AF Substrate Mapping and Guided Ablation

Not Applicable

Completed

Conditions: Persistent Atrial Fibrillation

Interventions: Device: Substrate+mCPVA
Device: mCPVA

Registration Number: NCT02571218

Lead Sponsor: Abbott Medical Devices

Brief Summary: In this study, the investigators aim to identify and characterize, by means of an EnSite Velocity Research Software, the electrophysiological characteristics of substrates that sustain AF in patients with persistent AF and to test whether ablation of such patient-specific substrates might improve the acute and long-term success of conventional catheter ablation therapy.

Detailed Description: This study is a prospective, single center, randomized, single-blind, controlled, 2-arm parallel group trial in Milan, Italy.

The total duration of the study is expected to be 24 months with \~12 months of enrollment.

Approximately 80 subjects suffering from persistent AF will be randomized in a 1:1 fashion to the following investigation arms:

* Modified circumferential pulmonary vein ablation alone (mCPVA);

* Substrate-targeted ablation guided by AF substrate mapping, followed by completion of modified circumferential pulmonary vein ablation (Substrate+ mCPVA)

* Ablate the areas that have fast and regular electrical activities, starting from the fastest cycle length (defined by Mean CL in the range of 120-250 milliseconds, and SD CL in the range of 1-30 milliseconds

* Ablate the areas that have consistent rotational or focal propagation pattern (defined by conduction velocity vectors)

* Ablate the areas that comprises the slow conduction zone of possible arrhythmia circuits

* If AF terminates during RF ablation, stimulation protocol will be used to examine if AF is re-inducible. If AF sustains or is re-inducible and physician decides to remap, mapping will be performed again for substrate-targeted ablation. If AF is not re-inducible, mCPVA will be completed

Subjects will be followed up at 3, 6, 12 months.

The primary objective of the study is to assess acute and long-term outcome of patient-tailored substrate-targeted ablation (Substrate) plus modified circumferential pulmonary vein ablation (Substrate+mCPVA) versus modified circumferential pulmonary vein ablation alone (mCPVA). The secondary objective of the study is to map and characterize electrophysiological substrates during AF, including regular and fast activities, complex fractionated electrograms, wave front propagation directions, and fibrosis.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 81

Inclusion Criteria

18 - 85 years of age
Persistent AF scheduled to undergo catheter ablation with approved standard indication by ESC/EHRA guidelines
First or second time ablation for persistent AF
Ability to provide written informed consent for study participation and be willing and able to comply with the study evaluations and follow up schedule

Exclusion Criteria

Had two or more previous AF ablation procedures
Secondary AF
Hyperthyroidism
Left ventricular ejection fraction <30%
NYHA functional class IV
Left atrial area > 35 cm2
Uncorrected severe valvular heart disease
Contraindication to anticoagulation
Presence of left atrial thrombus
Recent (<6 Months) myocardial Infarction or unstable angina or coronary artery by-pass
Thoracic surgery for congenital, valvular or aortic disease
History of cerebrovascular accidents
Pregnancy
Significant comorbidities such as cancer, severe renal insufficiency requiring hemodialysis, severe obstructive lung disease, cirrhosis, with a life expectancy less than 2 years

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Substrate+mCPVA	Substrate+mCPVA	Subjects in the Substrate+mCPVA arm will undergo intervention of substrate mapping and substrate-targeted ablation guided by the investigational device, followed by completion of modified circumferential pulmonary vein ablation.
mCPVA	mCPVA	Subjects in the mCPVA arm will undergo intervention called "modified circumferential pulmonary vein ablation", which is considered to be the standard ablation treatment for AF.

Primary Outcome Measures

Name	Time	Method
Long-term Clinical Success Rate	12 months	Freedom from symptomatic AF off antiarrhythmic drug therapy assessed from the end of the 3 months blanking period to 12 months following the ablation procedure, documented by implantable loop recorder (ILR) monitoring or trans-telephonic (TT) ECG monitoring.

Secondary Outcome Measures

Name	Time	Method
Acute Ablation Procedure Outcome	During Ablation	Acute AF termination or significant AF cycle length slowing during RF application in ablation procedure