Coronary artery ectasia is associated with atrial electrical and mechanical dysfunction: an observational study

The aim of our study was to investigate total atrial conduction time and left atrial (LA) mechanical function in patients with isolated coronary artery ectasia (ICAE).

Sixty patients with ICAE without any visible coronary stenosis were enrolled to this cross-sectional observational study. The control group consisted of 40 age- and gender-matched patients. Left atrial mechanical functions were measured by the method of discs in the apical-four chamber echocardiographic view. LA mechanical function parameters were calculated. P wave dispersion was measured on electrocardiography (ECG). The total atrial conduction time (PA-tissue Doppler imaging (TDI) duration) was assessed by measuring the time interval between the beginning of the P wave on the surface ECG and point of the peak A wave on TDI from LA lateral wall just over the mitral annulus. Student t, Mann-Whitney U, Pearson's, and Spearman's correlation analysis and multiple regression analysis were used for statistical analysis.

The clinical and laboratory characteristics were similar in two groups. Both groups were similar in terms of Vmax and LA total emptying volume (29.0 ± 7.3 vs. 31.9 ± 6.5 mL/m², p=0.082 and 19.9 ± 5.1 vs. 20.0 ± 5.2 mL/m², p=0.821). However, LA passive emptying volume and LA passive emptying fraction were significantly decreased with ICAE patients (11.1 ± 3.2 vs. 13.5 ± 3.8 ml/m², p=0.005 and 35.2 ± 7.2 vs. 47.8 ± 9.4 mL/m², p<0.001). But LA active emptying volume and LA active emptying fraction were significantly increased in ICAE patients (9.1 ± 2.6 vs. 6.4 ± 3.0 mL/m², p<0.001 and 45.3 ± 8.1 vs. 40.7 ± 6.7 mL/m², p=0.002). PA-TDI duration was measured significantly higher in patients with ICAE than control group (131.8 ± 5.7 vs. 114.4 ± 9.1 ms, p<0.001). Multiple linear regression analyses showed that ectatic segment number was an independent factor of PA-TDI duration (β=0.581, 95% CI=4.046-6.295, p<0.001).

Our study demonstrated presence of LA electrical and mechanical dysfunction in patients with ICAE. LA dysfunction may be associated with cardiac pathologies as arrhythmias, decrease in cardiac output and congestive failure.