Intra-Atrial Dyssynchrony Using Cardiac Magnetic Resonance to Quantify Tissue Remodeling in Patients with Atrial Fibrillation

Abstract

Background Recent studies suggest that left atrial (LA) late gadolinium enhancement (LGE) can quantify the underlying tissue remodeling that harbors atrial fibrillation (AF). However, quantification of LA-LGE requires labor-intensive magnetic resonance imaging acquisition and postprocessing at experienced centers. LA intra-atrial dyssynchrony assessment is an emerging imaging technique that predicts AF recurrence after catheter ablation. We hypothesized that 1) LA intra-atrial dyssynchrony is associated with LA-LGE in patients with AF and 2) LA intra-atrial dyssynchrony is greater in patients with persistent AF than in those with paroxysmal AF. Method We conducted a cross-sectional study comparing LA intra-atrial dyssynchrony and LA-LGE in 146 patients with a history of AF (60.0 ± 10.0 years, 30.1% nonparoxysmal AF) who underwent pre-AF ablation cardiac magnetic resonance (CMR) in sinus rhythm. Using tissue-tracking CMR, we measured the LA longitudinal strain in two- and four-chamber views. We defined intra-atrial dyssynchrony as the standard deviation (SD) of the time to peak longitudinal strain (SD-TPS, in %) and the SD of the time to the peak pre-atrial contraction strain corrected by the cycle length (SD-TPS preA , in %). We used the image intensity ratio (IIR) to quantify LA-LGE. Results Intra-atrial dyssynchrony analysis took 5 ± 9 minutes per case. Multivariable analysis showed that LA intra-atrial dyssynchrony was independently associated with LA-LGE. In addition, LA intra-atrial dyssynchrony was significantly greater in patients with persistent AF than those with paroxysmal AF. In contrast, there was no significant difference in LA-LGE between patients with persistent and paroxysmal AF. LA intra-atrial dyssynchrony showed excellent reproducibility and its analysis was less time-consuming (5 ± 9 minutes) than the LA-LGE (60 ± 20 minutes). Conclusion LA Intra-atrial dyssynchrony is a quick and reproducible index that is independently associated with LA-LGE to reflect the underlying tissue remodeling.

Association between interatrial block, left atrial fibrosis, and mechanical dyssynchrony: Electrocardiography‐magnetic resonance imaging correlation

“…In this study cohort, P‐wave measurements by two independent observers did not match in five cases (3.3%), which were finalized by a third independent observer. The inter‐/intra‐reader reproducibility (measured by intraclass correlation coefficient [ICC]) was published before by our group 17,18,15 . LA strain 17 (inter‐reader ICC: 0.96; intra‐reader ICC: 0.92), strain rate 17 (inter‐reader ICC: 0.91; intra‐reader ICC: 0.89), dyssynchrony 18 (inter‐reader ICC: 0.86; intra‐reader ICC: 0.85) and scar quantification by LGE 15 (inter‐reader ICC: 0.97; intra‐reader ICC: 0.98).…”

Quantification of Left Atrial Tissue Remodeling Using Intra-Atrial Dyssynchrony by Cardiac Magnetic Resonance Imaging

“…In this issue, Ciuffo et al 5 advance the understanding of adverse LA remodeling and dysfunction in patients with AF. Using CMR to measure intra-atrial dyssynchrony in sinus rhythm, defined as the standard deviation of the time to the peak longitudinal strain [SD-TPS (%)] and pre-atrial contraction strain [SD-TPS preA (%)] corrected by the cycle length.…”

“…3 , 4 The authors have appropriately acknowledged the potential for selection bias in their non-randomized, retrospective cohort, and this technique requires patients to be in sinus rhythm at the time of CMR imaging. Still, Ciuffo et al 5 have added valuable insights into the understanding of LA remodeling in AF and must be praised for their work, which studied a real-world population and considered the important concern of work-flow for CMR post-processing. Their findings should stimulate more research into the use of intra-atrial dyssynchrony as non-invasive risk stratification for patients with AF, which does not require gadolinium contrast to enhance patient selection for invasive therapies such as catheter-ablation.…”