Washington, DC - Thrombolytic therapy can safely reduce the impact of ischemic stroke developing after cardiac catheterization procedures, conclude researchers, who say their retrospective analysis is the first of its kind to systematically look at the strategy in an unselected population [1].

That gives their findings some weight, according to the group, led by Dr Pooja Khatri (University of Cincinnati, OH), who nevertheless recommends that the strategy be further explored in large, prospective registries.

The analysis from Khatri et al appears in the March 4, 2008 issue of the Journal of the American College of Cardiology. Its 66 stroke cases, of which 12 (18%) were managed with thrombolytics, represented all documented strokes developing within 36 hours of diagnostic, interventional, or electrophysiologic cardiac cath procedures at seven academic medical centers with acute stroke teams that had been invited to participate.

Thrombolytic therapy had consisted of the tissue plasminogen activator (tPA) alteplase (Activase, Genentech), given IV in seven and intra-arterially in five cases. Over 24 hours, the 12 lytic-treated patients showed a median 6-point improvement in the National Institutes of Health Stroke Scale (NIHSS), a validated gauge of neurologic stroke outcomes. That compared with no overall change in NIHSS score at 24 hours among patients who didn't get thrombolytics (p<0.001).

"These data reassure us that it makes sense to set up a code stroke protocol in every cath lab: time is brain, so the inevitable complication should be planned for," writes Dr Patrick D Lyden (University of California, San Diego) in an accompanying editorial [2].

These data reassure us that it makes sense to set up a code stroke protocol in every cath lab: time is brain, so the inevitable complication should be planned for.

The observed clinical benefits of thrombolytic therapy were independent of stroke severity, he notes. "Thus, the idea of waiting and observing a stroke related to cardiac catheterization is just as inadvisable as it is in other situations."

Both Lyden and Khatri et al observe that thrombolytics have been less well-studied in the post-cardiac-cath setting than typical out-of-hospital ischemic stroke: the post-cath complication is comparatively rare, and there are concerns about bleeding after an invasive procedure that is accompanied by antithrombotic therapy.

But no symptomatic cases of intracranial hemorrhage (ICH) were seen in current analysis, as compared with rates of 6.4% and 10% in clinical trials of IV and intra-arterial thrombolytic stroke therapy, respectively, according to Khatri et al. Nor, in the current study, did lytic therapy up the risk of puncture-site bleeding or other bleeding complications—except the rate of asymptomatic CT-defined ICH was elevated in the lytic group (25%, vs 6% among post-cath stroke patients who didn't get thrombolytics, p=0.037).

Still, Khatri told heartwire, tPA would be contraindicated in post-cath patients who had recently been given abciximab or anticoagulants, although treatment with aspirin or a thienopyridine would be okay.

She said that stroke severity was the only baseline feature that seemed to influence whether patients received tPA; not surprisingly, those with milder strokes were much less likely to. So a secondary analysis was conducted after patients with the mildest strokes were excluded; tPA recipients still fared significantly better (p=0.008).

The study didn't shed light on whether IV or intra-arterial thrombolytic may be best in this setting. Lyden writes that "the call should be left to the consulting stroke team; it makes sense to go with whatever procedure is most typical in the facility."