The primary objective of this study is to determine the feasibility and safety of achieving rapid hypothermia with the Proteus Intravascular Temperature Management (IVTM) system for patients experiencing acute ischemic stroke due to a large vessel occlusion.



Eligible Ages
Between 18 Years and 85 Years
Eligible Genders
Accepts Healthy Volunteers

Inclusion Criteria

All Inclusion Criteria must be answered YES for Patient to be eligible.

1. Age ≥18 and ≤85;

2. Signs and symptoms consistent with an acute ischemic stroke with anterior circulation large vessel occlusion (M1 MCA, carotid-terminus occlusion, Tandem occlusion allowed (Extracranial ICA+carotid T or M1 MCA) as determined by CT imaging; (i.e., hyper dense sign on non-contrast CT or CT angiogram);

3. Ability to perform arterial puncture within 24 hours from symptom onset or last known normal (LKN);

4. ASPECTS score of 5-10 on non-contrast CT of the brain if under 80 years; ASPECTS 8-10 if age 80-85;

5. Candidate for on label endovascular thrombectomy therapy;

6. No contraindications to general anesthesia, conscious sedation or allergies to any components associated with the anticipated diagnostic or treatment procedures that cannot be treated;

7. A pre-stroke modified Rankin Scale (mRS) of 0 or 1;

8. Baseline CT scan shows no hemorrhage;

9. NIH Stroke Scale (NIHSS) greater than or equal to 8;

10. Patient is capable of complying with study procedures and agrees to complete all required study procedures, study visits and associated activities;

11. Legally authorized representative must be able to understand and give written informed consent. Patient will assent if capable. Patient may be re-consented once it is established that there is no memory loss or cognitive impairment.

Exclusion Criteria

All Exclusion Criteria must be answered NO to be eligible

1. Female patients of childbearing potential who are known to be or may be pregnant;

2. The patient has a known history of bleeding diathesis, coagulopathy, cryoglobulinemia, sickle cell anemia, or will refuse blood transfusions; history of genetically confirmed hypercoagulable syndrome

3. The patient has a height of < 1.5 meters (4 feet 11 inches);

4. Use of warfarin with international normalized ratio (INR) > 1.7;

5. Blood clinical chemistry potassium (K+) < 2.7;

6. History of severe dementia and currently taking medication for cognitive impairment or behavior disorder;

7. End stage renal disease on hemodialysis;

8. Known presence of an inferior vena cava (IVC) filter;

9. Contrast dye allergy with history of anaphylaxis, known serious sensitivity to contrast agents or any condition in which angiography is contraindicated;

10. Known to have contraindications to radiological imaging;

11. Known allergy to meperidine or buspar or dexmedetomidine;

12. Sustained hypertension (SBP > 185 or DBP > 110 unable to be treated with a continuous infusion, e.g., nicardipine);

13. Baseline CT/MR showing evidence of arterial vasculitis or dissection;

14. Baseline CT/MR evidence of multiple vascular territory acute stroke;

15. Excessive tortuosity of cervical vessels;

16. Intracranial stent in area that may impact Recanalization;

17. Presence of any other serious comorbidity that would be likely to impact life expectancy to less than 6 months or limit Patient cooperation or study compliance;

18. Concurrent participation in an investigational clinical study (excluding registries) that has not completed the follow-up period or planned participation in another study within the next 3 months;

19. Patient has any other condition(s) or circumstance(s) that, in the judgement of the investigator, might interfere with or impact the collection of high quality data, or with the completion of follow up requirements within the study windows;

20. Patients without a legally authorized representative to sign the consent form will be excluded.

Study Design

Study Type
Intervention Model
Parallel Assignment
Primary Purpose
None (Open Label)

Arm Groups

ArmDescriptionAssigned Intervention
Cooling + Recanalization
The subjects will be considered to be enrolled in the Test Arm of the trial when all inclusion and exclusion criteria have been met, the informed consent form has been signed, and randomization to the Test Arm of the trial to allow cooling with the Proteus IVTM System before and after recanalization.
  • Device: Proteus IVTM
    Cooling with the ZOLL® Circulation Proteus® catheter and the ZOLL® Intravascular Temperature Management system to initiate and maintain hypothermia for 6 hours as an adjunct to endovascular Recanalization.
Active Comparator
Recanalization only
The subjects will be considered to be enrolled in the Control Arm of the trial when all inclusion and exclusion criteria have been met, the informed consent form has been signed, and randomization to the Control Arm of the trial to allow recanalization only.
  • Procedure: Recanalization only
    Standard of Care for recanalization

Recruiting Locations

University of Maryland Medical Center
Baltimore, Maryland 21201
Lakshman Kalasapudi, M.A.

More Details

ZOLL Circulation, Inc., USA

Study Contact

Shweta Kalpa, MD


Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.