Clinical Evaluation of the Blazer® Open-Irrigated Catheter for Treatment of Type 1 Atrial Flutter (BLOCk-CTI)

• ClinicalTrials.gov Identifier: NCT01253200
• Recruitment Status: Completed
• First Posted: December 3, 2010
• Results First Posted: February 15, 2018
• Last Update Posted: March 19, 2018
• Sponsor: Boston Scientific Corporation
• Information provided by (Responsible Party): Boston Scientific Corporation

Tracking Information

• First Submitted Date: November 21, 2010
• First Posted Date: December 3, 2010
• Results First Submitted Date: March 9, 2017
• Results First Posted Date: February 15, 2018
• Last Update Posted Date: March 19, 2018
• Study Start Date: January 2011
• Actual Primary Completion Date: September 2013 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: January 18, 2018)

• Procedure-related Complication-free Rate [ Time Frame: 7 days post-procedure ]
  A procedure-related complication is defined as an adverse event that results in death, a life-threatening complication, or a persistent or significant disability/incapacity or required intervention to prevent a permanent impairment of a body function or damage to a body structure. All adverse events related to the investigational or control devices or ablation procedure will be considered procedure-related events.
• Acute Success Rate [ Time Frame: 30 minutes after the last radiofrequency application in the cavo-tricuspid isthmus ]
  Acute success is defined as demonstration of bidirectional cavo-tricuspid isthmus block (ie, lack of electrophysiological conduction through the isthmus) 30 minutes after the last radiofrequency application in the cavo-tricuspid isthmus with the investigational or control catheter only.

Original Primary Outcome Measures (submitted: December 2, 2010)

• Primary Safety [ Time Frame: 7 days ]
  Procedure-related complication-free rate through 7 days post-procedure.
• Primary Effectiveness [ Time Frame: 30 minutes ]
  Bidirectional block of the cavo-tricuspid isthmus at least 30 minutes following the last RF application in the isthmus.

Current Secondary Outcome Measures (submitted: January 18, 2018)

• Chronic Success Rate: All Treated Patients [ Time Frame: 3 months post-procedure ]
  Chronic success is defined as freedom from recurrence of type 1 atrial flutter at 3-months post-procedure for all treated patients.
• Chronic Success Rate: Acute Success Patients [ Time Frame: 3-months post-procedure ]
  Chronic success is defined as demonstration of acute success and freedom from recurrence of type 1 atrial flutter at 3-months post-procedure. Only randomized patients with acute procedural success will be included in this endpoint.

Original Secondary Outcome Measures (submitted: December 2, 2010)

Secondary Effectiveness [ Time Frame: 3 months ]

Freedom from recurrence of type 1 atrial flutter at 3-months post-procedure.

• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: Clinical Evaluation of the Blazer® Open-Irrigated Catheter for Treatment of Type 1 Atrial Flutter
• Official Title: Clinical Evaluation of the Blazer® Open-Irrigated Radiofrequency Ablation Catheter for the Treatment of Type 1 Atrial Flutter
• Brief Summary: The purpose of the BLOCk-CTI study is to evaluate the safety and effectiveness of the Blazer® Open-Irrigated Ablation Catheter for the treatment of sustained or recurrent type 1 atrial flutter. This study will compare outcomes in patients treated with the Blazer® Open-Irrigated Ablation Catheter to outcomes in patients treated with open-irrigated radiofrequency ablation catheters that have received FDA market approval for the treatment of type 1 atrial flutter.
• Detailed Description: The BLOCk-CTI study is a prospective, multicenter, single blind, 1:1 randomized study. The study is designed to demonstrate that the safety and effectiveness of the Blazer® Open-Irrigated Ablation Catheter are non-inferior to the safety and effectiveness of the control catheters. In this study, the control catheters are open-irrigated radiofrequency ablation catheters that have received FDA market approval for the treatment of type 1 atrial flutter. (Biosense Webster ThermoCool® ablation catheters (NaviStar™, EZ Steer, or SF) or St. Jude Medical ablation catheters (Therapy™ Cool Path™ or Safire BLU™).
• Study Type: Interventional
• Study Phase: Not Applicable

Study Design

Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Masking Description:

Subject was not told by investigator if device used was Investigational or Control. The subject could ask the investigator at end of study at 3 months if they wanted to know which device was used.

Primary Purpose: Treatment

• Condition: Atrial Flutter

Intervention

• Device: Blazer® Open-Irrigated Ablation Catheter
  Blazer® Open-Irrigated Ablation Catheter
• Device: Control Catheter
  Open-irrigated radiofrequency ablation catheters that have received FDA market approval for the treatment of type 1 atrial flutter
  Other Name: ThermoCool, NaviStar, EZ Steer, SF, Cool Path, Safire BLU

Study Arms

• Experimental: Blazer® Open-Irrigated Ablation Catheter
  Patients treated with the Blazer® Open-Irrigated Ablation Catheter
  Intervention: Device: Blazer® Open-Irrigated Ablation Catheter
• Active Comparator: Control Catheter
  Patients treated with an open-irrigated radiofrequency ablation catheter that has received FDA market approval for the treatment of type 1 atrial flutter( Biosense Webster ThermoCool® ablation catheters (NaviStar™, EZ Steer, or SF) or St. Jude Medical ablation catheters (Therapy™ Cool Path™ or Safire BLU™),
  Intervention: Device: Control Catheter

• Publications *: Not Provided

Recruitment Information

• Recruitment Status: Completed
• Actual Enrollment (submitted: April 11, 2014): 302
• Original Estimated Enrollment (submitted: December 2, 2010): 240
• Actual Study Completion Date: January 2014
• Actual Primary Completion Date: September 2013 (Final data collection date for primary outcome measure)

Eligibility Criteria

Inclusion Criteria:

• At least 1 documented episode of type 1 atrial flutter in the 180 days (6 months) preceding enrollment documented by 12-lead ECG, Holter monitor, rhythm strip, or transtelephonic monitor
• Patients are clinically indicated for catheter ablation
• Patients receiving oral anti-arrhythmic drug therapy (class I or class III) for a tachyarrhythmia other than type 1 atrial flutter must be controlled on the anti-arrhythmic drug for a minimum of 30 days prior to enrollment. If type 1 atrial flutter was documented prior to the development of other tachyarrhythmias, this 30-day period is not required.
• Age 18 or above, or of legal age to give informed consent specific to state and national law
• Patients are competent and willing to provide written informed consent to participate in the study and agree to comply with follow-up visits and evaluation

Exclusion Criteria:

• Any prior right atrial cavo-tricuspid isthmus ablation or any cardiac ablation for non-atrial flutter arrhythmias within 90 days prior to enrollment
• Cardiac surgery within 90 days prior to enrollment
• Myocardial infarction within 60 days prior to enrollment
• Current unstable angina
• Patients who cannot have anti-arrhythmic drugs (class I and class III) prescribed for the treatment of type 1 atrial flutter stopped on the day of the procedure
• Patients regularly prescribed amiodarone within the 120 days (4 months) prior to enrollment
• Documented atrial or ventricular tumors, clots, thrombus, or have a known clotting disorder within 90 days prior to enrollment
• Implantation of permanent leads of an implantable device in or through the right atrium within 90 days prior to enrollment
• Direct remedial cause of atrial flutter (e.g. thyroid disease, pericarditis, pulmonary embolic disease)
• Atypical or scar-based flutter
• Patients with New York Heart Association Class III at the time of enrollment or New York Heart Association Class IV heart failure within 90 days prior to enrollment
• Patients with an ejection fraction less than 30% within 90 days prior to enrollment
• Clinically significant structural heart disease (including tricuspid valve regurgitation, tricuspid valve stenosis, tricuspid valve replacement, Ebstein's anomaly, or other congenital heart disease) that would preclude catheter introduction and placement, as determined by the Investigator
• Any cerebral ischemic event (including transient ischemic attacks) within 180 days prior to enrollment
• Contraindication to anticoagulation therapy based upon published guidelines
• Creatinine greater than 2.5 mg/dl or creatinine clearance less than 30 mL/min within 90 days prior to enrollment
• Any other significant uncontrolled or unstable medical condition (e.g. sepsis, acute metabolic illness)
• Enrolled in any concurrent study without BSC written approval
• Women who are pregnant or plan to become pregnant within the course of their participation in the investigation
• Life expectancy less than or equal to 2 years (730 days) per physician opinion

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 18 Years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: United States

Administrative Information

• NCT Number: NCT01253200
• Other Study ID Numbers: BLOCk-CTI
• Has Data Monitoring Committee: No

U.S. FDA-regulated Product

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: Yes

IPD Sharing Statement

• Plan to Share IPD: No

• Current Responsible Party: Boston Scientific Corporation
• Original Responsible Party: CRV Clinical Director, Boston Scientific Corporation
• Current Study Sponsor: Boston Scientific Corporation
• Original Study Sponsor: Same as current
• Collaborators: Not Provided

Investigators

• Principal Investigator: Tom McElderry, MD; University of Alabama at Birmingham

• PRS Account: Boston Scientific Corporation
• Verification Date: February 2018