The Ottawa AF Cardioversion Protocol

Developing a Standardized Atrial Fibrillation Cardioversion Protocol

Atrial fibrillation is an abnormal heart rhythm in which the top chambers of the heart (the atrial chambers) beat very fast. Electrical cardioversion is a technique to convert heart rhythm from AF to normal rhythm. The technique sends out a brief electric shock to the heart through electrodes (paddles or skin patches) applied to the outside of the chest wall. The shock resets the heart rhythm back to its normal pattern.

This technique is practiced at many hospitals, including the Heart Institute, and is not experimental. However no detailed national or international guidelines exist to assist physicians in performing cardioversion. Physicians use a variety of methods. Electrical cardioversion does not always restore normal rhythm. Adjusting the electrical energy dose, changing the electrode position and applying pressure to the electrodes may improve the success rate.

This study will look at the safety and efficacy of a protocol (step by step method) for electrical cardioversion. The protocol prescribes the electrical energy dose, the electrode position and the application of pressure to the electrodes the physician will use. The individual elements of the protocol (energy dose, electrode position and pressure application) are often used by physician in clinical practice but not necessarily in the step by step order.

The purpose of this study is to get all doctors to follow a standard protocol 'the Ottawa AF cardioversion protocol'. We think that using this protocol will improve overall cardioversion success rates. The results of this study may change usual practice in Canada and in other countries.

All supplies, equipment and medications used in the protocol cardioversion are approved by Health Canada.

We estimate that 389 participants from the University of Ottawa Heart Institute will be enrolled in the study over the next 2 years. The results will be compared with a group of previous patients.

Study Overview

• Status: Completed
• Conditions: Atrial Fibrillation
• Intervention / Treatment: Device: Lifepak 20E Defibrillator, Licence No: 61944

Detailed Description

Study design:

All eligible and consenting patients will undergo elective electrical cardioversion for atrial fibrillation (AF) using the Ottawa AF protocol.The fact that the physician follows the protocol makes this experimental. Aside from following the protocol, subjects will receive standard care before, during and after the procedure. Outcomes of the procedure and clinical features know to affect cardioversion efficacy will be collected. These will be compared to a group of 500 previous patients who underwent elective electrical cardioversion for AF at the Heart Institute.

Methodology:

The Ottawa AF protocol prescribes the electrical energy dose, the electrode position and the application of pressure to the electrodes the physician will use. The individual elements of the protocol (energy dose, electrode position and pressure application) are often used by physician in clinical practice but not necessarily in the step by step order.

The Ottawa AF protocol prescribes the following:

• the starting energy dose (200 J) and electrode placement (anterior-posterior)
• the second electrode placement (anterior-lateral) if the first shock is not successful
• addition of pressure to electrodes if second shock is not successful
• step up of energy dose (360 J) along with pressure to electrodes if third shock is not successful
• optional further steps at physician's choice if fourth shock is not successful

• Study Type: Interventional
• Enrollment (Actual): 389
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Ottawa, Ontario, Canada, K1Y 4W7
      • University of Ottawa Heart Institution

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Documented atrial fibrillation within last 12 months
• On continuous systemic oral anticoagulation for 28 days prior to the day of cardioversion or must have undergone a recent (< 48 hrs) trans-esophageal echocardiogram prior to the day of cardioversion
• Able to provide informed consent

Exclusion Criteria:

• Presence of intracardiac thrombus
• Pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Ottawa AF Cardioversion; elective electrical cardioversion for atrial fibrillation (AF) using the Ottawa AF protocol	Device: Lifepak 20E Defibrillator, Licence No: 61944; Intervention will be carried out using Health Canada approved devices for electrical cardioversion, following the steps pre-specified in the Ottawa AF Protocol. Ottawa AF Cardioversion; Other Names: -HEARTSTART XL, Licence No: 24413.; -Kendall 1010P Multi-function Defibrillation Electrodes, Licence No: 21857

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Last shock efficacy	Last shock efficacy defined as success ( two or more beats of sinus rhythm) or failure.	immediately after cardioversion

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adverse Events	adverse events related to cardioversion	participants will be followed for the duration of hospital stay for elective cardioversion, an expected average of 2 hours.

Collaborators and Investigators

• Sponsor: David Birnie

Publications and helpful links

General Publications

• Ramirez FD, Sadek MM, Boileau I, Cleland M, Nery PB, Nair GM, Redpath CJ, Green MS, Davis DR, Charron K, Henne J, Zakutney T, Beanlands RSB, Hibbert B, Wells GA, Birnie DH. Evaluation of a novel cardioversion intervention for atrial fibrillation: the Ottawa AF cardioversion protocol. Europace. 2019 May 1;21(5):708-715. doi: 10.1093/europace/euy285.

Study record dates

Study Major Dates

• Study Start: August 1, 2015
• Primary Completion (Actual): December 1, 2017
• Study Completion (Actual): April 1, 2018

Study Registration Dates

• First Submitted: July 11, 2014
• First Submitted That Met QC Criteria: July 16, 2014
• First Posted (Estimate): July 17, 2014

Study Record Updates

• Last Update Posted (Actual): October 2, 2019
• Last Update Submitted That Met QC Criteria: September 30, 2019
• Last Verified: September 1, 2019

More Information

Terms related to this study

• Keywords: atrial fibrillation; cardioversion; electrical cardioversion; cardioversion protocol
• Additional Relevant MeSH Terms: Pathologic Processes; Heart Diseases; Cardiovascular Diseases; Arrhythmias, Cardiac; Atrial Fibrillation
• Other Study ID Numbers: 20140415; Form ID 2788 (Other Identifier: Ottawa Health Science Network Research Ethics Board)