Background: Chagas disease is an important cause of heart failure (HF) and stroke, affecting over six million people. High intensity transient signals (HITS) are detected on transcranial Doppler (TCD) in patients with Chagas disease, but the effect of antithrombotic treatment on HITS is unknown. The aim of this study was to evaluate whether acetylsalicylic acid (ASA) reduces the frequency and number of HITS in patients with chagasic HF. Methods: Proof-of-principle pilot prospective, randomized, open and blinded endpoint clinical trial (PROBE), where patients with both Chagas and HITS were randomized 2:1 to ASA 300 mg for seven days and standard HF treatment or standard HF treatment alone (control group). The primary outcome was the proportion of HITS after one week, analyzed using chi-squared test. Results: 373 patients with HF were evaluated, HITS occurred in 22/190 (12%) chagasic patients and in 16/183 (8%) non-chagasic patients (p=0.531). Twelve of the 22 (54%) chagasic patients were randomized to treatment with ASA (n = 8) or without ASA (n = 4). Two patients in the control group (50%) persisted with HITS after 7 days of treatment, compared to none in the ASA group, p=0.028. Median number of HITS decreased from 3.5 to 0 with ASA (p=0.012) and 4.0 to 0.5 in the control group (p=0.095), with no significant between-group difference (p=0.262). No adverse events were reported. Conclusion: In this pilot clinical trial, ASA reduced the proportion of HITS in patients with Chagas disease HF.

The authors have declared no competing interest.

NCT01650792

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The study was approved on February 13, 2014 by the ethics committee of the Professor Edgard Santos University Hospital - Federal University of Bahia, Brazil and all patients signed the informed consent form, number: 529140.

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