The Relationship Between Frontal QRS-T Angle And Circadian Rhythm Of Blood Pressure In Essential Hypertenson

Objective : To explore the relationship between abnormal circadian rhythm of blood pressure and frontal QRS-T angle in patients with essential hypertension.Methods: The clinical data of 161 hospitalized patients with essential hypertension(EH)from January 2021 to October 2022 were retrospectively collected.According to the circadian rhythm of blood pressure measured by 24 h ambulatory blood pressure monitoring(ABPM),EH patients were divided into two groups:normal circadian rhythm group(n = 61)(dipper blood pressure,nocturnal blood pressure drop rate 10～20%),abnormal circadian rhythm group(n = 100)(non-dipper blood pressure,nocturnal blood pressure drop rate 0～10%;Reverse dipper type,nocturnal blood pressure drop rate less than 0%;super-dipper type,nocturnal blood pressure drop rate> 20%).The frontal QRS-T angle was obtained from 12-lead ECG and compared between groups.Univariate multivariate Logistic regression analysis was performed to explore the independent predictors of abnormal circadian rhythm of blood pressure.Receiver operating characteristic(ROC)analysis was performed to obtain the cutoff value of frontal QRS-T angle for abnormal circadian rhythm of blood pressure.Results:1.There were no significant differences in age,sex,BMI,smoking and history of drinking,medication history for hypertension,hematology analysis and biochemical indicators,and echocardiography between the two groups(P>0.05).The frontal QRS-T angle [20.50(9.25,42.00)vs 14.00(6.00,24.50),P=0.002)]in the abnormal circadian rhythm group was larger than that in the normal circadian rhythm group.The mean n SBP(P=0.013),mean n DBP(P=0.025)and night mean arterial pressure(P=0.013)in the abnormal circadian rhythm group were higher than those in the normal circadian rhythm group.24 h SSD(P=0.012)and 24 h SBP-CV(P=0.006)in the abnormal circadian rhythm group were lower than in the normal circadian rhythm group,and the MBPS in the normal circadian rhythm group was higher than in the abnormal circadian rhythm group(P = 0.024).In the abnormal circadian rhythm group,the number of patients with hypertension for less than 5 years(P=0.018)was less than that in the normal circadian rhythm group,and the number of patients with hypertension for 5 years ≤ 10 years(P=0.043)was greater than that in the normal group.2.Correlation analysis showed that frontal QRS-T angle had no correlation with ambulatory blood pressure and LVMI.Univariate multivariate logistic regression analysis showed that drinking history(OR= 0.411,95%CI:0.171～0.993,P =0.048)and frontal QRS-T angle(OR= 1.043,95%CI : 1.018～1.068,P <0.001)were independent predictors of abnormal circadian rhythm of blood pressure in hypertensive patients.3.The cutoff value of frontal QRS-T angle for abnormal circadian rhythm of blood pressure in patients with essential hypertension was 37°(AUC:0.645;95% CI:0.561～0.769;P=0.02),with a sensitivity of 31% and a specificity of 100%.Conclusions:1.Compared with the normal circadian rhythm group,the patients with abnormal circadian rhythm of blood pressure had larger frontal QRS-T angle.2.The frontal QRS-T angle is an independent predictor of abnormal circadian rhythm of blood pressure in essential hypertension,and can be used as a simple classification mark of abnormal circadian rhythm of blood pressure in essential hypertension patients.