Multiparametric MRI Assessment of Atrial Heart Disease as a Predictor of Atrial Fibrillation After Myocardial Revascularization Surgery

N/ANot Yet RecruitingNCT04657835

Centre Hospitalier Universitaire de Saint Etienne100 enrolled

Overview

Postoperative atrial fibrillation (POAF) occurs in 20-40% of patients undergoing coronary artery bypass grafting (CABG) and is a marker of atrial vulnerability. It is strongly associated with AF recurrence, stroke, and cardiovascular mortality. It presents risk factors with atrial heart disease. The latter refers to all structural, electrical, and mechanical alterations of the atrium that create a substrate conducive to AF. Multiparametric cardiac MRI is currently the most comprehensive test for assessing atrial heart disease, thanks to its structural and functional analysis (atrial fibrosis, atrial strain, intracavitary 4D flow). However, to date, no prospective study has evaluated these parameters as predictors of AF recurrence after CAP. At the same time, an implantable Holter monitor will be used to enable detailed and continuous detection of recurrence episodes, overcoming the limitations of conventional monitoring strategies. By combining multiparametric imaging, histological analysis, and continuous monitoring for the first time, this study proposes a paradigm shift in the assessment of postoperative AF: moving from a descriptive and ad hoc approach to a mechanistic, integrative, and predictive approach.

Study Type

INTERVENTIONAL

Allocation

Purpose

OTHER

Masking

NONE

Enrollment

100

Conditions

Postoperative Atrial Fibrillation

4D cardiac MRI with gadoteric acidDEVICE

4D cardiac MRI with gadoteric acid injection will be performed prior the surgery, according to a standardized technical protocol.

Blood sampleBIOLOGICAL

Peripheral venous blood sample (1 x 6 ml EDTA tube): taken during preoperative assessment to measure inflammatory biomarkers (CRP, IL-1, TNF-α).

Implantable Loop Recorder (ILR)DEVICE

Implantation of a Holter monitor (Implantable Loop Recorder) prior to surgery, performed preoperatively under local anesthesia. The ILR will enable continuous recording of the heart rhythm for 12 months with automatic data transmission via remote monitoring. The minimally invasive procedure will be performed by an experienced cardiologist under the usual safety conditions.

Right atrial biopsyPROCEDURE

During the surgical procedure (coronary artery bypass grafting), a right atrial biopsy will be performed using a brief, low-risk procedure on a small tissue sample. The sample will be analyzed using Masson's trichrome staining to assess atrial fibrosis.

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age ≥ 18 years * Indication for surgical myocardial revascularization by isolated coronary artery bypass grafting, to be performed in the cardiac surgery department of Saint-Étienne University Hospital. * Patient affiliated with or entitled to social security coverage * Patient who has received informed information about the study and has co-signed, with the investigator, a consent form to participate in the study Exclusion Criteria: * Contraindication related to cardiac MRI * Contraindication related to ILR implantation * Documented history of atrial fibrillation * Concomitant indication for valve surgery or other associated cardiac intervention * Inability to understand French * Patient refusal to participate in the study and/or inability to express consent or sign the informed consent form * Patient subject to legal protection measures

Outcomes

Primary Outcomes

Evaluate the predictive value of atrial heart disease characterized by multiparametric MRI (late enhancement fibrosis, atrial strain, and exploratory 4D flow parameters) for the recurrence of atrial fibrillation documented by Implantable Loop Recorder.

Recurrence of atrial fibrillation, defined as an episode lasting ≥ 30 seconds documented by the Implantable Loop Recorder (ILR) implanted preoperatively and recorded during the 12-month follow-up period.

Time frame: through study completion, an average of 12 months

Secondary Outcomes

Evaluate the link between atrial heart disease characterized by MRI (fibrosis, strain, 4D flow) and the occurrence of postoperative atrial fibrillation (POAF) during the first week following coronary artery bypass grafting.

POAF will be defined as an episode of AF ≥ 30 seconds, detected by the preoperatively implanted ILR and recorded during the first postoperative week.

Time frame: through the first postoperative week

Correlate MRI parameters of atrial remodeling with histological assessment of fibrosis on intraoperative atrial biopsy

Percentage of histological fibrosis. Analysis of atrial fibrosis using Masson's trichrome staining on intraoperative atrial biopsy (normal threshold ≤ 10%). The objective is to establish a correlation between histological data and MRI parameters.

Time frame: through the first postoperative week

Exploring the value of atrial hemodynamic parameters obtained by 4D flow MRI (vorticity, intra-atrial velocities) as predictive markers of atrial fibrillation

measurement of intra-auricular blood flow using 4D-flow MRI, including velocities (cm/s), flow volumes (mL/s or mL), and vorticity indices (s-¹)

Time frame: Before the surgery

To study the association between serum inflammatory biomarkers (CRP, IL-1, TNF-α) and Atrial Fibrillation recurrence.

Preoperative measurement of pro-inflammatory cytokines (IL-1, TNF-α, CRP).

Time frame: before the surgery

Determine the impact of atrial fibrillation recurrence documented by ILR on the occurrence of major cardiovascular events

Number of ischemic strokes, hospitalizations for heart failure, cardiovascular deaths occurring within one year of surgery, and all-cause deaths.