Atrial fibrillation fingerprinting; spotting bio‐electrical markers to early recognize atrial fibrillation by the use of a bottom‐up approach (AFFIP): Rationale and design

Figures

• 

  FIGURE 1. Concept of the atrial fibrillation fingerprinting (AFFIP) study. The AFFIP study hypothesizes that every patient has a unique biological and electrical signal profile that is influenced by age, gender and heart disease. Intra‐operative high‐resolution epicardial mapping is performed to identify the patient‐specific electrical profile, whereas the biological profile is assessed by evaluating proteostasis levels in blood samples and atrial appendage tissue samples. Derailment of protein homeostasis can lead to structural remodeling, favoring inhomogeneous conduction and progression of atrial fibrillation (AF). We aim to develop a novel diagnostic tool, the bio‐electrical AF Fingerprint, to predict onset and early progression of AF

• 

  FIGURE 2. Time course of the atrial fibrillation fingerprinting (AFFIP) study. A baseline blood sample (red bar) is obtained from all patients 1 day prior to surgery. During surgery, the study procedure (blue bar, epicardial mapping) is performed, followed by post‐operative continuous rhythm monitoring (orange bar). Patients are consulted by phone at 6 months, 12 months, and yearly up to 5 years after surgery for detection of late post‐operative atrial fibrillation (AF) (green bars)

• 

  FIGURE 3. Epicardial mapping to retrieve unipolar atrial electrograms. With the use of a 192 electrode arrays, the left atrium (LA), right atrium (RA), pulmonary vein (PV) area, and Bachmann's bundle (BB) are mapped following this predefined mapping scheme. Unipolar atrial electrograms are collected during sinus rhythm (SR), pacing maneuvers (P), and (electrically induced) atrial fibrillation (AF). Morphology of atrial potentials are subdivided into four categories: single potentials (one deflection), short double potentials (two deflections less than 15 ms apart), long double potentials (two deflections 15 ms or more apart), and complex fractionated potentials (three or more deflections). ICV, inferior caval vein; LAA, left atrial appendage; PVL, left pulmonary vein area; PVR, right pulmonary vein area; RAA, right atrial appendage; SCV, superior caval vein

• 

  FIGURE 4. Construction of the atrial fibrillation fingerprint (AFFIP). The left panel shows an example of an activation map during electrically induced atrial fibrillation (AF) of the left pulmonary vein area in a patient undergoing coronary artery bypass grafting without a history of AF. Isochrones are drawn at 5 ms, areas of conduction block (Δ local activation time [LAT] ≥ 12 ms) are indicated by black bars and the origin of peripheral waves by gray dots. The arrows indicate main activation direction. The corresponding fractionation map is displayed in the right panel and shows the different types of atrial potential morphologies: single potentials (SP, one deflection), short double potentials (sDP, two deflections less than 15 ms apart), long double potentials (lDP, two deflections 15 ms or more apart) and complex fractionated potentials (CFP, three or more deflections). The maps are used to determine the incidence of for example, fractionation and conduction block