Left Atrial Reservoir Strain To Identify Advanced Atrial Cardiomyopathy in Patients With Atrial Fibrillation.

Background

Left atrial reservoir strain (LASr) is a novel marker of left atrial (LA) function. We hypothesized that LASr can be used to identify atrial cardiomyopathy in patients with atrial fibrillation (AF).

Objective

To evaluate the association between LASr and invasive and non-invasive markers of atrial cardiomyopathy in AF patients.

Methods

We prospectively recruited patients with symptomatic paroxysmal or persistent AF and preserved left ventricular (LV) ejection fraction scheduled for catheter ablation. Resting transthoracic echocardiography was performed focusing on the left atrium (LA). Participants were dichotomised into two groups: reduced LASr (<20%) and preserved LASr (≥20%). Markers of LA cardiomyopathy were compared between these two groups; invasive markers included mean LA pressure, mean LA voltage and LA compliance whilst non-invasive markers included LA volumes and NT-pro BNP.

Results

A total of 91 patients were enrolled. Patients with reduced LASr (n=31) were older (69.4±8.9 vs 59.6±11.3 years, p<0.001), and more commonly female (45.2 vs 18.3%, p=0.007). Reduced LASr correlated with lower LA compliance (0.28±0.16 vs 0.42±0.25mm/mmHg, p<0.001), higher LA pressure (14.8±3.81 vs 13.1±4.46mmHg, p=0.031), and lower LA voltage (1.65±1.35 vs 3.12±1.57mV, p<0.01). On non-invasive assessment, reduced LASr was also associated with higher NT-proBNP levels (479 [200-1073] vs 121 [58-256] pg/ml p<0.001) and larger LA volumes (38.5±11.5 vs 32.6±7.7 mL/m2, p<0.001).

Conclusion

In patients with symptomatic AF, reduced LASr is associated with a more advanced atrial cardiomyopathy involving hemodynamic, mechanical and electrical atrial dyfsfunction. LASr may therefore provide a useful non-invasive marker of atrial cardiomyopathy in AF.