in the elderly remains unknown. We assessed the efficacy of our comprehensive stroke center’s reduction of this time in 28 consecutive patients for elderly patients (defined as patients aged ≥75 years) with acute major cerebral artery occlusion treated with intravenous injection of tissue plasminogen activator, followed by thrombus retrieval by endovascular therapy. The patients were divided into groups according to whether they were treated before implementation of the time reduction measure (from January 2012 to May 2014) or after (from June 2014 to May 2015). The onset-to-door, onset-to-needle, onset-to-recanalization (O2R), door-to-image (D2I), door-to-needle (D2N), door-to-puncture (D2P), door-to-recanalization (D2R), and puncture-to-recanalization time intervals were compared between the two groups. There were 14 patients (including 8 elderly patients ≥80 years) before and 14 patients (including 10 elderly patients ≥80 years) after the time reduction measure. The mean duration of each of the following time intervals was significantly reduced after the time reduction measure (P < 0.05). To reduce the O2R time, the D2P time is the first time interval that can be reduced. At our center, conferences were regularly held to raise awareness among staff and make specific changes in the workflow, and overall time reduction was achieved. Similar results were obtained in elderly patients.

Thrombosis in a Giant Basilar Trunk Fusiform Aneurysm

B ASILAR TRUNK ANEUrysm (also called dolichoectasia)isarelatively rare pathologic condition,andlittleisknown about its natural history and optimal management. Wedescribea66-yearoldwomanwhohadbeenreceivingantihypertensivetreatmentandwhopresentedwithsuddenleftfacialpalsy.Her neurological symptoms deteriorated rapidly in the ambulance on the way to the hospital. Upon admission, she was unconscious and had left facial palsyandsevere rightarmand legparesis. Cranial computed tomography revealedagiant fusiformaneurysmof the basilar artery with a thrombus in thelumen(Figure,A).Brainmagnetic resonance imaging (MRI) revealed slightly restricted diffusion in the left pons with deformation caused by an aneurysm(Figure,B).Magnetic resonanceangiographyshowedindistinct flowofthebasilarartery,probablydue to turbulence and slow flow (Figure, C). We applied basiparallel anatomic scanning(BPAS)–MRItoevaluatethe surface of the vertebrobasilar artery. The technique required 2-cm-thick, heavilyT2-weightedcoronal imaging parallel totheclivus,withgrayscalereversal during postprocessing. The BPAS-MRIconfirmedagiant fusiform aneurysmofthebasilarartery(Figure, D).Thepatientwastreatedwithintravenous sodiumozagrel (a thromboxaneA2synthaseinhibitor)andglycerol solution under strict blood pressure control.However,sheremainedcomatose and required endotracheal intubationtomaintainbreathing.Shedied of respiratory arrest on the day after admission.