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MAX - SHOCK Clinical Trial

Comparison of Maximum Energy Shocks From Two Defibrillator Vendors MAX - SHOCK- A Randomized Controlled Clinical Trial

Status
Recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06556667
Acronym
MAX-SHOCK
Enrollment
376
Registered
2024-08-16
Start date
2025-03-31
Completion date
2027-09-01
Last updated
2026-02-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Atrial Fibrillation, Cardioversion

Keywords

defibrillator

Brief summary

Can Electrical Cardioversion (ECV) for AF be improved. It is the preferred method to restore sinus rhythm in patients with AF in whom a rhythm-control strategy is pursued. Hypothesis: ECV success rates will be greater with a biphasic defibrillator with maximum energy of 360J (® Physio-Control) compared to a biphasic defibrillator with maximum energy of 200J (® Zoll)

Detailed description

Published estimates of ECV success using modern biphasic defibrillators vary considerably but most are limited by small sample sizes. Our pre-intervention ECV success rate of 91.8% was stable over \>2.5 years and is comparable to a previous study from our institute11 and to recent estimates from moderately sized studies using contemporary technology. For instance, the Euro Heart Survey on AF reported an ECV success rate of 91% in 424 patients2 and the Biphasic Energy Selection for Transthoracic cardioversion of Atrial Fibrillation (BEST AF) trial reported 89% success in 380 patients.3 The variability in starting shock energy and shock energy escalation observed at our centre prior to implementing the OAFCP is also consistent with reported practices elsewhere. A recent survey of 57 European centres found that nearly two-thirds of hospitals started with a 100 J biphasic shock for AF whereas the remaining third started with 200 J.1 Considerable differences in electrode placement were also reported in this survey with 58.7% of centres using an anterolateral position and the remainder using an anteroposterior approach.1Our investigators and others have previously shown that physicians seldom apply sufficient force even when prompted to do so and even when using handheld paddles.10,16,17 ECV practices at our institute prior to implementing the OAFCP were therefore likely representative of those at most centres.

Interventions

DEVICEbiphasic defibrillator with maximum energy of 200J (® Zoll)

Cardioversion

DEVICEbiphasic defibrillator with maximum energy of 360J (® Physio-Control)

Cardioversion

Sponsors

Ottawa Heart Institute Research Corporation
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Subject)

Masking description

participants will not know which defibrillator was used during their cardioversion.

Intervention model description

two arms will be compared using the Chi squared test

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Patients age \> 18 years. * Persistent atrial fibrillation. * Scheduled for elective cardioversion at UOHI * Patient is within the circle of care of UOHI Electrophysiology staff

Exclusion criteria

* Known left-atrial appendage thrombus. * Contraindication to appropriate anticoagulation. * Patient is included in another randomized clinical trial. * Patient does not meet all of the above listed inclusion criteria.

Design outcomes

Primary

MeasureTime frameDescription
ECV success2 secondsECV success defined as \>\_2 consecutive sinus beats, or captured atrial-paced beats in patients with implanted cardiac devices, after shock delivery

Secondary

MeasureTime frameDescription
First shock success2 secondsCardioversion is successful without crossover
sustained success4 hourssustained sinus or atrial paced rhythm documented on 12-lead electrocardiogram

Countries

Canada

Contacts

CONTACTTammy Knight
tknight@ottawaheart.ca613-696-7000
CONTACTDavid Birnie
dbirnie@ottawaheart.ca613-696-7000
PRINCIPAL_INVESTIGATORMehrdad Golian

Ottawa Heart Institute Research Corporation

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026