Assessment of the ability of the CHADS-VASc scoring system to grade left atrial function by 2D speckle-tracking echocardiography.

BACKGROUND

The CHADS-VASc scoring system is correlated with left atrial (LA) reservoir function in patients with atrial fibrillation (AF) rhythm or paroxysmal AF. We assessed the ability of CHADS-VASc to grade LA function in patients with sinus rhythm who were candidates for coronary artery bypass grafting (CABG).

METHODS

This cross-sectional study recruited 340 consecutive candidates for CABG and categorized them according to their CHADS-VASc scores as mild-, moderate-, and high-risk score groups with 34 (10%), 83 (24%), and 223 (66%) patients, respectively. LA function was evaluated via 2D speckle-tracking echocardiography in terms of global longitudinal strain and strain rate during the reservoir, conduit, and contraction phases. In-hospital mortality, postoperative AF, prolonged intensive care unit (ICU) stay, and prolonged mechanical ventilation were assessed.

RESULTS

LA strain and strain rate during the reservoir phase was statistically significantly lower in the high-risk score group than the low- and moderate-risk score groups (27.8 ± 6.9% vs 31.0 ± 5.0% vs 29.8 ± 6.1%, respectively; P = 0.004 and 2.6 ± 0.7 s vs 2.9 ± 0.6 s vs 2.9 ± 0.6 s, correspondingly; P = 0.009) and regarding LA strain and strain rate during the conduit phase (9.7 [7.1-12.5]% vs 12.9 [9.4-15.1]% vs 11.5 [9.1-13.8]%, correspondingly; P < 0.001 and 2.1 [1.6-2.7] s vs 2.8 [2.4-3.6] s vs 2.6 [2.2-3.0] s, respectively; P < 0.001). In addition, LA strain rate during the conduit phase was lower in the moderate-risk score group than the low-risk score group. After adjustments for possible confounders, these differences remained statistically significant. The risk of postoperative AF and prolonged ICU stay was highest in the high-risk score group (relative risk = 9.67 (1.31-71.43) and 8.05 (1.08-60.16), respectively; P = 0.026 and P = 0.042, respectively).

CONCLUSIONS

LA reservoir and conduit functions decreased in the high-risk score group, which was accompanied by an increased risk of postoperative AF and prolonged ICU stay.