Detection of atrial electromechanical dysfunction in obesity

Obesity is associated with atrial fibrillation and is known as an independent risk factor. The aim of our study was to investigate if there was any association between the body mass index and atrial electromechanical intervals in obese and non-obese patients.

Seventy patients were enrolled in the study. Body mass index (BMI), functional capacity, and fasting blood sugar were evaluated; then, these patients were divided into two groups, patients who had a BMI ≥ 30 were known as obese (35 patients) and those who had a BMI < 30 were known as non-obese patients. All patients were evaluated by transthoracic echocardiography. LA volumes were measured by the discs method in the apical four-chamber view. LA active and passive emptying volumes and fraction were calculated. Using TDI, atrial electromechanical coupling (PA) was measured from the lateral mitral annulus (PA lateral), septal mitral annulus (PA septum), and right ventricular tricuspid annulus (PA tricuspid).

LA diameter was significantly higher in obese patients (P = 0.021). LA passive emptying volume and fraction were significantly decreased in obese patients (P = 0.038 and P = 0.011). LA active emptying volume and fraction were significantly increased in obese patients (P = 0.001 and P = 0.001). Left intraatrial and interatrial electromechanical delay were significantly higher in obese patients (18.9 ± 3.8 vs 11.9 ± 2.0, P < 0.001 and 29.5 ± 4.1 vs 17.9 ± 2.5, P < 0.001). Also interatrial electromechanical delay correlated positively with BMI.

This study revealed that delayed atrial electromechanical interval and impaired LA mechanical functions were related to BMI in obese-patients. These findings may be an early sign of subclinical atrial dysfunction and arrhythmias in obese patients.