Left atrial late gadolinium enhancement (LGE) on cardiac MRI was significantly correlated with atrial stiffness index in patients with atrial fibrillation (R=0.59, p<0.001).
Observational (n=67)
In patients with atrial fibrillation, left atrial fibrosis assessed by CMR LGE is a strong marker of atrial stiffness, whereas left atrial pressure correlates poorly with strain but modestly with maximum LA volume.
Effect estimate: R=0.59
p-value: p=<0.001
Aims: A relationship between left atrial strain and pressure has been demonstrated in many studies, but not in an atrial fibrillation (AF) cohort. In this work, we hypothesized that elevated left atrial (LA) tissue fibrosis might mediate and confound the LA strain vs. pressure relationship, resulting instead in a relationship between LA fibrosis and stiffness index (mean pressure/LA reservoir strain). Methods and Results: Sixty-seven patients with AF underwent a standard cardiac MR exam including long-axis cine views (2 and 4-ch) and a free-breathing high resolution three-dimensional late gadolinium enhancement (LGE) of the atrium (N=41), within 30 days prior to AF ablation, at which procedure invasive mean left atrial pressure (LAP) was measured. LV and LA Volumes, EF, and comprehensive analysis of LA strains (strain and strain rates and strain timings during the atrial reservoir, conduit and active phases) were measured and LA fibrosis content (LGE (ml)) was assessed from 3D LGE volumes. LA LGE was well correlated to atrial stiffness index (LA mean pressure/LA reservoir strain) overall (R=0.59, p<0.001), and among patient subgroups. Pressure was only correlated to maximal LA volume (R=0.32) and the time to peak reservoir strain rate (R=0.32), among all functional measurements. LA reservoir strain was strongly correlated with LAEF (R=0.95, p<0.001) and LA minimum volume (r=0.82, p<0.001). Conclusion: In our AF cohort, pressure is correlated to maximum LA volume and time to peak reservoir strain. LA LGE is a strong marker of stiffness.
Lamy et al. (Tue,) conducted a observational in Atrial fibrillation (n=67). Cardiac MRI with 3D late gadolinium enhancement (LGE) and invasive left atrial pressure measurement was evaluated on Correlation between left atrial late gadolinium enhancement (LGE) and atrial stiffness index (R=0.59, p=<0.001). Left atrial late gadolinium enhancement (LGE) on cardiac MRI was significantly correlated with atrial stiffness index in patients with atrial fibrillation (R=0.59, p<0.001).