Correlation Of Left Atrial Strain With Left Ventricular Diastolic Dysfunction In Patients With Normal Left Ventricular Ejection Fraction

Background:Echocardiography is important to evaluate left ventricular diastolic dysfunction(LVDD),however,current echocardiographic parameters show moderate sensitivity in evaluating LVDD,with the presence and severity of LVDD failing to be determined for a significant proportion of patients.Left ventricular end-diastolic pressure measured by cardiac catheterization was gold reference to diagnose LVDD.We sought to explore the correlation between left atrial(LA)strain and LVDD in patients with normal left ventricular ejection fraction(LVEF).Methods:Between June 2018 and November 2019,207 consecutive individuals with LVEF≥50%who underwent standard transthoracic echocardiography,and left atrial strain were obtained by speckle tracking echocardiography on the Echo PAC work station(GE Healthcare).The left ventricular diastolic function was evaluated by 2016ASE/EACVI guidelines.Cardiac catheterization was performed in 55 patients for clinical reasons that required evaluation for coronary artery disease.Left ventricular end-diastolic pressure(LVEDP)was measured by invasive left-heart catherization,A LVEDP value>16mmHg was defined as elevated LV filling pressure.Logistic regression analysis was used to determine the predictor for elevated LV filling pressure,and receiver operating characteristics(ROC)curves were created to compare the performance of multiple variables in determining increased LVEDP.Bland-Altman analysis was used to determine the accuracy of LVEDP predicted by LASr.In the general population,contingency tables of normal left ventricular diastolic function and left ventricular diastolic dysfunction by both LASr and 2016 ASE/EACVI guidelines were created to depict inter-technique agreement,which was tested by kappa statistics.ROC curves were created to evaluate the accuracy of categorization of LVDD evaluated by LASr.Results:1.In 55 patients underwent invasive cardiac catheterization,left atrial strain was independent predictor for LVEDP>16mmHg.LVEDP negatively correlated with LASr(R=0.662,p<0.001),LASct(R=0.575,p<0.001)and LAScd(R=0.456,p<0.001),but not with E/e’ and left atrial volume index(LAVi).2.The area under the curve(AUC)for LASr is 0.914(cutoff value is 26.7%,sensitivity is 90%,specificity is 82.9%),which can predict LVEDP better than LASct and LAScd.Bland-Altman analysis confirmed this closed agreement between LVEDP estimated by LASr and invasive LVEDP.3.In the total 207 individuals,75 patients were defined as normal left ventricular diastolic function,and 132 patients were defined as LVDD.LASr is less than 26.7%in 121 patients(92%),which shows better diagnostic accuracy than traditional echocardiographic parameters.4.Substantial inter-technique agreement was found between normal left ventricular diastolic function and left ventricular diastolic dysfunction evaluated by both LASr and 2016 ASE/EACVI guidelines(kappa=0.722,p<0.001).5.Left atrial strain categorization of LVDD:With regard to LA strain,the cut-off value of>26.51%to identify normal diastolic function with 78.4%sensitivity,and 93.8%specificity.The cut-off value of>21.28%to differentiate grade 1 diastolic dysfunction or normal diastolic function from grades 2 and 3 diastolic dysfunction with 71.3%sensitivity,and 83.0%specificity.The LA strain threshold of>12.11%to separate grade 3 LVDD performed the best of all LA strain thresholds,with sensitivity,specificity,and accuracy upward of 90%.Conclusions:1.In patients with normal LV ejection fraction,left atrial strain presents good correlation with LVEDP,LASr is superior to LASct and LAScd to predict LVEDP,it can predict LVEDP>16mmHg with high accuracy.2.The area under the curve(AUC)for LASr is 0.914(cutoff value is 26.7%,sensitivity is 90%,specificity is 82.9%),which demonstrated better agreement with the invasive reference than LAScd and LASct.3.Left atrial strain categorize left ventricular diastolic dysfunction with high accuracy.