# COmbination of Targeted temperature management and Thrombectomy after acute Ischemic Stroke (COTTIS) to improve favorable neurological outcome: a matched-pair analysis

## TL;DR

This study suggests that combining mild hypothermia with clot removal improves stroke recovery, but more research is needed to confirm the results.

## Contribution

The study presents a novel combination of targeted temperature management and thrombectomy for acute ischemic stroke.

## Key findings

- Hypothermic patients had a 68.2% favorable outcome vs. 29.5% in standard care.
- The odds of a favorable outcome were 5.1 times higher with hypothermia.
- Safety outcomes were similar between the two groups.

## Abstract

Despite the considerable success of endovascular treatment (EVT) in stroke due to large vessel occlusion (LVO), many patients still experience poor outcomes, highlighting the need for additional therapeutic approaches. In a preliminary study [COmbination of Targeted temperature management and Thrombectomy after acute Ischemic Stroke (COTTIS trial)] safety and feasibility of rapid transnasal cooling to 35°C prior to EVT in LVO was established. The objective of this investigation was to determine whether this combination improves outcomes based on a matched-pair analysis of our prospective EVT registry.

A single-center matched-pair analysis was conducted on patients with EVT in LVO. Hypothermic patients were recruited from the prospective COTTIS trial. Normothermic patients were recruited from a prospective stroke registry on EVT in LVO at our institution. Matching parameters were age, gender, National Institutes of Health Stroke Scale (NIHSS), Alberta Stroke Program Early CT Score (ASPECTS), occlusion type/side and Thrombolysis in Cerebral Infarction (TICI) score. Primary outcome was a favorable neurological outcome [modified Rankin Score (mRS) of 0–2] at 90 days.

A total of 66 patients were analyzed (hypothermia: 22; standard care: 44). Temperature profiles differed by a mean of 1°C. A favorable neurological outcome was reached more often in hypothermia (68.2%) compared with standard care (29.5%) [odds ratio 5.1 (95% confidence interval 1.69; 15.38)] (p = 0.004). In the shift analysis in hypothermic patients the probability of attaining a higher score on the mRS was reduced significantly. Safety outcomes did not differ between groups.

Our comparative analysis on periinterventional mild hypothermia in EVT suggests a beneficial effect on clinical outcome. Despite the small sample size the effect size is surprisingly high, which needs critical consideration. Randomized controlled trials are needed to validate these findings.

The COTTIS study was registered at DKRS: DRKS-ID DRKS00023573.

Graphical Abstract