Determinants of left intra-atrial electromechanical delay as evaluated by tissue Doppler imaging in candidates for coronary artery bypass graft surgery

Predictive value of interatrial block on electrocardiogram among obese patients undergoing atrial fibrillation ablation

BACKGROUND

Determine a predictive value of interatrial block (IAB) on atrial fibrillation (AF) ablation outcomes in obese patients.

METHODS

Medical records were retrospectively reviewed for 205 consecutive patients with body mass indices (BMI) ≥ 30 kg/m2 who underwent initial AF ablation. Evidence of partial IAB defined as P-wave duration (PWD) ≥ 120 ms and advanced IAB with PWD ≥ 120 ms and biphasic or negative P-wave in inferior leads was examined from sinus electrocardiograms (ECGs) within 1-year pre-ablation. The primary outcome was recurrent atrial arrhythmia after 3-month blanking period post-ablation.

RESULTS

The mean BMI was 36.9 ± 5.7 kg/m2. Partial IAB and advanced IAB were observed in 155 (75.61%) and 42 (20.49%) patients, respectively. During the median follow-up of 1.35 (interquartile range 0.74, 2.74) years, 115 (56.1%) patients had recurrent atrial arrhythmias. In multivariable analysis adjusting for age, gender, persistent AF, use of antiarrhythmic drugs (AADs), left atrial volume index (LAVI), partial IAB, and advanced IAB were independent predictors of recurrent arrhythmia with hazard ratio (HR) of 2.80 (95% confidence interval [CI] 1.47-6.05; p = 0.001) and HR 1.79 (95% CI 1.11-2.82; p = 0.017), respectively. The results were similar in a subgroup analysis of patients who had no severe left atrial enlargement and a subgroup analysis of patients who were not on AADs.

CONCLUSIONS

IAB is highly prevalent in patients with obesity and AF. Partial IAB, defined as PWD ≥ 120 ms, and advanced IAB with evidence of biphasic P-wave in inferior leads were independently associated with increased risk of recurrent arrhythmia after AF ablation. Its predictive value is independent of other traditional risk factors, LAVI, or use of AADs.

Effects of obesity on left atrial phasic functions in patients with chronic ischemic heart disease and preserved left ventricular ejection fraction without recent myocardial infarction: a two-dimensional speckle-tracking echocardiography study

PURPOSE

Left atrial (LA) phasic functions in various subgroups of subjects with obesity are differently impaired, suggesting that obesity may have diverse effects in dissimilar subgroups of subjects with obesity. We aimed to compare the effects of obesity on LA phasic functions in patients suffering from chronic ischemic heart disease with a preserved left ventricular ejection fraction and without a recent myocardial infarction.

METHODS

In our cross-sectional study, 145 consecutive candidates for isolated coronary artery bypass graft (CABG) surgery were divided according to the presence of obesity into 2 groups: obese (36 patients) and nonobese (103 patients), and LA phasic functions were evaluated by two-dimensional speckle-tracking echocardiography (2D STE).

RESULTS

The longitudinal strain rate during the reservoir phase (3.0 ± 0.7 s-1 vs 2.7 ± 0.6 s-1; P = 0.032), longitudinal strain during the contraction phase (19.2 ± 4.7% vs 17.2 ± 4.1%; P = 0.022), and the longitudinal strain rate during the contraction phase (4.4 ± 1.2 s-1 vs 3.9 ± 1.2 s-1; P = 0.036) decreased in the obese group compared with the nonobese group. The other longitudinal 2D STE-derived markers of the LA phasic functions were not different between the 2 groups.

CONCLUSIONS

Among patients suffering from chronic ischemic heart disease with a preserved left ventricular ejection fraction and without a recent myocardial infarction, LA reservoir and contraction functions as measured by 2D STE were impaired in patients with obesity compared with those without it.

Effects of weight loss after bariatric surgery on atrial electromechanical delay in obese subjects

Background: The authors investigated the relationship between weight loss after sleeve gastrectomy and change in atrial electromechanical delay values. Methods: A total of 41 patients were included. The primary end point was any effect of total weight loss on atrial electromechanical delay parameters. Results: The mean loss of body weight was 25.50 ± 11.07 kg. There was a significant correlation between mean body weight change and change in interatrial and left intra-atrial electromechanical delays (Pearson's correlation coefficient: 0.575 and 0.871, respectively; p < 0.001). Only change in body weight was significantly related to change in interatrial electromechanical delay (regression coefficient: 0.707; p < 0.01). Conclusion: In this study, a significant relationship was found between amount of body weight loss and decrease in atrial electromechanical values.

Determinants of the Volumetric Markers of Left Atrial Contraction Function in Coronary Artery Disease: A Cross-sectional Study

BACKGROUND

A body of research advocates the prognostic role and usefulness of the volumetric markers of left atrial (LA) phasic functions in the diagnosis of LA dysfunction. We aimed to determine the independent determinants of the volumetric markers of LA contraction function in candidates for coronary artery bypass graft (CABG) surgery.

METHODS

This cross-sectional study enrolled 516 candidates for CABG. The biplane maximal, minimal, and pre-P volumes of the LA were measured with two-dimensional echocardiography, and LA active emptying fraction was calculated. The standardized correlation coefficient for the correlation between each factor and LA active emptying fraction was calculated by using univariate and backward multivariable regression analyses.

RESULTS

The multivariable regression analysis demonstrated that the heart rate (β = 0.15; p = 0.001), S (β = 0.09; p = 0.036), E/e′ ratio (β = −0.11; p = 0.014), left ventricle (LV) ejection fraction (β = 0.15; p = 0.001), and LA enlargement (β = −0.19; p < 0.001) were the independent determinants of LA active emptying fraction.

CONCLUSIONS

The independent determinants of LA contraction function were the heart rate, S, LV ejection fraction, LA enlargement, and E/e′ ratio in candidates for CABG surgery.