Direct Transfer to Angiography Suite Proven as Cost-Effective Choice for LVO

The direct transfer of patients suspected of a large vessel occlusion to the angiography suite may improve the workflow and outcome of endovascular thrombectomy.

Patients suspected of a large vessel occlusion (LVO) who are sent directly to the angiography suite to undergo endovascular thrombectomy (EVT) is a more cost-effective approach than sending patients to the emergency room first, according to study findings published in Neurology

Patients who experience an acute ischemic stroke due to LVO are eligible to undergo EVT. The strategy for the direct transfer of patients suspected of LVO to the angiography suites for treatment has been shown to improve outcomes. Researchers conducted a study to assess the cost-effectiveness of direct transfer to the angiography suite (DTAS) compared with initial transfer to the emergency room (ITER).

The researchers modeled a hypothetical cohort of patients suspected of LVO after the ANGIOCAT randomized control trial conducted in Spain. The ANGIOCAT study assessed functional outcomes 90 days following EVT after DTAS or ITER. The current study generated a cohort of 10,000 patients suspected of LVO with an average age of 74 years. 

Criteria to suspect a patient of LVO was a Rapid Arterial Occlusion Evaluation (RACE) score of greater than 4 and a National Institutes of Health Stroke Scale (NIHSS) score of greater than 10. In the DTAS strategy, patients suspected of LVO would be sent directly to the angiography suite for evaluation. The ITER method sent patients suspected of LVO to the emergency room to confirm LVO and then sent them to the angiography suite if LVO was confirmed. 

[T]he DTAS, combined with prehospital triage for LVO, should be considered a potential strategy to optimize the acute stroke care pathway.

The researchers developed 10-year models to estimate the cost-effectiveness of the DTAS and ITER strategies. Functional outcomes were categorized based on the modified Rankin Scale (mRS) score, with higher scores representing higher disability severity. 

The primary outcome was the incremental cost-effectiveness ratio (ICER), which was calculated as the difference in costs between the 2 methods divided by the difference in quality-adjusted life years (QALYs). The threshold at which DTAS would be considered cost-effective is if the ICER was below $94,616 per QALY. 

When compared with the ITER method, the DTAS method had an additional 0.65 QALYs at an additional cost of $16,089. This resulted in an ICER of $24,925 per QALY, which is below the threshold set by the researchers. The ICER ranged from $27,169 to $38,325 per QALY in different scenarios.

The sensitivity analysis revealed that the DTAS strategy had a 91.8% chance of being cost-effective at a decision threshold per QALY of $59,135. At a decision threshold per QALY of $94,616, there was a 97.0% likelihood of being cost-effective.

“With faster treatment, improved functional outcomes and favorable economic evaluation, the DTAS, combined with prehospital triage for LVO, should be considered a potential strategy to optimize the acute stroke care pathway,” the researchers wrote.

Study limitations included the lack of long-term mRS data, collecting data from a single center, not considering adverse events, and the inability to assess the ICER of introducing these strategies into the health care centers.

References:

Nguyen CP, Lahr MM, van der Zee DJ, et al. Cost-effectiveness of direct transfer to angiography suite of suspected large vessel occlusion patients. Neurology. Published online July 12, 2023. doi:10.1212/WNL.0000000000207583