Thursday, February 14, 2019

Extending Thrombolytic Time Window to 9 Hours for Acute Ischaemic Stroke Is Possible in Select Patients

Once again everything in stroke is a nail when the only tool you have is tPA. And tPA is a failure 88% of the time in getting patients to full recovery.  This wouldn't be quite so bad if there were protocols after tPA adminstration that would get you completely recovered. But there are none, so while you may be alive, there is nothing your doctor can do for you to assure you get even modestly recovered. 

Extending Thrombolytic Time Window to 9 Hours for Acute Ischaemic Stroke Is Possible in Select Patients

By Alex Morrisson
HONOLULU -- February 11, 2019 -- Patients who have experienced an ischaemic stroke who still have salvageable brain tissue identified on imaging may benefit from alteplase as long as 9 hours after the onset of symptoms, according to a study presented here at the 2019 International Stroke Conference (ISC).
In the Extending the Time for Thrombolysis in Emergency Neurological Deficits (EXTEND) study, 37% of patients treated with alteplase in the 9-hour window achieved a modified Rankin score of 0 to 1 at 90 days -- the primary endpoint -- compared with 29% of patients who were treated with placebo (P = .045).
A modified Rankin score of 0 to 2 at 90 days -- a secondary endpoint -- was achieved by 51% of patients treated with alteplase compared with 43% of patients treated with placebo (P = .022).
“EXTEND is the first positive thrombolysis trial in an extended time window using automated penumbral imaging,” said Henry Ma, MD, Monash University, Melbourne, Australia. “The current guideline for thrombolysis in acute ischaemic stroke is less than 4.5 hours from stroke onset. But advanced imaging studies from our group and others suggest that the ischemic penumbra can exist up to 24 hours a after onset, and its salvage can lead to improved outcome.”
In penumbral imaging, an automated algorithm uses computer-assisted tomography scans to determine penumbral mismatch, allowing selection of likely candidates for thrombolysis.
The researchers reported that 25% of patients treated with alteplase achieved early neurological improvement based on an 8-point or better reduction in the National Institutes of Health Stroke Scale (NIHSS) compared with 10% of placebo-treated patients (P = .002).
Of the patients in the alteplase group, 51% achieved 90% reperfusion at 24 hours compared with 28% of patients in the placebo group (P = .001). Of the patients on alteplase, 73% achieved 50% reperfusion at 24 hours compared with 53% of patients on placebo (P = .009).
Of the patients who received alteplase, 70% achieved recanalization at 24 hours compared with 40% of placebo-treated patients (P< .001).
In the study, 113 patients received thrombolysis and 112 patients were assigned to placebo. The patients receiving alteplase were older (mean age, 74 years vs 71.4 years). The median NIHSS score was about 12. Of the patients, 10% were treated in the 4.5- to 6-hour time frame and 25% were treated in the 6- to 9-hour time frame. The median time from onset of symptoms to therapy was 7.2 hours.
Death at 90 days occurred in 9.5% of the placebo-treated patients and in 10% of the alteplase-treated patients (P = .94). Symptomatic intracranial haemorrhage occurred in 1% and 6%, respectively (P = .071).
“There was an increase in the rate of symptomatic intracranial haemorrhage consistent with other thrombolytic trials, but this was not associated with increased mortality and did not negate the positive results of the improved rate of excellent functional outcome,” said Dr. Ma.
Funding for this study was provided in part by Boehringer Ingelheim and iSchemaView.
[Presentation title: Extending the Thrombolytic Time Window to 9 Hours for Acute Ischemic Stroke Using Perfusion Imaging Selection - the Final Result. Abstract LB21]

1 comment:

  1. Salvaging the penumbra may explain why intervention past the 4.5 hour mark improves outcomes.

    ReplyDelete