Purpose: Hemorrhagic complications occasionally occur during mechanical thrombectomy and may lead to catastrophic outcomes. Therefore, remedial strategies require careful investigation. Herein, we aimed to evaluate a cohort of patients who experienced hemorrhage during endovascular procedures, the rescue methods used, and outcomes observed.
Method: This prospective study included patients who had hemorrhagic complications observed on digital subtraction angiography (DSA) during mechanical thrombectomy, between October 2017 and October 2022, at a high-volume stroke center. Functional outcomes were assessed using the modified Rankin scale (mRS) score at a 90-day follow-up. The primary outcomes were favorable outcomes (mRS score: 0-2 points) and mortality rates. The secondary outcomes were rescue therapy success rates, according to extravasation observed on the final DSA, recanalization status, and causes of hemorrhage.
Results: From October 2017 to October 2022, 1537 patients with stroke received emergency endovascular therapy, and 1147 patients completed a 90-day follow-up. Hemorrhage was observed in 33 (2.1%) patients in the process of endovascular interventions. Eighteen (54.5%) cases of hemorrhage were caused by microwire or microcatheter perforation. Mechanical stretching of the vessel during stent retriever withdrawal resulted in 8 (24.2%) cases of hemorrhage. Nine (27.3%) instances of hemorrhage stopped after the reversal of heparin administration and introduction of blood pressure control measures. Further endovascular rescue treatment was performed in 11 patients. Intracranial inflation of the balloon for tamponade stopped 10 hemorrhages, and 1 patient underwent additional coil embolization. Fifteen (45.5%) patients died within 90 days after the procedure. Three (9.1%) patients recovered functional independence (mRS score: 0-2 points) within 90 days.
Conclusion: Hemorrhage during mechanical thrombectomy is a rare but severe complication of acute ischemic stroke with high mortality and disability rates. Intracranial inflation of a balloon for tamponade can effectively stop extravasation.
Clinical impact: This paper described haemorrhagic events characterised by contrast extravasation in the procedure of mechanical thrombectomy due to various causes. Although this complication is rare, patients showed a high mortality and disability rate. There are limited reports available. We found self-limiting haemorrhage had a rather benign prognosis and balloon tamponade could effectively stop the extravasation and might reduce the death rate within 90d. The methods we adopted could be applied in the clinical practice and help neuro-interventionist cope with this complication more promptly and effectively.
Keywords: acute ischemic stroke; balloon tamponade; hemorrhage; mechanical thrombectomy; outcome.