• Stroke

We would like to thank Dr Hirsch and colleagues from Massachusetts General Hospital for their insightful comment on our paper.1 The authors advocate a more cautious conclusion regarding the efficacy of endovascular stroke intervention in the elderly as a control group of younger patients was lacking in our study. Although comparison with a younger group of patients is interesting, such data can hardly be used for drawing definitive conclusions regarding the efficacy of endovascular therapy. A clinical comparison between young and older patients is unfortunately not possible due to tremendous differences between the two study populations, such as pre-existing medical comorbidities and dementia. Randomized controlled studies comparing patient outcomes with intra-arterial therapy versus intravenous thrombolysis or best medical management will be needed to provide definitive information on the best therapeutic approach in this patient population.

In patients with a National Institutes of Health Stroke Scale score of 8 or above who have failed or were not eligible for intravenous thrombolysis, such as in our study population, medical therapy is unfortunately limited to supportive management. Most of these patients are destined to end of life care or are neurologically devastated from their stroke. In an era of FDA approved intra-arterial thrombolysis, there is an ethical dilemma in randomizing patients that meet criteria to such life saving interventions to medical therapies, regardless of their age group. It is therefore extremely challenging to obtain level 1 evidence data in the elderly or any other age population comparing medical and endovascular stroke therapies.

Timely recanalization in acute ischemic stroke improves patient outcomes.2–4 Arterial recanalization can be achieved by intravenous or intra-arterial means. Evidence suggests that treatment benefit with intravenous tissue plasminogen activator extends to patients older than 80 years.5 It is therefore plausible that intra-arterial thrombolysis could confer a similar benefit in elderly patients. In our study, almost a third of elderly patients achieved favorable outcomes with intra-arterial thrombolysis, and similar rates were also reported by other investigators.6 ,7 In our opinion, such rates can be regarded as satisfactory considering the compromised collateral circulation, the reduced neuronal reserve, as well as the high frequency of pre-stroke comorbid conditions in this age group. However, we agree with Dr Hirsch and colleagues that this would require further confirmation by prospective controlled data.

In a recently published study by Chandra et al 8 from Massachusetts General Hospital, 49 elderly and 130 non-elderly patients treated between 2005 and 2010 were rigorously compared with respect to angiographic reperfusion, rate of parenchymal hematoma, and 90 day clinical outcome. The authors reported comparable rates of reperfusion and hemorrhage between the two groups but favorable outcomes in only 2% of elderly patients, and concluded that recanalization in this group ‘may be futile’. In our view, these results warrant a more cautious conclusion than the one advocated in their report, not only because comparison with a control group treated with medical therapy is lacking but also for the following reasons: (1) nearly 33% of elderly patients in their study were disabled at baseline (modified Rankin Scale score of 2 or greater), which makes the prospect of a favorable outcome nearly impossible in as many as one-third of their cohort; (2) medical care was withdrawn in 55% of elderly patients, which obviously complicates any assessment of outcome; and (3) CT perfusion data were not used to select patients for acute stroke intervention, which could possibly suggest that some patients with little or no salvageable brain tissue may have undergone endovascular treatment. In fact, CT perfusion can optimize patient selection for endovascular recanalization based on an individual's physiological parameters, rather than an arbitrary time frame, and may be of greater value in this specific population by helping identify ‘the subset of elderly patients who may benefit’ from treatment.9–11

Finally, we agree with Dr Hirsch and colleagues that endovascular stroke intervention in elderly patients is safe. Although the question of its efficacy requires more investigation, we believe that elderly patients should not be excluded from consideration for treatment, especially if perfusion studies indicate adequate penumbra. The significance of proper patient selection for endovascular recanalization cannot be overstressed.