DiamondTemp™ System for the Treatment of Persistent Atrial Fibrillation

Not Applicable

Completed

• Conditions: Persistent Atrial Fibrillation; Atrial Fibrillation
• Interventions: Device: Radiofrequency Ablation

• Registration Number: NCT03643224
• Lead Sponsor: Medtronic Cardiac Ablation Solutions

Brief Summary

The purpose of the Diamond-AF II study is to establish the safety and effectiveness of the DiamondTemp Ablation System for the treatment of drug refractory, symptomatic persistent atrial fibrillation in patients.

Detailed Description

The DIAMOND-AF II Study is a prospective, non-randomized (single-group assignment) trial being performed at multiple centers in the United States, Canada and Europe to evaluate the safety and effectiveness of the DiamondTemp Ablation System for the treatment of patients with persistent atrial fibrillation.

Study Timeline

• Study First Submitted: 2018-08-20
• Study First Submitted QC: 2018-08-21
• Study First Posted: 2018-08-22
• Study Start: 2018-09-20
• Primary Completion: 2024-10-31
• Study Completion: 2024-10-31
• Status Verified: 2025-04
• Last Update Submitted: 2025-04-21
• Last Update Posted: 2025-04-24

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 376

Inclusion Criteria

1. Above eighteen (18) years of age or of legal age to give informed consent specific to state and national law.
2. Subjects with a history of documented symptomatic, persistent atrial fibrillation with 1) a physician's note documenting a continuous AF episode lasting longer than 7 days but less than 12 months and 2) a 24-hour Holter within 90 days of the ablation procedure showing continuous AF.
3. Refractory, intolerant or contraindicated to at least one Class I or III anti-arrhythmic (AAD) drug.
4. Suitable candidate for intra-cardiac mapping and ablation of arrhythmia.
5. Subject agrees to comply with study procedures and be available (geographically stable) for follow-up visits for at least 12 months after enrollment.
6. Subject is willing and able to provide written consent.

Exclusion Criteria

At time of enrollment and/or prior to procedure:

1. Continuous AF >12 months (long-standing persistent AF)

2. Paroxysmal AF with longest episode <7 days

3. AF secondary to electrolyte imbalance, thyroid disease or reversible or non-cardiac cause

4. Rheumatic heart disease

5. Severe mitral regurgitation

6. Hypertrophic cardiomyopathy

7. LA diameter >5.5 cm

8. Left ventricular ejection fraction (LVEF) <40%

9. Currently NYHA Class III or IV or exhibits uncontrolled heart failure

10. Body Mass Index (BMI) >42 kg/m2.

11. LA ablation, septal closure device or mitral valve surgical procedure at any time prior to enrollment

12. Presence of intramural thrombus, tumor or abnormality that precludes vascular access, catheter introduction or manipulation

13. Coagulopathy, bleeding diathesis or suspected procoagulant state

14. Sepsis, active systemic infection or fever (>100.5 oF / 38 oC) within a week prior to the ablation procedure

15. Significant restrictive or obstructive pulmonary disease or chronic respiratory condition

16. Renal failure requiring dialysis or renal compromise that in the investigator's judgement would increase risk to the subject or deem the subject inappropriate to participate in the study.

17. Known allergies or intolerance to anticoagulant and antiplatelet therapies to be used in conjunction with the study or contrast sensitivity that cannot be adequately pre-treated prior to the ablation procedure.

18. Positive pregnancy test results for female subjects of childbearing potential or breast feeding.

19. Enrollment in a concurrent clinical study that in the judgement of the investigator would impact study outcomes.

20. Acute or chronic medical condition that in the judgment of the investigator would increase risk to the subject or deem the subject inappropriate to participate in the study.

21. Life expectancy <12 months based on medical history or the medical judgement of the investigator.

    Within 1 month of enrollment or just prior to procedure:

22. Documented LA thrombus upon imaging

23. Creatinine >2.5mg/dl or creatinine clearance <30mL/min

    Within 3 months of enrollment:

24. Significant gastrointestinal (GI) bleed

25. Myocardial infarction (MI), unstable angina, cardiac surgery or coronary intervention

    Within 6 months of enrollment:

26. Coronary artery bypass graft (CABG) procedure

27. Implant procedure performed for ICD, CRT leads or pacemaker

28. Documented stroke, CVA, TIA or suspected neurological event

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Experimental	Radiofrequency Ablation	Radiofrequency Ablation. Catheter ablation to treat persistent atrial fibrillation using temperature-controlled ablation catheter

Primary Outcome Measures

Name	Time	Method
Incidence of device or procedure related clinically significant tamponade/perforation measured at 30 days in all subjects.	30 days after the index ablation procedure	Freedom from clinically significant tamponade/perforation occurring through 30 days.
Incidence of device or procedure related Serious Adverse Events measured at 7 days in all subjects	7 days after the index ablation procedure	Freedom from a composite of pre-specified Serious Adverse Events
Incidence of symptomatic pulmonary vein stenosis and atrioesophageal fistula through 6-months in all subjects.	6 months after the index ablation procedure	Freedom from symptomatic pulmonary vein stenosis and atrioesophageal fistula through 6-months
Incidence of documented symptomatic atrial fibrillation, atrial flutter and atrial tachycardia episodes for all subjects.	Between the blanking period (3-month follow-up post-ablation procedure) through the end of the effectiveness evaluation period (12-month follow-up post-ablation procedure).	Freedom from documented symptomatic atrial fibrillation (AF), atrial flutter\* (AFL) and atrial tachycardia (AT) episodes following the blanking period through the end of the effectiveness evaluation period.

Secondary Outcome Measures

Name	Time	Method
Incidence of device or procedure related Serious Adverse Events measured at 30 days in all subjects.	30 days after the index ablation procedure	Freedom from a composite of pre-specified Serious Adverse Events
Incidence of asymptomatic AF, AFL* or AT episodes through the effectiveness evaluation period lasting ≥30 seconds in duration by ECG or ECG monitoring system	Between the blanking period (3-month follow-up post-ablation procedure) through the end of the effectiveness evaluation period (12-month follow-up post-ablation procedure).	Freedom from documented asymptomatic AF, AFL\* or AT episodes through the effectiveness evaluation period lasting ≥30 seconds in duration by ECG or ECG monitoring system
Total time to achieve initial PVI (minutes)	Day of index ablation procedure	Time to achieve initial PVI at index procedure (minutes), defined as time of delivery of first RF ablation with the investigational catheter until confirmation of PVI via entrance block following a 20-minute waiting period.
Total treatment device time (minutes)	Day of index ablation procedure	Total treatment device time (minutes), defined as time of delivery of first RF ablation with investigational catheter to removal of the investigational catheter.
Mean duration of RF ablations (seconds)	Day of index ablation procedure	Mean duration of RF ablations (seconds)
Incidence of re-hospitalizations due to atrial fibrillation recurrence.	Between the blanking period (3-month follow-up post-ablation procedure) through the end of the effectiveness evaluation period (12-month follow-up post-ablation procedure).	Number of re-hospitalizations due to atrial fibrillation recurrence after blanking period.
Incidence of documented symptomatic atrial fibrillation, atrial flutter and atrial tachycardia episodes in the absence of class I and II anti-arrhythmic drug therapy for all subjects.	Between the blanking period (3-month follow-up post-ablation procedure) through the end of the effectiveness evaluation period (12-month follow-up post-ablation procedure).	Freedom from documented symptomatic and asymptomatic AF, AT and AFL episodes following the blanking period through 12-month follow-up post-ablation procedure in the absence of class I and III anti-arrhythmic drug therapy.
Accumulated changes in Quality of Life (QOL) using the Atrial Fibrillation Effect on Quality of Life (AFEQT) Questionnaire	Between 6 months and 12 months after the index ablation procedure	Accumulated changes in QOL using the AFEQT Questionnaire from baseline through 6 and 12 months following ablation procedure.; Section 1 measures occurrence of atrial fibrillation by asking the subject if they are in atrial fibrillation. If they answer "No", it asks for the last time they had atrial fibrillation ranging from the subject were never aware of having atrial fibrillation (minimum) to more than 1 year ago (maximum).; Section 2 measures how atrial fibrillation affects the subject's quality of life by asking a series of 20 questions that the subject rates on a scale of 1 to 7, how much was the subject bothered by their atrial fibrillation, one being "Not at all bothered" and 7 being "Extremely bothered".
Total fluoroscopy time (minutes)	Day of index ablation procedure	Total fluoroscopy time (minutes)
Incidence of asymptomatic AF, AFL* or AT episodes through the effectiveness evaluation	Between the blanking period (3-month follow-up post-ablation procedure) through the end of the effectiveness evaluation period (12-month follow-up post-ablation procedure).	Freedom from documented asymptomatic AF, AFL\* or AT episodes during effectiveness evaluation period in the absence of class I and III anti-arrhythmic drug therapy
Rate of single procedure success	12 months after the index ablation procedure	Rate of single procedure success defined as the rate of subjects treated with one single ablation procedure for the entire enrollment period and with freedom from documented symptomatic AF, AT and AFL\* at 12 months.
Rate of occurrence of electrically reconnected PVs following a 20-minute waiting period	Day of index ablation procedure	Rate of occurrence of electrically reconnected PVs following a 20-minute waiting period assessed by entrance block at index procedure.
Ability to perform first-pass PV antral isolation	Day of index ablation procedure	Ability to perform first-pass PV antral isolation
Incidence of asymptomatic pericardial effusion of 1cm or more in size	30 days after the index ablation procedure	Rate of asymptomatic pericardial effusion of 1cm or more in size as documented by echocardiography up to 30 days following the index procedure
Total procedure time (minutes)	Immediately after the index ablation procedure	Total procedure time (minutes), defined as time of investigational catheter insertion into the vasculature to time of last procedural ablation catheter removed.
Mean cumulative RF Time (minutes).	Day of index ablation procedure	Mean cumulative RF Time (minutes).
Rate of acute procedural success	Day of index ablation procedure	Rate of acute procedural success, defined as confirmation of electrical isolation of PVs via assessment of entrance block at least 20 minutes following the last ablation around the respective PV
Neurological changes measured using the National Institutes of Health Stroke Scale (NIHSS)	Between baseline and 12 months after the index ablation procedure	The NIHSS which is comprised of 11 items, each of which scores a specific ability between a 0 and 4. For each item, a score of 0 typically indicates normal function in that specific ability, while a higher score is indicative of some level of impairment. The individual scores from each item are summed in order to calculate a patient's total NIHSS score. The maximum possible score is 42, with the minimum score possible is 0.; 1a. Level of Consciousness (LOC) 0 - 3; 1b. LOC Questions 0 - 2; 1c. LOC Commands 0 - 2 2. Best Gaze 0 - 2 3. Visual 0 - 3 4. Facial Palsy 0 - 3 5. Motor Arm. 0 - 4 or UN = Amputation or joint fusion. Scored for both left and right arms.; 6. Motor Leg. 0 - 4 or UN = Amputation or joint fusion. Scored for both left and right legs.; 7. Limb Ataxia. 0 - 2 or UN = Amputation or joint fusion 8. Sensory. 0 - 2 9. Best Language. 0 - 3 10. Dysarthria. 0 - 2 or UN = Intubated or other physical barrier. 11. Extinction and Inattention. 0 - 2
Total fluid infused through the investigational catheter (mL)	Day of index ablation procedure	Total fluid infused through the investigational catheter (mL)

Trial Locations

Locations (28)

Grandview Medical Center; 🇺🇸 Birmingham, Alabama, United States

University Of Alabama; 🇺🇸 Birmingham, Alabama, United States

Iowa Heart Center; 🇺🇸 West Des Moines, Iowa, United States

Southlake Regional Health Center; 🇨🇦 Newmarket, Ontario, Canada

Montreal Heart Institute; 🇨🇦 Montreal, Quebec, Canada

Clinique Pasteur; 🇫🇷 Toulouse, France

Leipzig Heart Institute GmbH; 🇩🇪 Leipzig, Germany

Centro Cardiologico Monzino; 🇮🇹 Milan, Milano, Italy

Ospedale dell'Angelo; 🇮🇹 Venezia, Italy

Keck School Of Medicine; 🇺🇸 Los Angeles, California, United States

Advent Health, Florida Hospital Orlando; 🇺🇸 Orlando, Florida, United States

Kansas City Heart Rhythm Institute; 🇺🇸 Overland Park, Kansas, United States

Massachusetts General Hospital; 🇺🇸 Boston, Massachusetts, United States

Jackson Heart Clinic; 🇺🇸 Jackson, Mississippi, United States

North Mississippi Medical Center; 🇺🇸 Tupelo, Mississippi, United States

Icahn School of Medicine at Mount Sinai; 🇺🇸 New York, New York, United States

Montefiore Medical Center; 🇺🇸 New York, New York, United States

Trident Medical Center; 🇺🇸 Charleston, South Carolina, United States

Medical University Of South Carolina; 🇺🇸 Charleston, South Carolina, United States

Texas Cardiac Arrhythmia Research Foundation; 🇺🇸 Austin, Texas, United States

Houston Methodist Hospital; 🇺🇸 Houston, Texas, United States

Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ); 🇨🇦 Québec, Quebec, Canada

Na Homolce; 🇨🇿 Praha, Prague, Czechia

St Ann's University Hospital; 🇨🇿 Brno, Czechia

Institut Klinicke a Experimentalni Mediciny (IKEM); 🇨🇿 Praha, Czechia

Clinique du Tonkin; 🇫🇷 Villeurbanne, Lyon, France

CHRU Nancy; 🇫🇷 Nancy, France

Clinique Saint Pierre; 🇫🇷 Perpignan, France