Objective The objective of this study was to investigate the clinical application of 4D AUTO LAQ technology in evaluating left atrial functions in patients with Essential hypertension (EH). Methods Ninety-nine EH patients treated in our hospital from September 2020 to September 2021 were enrolled. According to the diagnostic criteria of left ventricular mass index (LVMI)

the case group was divided into non-left ventricular hypertrophy (NLVH) group (n=53) and left ventricular hypertrophy (LVH) group (n=46). Healthy physical examiners were enrolled as the control group (n=48). Conventional echocardiography parameters including left atrial systole diameter (LADs)

left ventricular mass (LVM)

left ventricular ejection fraction (LVEF)

early diastolic transmitral inflow velocity (E)

late diastolic transmitral inflow velocity (A)

peak velocity of the transmitral annulus early diastole（e''）

E/e''

etc; 4D AUTO LAQ technique was used to measure the volume and strain parameters of left atrial

including left atrial minimum volume (LAVmin)

left atrial volume before A wave (LAVpreA)

left atrial maximum volume (LAVmax)

left atrial maximum volume index (LAVI)

left atrial reservoir phase longitudinal strain (LASr)

left atrial reservoir phase circumferential strain (LASr-c)

left atrial ductal phase longitudinal strain (LAScd)

left atrial ductal phase circumferential strain (LAScd-c)

left atrial systolic phase longitudinal strain (LASct) and left atrial systolic phase circumferential strain (LASct-c). The differences of conventional ultrasound parameters and 4D AUTO LAQ technical parameters among the three groups were compared. Draw the ROC curve and calculate the area under the curve of each 4D AUTO LAQ technical parameter. Results The conventional echocardiography showed that there was no significant difference in LADs and LVEF between NLVH group and control group (P>0.05). Compared with the control group

LVEF decreased and LADs increased in LVH group (P<0.05); LADs of the LVH group was higher than that in NLVH group (P<0.05)

and the difference in the LVEF group was not statistically significant (P>0.05). The 4D AUTO LAQ technical parameters showed that compared with the control group

LASr and LAScd were decreased in NLVH group(P<0.05)

and there was no significant difference in LAEF (P>0.05); LASr

LAScd

LASct

LASr-c

LASct-c and LAEF decreased in LVH group (P<0.05). Compared with NLVH group

LASr

LASct

LASr-c

LASct-c and LAEF decreased in LVH group (P<0.05). ROC curve analysis showed that LASr was more sensitive to evaluate left atrial function than other left atrial strain parameters in patients with EH(Comparison between control group and NLVH group

AUC was 0.813; Comparison between control group and LVH group

AUC was 0.918; Comparison between NLVH group and LVH group

AUC was 0.790). Conclusion Changes in left atrial strain in patients with EH occur before left ventricular systolic function. Among the left atrial strain parameters

LASr and LAScd are the most effective in evaluating left atrial function in patients with EH. 4D AUTO LAQ technology can be used to obtain the early left atrial volume and strain parameters in hypertensive patients to assess left atrial function.