Preexisting Cerebral Microbleeds on Susceptibility-Weighted Magnetic Resonance Imaging and Post-Thrombolysis Bleeding Risk in 392 Patients

If we are worried about bleeding post tPA administration, maybe the answer should be to use less tPA because we have set it up to be directed to the clot via magnetic nanoparticles. Thus needing to use less quantity. Doesn't anyone think at all?
The ASA blog response here: Nothing on solutions to the problem.
Cerebral microbleeds and thrombolysis for acute stroke: should we be concerned?

The abstract here:

https://stroke.ahajournals.org/content/early/2014/04/17/STROKEAHA.114.004796.abstract

1. Pascal P. Gratz, MD*,
2. Marwan El-Koussy, MD*,
3. Kety Hsieh, MD,
4. Sebastian von Arx, MD,
5. Marie-Luise Mono, MD,
6. Mirjam Rachel Heldner, MD,
7. Urs Fischer, MD,
8. Heinrich P. Mattle, MD,
9. Christoph Zubler, MD,
10. Gerhard Schroth, MD,
11. Jan Gralla, MD,
12. Marcel Arnold, MD* and
13. Simon Jung, MD*

+ Author Affiliations

1. From the Department of Diagnostic and Interventional Neuroradiology (P.P.G., M.E.-K., K.H., C.Z., G.S., J.G., S.J.) and Department of Neurology (S.v.A., M.-L.M., M.R.H., U.F., H.P.M., M.A., S.J.), Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland.

1. Correspondence to Heinrich P. Mattle, MD, Department of Neurology, Inselspital, University Hospital Bern, University of Bern, Freiburgstrasse 10, 3010 Bern, Switzerland. E-mail heinrich.mattle@insel.ch

1. ↵* Drs Gratz, El-Koussy, Arnold, and Jung contributed equally.

Abstract

Background and Purpose—The question whether cerebral microbleeds (CMBs) visible on MRI in acute stroke increase the risk for intracerebral hemorrhages (ICHs) or worse outcome after thrombolysis is unresolved. The aim of this study was to analyze the impact of CMB detected with pretreatment susceptibility-weighted MRI on ICH occurrence and outcome.

Methods—From 2010 to 2013 we treated 724 patients with intravenous thrombolysis, endovascular therapy, or intravenous thrombolysis followed by endovascular therapy. A total of 392 of the 724 patients were examined with susceptibility-weighted MRI before treatment. CMBs were rated retrospectively. Multivariable regression analysis was used to determine the impact of CMB on ICH and outcome.

Results—Of 392 patients, 174 were treated with intravenous thrombolysis, 150 with endovascular therapy, and 68 with intravenous thrombolysis followed by endovascular therapy. CMBs were detected in 79 (20.2%) patients. Symptomatic ICH occurred in 21 (5.4%) and asymptomatic in 75 (19.1%) patients, thereof 61 (15.6%) bleedings within and 35 (8.9%) outside the infarct. Neither the existence of CMB, their burden, predominant location nor their presumed pathogenesis influenced the risk for symptomatic or asymptomatic ICH. A higher CMB burden marginally increased the risk for ICH outside the infarct (P=0.048; odds ratio, 1.004; 95% confidence interval, 1.000–1.008).

Conclusions—CMB detected on pretreatment susceptibility-weighted MRI did not increase the risk for ICH or worsen outcome, even when CMB burden, predominant location, or presumed pathogenesis was considered. There was only a small increased risk for ICH outside the infarct with increasing CMB burden that does not advise against thrombolysis in such patients.