Evaluation Of Left Ventricular Systolic Synchronicity In Patients With Hypertension By Real-time Three-dimensional Echocardiography

Estimiting cardiac function is one of the most important contents of echocardiography. Cardiac function evaluation is an important guidance in diagnosing,therapeutic effect and prognotic assessment of cardiovascular disease. Because of noninvasive and high repeatability, echocardiography plays an important role in diagnosing disease of cardiovascular system. Hypertension is an angiocardiopathy which can lead to heart failure finally. Heart failure include diastolic heart failure and systolic heart failure ,there are fundamental difference between their treatment. That's why most of the ultrasonic investigation are qualitative analysis of left ventricular function in patients with hypertension. There were reports that intraleft ventricular systolic dyssynchrony frequently coexisted with diastolic abnormalities in hypertensive patients with a normal LVEF, and myocardial asynchronization index are considered to be correlate with left ventricular systolic function. So,analyzing the left ventricular myocardial synchronization will supply new information in hypertensive therapy.For the past few years, with the development of new technique(eg:TVI,TTI, TSI et al), tissue doppler imaging has become the most important method in eveluating synchronism. Their characteristic in common are based on measuring tissue motion velocity by doppler , many of these parameters are influenced by doppler techenique itself ,which is angle dependency,single sampling tabulate restriction,can't compare left ventricular synchronism more than six segments meanwhile.Real-time three-dimensional echocardiography is a new technique in clinical application.with the development of analysis software,it overcomes the deficency of two-dimentional ultrasound, can display 17 segment volume-time curve and time-excursion parameter index,and the"Bull-eyes"reflect the sequence of every left ventricular segment reaching minimal systolic volume time, and the diversity of excursion.make it possible to compare all segments of the left ventricular synchronism simultaneously. The computing method dependent on the shape of left ventricle,not influneced by the angle.To observe whether left ventricular systolic dyssynchrony exist in hypertensive patients with diastolic dysfunction, investigate the value of timing-excursion parametric imaging ,we apply real-time three-dimensional echocardiography to detect the left ventricular systolic function and synchronism of 26 hypertensive patients with diastolic dysfunction (group A) and 26 subjects with normal left ventricular function(group B).The consequence displays as follows: the 17 segment volume-time curves of group A have ill-defined appearances, comparing with group B; the time to minimal systolic volume is irregular. there are differences among Tmsv 16-SD,Tmsv 12-SD,Tmsv 16- Dif Tmsv 12-Dif heart rate correction value of group A and group B,expecially Tmsv 16-SD,Tmsv 16- Dif and Tmsv 12- Dif'heart rate correction value(p<0.01), indicating that group A has bad synchronism;the"Bull-eyes"shows the time to minimal systolic volume is irregular,and the excurtion is different,compared with group B, Excursion-Avg, Excursion-SD,Excursion-Max is increase and Excursion-Min is decrease obviously in group A(p<0.05). indicating that group A has bad synchronism ,demonstrate that time-excursion parameter can reflect left ventricular synchronism.while the EDV showed no significant different in group A compared with group B. indicating that intramyocardial systolic asynchronia appears before global left ventricular systolic function changed in early stage patients with hypertension.We get conclusion that real-time three-dimensional echocar- diography"Full volume"imaging technique can discover abnorma- lity of left ventricular myocardial synchronization in early stage patients with hypertension,and estimates the phase accurately. Real-time three-dimensional echocardiography time-excursion parameter index is a new method that evaluate left ventricular myocardial synchronization sensitively. The application of new ultrasound technique can assess the cardiac function and left ventricular systolic synchronization in patients with hypertensive heart disease precisely.