| Chapter1BackgroundExaminations of fetal heart include structure inspection and cardiac function evaluation. In the diagnosis of fetal heart abnormal structure, we have more mature experiences. However, the evaluation of fetal cardiac function is still difficult.Velocity vector imaging (VVI) could reflect regional and global myocardial mechanics. This paper aims to study fetal myocardial mechanics in normal pregnancy and high-risk pregnancy by VVI, to find out the characteristics and rules. We try to find out more accurate, more sensitive myocardial parameters.Chapter2Evaluation of fetal myocardial mechanics in normal pregnancy using velocity vector imagingObjective:Evaluation of fetal left ventricular and right ventricular systolic and diastolic myocardial mechanics in normal pregnancy。Method:(1) Materials:The study group consisted of158fetuses with gestational age from19weeks to term without structural abnormalities and arrhythmias, in the department of obstetric of Qilu Hospital Shandong University from Dec2008to Dec2011.145cases were analyzed successfully. All the measurement sizes of body developments were keeping with gestational weeks. Gestational age was calculated using the biparietal diameter, head circumference, abdominal circumference, and femur length, and correlated with LMP gestational age. We excluded fetuses of mothers with systemic diseases, such as diabetes, pregnancy-induced hypertension syndrome.(2) Ultrasound machines:Acuson Sequoia512, Acuson Antares ultrasound machines. The types of probes were4C1and6C2.(3) Image collection and processing method:Two-dimensional images of four-chamber view were obtained by a perinatologist with ultrasound machine. Fetal heart was shown at least about1/2-1/3of entire screen. All images, zoomed as large as possible, were stored as digital clip (DICOM), as30-80Hz. The clips were analyzed offline on Axius VVI software. The first step was to definite cardiac cycle by M-mode. R-wave gating was defined at the onset of ventricular systole and the beginning and end of a cardiac cycle, then traced manually the endocardium of the left ventricles. One important step is to check the points along the trace and track the motion in and out, and then edit the trace. The trace was shown on figure1.2or3cardiac cycles which were averaged to obtain VVI data. Parameters used in the software were velocity, strain and strain rate.(4) Designs:①To analyze the distribution of velocity, strain and strain rate among neighbour segments.②To analyze the correlations of global velocity, strain and strain rate with gestational weeks, according to the sc cater plot figure.③All pregnancy women were divided into groups. The contrasts were done in the group and the continuos group.④Myocardial mechanics between left and right ventricular were compered.⑤Inter and intraobserver differences were assessed.Result:(1) In145normal pregnancy fetuses, the distribution of velocity, strain and strain rate among neighbour segments:Whether right or left ventricular, systolic or diastolic period, free wall or ventricular septum, peak velocity decrease from the basal segment to apical segment. The velocity tendency was shown as basal segment> mid segment> apical segment, p <0.05. Both systolic and diastolic, left ventricular myocardial strain and strain rate remained balance in each segment. There was no significant differences between contiguous segments, p>0.05; Right ventricular myocardial free wall strain and strain rate showed decreasing tendency. The differences between some adjacent segments had statistically significant p<0.05. The strain and strain rate of right ventricular septal wall mainly had no difference, p>0.05.(2) The correlations of global velocity, strain and strain rate with gestational weeks:no matter right or left ventricular, systolic or diastolic, myocardial global peak velocity, increases with gestational age, shown moderate correlation. No matter right or left ventricular, systolic or diastolic, there was no correlation between global peak strain, strain rate with gestational age. The global peak strain and strain rate seem stable in the mid and term gestational age.(3) The comparison among the five pregnancy group in global peak velocity, strain and strain rate:the velocities increase from the first group to the fifth group. There was statistically significant between the group and next group, p<0.05. Global peak strain and strain rate were not found statistical difference between the group and next group, p>0.05.(4) The comparison in myocardial mechanics between left and right ventricular:Left ventricular diastolic global peak velocity was less than that of right ventricular, p<0.05; left ventricular diastolic global peak strain rate less than that of right ventricular p<0.05; systolic global peak velocity, strain and strain rate had no statistical differences between left and right ventricular, p>0.05.(5) The repeatability of inter-and intra-observer differences:there were no differences between inter-and intra-observer, p>0.05. The average differences of global peak velocity, strain and strain rate were smaller than segmental velocity, strain and strain rate. The global peak velocity, strain and strain rate had better repeatability.Conclusion:(1) VVI can be an effective method to evaluate myocardial function. Whether right or left ventricular, systolic or diastolic period, free wall or ventricular septum, peak velocity decrease from the basal segment to apical segment.(2) Left ventricular myocardial strain and strain rate remained balance in each segment. Right ventricular myocardial free wall strain and strain rate showed decreasing tendency.(3) No matter right or left ventricular, systolic or diastolic, myocardial global peak velocity increases with gestational age, showing moderate correlation.(4) No matter right or left ventricular, systolic or diastolic, the global peak strain and strain rate seem stable in the mid and term gestational age.(5) The global peak velocity, strain and strain rate had better repeatability than segmental paraments. Chapter3Evaluation of fetal myocardial mechanics in gestational diabetes mellitus pregnancy using velocity vector imagingObjective:Evaluation of fetal left ventricular and right ventricular systolic and diastolic myocardial mechanics in gestational diabetes mellitus (GDM) pregnancy.Method:(1) Materials:The study group consisted of60normal fetuses and36fetuses which of the pregnant women diagnosed with GDM, from December2008to December2011. The gestational age ranged from21to38weeks. All fetuses were singletons without structural abnormalities and arrhythmias, in the department of obstetric of Qilu Hospital Shandong University. We excluded fetuses of mothers with other systemic diseases, such as pregnancy-induced hypertension syndrome. All the women were diagnosed with75g oral glucose tolerance test.(2) Ultrasound machines:Acuson Sequoia512, Acuson Antares ultrasound machines. The types of probes were4C1and6C2.(3) Image collection and processing method:same as chapter2.(4) Designs:The case group was divided into myocardial hypertrophy group and without myocardial hypertrophy group (called as GDM group). According to the case group gestational weeks, the control group was matched. Peak velocity, strain, strain rate and ejection fraction, were used to evaluate fetal myocardial mechanics between the case group and control group.Result:(1) Only2cases were diagnosed as myocardial hypertrophy. The number was less, and we hadn't done statistics analysis.(2) Fetuses without myocardial hypertrophy group (called as GDM group):①Segmental peak velocity, strain and strain rate of GDM group compared with control group:Compered with control group, no matter left or right ventricular, systolic or diastolic, segmental velocity, strain and strain rate of GDM group decreased. There were statistical differences in some of the segments, p<0.05or p<0.01. Some of the segments had not been found statistical differences, p>0.05.②Global peak velocity, strain and strain rate of GDM group compared with control group:Compered with control group, no matter left or right ventricular, systolic or diastolic, global velocity, strain and strain rate of GDM group decreased. All the paraments had statistical differences, p<0.05or p<0.01.③EF value of GDM group compared with control group:There was no statistical difference in EF value between GDM group and control group, p>0.05.(3) The correlations of the paraments with gestational age in GDM and control group:No matter GDM or control group, left or right ventricular, systolic or diastolic, global velocity increased with gestational weeks, showing moderate or low relationship.No matter GDM or control group, left or right ventricular, systolic or diastolic, global strain and strain rate kept stable in gestational weeks.Conclusion:(1) VVI could reflect the fetal myocardial mechanics sensitively in GDM group.(2) The strain and strain rate were more sensitive than EF, and could reveal the myocardial injured even if lack of the myocardial hypertrophy.(3) The strain and strain rate may be useful parameters for assessing the fetal myocardial myocardial mechanics of diabetic mothers. Global strain and strain rate may be more sensitive than segmental strain and strain rate.Chapter4Evaluation of fetal myocardial mechanics in women with pregnancy induced hypertension syndrome using velocity vector imagingObjective:Evaluation of fetal left ventricular and right ventricular systolic and diastolic myocardial mechanics in women with pregnancy induced hypertension syndromeMethod:(1) Materials:The study group consisted of54normal fetuses and36fetuses which of women with pregnancy induced hypertension syndrome, from December2008to December2011. The gestational age ranged from25to36weeks. All fetuses were singletons without structural abnormalities and arrhythmias, in the department of obstetric of Qilu Hospital Shandong University. We excluded fetuses of mothers with other systemic diseases, for example GDM. All the women were diagnosed by clinical doctors.(2) Ultrasound machines:Acuson Sequoia512, Acuson Antares ultrasound machines. The types of probes were4C1and6C2.(3) Image collection and processing method:same as chapter2.(4) Designs:According to gestational weeks of women with pregnancy induced hypertension syndrome, we selected fetuses with the same gestational ages at normal pregnancy women, as control group. The right and left ventricular systolic and diastolic segmental peak velocity, strain, strain rate and global peak velocity, strain, strain rate, were used. The paraments were used to evaluate fetal myocardial mechanics between the case group and control group.Result:(1) Segmental and global paraments comparison between fetuse of women with pregnancy induced hypertension syndrome (called as hypertensive group) and control group:CD Segmental peak velocity, strain and strain rate of hypertensive group compared with control group:Compered with control group, no matter left or right ventricular, systolic or diastolic, segmental velocity, strain and strain rate of hypertensive group decreased. There were statistical differences in some of the segments, p<0.05or p<0.01. Some of the segments had not found statistical differences, p>0.05.(D Global peak velocity, strain and strain rate of hypertensive group compared with control group:Compered with control group, no matter left or right ventricular, systolic or diastolic, global velocity, strain and strain rate of hypertensive group decreased. All the paraments had statistical differences, p<0.05or p<0.01.(2) The correlations of the paraments with gestational age in hypertensive and control group:In hypertensive group, global peak velocity of left ventricular diastolic period increased with gestational weeks, showing low relationship. Global peak velocity of left ventricular systolic had no relationship with gestation. Global peak velocity of right ventricular systolic and diastolic period had no relationship with gestation.In control group, no matter left or right ventricular, systolic or diastolic, global velocity increased in the gestation weeks, showing low relationship.No matter hypertensive or control group, left or right ventricular, systolic or diastolic, global strain and strain rate kept stable in gestational weeks.Conclusion:(1) VVI could reflect the fetal myocardial injured in women with pregnancy induced hypertension syndrome.(2) Global strain and strain rate may be more sensitive than segmental strain an strain rate. Global strain and strain rate may be useful parameters for assessing the fetal myocardial mechanics in women with pregnancy induced hypertension syndrome.Main Innovative Points1. This study was the first to find fetal myocardium strain and strain rate decreased even if lack of the myocardial hypertrophy. It means fetal myocardium systolic and diastolic function injured. The strain and strain rate were more sensitive than EF, and could reveal the myocardial injured.2. This study was the first to find fetal myocardium strain and strain rate decreased in women with pregnancy induced hypertension syndrome. It means fetal myocardium systolic and diastolic function injured.3. The responsibility and sensitivity of global strain and strain rate were better than segmental strain and strain rate. Global strain and strain rate may be the useful paraments in evaluating fetal myocardial mechanics. |
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