In the past, stroke treatment mainly involved intravenous tissue-type plasminogen activator (IV-tPA) treatment and managing stroke complications (such as emergency craniotomy). Approximately 20 ~ 30% of ischemic stroke patients suffer from large vessel occlusion (LVO). However, recanalization rate is only about 20% for these patients even with IV-tPA treatment. Furthermore, IV-tPA treatment has a narrow treatment window and more than 40 contraindications. When LVO is followed by cerebral edema or cerebral hemorrhage combined with compression of the brain stem, the mortality rate is 80%. For such cases, the mortality rate can be lowered to 20% if an emergency craniectomy is performed; however, the functional prognosis remains poor, and as such, the treatment of ischemic stroke has become a bottleneck in medical treatment. To tackle this problem, the authority in stroke treatment in Taiwan, Superintendent Der–Yang Cho of China Medical University Hospital (CMUH), along with Director General Chon-Haw Tsai of the Department of Neurology and Director Pao-Sheng Yen of the Department of Neuroradiology, assembled an interdisciplinary team and introduced the latest techniques in stroke treatment with the highest efficiency to revert ischemic brain tissue at risk.
Intra-arterial Thrombectomy + Latest Equipment + Optimized Procedures = High Recanalization Rate
Improving Recanalization Rate: Turning the Tide against Ischemic Stroke. The China Medical University Stroke Center has had an excellent treatment plan for strokes using thrombolytic agents and is the country's benchmark hospital with the highest number and proportion of thrombolysis cases. In 2014, the Stroke Center successfully introduced the intra-arterial thrombectomy technique and has significantly improved recanalization rate by using the latest thrombectomy instrument and optimizing the protocol. The latest thrombectomy instruments allow the operator to see the opening of the stent and mediate thrombus aspiration with a intermediate catheter to improve recanalization rate on the first attempt. The latest guidelines for stroke treatment now include intra-arterial thrombectomy for anterior circulation stroke within 8 hours and posterior circulation stroke within 24 hours. The common concern about whether intra-arterial thrombectomy is suitable immediately after treatment with a thrombolytic agent has been dispelled by CMUH. After numerous cases and medical journal publications, CMUH reached the conclusion that the two types of treatment can be given in sequence without having to wait for the effectiveness of the thrombolysis. This indirectly grants more treatment time and shortens the period for which the brain cells is without blood and oxygen, thereby turning the tide against stroke.
Aside from possessing outstanding medical expertise, the emergency protocol is also a key component of stroke management. CMUH emphasizes "rescuing brain cells by swiftly recanalizing the large vessels," so the rescue protocol is activated the moment an acute stroke patient enters the emergency room.
Optimizing the Stroke Registry and Leading the Stroke Defense in Central Taiwan
CMUH and international journals have all proved that thrombectomy combined with general anesthesia can greatly improve treatment outcome and safety. As a result, the team has joined forces with the Department of Anesthesia to stay on call 24 hours a day, ready to perform the intraarterial thrombectomy within 30 minutes according to emergency operation protocol. By speeding up the involvement of the anesthesiologist, the puncture time is shortened, the treatment flow is improved, and the risk of pneumonia and complications of intra-arterial thrombectomy are reduced. With the seamless transition of treatment, optimized acute stroke protocol initiation, interdisciplinary coordination, and regional collaboration, the proportion of patients living independently 3 months after the event have gradually increased. The percentage of cases with a score of 0-2 on the modified Rankin Scale (mRS) has reached 39.2%, possibly the highest among institutions in Taiwan. The excellent recanalization rate at CMUH has even surpassed that of the Netherlands (mean = 59%) and Spain (mean = 66%), well deserving of the "world-class" designation.
CMUH will continue to take the lead as the defender against strokes in Central Taiwan. It has already begun actively coordinating the sharing of resources between institutions for stroke treatment. As institutions and doctors with the ability to treat cerebrovascular conditions are extremely rare and strokes must be treated within a small time window, the integration of medical information can shorten the time of treatment and prevent high-risk transfers. As such, while the Center manages the world's second largest stroke registry, it also feeds back treatment information to other medical institutions to track patient history, monitor patient status, and mitigate the chance of a second stroke for individual cases. It even collaborates with the stroke management system to improve rehabilitation and prognosis. In the future, CMUH aims to expand onto the global stage and establish a medical training facility for strokes for the Asia-Pacific to provide training for stroke treatment techniques and recommendations for protocols. In addition, it will prioritize training thrombectomy personnel to solve the complex stroke problem that is highly prevalent among Asians.
(Editing by Nicole Yang, Research Center for Biotechnology and Medicine Policy)