Early Treatment, Better Outcomes: Why Mechanical Thrombectomy Timing Matters for Stroke Patients

Credit: Adobe Stock/Gorodenkoff

Delays in door-to-puncture time (DTPT) during off-duty hours significantly worsened outcomes for patients undergoing mechanical thrombectomy for acute ischemic stroke (AIS) within 8 hours of symptom onset, but no such effect was observed for patients treated 8–24 hours post-onset. The findings highlight the importance of reducing time delays in stroke treatment, particularly for patients arriving within 6 hours of symptom onset.

“The impact of off-duty hours mechanical thrombectomy on outcomes remains a subject of controversy,” wrote a group of Korean investigators. “The impacts of off-duty hours on procedures are influenced by various factors, but the most critical one is the time delay in initiating the procedure after the patient’s arrival at the emergency room.”

A recent report indicated the impact of time delay on procedural outcomes is apparent among patients who arrive to the emergency room within 6 hours of symptom onset. Although this can be due to a variety of factors, the most significant reason is delayed treatment initiation because of the absence of specialized medical staff during off-duty hours or weekends.

Therefore, investigators theorized that the effect of delays in DTPT would be more significant during off-duty hours, such as nights and holidays, among patients undergoing mechanical thrombectomy for AIS. Patients who arrived at the emergency center at Dong-A University Hospital in Korea between 2014 and 2022 were included in the analysis. Eligible patients were enrolled prospectively in the Clinical Research Center for Stroke in Korea (CRCS-K) registry, a multicenter prospective, hospital-based stroke database.

Out of 6,496 patients, only those with AIS those who underwent mechanical thrombectomy within the first 24 hours of symptom onset were included in the analysis. The analysis was divided between an "early window" (patients treated within 8 hours of symptom onset) and a "late window" (treated 8–24 hours after onset).

Onset to puncture time in each group and poor outcomes were evaluated at 90 days. The impact of receiving the procedure during off-hours among each cohort on outcomes was also assessed.

Among the 501 patients included in the analysis, 78.8% of patients were placed in the early window category and 63.9% of patients underwent mechanical thrombectomy during the off-duty hours.

Results showed that the probability of a poor outcome at 90 days significantly increased for every 60-minute increase in onset to puncture time (OTPT).

For those in the early window, delays in procedures during off-duty times were considered an independent predictor of worse outcomes. Interestingly, there was no link between DTPT and outcomes at 90 days among patients in the late window, and the impact of delays during off-hours was not seen.

Investigators noted limitations including the relatively small effect of OTDT on the functional prognosis of patients, despite previous studies reporting that OTDT was one of the major prognostic factors. Additionally, the small number of patients with symptomatic intracerebral hemorrhage (SICH) hindered the generalizability of the findings. As the study was performed at a single stroke center, it lacked an adequate number of target patients. Finally, the observational nature of the study made it difficult to precisely divide between the early and late windows.

“We believe that procedural delays during mechanical thrombectomy performed during off-duty hours can impact outcomes,” investigators concluded. “Therefore, there is a need for an effective response within the stroke care system to address this issue.”