Mohammad Anadani, MD

Kaesmacher J, Mosimann PJ, Giarrusso M, El-Koussy M, Zibold F, Piechowiak E, et al. Multivessel Occlusion in Patients Subjected to Thrombectomy: Prevalence, Associated Factors, and Clinical Implications. Stroke. 2018

Endovascular treatment is the standard of care for patients with acute ischemic stroke secondary to large vessel occlusion. It is not uncommon for patients with large vessel occlusion to present with multivessel occlusion (MVO). In the aforementioned study, the authors aimed to investigate prevalence, associated factors and outcome of MVO.

The authors retrospectively reviewed a prospective registry of patients who presented to comprehensive stroke center between 2012 and 2017 and had angiography with an intention for endovascular treatment. Initial diagnostic workup including CTA and MRA were evaluated by a neuroradiologist to diagnose MVO. A follow-up whole brain digital subtraction angiography (DSA) images were reviewed to confirm MVO.  Downstream MVO was defined as a second occlusion within the territory of and distal to the primary occlusion.

720 patients were included in the study, of whom 77 (10.7%; 95% CI, 6.4%–13.0%) had MVOs present on the initial diagnostic workup. Detection of MVO did not differ between initial diagnostic modality groups (MRA vs. CTA).

16.9% and 2.6% of MVO patients had 3 or 4 occlusions, respectively, and approximately one-third of MVOs (35%) were downstream MVOs. Interestingly, 54.5% of MVOs were not reported in the initial diagnostic study report.

In a multivariable logistic regression analysis, statin treatment (aOR, 0.477; 95% CI, 0.276–0.827), higher admission systolic blood pressure (aOR for 1 mm Hg-increase, 1.014; 95% CI, 1.005–1.023), and primary occlusion site at M2 (aOR, 1.870; 95% CI, 1.103–3.170) were significantly associated with MVOs.

With respect to the outcome, MVO patients had a lower recanalization rate, worse 90-day functional outcome, and higher mortality rate. On multivariate analysis, MVO associated with a lower recanalization rate (aOR, 0.549; 95% CI, 0.316–0.953; P=0.033) and lower rate of good functional outcome (aOR, 0.437; 95% CI, 0.207–0.923; P=0.030; n=537).

This study shed light on the prevalence of MVO and its association with worse outcome. MVOs are commonly overlooked, and it is not surprising that 50% of MVOs were not in the initial diagnostic workup. In light of the results of the aforementioned study, more emphasis should be placed on MVOs in the clinical practice, as well as in research studies.

Despite that MVOs were associated with worse outcome, it is unknown if treating MVO would improve the outcome. Therefore, future prospective studies needed to investigate the best treatment approach for MVO.