The Impact of Endovascular Rescue Therapy on the Clinical and Radiological Outcome After Aneurysmal Subarachnoid Hemorrhage: A Safe and Effective Treatment Option for Hemodynamically Relevant Vasospasm?

Abstract

Objective: Cerebral vasospasm (CVS) represents one of the multiple contributors to delayed cerebral ischemia (DCI) in patients with aneurysmal subarachnoid hemorrhage (aSAH). Especially the management of CVS, refractory to medical treatment, is a challenging task during the acute phase after aSAH. Endovascular rescue therapies (ERT), such as medical and mechanical dilation, are possible treatment options on an individual basis. However, data about the influence on the patients' functional outcomes are limited. This study aims to assess the impact of ERT on the long-term functional outcome in aSAH-patients with refractory CVS.

Methods: We performed a retrospective analysis of aSAH patients treated between 2012 and 2018. CVS was considered refractory, if it persisted despite oral/intravenous nimodipine application and induced hypertension. The decision to perform ETR was made on an individual basis, according to the detection of "tissue at risk" on computed tomography perfusion (CTP) scans and CVS on computed tomography angiography (CTA) or digital subtraction angiography (DSA). The functional outcome was assessed according to the modified Rankin scale (mRS) 3 months after the ictus, whereas an mRS ≤ 2 was considered as a good outcome.

Results: A total of 268 patients were included. Out of these, 205 patients (76.5%) were treated without ERT (group 1) and 63 patients (23.5%) with ERT (group 2). In 20 patients (31.8%) balloon dilatation was performed, in 23 patients (36.5%) intra-arterial nimodipine injection alone, and in 20 patients (31.8%) both procedures were combined. Considering only the patient group with DCI, the patients who were treated with ERT had a significantly better outcome compared to the patients without ERT (Mann-Whitney test, p = 0.02).

Conclusion: Endovascular rescue therapies resulted in a significantly better functional outcome in patients with DCI compared to the patient group treated without ETR. CTP and CTA-based identification of "tissue at risk" might be a reliable tool for patient selection for performing ERT.

Keywords: cerebral vasospasm; endovascular therapy; endovascular treatment; outcome; subarachnoid hemorrhage.

Figure 1

Example of a patient with an indication for ERT with severe vasospasm on the CTA (red arrow, left) with perfusion deficits in the middle cerebral artery territory on the CTP (blue arrow, right).

Figure 2

Timepoint at which ERTs were performed in relation to the timepoint of the bleeding event (the day after aSAH diagnosis).

Figure 3

Conventional angiography showing severe vasospasm of the right internal carotic artery, middle cerebral artery, and anterior cerebral artery before (red arrow, left) and after (blue arrow, right) the intervention.

Figure 4

Comparison of functional outcome of patients with DCI receiving ERT with the patient group with DCI without ERT, showing a significantly higher percentage of patients with good outcome (mRS ≤ 2) in the patient group with DCI and ERT compared to the patient group with DCI without ERT (Fisher's Exact test, p = 0.01).