Study Of Left Ventricular Systolic Function And Synchronicity In Patients With Non-ischemic Heart Failure

Objective: Previous studies have demonstrated that most of patients withheart failure have marked left ventricular systolic dyssynchrony. Recent datahas provided that patients with non-ischemic heart failure have left ventricularsystolic dyssynchrony. Left ventricular systolic function is considered to be animportant clinical index in evaluation of disease and prognosis. Real-timethree-dimensional echocardiography (RT-3DE) represents a novel method toassess left ventricular systolic synchronicity considering the advantages itself,such as simplification, rapidity, noninvasive measurement and reproducibility.The aim of this study is to evaluate the predictive value of RT-3DE indetermining left ventricular systolic function and synchrony in patients withnon-ischemic heart failure. In the present study, we calculate left ventricularsystolic function and synchrony by RT-3DE and QRS duration by ECG, andassess the relationship between left ventricular systolic synchrony, QRSduration and causes of heart failure.Subjects: Thirty patients aged29-66years old of both sexes withnon-ischemic chronic heart failure and thirty healthy volunteers aged30-68years old of both sexes were enrolled into this study between November2011and November2012. These patients includes dilated cardiomyopathy (n=16),hypertensive heart disease (n=10), peripartum cardiomyopathy (n=2), andalcoholic cardiomyopathy (n=2).Methods: All subjects admitted into this study were divided into twogroups, healthy control groups (n=30) and non-ischemic chronic congestiveheart failure groups (n=30). Weight and height of all subjects were measured.According to body mass index (BMI) formula，BMI was computed. Allpatients with heart failure after hospitalization underwent standard12-leadECG. Based on the QRS width on the ECG, patients with heart failure were divided into the narrow QRS wave (＜120ms) group (n=14) and wide QRSwave (≥120ms) group (n=16). Based on the leading causes of heart failure,the patients with heart failure were divided into two groups, including dilatedcardiomyopathy group (n=16) and hypertensive heart disease (n=10). ASIEMENS sc2000diasonograph with a real-time three-dimensional4zV-1matrix probe was applied at the department of ultrasound of Second Hospitalof Hebei Medical University. Systolic blood pressure (SBP) and diastolicblood pressure (DBP) were measured. Imaging was performed for eachsubject (n=60). All subjects were examined in left-lateral position andconnected with synchronous chest lead ECG. High quality images oftwo-dimensional ultrasonography were first collected using the4v1c matrixprobe. Then4zV-1matrix probe was placed at the apex of the heart, imagingof three-dimensional echocardiography was done after the apical four chamberview image was acquired. The4DLV-analysis software was used to measurecardiac cycle. The software can automatically delineate dynamic3Dendocardial shape, display time-volume curve of16segments of left ventricle,and calculate left ventricular function parameters: LVEDV, LVESV, LVEF andLVSDI16. All images were kept for further analysis. According to the relatedliterature, the SDI of5.12%as a cut-off value, judging whether left ventricularsystolic synchronization.Statistical analysis: All the statistical examinations were performedusing Student’s t-test by SPSS13.0software. All measurement data wererepresented as mean value±SD. All enumeration data were represented aspercentage. Measurement data obeying normality and equal variance wereanalyzed by independent samples t-test. Data failing normality or equalvariance were analyzed by a nonparametric test. The correlation between twovariables was analyzed using Pearson correlation coefficient or Spearmancorrelation analysis. P＜0.05was considered statistically significant.Results: The average age was53.20±8.52years old (30～68years old)in healthy control group (n=30), including17males and13females. Theaverage age was53.60±9.79years old (29～66years old) in non-ischemic chronic heart failure (n=30), including20males and10females. The averageage was54.81±7.27years old in dilated cardiomyopathy group (n=16). Theaverage age was57.40±8.24years old in hypertensive heart disease group(n=10). There are two alcoholic cardiomyopathy patients with heart failure andtwo perinatal cardiomyopathy patients with heart failure. The average age was55.19±9.20years old in16patients in whom the QRS width on the ECG isequal or greater than120ms. The average age was51.79±10.45years old in14patients in whom the QRS width on the ECG is less than120ms. There was nosignificant difference in age, heart rate, SBP, DBP, and BMI between healthycontrol group and non-ischemic chronic heart failure group(P＞0.05). TheQRS duration, LVESV, LVEDV, LVEF, LVSDI of non-ischemic chronic heartfailure group were significantly different compared to that of healthy controlgroup (P＜0.05). The time-volume curve of left ventricle: In healthy controlgroup, the left ventricular myocardial systolic motion curve arranged orderly,each of them synchronously reached the systolic minimum volume, and theminimum volume of every section was similar. However, in the non-ischemicheart failure group, the left ventricular myocardial systolic motion curvearranged disorderly，and the minimum volume of every section was discrepant.The curves were diverse between dilated cardiomyopathy group andhypertensive heart disease group, motion curve of dilated cardiomyopathyarranged more disorderly. Taking LVSDI of5.12%as a cut-off value, wefound that16cases with non-ischemic heart failure were included in wideQRS group, and13cases with non-ischemic heart failure were included innarrow QRS group. No significant difference has been shown in age, heart rate,LVESV, LVEDV, and LVSDI between narrow QRS wave (＜120ms) groupand wide QRS wave (≥120ms) group (P＞0.05). There was not a rectilinearcorrelation between QRS duration and LVSDI (r＝0.107, P＞0.05). There wasno significant difference in age and heart rate between dilated cardiomyopathygroup and hypertensive heart disease group (P＞0.05), however, LVEF of thedilated cardiomyopathy group was significantly lower than that ofhypertensive heart disease group (P＜0.05). LVSDI was significant difference between dilated cardiomyopathy group and hypertensive heart diseasegroup(P＜0.05).Conclusion: Patients with non-ischemic heart failure exist leftventricular systolic dyssynchrony. The QRS duration cannot accurately reflectthe left ventricular systolic function and synchrony of non-ischemic heartfailure patients, even if patients whose QRS duration＜120ms may also existleft ventricular systolic dyssynchrony. Left ventricular systolic dyssynchronyof dilated cardiomyopathy was significantly higher than that of hypertensiveheart disease.