Echocardiographic evaluation of left atrial function and non-invasive hemodynamic parameters in hemodialysis patients

Introduction: Cardiovascular diseases are very common in hemodialysis patients and are the leading cause of mortality in this patient group. Many physiopathological factors that occur due to chronic kidney disease cause left atrial remodeling, leading to impaired left atrial mechanics and an increase in left atrial diameter. Changes in left atrial structure can be evaluated by tissue doppler echocardiography and pulse wave echocardiography. In recent years, strain evaluation by speckle tracking echocardiography has gained importance in determining subclinical myocardial dysfunction. Materials and Methods: Between November 2017 and March 2020, 39 hemodialysis (HD) patients with no known major cardiovascular disease undergoing hemodialysis in the Hemodialysis Unit of the Department of Nephrology, Ankara University Faculty of Medicine were included in our study. Demographic characteristics, comorbidities, medications, HD duration (months), HD-related follow-up data, types of previous renal replacement therapy (RRT) and laboratory test results at the time of echocardiography were collected. Early transmitral peak velocity (E), late transmitral peak velocity (A), deseleration time were measured by pulsed wave doppler echocardiography and tissue doppler echocardiography one hour before and after HD, e' (early annular tissue doppler velocity), a' (late annular tissue doppler velocity) and s' (systolic annular velocity) from the mitral medial and lateral annulus and their ratios E/A, E/e (mean) and ePCWP (estimated pulmonary capillary wedge pressure) were calculated with "nagueh formula 1. 24 x E/e'(mean) +1.9" to calculate ePCWP. Two-dimensional speckle tracking echocardiography was used to measure left atrial strain and global longitudinal strain (GLS) in the reservoir (LASr), conduction (LAS-cd) and contraction (LAS-ct) phases and left atrial maximum volume (LAV-max), left atrial minimum volume (LAV-min), left atrial volume before atrial contraction (LAV-PreA) and total left atrial emptying fraction (LAEF) were calculated. Results: The mean age of the patients was 53.9 ± 13.9 years; 20 (51.3%) were female and 19 (48.7%) were male. All patients were undergoing HD with AVF. The mean duration of HD was 65.3 (4-300) months. Four patients (10.3%) were on HD 2 days a week and 35 patients (89.7%) were on HD 3 days a week. The mean UF volume was 2.7 ± 0.8 liters and the mean UF percentage was 3.9 ± 1.3% during the HD session in which echocardiography was performed. In the evaluation of the patients before and after HD by conventional two-dimensional echocardiography and tissue Doppler echocardiography; mitral E, mitral A, mitral lateral s', mitral lateral e' and ePCWP values were significantly decreased.( p:<0.001, p:0.011, p:0.029, p:0.023 and p:0. 005 ) The changes in mitral E/A and mitral E/e' values of the patients after HD were not statistically significant. In two-dimensional BTE, LAV-max, LAV-min and LAV-preA values of the patients decreased significantly after HD (p:0. 001, p:0.014, p:0.033).The GLS value of the patients significantly deteriorated after HD (16.7 ± 3.11% before HD, 14.2 ± 3.5% after HD, p: 0.000). The decrease in LASr, LAS-cd and LAS-ct values of the patients after HD was not statistically significant. (Before HD; LASr: 22.95 ± 9.42%, LAS-cd: -12.71 ± 6.84%, LAS-ct: -11.24 ± 7.57% after HD; LASr: 20.58 ± 8.77%, LAS-cd: -10.87 ± 6.68%, LAS-ct: -10.32 ± 5.36) The decrease in LAEF values after HD was not significant.(LAEF before HD: 50.03±12.30% LAEF after HD: 49.39±10.97%) Conclusion: While the parameters evaluated by tissue doppler and pulse wave echocardiography changed after HD, strain parameters did not change in all three phases of left atrial strain. More studies evaluating the effect of volume differences on left atrial strain are needed. Keywords: Hemodialysis, left atrium, strain, echocardiography