| Objective:To investigate the affect of different blood pressure circadian rhythm on cardiac structure and function in hypertensive patients.Method:One hundred and eighty hypertensive patients whose blood pressure reached the target value were divided into dipper group (n=30), non-dipper group (n=99), and reverse dipper group (n=51) according to the blood pressure circadian rhythm. Clinical data,24-hour ambulatory blood pressure monitoring, and heart structure and function examination were obtained from the three groups and the relationship between them was analyzed as well.Result:l.The comparison of the general clinical situation:Mean systolic blood and diastolic blood pressure, the classification of blood pressure, and the use of antihypertensive drugs showed no statistical difference among the three groups.2. Characteristics of echocardiography changes of cardiac structure and function.2.1Related parameters of left ventricular structure difference between three groups have no statistical significance.2.2The comparison of cardiac function related parameters.2.2.1Left ventricular ejection fraction had no statistically significant difference among the three groups.2.2.2Mitral valve flow spectrum:E/A, DT, IVRT there was no significant difference between the three groups; Pulmonary vein blood flow spectrum and the left ventricular flow propagation velocity there was no statistically significant difference between the three groups.2.2.3Tissue doppler and its derivative parameters:From dipper to non-dipper and reverse-dipper group, the ratio of peak mitral E wave to peak mitral annulus E’wave (E/E’) increased in order (8.1±2.4,8.6±2.5,9.6±3.2,P＜0.05),and it was higher in reverse-dipper group than that in dipper and non-dipper groups (P＜0.05).2.2.4Left atrial size:Left atrial volume index (LAVi) in reverse-dipper group and non-dipper group was greater than that in dipper group (43.8±11.8ml/m2,40.7±9.8ml/m2,36.6±8.5ml/m2,P＜0.05or P＜0.01).3.Heart function influence factors analysis:E/E’ was correlated with nighttime systolic blood pressure and age positively while with nocturnal blood pressure decline rate negatively, of which BPR was the independent predictor of E/E’; Pulse pressure, hypertension course and nocturnal blood pressure decline rate were independently correlated with LAVi.Conclusion:1.Abnormal blood pressure circadian rhythm adds damage to the heart function of hypertensive patients, with diastolic dysfunction as the key impairment.2. Reverse-dipper than non-dipper blood pressure pattern deteriorated diastolic function more severely.3.Tissue doppler parameter are more sensitive than traditional diastolic function indexes.4.Attache great importance to ambulatory blood pressure monitoring and echocardiography is of great significance to research hypertension target-organ damage.5.Clinicians should not only focus on control of daytime blood pressure, but also to strengthen the regulation of blood pressure at night, strive to blood pressure circadian rhythms tend to be normal, benefit the patients as possible. |
