In Vivo Detection of Circulating Clots in Patients With Thromboembolism

Study Overview
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Brief Summary
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Subjects with thromboembolic disease or at high-risk for thromboembolic conditions diagnosed with ultrasound or other standard of care techniques will be recruited to estimate the feasibility of a device to detect in vivo CBCs.

Detailed Description
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There are no current gold standards to detect circulating blood clots. The sensitivity of most current methods to detect CBCs is poor when low numbers are present in the host. A novel method of detecting circulating blood clots, PAFC, may improve detection of CBCs and, if so, ultimately may reduce complications related to previously undetected clots.

Official Title
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In Vivo Detection of Circulating Clots in Patients With Thromboembolism

Conditions
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Thromboembolism

Intervention / Treatment
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* Device: Photoacoustic Flow Cytometry


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Men and women, 18 years old and older. Evidence of current venous or arterial thromboembolic disease diagnosed by standard of care clinical, radiographic, or laboratory testing or acute ischemic stroke. Informed consent provided by the subject. Exclusion Criteria Pulmonary embolus with a need for mechanical ventilation or other ventilator support (may be on oxygen delivered by nasal cannula or mask at an FiO2 of ≤ 0.40) Acute coronary syndrome (including unstable angina) Significant cardiac arrhythmia (may have atrial fibrillation controlled with medication) Intracardiac thrombus Any embolus or thrombus requiring vascular surgery or interventional radiology to attempt acute embolectomy or thrombectomy Sickle cell disease with vaso-occlusive crisis Sepsis or life-threatening infection Traumatic injury requiring hospitalization (within 30 days prior to enrollment) Pregnancy or breastfeeding Severe mental illness Other conditions deemed by the investigators to put the subject at greater risk

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Procedure<br>Subjects will receive PAFC procedure | Device: Photoacoustic Flow Cytometry<br>* Detection of circulating blood clots<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparison of Circulating blood clots detected by PAFC with D-dimer levels in patients with known venous thromboembolic disease - Positive PA peaks | Measurement of in vivo CBC-associated positive PA peaks in a signal trace of patients who have been diagnosed with conventional methods. | 30 days | 
| Comparison of Circulating blood clots detected by PAFC with D-dimer levels in patients with known venous thromboembolic disease - Negative PA peaks | Measurement of in vivo CBC-associated negative PA peaks in a signal trace of patients who have been diagnosed with conventional methods. | 30 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Relationship between PA peaks and circulating blood clots | PAFC will be compared with the fibrin degradation fragment D-dimer to indicate the presence of a blood clot undergoing dissolution. | 30 days | 
| Safety of the PAFC method - skin sensitivity | The safety of the PAFC device through estimation of the sensitivity of the individual's skin to laser radiation will be indicated by a possible warming feeling or tingling sensation. | 30 days | 
| Safety of the PAFC method - change in skin property | The safety of the PAFC device through estimation of the change to the skin's property after laser exposure measured by appearance of possible red spots in the irradiated local area | 30 days |