Japanese Surveillance of Neuroendovascular Therapy in JR-NET - Part II. Japanese Registry of NeuroEndovascular Treatment 3. Main Report

Abstract

This study, following Japanese Registry of NeuroEndovascular Treatment 1 and 2 (JR-NET 1 & 2), shows an annual trend of cases including adverse events and clinical outcomes at 30 days after NET. JR-NET3 was registered by 749 cumulative total number of physicians, certified by the Japanese Society of Neuroendovascular Therapy in 166 centers, between 2010 and 2014. Medical information about the patients was anonymized and retrospectively registered through a website. A total of 40,177 patients were recruited, 632 patients were excluded because data of preprocedural status were not available. So we analyzed 39,545 patients retrospectively. The proportion of octogenarians is increasing year-by-year and 14.7% in 2014 compared with 10.4% in 2010. Most frequent target disease is intracranial aneurysm. For the proportion of the treatment of intracranial aneurysm, 50.0% in 2010, but that has decreased to 44.8% in 2014. However, number of procedures were increased from 3150 in 2010 to 3419 in 2014. Although before the positive clinical evidence of mechanical thrombectomy for acute ischemic stroke (AIS) was established, the proportion of endovascular treatment for AIS increased 13.8% in 2014 compared with 6.3% in 2010. The number of patients requiring neuroendovascular treatment in Japan is increasing since 2010-2013, but that declined a little in 2014 caused by study operation suspended at the end of 2013. The outcomes of such therapy are clinically acceptable. Details of each type of treatment will be investigated in sub-analyses of the database.

Keywords: clinical outcome; endovascular treatment; nationwide surveillance; registry study; safety endpoint.

Fig. 1.

Annual changes in patients’ age during JR-NET3. Rates of octogenarians increased annually from 10.4% in 2010 to 14.7% in 2014 (P <0.001), whereas the ratio of younger patients (<40 years) remained constant (P = 0.203). JR-NET3: Japanese Registry of Neuroendovascular Therapy 3.

Fig. 2.

Annual changes in the types of procedures. The proportion of treatments remained relatively constant, but acute stroke significantly increased from 5.9% in 2010 to 12.7% in 2014 (P <0.001).

Fig. 3.

Number of elective and emergency procedures. The total numbers of elective and emergency procedures increased annually except for 2014, and emergency procedure significantly increased from 31.9% in 2010 to 35.6% in 2014 (P <0.001).

Fig. 4.

Proportions of Modified Rankin Scale (mRS) scores before and after procedures. Ratio of patients with mRS 0–2 was ≥90% before therapeutic procedures (A), decreased at 30 days thereafter (B), but remained >75%.

Fig. 5.

Proportions of Modified Rankin Scale (mRS) scores at 30 days after various procedures. Outcomes were favorable (mRS 0–2) for 58.3% and 95.3% of patients with ruptured and unruptured aneurysms respectively. Ratios of favorable outcomes of carotid artery stenting, vertebral artery/subclavian artery, dural arteriovenous fistula, and tumor embolization were >85%. On the other hand, the ratios of favorable outcomes were 75.5%, 71.6%, and only 33.1% in intracranial artery disease, arteriovenous malformation and acute stroke, respectively.

Fig. 6.

Complications associated with each procedure. Death and major complication rates were higher after procedures for ruptured aneurysm (5.1%) and acute stroke (5.23%), but less frequent for those that treated dural arteriovenous fistula (0.46%), tumor embolization (0.46%), and vertebral artery/subclavian artery (0.82%).