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Trial details imported from

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Registration number
Ethics application status
Date submitted
Date registered
Date last updated

Titles & IDs
Public title
Cologne Cardioversion Study
Scientific title
Randomized Controlled Trial Comparing Internal vs External Cardioversion in ICD Patients
Secondary ID [1] 0 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Atrial Arrhythmia 0 0
Heart Failure 0 0
Condition category
Condition code
Cardiovascular 0 0 0 0
Coronary heart disease
Cardiovascular 0 0 0 0
Other cardiovascular diseases

Study type
Description of intervention(s) / exposure
Treatment: Devices - Internal Electrocardioversion
Treatment: Devices - External Electrocardioversion

Active Comparator: External Electrocardioversion - Cardioversion with an external cardioverter-defibrillator with a step-up energy protocol (100, 150, 200, 360 J biphasic) in antero-posterior orientation, maintaining a > 8 cm distance between shock electrodes and device and complying with a "cool-down" phase of 2 minute between shocks, if more than one shock is required.

Experimental: Internal Electrocardioversion - Cardioversion via the implanted ICD with a maximum energy synchronized shock (41 J, with a RV -> SVC+can shock orientation in pts with SVC leads). After 1 ineffective internal shock, the patient will be counted as internal CV failure and cardioverted externally, following the same protocol as the external CV group.

Treatment: Devices: Internal Electrocardioversion
Cardioversion by internal shock application via the implanted ICD

Treatment: Devices: External Electrocardioversion
Cardioversion by external shock application via a cardioverter/defibrillator.

Intervention code [1] 0 0
Treatment: Devices
Comparator / control treatment
Control group

Primary outcome [1] 0 0
Combined Safety Endpoint - Any one of the following as assessed by device interrogation:
a rise in threshold (at constant duration) of >0.5V
exit block of one of the pacing leads
loss of programming of the device
a rise in shock impedance by 50% as compared to prior to CV
a drop in battery voltage of =0.2V within 2 weeks
Timepoint [1] 0 0
2 weeks after CV
Primary outcome [2] 0 0
Efficacy Endpoint: restoration of sinus rhythm - Assessed by ECG, within the first seconds after DC shock application (via external CV or internal shock)
- Restoration of sinus rhythm
In all patients a single p wave after cardioversion counts as a successful shock. Early recurrence of AF does not count as shock failure. In case of early recurrence of AF/AT, the successful shock may be performed once more, according to randomization. Adjunctive antiarrhythmic drug administration is left to the physician's discretion
Timepoint [2] 0 0
Within 1 minute after CV
Secondary outcome [1] 0 0
Induction of ventricular fibrillation - Inadvertent induction of VF during CV, assessed by 3 or 5 lead ECG monitoring during the procedure.
Timepoint [1] 0 0
during CV procedure
Secondary outcome [2] 0 0
Lead parameter indicators of impairment - Assessed by device interrogation within 15 minutes after CV and at follow-up after 2 weeks:
Lead impedance > 1000 Ohm
Lead impedance doubled
Ventricular lead sensing < 2mV
Ventricular lead sensing halved, compared to prior to CV
Atrial lead sensing < 1mV
Atrial lead sensing halved, compared to prior to CV
Timepoint [2] 0 0
within 15 minutes after CV and 2 weeks after CV
Secondary outcome [3] 0 0
Troponin - Comparison of Troponin T levels prior to and 3h after cardioversion
Timepoint [3] 0 0
3h after CV
Secondary outcome [4] 0 0
Recurrence at follow-up - Rhythm at follow-up assessed by ECG and device interrogation. Atrial fibrillation and atrial flutter or atrial tachycardia will be counted as recurrence.
Timepoint [4] 0 0
at follow-up 2 weeks after CV

Key inclusion criteria
- Age = 18 years

- Informed, written consent

- Atrial arrhythmia with indication for CV

- Status post ICD implantation, including CRT-D
Minimum age
18 Years
Maximum age
99 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
- Age < 18 years

- Patients under guardianship or with mental disorders / disabilities

- ICD implantation < 4 weeks prior to CV

- ICD lead implantation < 4 weeks prior to CV

- Battery in EOL, ERM or ERI, ERT

- Indications of compromised leads (Impedance <200 or >2000 Ohm, Pacing threshold
>5V/0.4ms), RV Sensing <4mV or RA sensing <0,1mV)

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 0 0
Royal Adelaide Hospital - Adelaide
Recruitment postcode(s) [1] 0 0
- Adelaide
Recruitment outside Australia
Country [1] 0 0
State/province [1] 0 0
Country [2] 0 0
State/province [2] 0 0
Country [3] 0 0
State/province [3] 0 0
Bad Oeynhausen
Country [4] 0 0
State/province [4] 0 0
Country [5] 0 0
State/province [5] 0 0
Country [6] 0 0
State/province [6] 0 0
Country [7] 0 0
State/province [7] 0 0
Country [8] 0 0
State/province [8] 0 0
Country [9] 0 0
State/province [9] 0 0
Country [10] 0 0
State/province [10] 0 0

Funding & Sponsors
Primary sponsor type
Universitätsklinikum Köln
Other collaborator category [1] 0 0
Commercial sector/Industry
Name [1] 0 0
Address [1] 0 0
Country [1] 0 0

Ethics approval
Ethics application status

Brief summary
Implantation of internal defibrillators, capable of monitoring the heart and shocking life
threatening arrhythmias back to normal rhythm, for patients with severe heart failure
increases the probability of survival. Arrhythmias of the atria of the heart are common in
these patients. Administering a direct current electrical shock under anesthesia
(cardioversion) is the method of choice to reestablish normal sinus rhythm in this instance.
Safety and efficacy of external electrical cardioversion (CV) in patients with ICDs was
demonstrated in several studies. Safety of internal cardioversion (shocking the heart back
into normal rhythm via the implanted defibrillator) was described in several smaller trials.

Performing external instead of internal cardioversion in patients with implanted ICDs is more
feasible for most hospitals, as CV can be performed without a programming computer and an
additional specialist present, e.g. on the intensive care ward, and device interrogation can
be done after CV at the remote ICD/pacemaker clinic.

No scientific data on safety and efficacy endpoints comparing internal vs external CV is
currently available. The aim of the study is to compare external vs internal electrical
cardioversion for atrial arrhythmias and establish a safety and efficacy profile for external
and internal cardioversion in large cohort of ICD patients.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 0 0
Daniel Steven, Prof. Dr.
Address 0 0
University Hospital Cologne
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for scientific queries

Summary results
Other publications