Optimizing the Diagnosis of Heparin Induced Thrombocytopenia (HIT)
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|ClinicalTrials.gov Identifier: NCT03148912|
Recruitment Status : Recruiting
First Posted : May 11, 2017
Last Update Posted : July 17, 2019
|Condition or disease||Intervention/treatment||Phase|
|Heparin-induced Thrombocytopenia (HIT)||Diagnostic Test: Diagnostic algorithm||Not Applicable|
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||180 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Official Title:||Optimizing the Diagnosis of Heparin Induced Thrombocytopenia Using Quantified Anti-Platelet Factor 4 Immunological Testing: A Pilot Multicentre Cohort Study|
|Actual Study Start Date :||November 23, 2018|
|Estimated Primary Completion Date :||June 2020|
|Estimated Study Completion Date :||October 2020|
Experimental: diagnostic algorithm
Optimizing the interpretation of the more readily available anti-PF4 assay would reduce the reliance on functional testing/ confirmatory testing (Serotonin Release Assay, SRA) and the number of patients exposed to unnecessary changes in anticoagulation therapy while awaiting the timely functional test results
Diagnostic Test: Diagnostic algorithm
The treating physician will complete an enrollment assessment including the 4T score pretest probability assessment14. All patients will have laboratory testing for HIT anti-PF4 as well as SRA testing. Results of the anti-PF4 assay (OD value) will be available to the treating physician who will be instructed to follow the study diagnostic algorithm
- Recruitment [ Time Frame: 2 years ]The pilot will be considered feasible if recruitment of at least 7.5 patients per month (total between the two sites) is achieved.
- False negative management failures [ Time Frame: 2 years ]The rate of false negative 'management failures' where the study protocol concludes HIT unlikely but SRA (reference standard laboratory test) is positive for HIT (≥50% Serotonin release).
- Major arterial and venous thromboembolism events [ Time Frame: 24 hours of baseline and 24 of study enrolment ]Events will be ascertained from the date of study consent. However, venous or arterial thrombotic events detected on investigations ordered within 24 hours of study entry will be captured as baseline events and will be counted separately from thrombotic events which occur after the initial 24 hours of study enrolment.
- Proximal deep vein thrombosis [ Time Frame: 2 years ]Testing performed because of symptoms in a patient with (new) non-compressibility of the common femoral vein, popliteal vein or calf trifurcation vein of the leg on ultrasound; or new non-compressibility or visualization of thrombus in the jugular vein, subclavian vein or axillary vein on ultrasound; or an intraluminal defect seen in one more than one view in proximal leg or arm veins on venography will be diagnostic for deep vein thrombosis.
- Pulmonary embolism [ Time Frame: 2 years ]Testing performed because of symptoms in a patient with a high probability lung scan (i.e. at least one segmental perfusion mismatch) or CT pulmonary angiography (i.e. intraluminal filling defect in the main, lobar or segmental pulmonary arteries) will be diagnostic for pulmonary embolism.
- Stroke [ Time Frame: 2 years ]New infarction or hemorrhagic event confirmed on CT or MRI.
- Myocardial infarction [ Time Frame: 2 years ]Detection of rise and/or fall of cardiac biomarkers (preferably troponin) with at least one value above the 99th percentile of the upper reference limit together with evidence of myocardial ischemia with at least one of the following: Symptoms of ischemia for ≥ 20 minutes ECG changes indicative of new ischemia: new ST-T changes ≥0.1 mV or new left bundle branch block Development of pathological Q waves in the ECG; Imaging evidence of new loss of viable myocardium or new regional wall motion abnormality.
- Systemic arterial embolism [ Time Frame: 2 years ]Acute vascular occlusion confirmed on ultrasound or angiography Adrenal hemorrhagic infarction (indicating adrenal vein thrombosis) - radiologic diagnosis on ultrasound or CT.
- Death [ Time Frame: 30 days of follow up ]Due to major arterial or venous thromboembolism within 30days of follow up and major and minor bleeding.
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03148912
|Contact: Chantal Rockwell, BA||613-737-8899 ext firstname.lastname@example.org|
|Principal Investigator:||Lisa Duffett, MSc, MD||Ottawa Hospital Research Institute|