Skip to main content
OpenTrials
Recruiting

NCT Number: NCT05147792

The CONFORM Pivotal Trial

The CLAAS® device will be evaluated for safety and efficacy by establishing its performance is non-inferior to the commercially available WATCHMAN® and Amulet™ left atrial appendage closure devices in patients with non-valvular atrial fibrillation. Patients who are eligible for the trial will be randomized to receive either the CLAAS device or the WATCHMAN or Amulet™ devices and will be followed for 5 years after device implant.

Recruiting

Interested in participating?

Request Info

Key information

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Nemocnice Na Homolce, Prague, Czechia

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Male or non-pregnant female aged ≥18 years
  • Documented non-valvular AF (paroxysmal, persistent, or permanent)
  • High risk of stroke or systemic embolism, defined as CHA2DS2-VASc score of ≥ 3
  • Has an appropriate rationale to seek a non-pharmacologic alternative to long-term oral anticoagulation
  • Deemed by the site investigator to be suitable for short term oral anticoagulation therapy but deemed less favorable for long-term oral anticoagulation therapy.
  • Deemed appropriate for LAA closure by the site investigator and a clinician not a part of the procedural team using a shared decision-making process in accordance with standard of care
  • Able to comply with the protocol-specified medication regimen and follow-up evaluations
  • The subject (or legally authorized representative, where allowed) has been informed of the nature of the study, agrees to its provisions, and has provided written informed consent approved by the appropriate institutional review board (IRB)/Regional Ethics Board (REB)/Ethics Committee (EC).

Exclusion criteria

  • Pregnant or nursing patients and those who plan pregnancy in the period up to one year following the index procedure. Female patients of childbearing potential must have a negative pregnancy test (per site standard test) within 7 days prior to index procedure.
  • Anatomic conditions that would prevent performance of an LAA occlusion procedure (e.g., atrial septal defect (ASD) requiring closure, high-risk patent foramen ovale (PFO) requiring closure, a highly mobile inter-atrial septal aneurysm precluding a safe TSP, presence of a PFO/ASD closure device, history of surgical ASD repair or history of surgical LAAO closure)
  • Atrial fibrillation that is defined by a single occurrence or that is transient or reversible (e.g., secondary thyroid disorders, acute alcohol intoxication, trauma, recent major surgical procedures)
  • A medical condition (other than atrial fibrillation) that mandates long-term oral anticoagulation (e.g., history of unprovoked deep vein thrombosis or pulmonary embolism, or prosthetic mechanical heart valve)
  • History of bleeding diathesis or coagulopathy, or patients in whom antiplatelet and/or anticoagulant therapy is contraindicated
  • Documented active systemic infection
  • Symptomatic carotid artery disease (defined as >50% stenosis with symptoms of ipsilateral transient or visual TIA evidenced by amaurosis fugax, ipsilateral hemispheric TIAs or ipsilateral stroke); if subject has a history of carotid stent or endarterectomy the subject is eligible if there is <50% stenosis noted at the site of prior treatment
  • Recent (within 30 days of index procedure) or planned (within 60 days post-procedure) cardiac or major non-cardiac interventional or surgical procedure
  • Recent (within 30 days of index procedure) stroke or transient ischemic attack
  • Recent (within 30 days of index procedure) myocardial infarction
  • Vascular access precluding delivery of implant with catheter-based system
  • Severe heart failure (New York Heart Association Class IV)
  • Prior cardiac transplant, history of mitral valve replacement or transcatheter mitral valve intervention, or any prosthetic mechanical valve implant
  • Renal insufficiency, defined as estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2 (by the Modification of Diet in Renal Disease equation)
  • Platelet count <75,000 cells/mm3 or >700,000 cells/mm3, or white blood cell count <3,000 cells/mm3
  • Known allergy, hypersensitivity or contraindication to aspirin, heparin, or that would preclude any P2Y12 inhibitor therapy, or to device materials (e.g., nickel, titanium), or the subject has contrast sensitivity that cannot be adequately pre-medicated
  • Actively enrolled or plans to enroll in a concurrent clinical study in which the active treatment arm may confound the results of this trial
  • Unable to undergo general anesthesia
  • Known other medical illness or known history of substance abuse that may cause non-compliance with the protocol or protocol-specified medication regimen, confound the data interpretation, or is associated with a life expectancy of less than 5 years
  • A condition which precludes adequate transesophageal echocardiographic assessment

Echo exclusion criteria:

  • Left atrial appendage anatomy which cannot accommodate a commercially available control device or the CLAAS Implant per manufacturer IFU (e.g., the anatomy and sizing must be appropriate for both the investigational (CLAAS) and a commercially available device in order to be enrolled in the trial)
  • Intracardiac thrombus or dense spontaneous echo contrast consistent with thrombus, as visualized by TEE
  • Left ventricular ejection fraction (LVEF) <30%
  • Moderate or large pericardial effusion >10 mm or symptomatic pericardial effusion, signs or symptoms of acute or chronic pericarditis, or evidence of tamponade physiology
  • Atrial septal defect that warrants closure
  • High risk patent foramen ovale (PFO), defined as an atrial septal aneurysm (excursion >15 mm or length > 15 mm) or large shunt (early [within 3 beats] and/or substantial passage of bubbles, e.g., >20)
  • Moderate or severe mitral valve stenosis (mitral valve area <1.5 cm2)
  • Complex atheroma with mobile plaque of the descending aorta and/or aortic arch
  • Evidence of cardiac tumor

Treatment and study plan

CLAAS

Device

CLAAS

WATCHMAN left atrial appendage closure device / Amulet left atrial appendage occluder

Device

WATCHMAN left atrial appendage closure device / Amulet left atrial appendage occluder

Primary outcomes

  1. Procedure-related complications, all-cause death, major bleeding

    Time frame: 12 months

    The primary safety endpoint is a composite of 1) major procedure-related complications including a) cardiac perforation, b) pericardial effusion requiring drainage, c) ischemic stroke, d) device embolization, and e) major vascular complications, or 2) major bleeding, or 3) all-cause death

  2. Ischemic stroke and systemic embolism

    Time frame: 18 months

    The primary effectiveness endpoint is a composite of ischemic stroke and systemic embolism through 18 months.

Secondary outcomes

  1. Procedure-related complications, all-cause death, major bleeding

    Time frame: 5 years

    All elements of the Primary Safety Endpoint will be reported descriptively for all subjects through 5 years: a composite of 1) major procedure-related complications including a) cardiac perforation, b) pericardial effusion requiring drainage, c) ischemic stroke, d) device embolization, and e) major vascular complications, or 2) major bleeding, or 3) all-cause death

  2. Device Success

    Time frame: Procedure

    A secondary performance and efficacy endpoint is Device Success, defined as LAAO device deployed and implanted in correct position

  3. Technical success

    Time frame: 45 days

    A secondary performance and efficacy endpoint is Technical Success, defined as Device Success, complete closure or peri-device residual leak ≤5 mm in width on TEE, as evaluated by independent imaging core lab without device-related complications [evaluated post-procedure].

  4. Procedure success

    Time frame: 7 Days

    A secondary performance and efficacy endpoint is Procedure Success, defined as Technical Success without in-hospital major procedure-related complications (excluding minor device embolization) evaluated at hospitalization or at 7 days whichever is first.

  5. Embolic Events

    Time frame: 12 Months, 18 Months

    A secondary performance and efficacy endpoint is Embolic Events, defined as ischemic stroke as defined by NeuroARC (29) and systemic thromboembolism characterized as any thromboemboli in the arterial system.

  6. Closure Success

    Time frame: 12 months

    A secondary performance and efficacy endpoint is Closure Success at 12 months based upon each of the following criteria: a) demonstration of peri-device leak </=5 mm, and b) demonstration of peri-device leak </=3 mm

Study contacts

Contact information is provided by the study sponsor or research team.

Sarah Gallagher

CONTACT

[email protected]

952-270-8356

Sponsors and collaborators

Lead sponsor

Conformal Medical, Inc

Industry

Registry information

Official study title

An Evaluation of the Safety and Effectiveness of the Conformal CLAAS System for Left Atrial Appendage Occlusion

Important dates

Study start
2022
Primary completion
2028
Study completion
2031
First posted
Dec 7, 2021
Registry last updated
Jul 6, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Published trials that share one or more normalized conditions with this study.