Using cryotherapy to stabilize vulnerable coronary plaques in heart patients

Clinical Investigation of Intracoronary Cryotherapy Using the CryoTherapy System (CTS) for High-risk Plaque in Patients With (Non-)ST-segment Elevation Myocardial Infarction (NSTEMI) or Unstable Angina

This study is testing if a new freezing treatment can help heart patients with unstable plaque in their arteries feel safer and lower their risk of serious heart problems.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 30 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Cryotherapeutics SA (Industry-sponsored)
• Locations: 5 sites (Tbilisi and 4 other locations)
• Trial ID: NCT05600088 on ClinicalTrials.gov

What this trial studies

The POLARSTAR study evaluates the safety and feasibility of the CryoTherapy System (CTS) for treating vulnerable plaque lesions in patients with acute coronary syndrome, specifically those with NSTEMI or unstable angina. The CTS applies localized freezing to high-risk plaque lesions using a balloon catheter, aiming to stabilize them and reduce the risk of rupture that could lead to major cardiac events. Participants will undergo a Coronary CT-angiography (CCTA) to identify suitable lesions, followed by treatment and clinical follow-up for one year, including additional imaging assessments at 3 and 9 months post-procedure.

Who should consider this trial

Good fit: Ideal candidates include adults with NSTEMI or unstable angina who have undergone successful PCI and have high-risk non-culprit plaque lesions.

Not a fit: Patients without acute coronary syndrome or those who do not have high-risk plaque lesions may not benefit from this treatment.

Why it matters

Potential benefit: If successful, this approach could significantly reduce the risk of heart attacks in patients with vulnerable coronary plaques.

How similar studies have performed: While this approach is innovative, similar studies exploring cryotherapy for coronary plaque stabilization have shown promising results.

Eligibility criteria

Inclusion Criteria:

1. Subject is at least 18 years old.
2. Subject has acute cardiac pain/angina consistent with acute coronary syndrome eligible for coronary angiography meeting one of the following criteria:

   1. (Non-)ST-segment elevation myocardial infarction ((N)STEMI) with rise/fall of cardiac enzymes (troponin I or T) with at least one value above the 99th percentile of the upper reference limit requiring PCI within 72 hours from diagnosis
   2. Unstable angina
3. Successful PCI (defined as diameter stenosis less than 30% and TIMI 3 flow on final angiography without procedural complication) of the culprit lesion.
4. Subject has at least one high-risk plaque meeting the criteria below:

   1. Located in a non-culprit vessel,
   2. High-risk plaque lesion on CCTA and at least one of the following features:

      1. Presence of low-attenuation plaque (HU\<50) and/or
      2. Positive remodelling (remodelling index \>1.1) and/or
      3. Napkin ring sign and/or
      4. Plaque burden ≥70%
   3. Lesion length ≤ 20 mm.
   4. Diameter stenosis on invasive angiography between 30% and 70% on coronary angiogram or negative physiology assessment (FFR\>0.80 or non-hyperemic pressure ratios (NHPR) \>0.89).
   5. Reference vessel diameter (RVD) \< 3.75 mm and \> 2.00 mm in diameter
   6. Investigator considers that lesions are accessible.
   7. If more than two suitable lesions available, investigator will select the most appropriate lesion for cryotherapy treatment.
5. Subject is able to provide consent and has signed and dated the informed consent form.

Exclusion Criteria:

1. Subject is hemodynamically unstable (cardiogenic shock, hypotension needing inotropes, hypoxia needing intubation, refractory ventricular arrhythmias, and IABP).
2. Subject has ongoing ST-segment elevation myocardial infarction.
3. Subject had a procedural complication during the Acute coronary syndrome (ACS) PCI procedure.
4. Subject has history of Coronary Artery Bypass Graft (CABG) or planned CABG within 12 months after the index procedure.
5. Subject has known reduced Left Ventricular Ejection Fraction \< 30%.
6. Subject has known severe valvular heart disease.
7. Subject has known severe renal insufficiency (eGFR \<30 ml/min/1.72 m2).
8. Subject has any life-threatening conditions or medical comorbidity resulting in life expectancy \< 12 months.
9. Subject is currently participating in another clinical investigation that has not yet reached its primary endpoint.
10. Subject is pregnant or lactating, or NOT surgically sterile (tubal ligation or hysterectomy) or NOT postmenopausal for at least 6 months or is a female with childbearing potential without effective contraception (pill, patch, ring, diaphragm, implant and intrauterine device).

Angiographic exclusion criteria:

1. Visible distal embolization/no-reflow following culprit lesions PCI.
2. Left main coronary artery disease (visual diameter stenosis \> 50%).
3. Stent thrombosis/restenosis as a culprit lesion.
4. CTS lesion involving a bifurcation (defined as lesions involving side branches \>2.0 mm).
5. Angiographic or CCTA evidence of severe calcification and/or marked tortuosity of the index vessel and/or lesion.
6. Thrombotic lesions
7. Ostial lesions

Where this trial is running

Tbilisi and 4 other locations

• Israeli-Georgian Research Clinic Helsicore — Tbilisi, Georgia (Recruiting)
• Tbilisi Heart Center — Tbilisi, Georgia (Recruiting)
• Hospital of Lithuanian University of health sciences Kauno Klinikos — Kaunas, Lithuania (Recruiting)
• Klaipèda University Hospital — Klaipèda, Lithuania (Recruiting)
• Vilnius University Hospital Santaros Klinikos — Vilnius, Lithuania (Recruiting)

Study contacts

• Principal investigator: Irakli Gogorishvili, MD — Israeli_Georgian research Clinic Helsicore, Tbilisi, Georgia
• Study coordinator: Danny Detiege, RN

Conditions Coronary Artery Disease; Coronary Syndrome; Cryotherapy Effect; Myocardial Infarction; Myocardial Disease; Atherosclerosis, Coronary