Abstract 17532: How to Assess the Best Left Atrial Function by Speckle Tracking: Recommendations for a Standard Method
2D speckle-tracking echocardiography (STE) is a novel, feasible technique for the assessment of longitudinal myocardial left atrial (LA) function. Normal ranges, and also cutoff values to diagnose LA dysfunction with different diseases have been reported. However, 2 different methods, based on P-wave and R-wave as the reference point for generation of strain curves, have been used. Therefore, we compared these 2 methods, in order to define which one provides the most correct assessment of all LA functions.
Methods: 20 normal subjects (46±14 yrs, 11 men) with adequate 2D images in 4C view were evaluated for LA function by STE. We used 2 different methodologies, P-wave and R-wave as a reference point, for the evaluation of LA strain, strain rate, and derived times. Active LA function was assessed from negative global strain at atrial contraction (GSA-), time from P to peak negative strain (TGSA-), and late diastolic strain rate (GSRL); passive function from positive global strain at AVC (GSA1+) and at MVO (GSA2+), and time from R-wave to both peaks (TGSA1 and TGSA2), late positive global strain (GSAL), and also from early negative diastolic global strain rate (GSRE); reservoir function from the sum of GSA- and GSA1+ (SUMGSA), positive global strain rate at the beginning of LV systole (GSR+), and time from P to peak (TGSR+).
Results: Active LA function (GSA-) was significantly lower, whereas passive and reservoir functions were significantly higher (GSA1+, GSA2+, GSAL, SUMGSA) with R-wave method (both p<0.001; see table). There were no differences between methods regarding all derived times and strain rate indices.
Conclusions: The 2 methods used to assess LA functions by STE do not provide similar results. The R-wave method essentially ignores active function, and overestimates late conduit function by comparison with the P-wave method, and therefore, we suggest that using P-wave as a reference point for generation of strain curves might estimate correctly all LA functions.
- © 2011 by American Heart Association, Inc.