Identifying Atrial Fibrillation Mechanisms for Personalized Medicine

Figures

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  Figure 1. Patient-focused mechanistic integration to guide personalized atrial fibrillation (AF) management. Clinical presentation alone is suboptimal to guide care, but provides some clues to mechanistic subtypes. Phenotypes can be refined by clinical testing and invasive studies. Ideally, precision phenotypes that integrate mechanisms across multiple biological scales, including biomarkers of omic risk, electrical and structural remodeling, and continuous data streams from wearables, may enable personalized AF therapy. This may be facilitated by tools such as machine learning.

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  Figure 2. Progression of atrial fibrillation from a pulmonary vein–focused disease to a non-pulmonary vein–focused disease. Early AF is initiated by triggers near the pulmonary veins (PVs), that are exacerbated by stretch, inflammation, and other factors. The remodeling of electrical, structural, and neural elements can increasingly be measured in patients. Late AF is characterized by substrates that maintain AF, which are often located outside the pulmonary veins, and likely involve an interplay between electrical and structural components. Bottom right figure is reproduced with permission from Marrouche et al. [39].

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  Figure 3. Several mapping systems for atrial fibrillation are now available to guide ablation. Each modality localized regions, typically 3–5 per patient in both atria, that are sufficiently stable in space, although intermittent in time, such that localized ablation may be effective. FIRM shows focal and rotational sites by activation (and phase) annotation. Electrographic flow indicates vectors (here of a rotational site). Cartofinder shows focal (shown) or rotational sites. STAR mapping shows the earliest sites (in warm colors). RADAR shows composite conduction vectors (rotational site shown). Non-contact charge density maps from a non-contact ultrasound-based catheter (illustrated) indicate rotational (shown), focal, or localized irregular activity patterns. ECGI and body surface mapping may reveal rotational (shown) or focal sites using body surface electrodes in proprietary configurations (illustrated for CardioInsight). See text for details and clinical results.