Effect of burden and origin sites of premature ventricular contractions on left ventricular function by 7-day Holter monitor

Recent studies have shown that premature ventricular contractions （PVCs） could enlarge the heart, but its risk factors are incompletely understood as a single 24-hour recording cannot reflect the true PVC burden due to day-to-day variability. Our purpose was to investigate the effect of burden and origin sites on left ventricular （LV） function in patients with PVCs by 7-day Holter electrocardiography （ECG）. From May 2012 to August 2013, 112 consecutive patients with PVCs were recruited from the authors＇ affiliated hospital. All patients received 2-dimensional transthoracic echocardiography, 12-lead routing ECG and 7-days Holter ECG. Serum N-terminal pro- brain natriuretic peptide （NT-proBNP） levels were measured. A total of 102 participants with PVCs were included in the final analysis. Origin of PVCs from the tricuspid annulus had the highest burden and NT-proBNP level. LV papillary muscle had a higher LV ejection fraction （EF） level and a lower LV end-systolic dimension （ESD） than other PVC foci （P〈0.05）. The high burden group had a higher LV end-diastolic dimension （EDD） and LVESD but lower LVEF than the other two groups （P〈0.05）. Female, older age, physical work, and history of PVCs had a significantly positive correlation with symptoms. Male, older age, physical work, and high burden were positive predictors of enlarged LVEDD, LVESD and higher serum NT-proBNP level, but lower LVEF. Seven-day dynamic ECG Holter monitor showed the true PVC burden on patients with PVCs. PVCs with a lower burden or origin from the LV papillary muscle and the fascicle were relatively benign, while PVCs with a higher burden or origin from the tricuspid annulus may lead to cardiac dysfunction.

The Relationships between Serum Concentration of IGF-I and Left Ventricular Function as well as Coronary Collateral Circulation in Patients with Coronary Artery Disease

Objective To investigate therelationships between serum concentration of insulin -like growth factor - I (IGF-I) and left ventricular function as well as coronary collateral circulation in patients with coronary artery disease (CAD) . Methods In 41 patients with CAD and 15 control subjects without CAD, the concentrations of serum IGF - I were measured using radioimmunoassay. The relationships between the concentration of serum IGF - I and Leaman coronary artery score, Rentrop grade of coronary collateral circulation, left ventricular ejection fraction (LVEF) as well as left ventricular wall motion Cortina score were assessed. Results 1. There was no significant difference in the mean level of serum IGF -I between the CAD group and the control group (107. 92±44.74 ng/ml vs 113.05 ±33. 65 ng/ml, P> 0. 05), but the IGF - I concentrations in the subgroup with collateral circulation were significantly greater than that in the control group (147. 33 ±29. 92 ng/ml vs 113. 05±33. 65 ng/ml, P < 0. 01) or in the subgroup without collateral circulation (147. 33 ±29. 92 ng/ml vs 80. 01±29. 75 ng/ml , P < 0. 01). 2. The serum concentration of IGF -I had no significant correlation to the Leaman coronary artery score. 3. The serum level of IGF -I had significantly positive correlation to both LVEF ( r = 0. 45, P < 0. 001) and the Rentrop grade of coronary collateral circulation ( r = 0. 74, P < 0. 001), and was negatively related to the left ventricular wall motion Cortina score (r = -0. 53, P < 0. 001). 4. The Leaman coronary artery score had no significant correlation to the Rentrop grade of coronary collateral circulation. 5. The Leaman coronary artery score was related to neither the LVEF nor the Cortina score in the whole CAD group. In the subgroup without coronary collateral circulation, however, the Leaman score had significantly negative correlation to LVEF ( r = - 0. 46, P < 0. 05) and positive correlation to the Cortina score (r = 0. 47, P < 0. 05) . Conclusions The serum concentration of IGF -I was associated with both left ventricular function and coronary collateral circulation in patients with CAD. IGF -I may play a role in promoting coronary collateral circulation and in protecting left ventricular function in patients with coronary artery disease.

Left Atrial Volume Index in Patients with Dilated Cardiomyopathy—Correlation with Left Ventricular Function

Background: The aim of this study was to determine the relation of left atrial (LA) volume and LA volume index with left ventricular function and to determine the association of duration of symptoms and left atrial volume index in patients with dilated cardiomyopathy. Materials and Methods: This was an observational, single centre study conducted in India. A total of 50 patients who were admitted to department of cardiology from July, 2008 to February, 2009 with diagnosis of dilated cardiomyopathy and an ejection fraction of <40% were included. Results: Of the 50 patients, 34 (68%) were males. 27 (54%) patients were in NYHA class II and 23 (46%) patients were in NYHA class III. LA volume was found to be ≥40 ml in all patients. LV function and LA volume were found to be correlated (r = -0.789, p < 0.01). Similarly, there was a correlation between LV function and LA volume index (r = -0.826, p < 0.01). There was no correlation between LA volume index and duration of symptoms (r = 0.04). Conclusion: It can be concluded that there is a strong inverse correlation between LA volume and left ventricular function and also between LA volume index and left ventricular function. The patients with NYHA class III were having larger left atrial volume than those with NYHA class II. Moreover, the duration of symptoms has no correlation with left atrial volume index.

Viable Myocardium Impact on Left Ventricular Function after Late Revascularization of Infarct-related Artery in Acute Myocardial Infarction

Objectives The long-term benefit of late reperfusion of infarct-related artery （IRA） after acute myocardial infarction （AMI） is controversial, and the benefit mechanisms remain uncertain. Low dose dobutamine stress echocardiography （LDSE） can identify viable myocardium and predict improvement of wall motion after revascularization. Methods Sixtynine patients with first AMI who did not received early reperfusion therapy were studied by LDSE at 5 to 10 days after AMI. Wall motion abnormality and left ventricular size were measured at the same time. Successful PCI were done in all patients at 10 to 21 days after AMI onset. Patients were divided in two groups based on the presence or absence of viable myocardium. Echocardiography was repeated six months later. Results There were 157 motion abnormality segments. 89 segments （57%） were viable during LDSE. 26 patients （38%） with viability and 43 （62%） without. In viable group, left ventricular ejection fraction （LVEF） was increased （P 〈 0.05）, and left ventricular end systolic volume index （LVESVI） and wall motion score （WMS） were decreased （P 〈 0.05 and P 〈 0.01） significantly at 6 months compared with baseline. But in patients without viability, LVEF was decreased （P 〈 0.01）, and LVESVI and left ventricular end diastolic volume index （LVEDVI） were increased （P 〈 0.05） significantly after 6 months, and the WMS did not changed （P 〉 0.05 ）. LVEF increased （P 〈 0.05 ） and WMS decreased （P 〈 0.05） on LDSE during acute phase in patients with viability, but they were not changed in the nonviable group. Conclusions Late revascularization of IRA in patients with presence of viable myocardium after AMI is associated with long-term preservation left ventricular function and less ventricular remodeling. Improvement of left ventricular systolic function on LDSE indicates late phase recovery of left ventricular function after late revascularization.

ASSESSMENT OF LEFT VENTRICULAR FUNCTION IN HEALTHY SUBJECTS BY PUSLED WAVE DOPPLER TISSUE IMAGING

Objective To examine the clinical application of pulsed Doppler tissue imaging(DTI)for regional left ventricular function assessment in normal subjects. Methods We examined 50 healthy subjects(range 12-42 years,mean age 28.3 ± 6.9 years)using pulsed Doppler tissue imaging to characterize the diastolic and systolic velocity profiles of mitral annulus. Recordings were made along the long axis in the apical 4-chamber, 2-chamber, and long apical views of 6 sites(posterior-septum, lateral, anterior, inferior, anterior-septum, posterior)at the mitral annulus. Myocardial velocities were determined with use of variance F statistical analysis. Correlation analysis was employed to test the relationship between age and mitral annular velocities. Results Both early diastolic and systolic velocities at the septum were lower than other sites. There were no differences in mitral annulus late diastolic velocities. Mean early diastolic and systolic velocities was negatively correlated with age. Conclusions Doppler tissue imaging can directly reflect regional left ventricular function.

Evaluation of Left Ventricular Function after Percutaneous Recanalization of Chronic Coronary Occlusions: The Role of Two-Dimensional Speckle Tracking Echocardiography

Background: The recanalization of a chronic total coronary occlusion is the possible way to improve left ventricular (LV) function through the recovery of hibernating myocardium. Aim: The aim of this study is to evaluate the role of 2D speckle tracking in evaluation of the left ventricular (LV) systolic function in chronic total occlusion (CTO) patients before and at 1 day as well as 3 months after percutaneous coronary intervention (PCI). Patients and Methods: A prospective observational study included 40 patients diagnosed with coronary angiography to have a chronic total occlusion. Percutaneous coronary revascularization was performed according to standard practices with the femoral approach. Conventional 2D echocardiography was used to assess LV functions and wall motion abnormalities scoring index (WMAI). Using speckle-tracking echocardiography was to measure global longitudinal strain (GLS) and. Follow-up of patients was done at day 1 and 3 months later after PCI. Results: Forty patients were included in this study, with a mean age of 58.55 ± 7.98 years. GLS and WMAI difference at baseline and follow-up shows a positive correlation with left ventricular ejection fraction (LVEF) changes at baseline and follow-up (p Conclusion: The results of this study provide evidence to support the clinical use of 2D-STE to monitor the early changes of LV function. In patients undergoing CTO revascularization, change in GLS was more sensitive predictors for LV function improvement at 3-month follow-up.

Usefulness of myocardial performance index for assessing right ventricular function after percutaneous closure of atrial septal defect

Objective Assessment of right ventricular function in patients with atrial septal defect (ASD) is difficult. The Doppler myocardial performance index (MPI) may provide a method of assessing function in these patients. The purposes of this study were to evaluate the right ventricular function and its changes in patients with ASD after transcatheter closure of ASD. Methods MPI, defined as the sum of isovolumic relaxation time and isovolumic contraction time derived by ejection time, was measured from tricuspid inflow and right ventricular outflow;Doppler velocity profiles recorded during routine echocardiography.Twenty nine patients (13 men, 16 women;mean age 25.28±12.69, range 6 to 57 years) were diagnosed to secundum ASD [the stretched diameters of ASD were from 9 To 36 (24.91±7.98) mm], and had a successfully placed Amplatzer septal occluder (ASO) (the sizes of ASO were from 11 to 40 mm );there were 81 sex-matched, age-matched healthy people (control group 41men, 40 women;mean age 29.02 ± 14.22, range 4 to 45 years ). MPI was measured again on 3 days and 1 month after closure of ASD. Change in the study group was assessed and compared to the control subjects with structurally normal hearts. A complete 2-dimensional and Doppler echocardiographic examination was performed in all study groups. Results 1) The isovolumic relaxation and isovolumic contraction times [respectively(77.59 ± 14.39)ms vs (60.93 ±12.94)ms, P<0.0001;(28.28 ±10.88)ms vs (23.64 ±9.01)ms, P=0.027] were prolonged, and ejection time [(260.65 ±21.86 )ms vs (271.85 ± 21.92)ms, P=0.033] was shortened in patients with ASD compared with that in control subjects, resulting in a marked increase in the MPI(0.40 ± 0.07 vs 0.31 ± 0.05, P<0.0001) from normal values;2) by Pearson's correlations, the MPI had no correlation with heart rate and blood pressure in control subjects and patients with ASD, but it correlated positively with age in patients with ASD;3) by Pearson's correlations, the MPI correlated positively with the diameter of ASD and pulmonary artery pressure;4) after transcatheter closure of ASD, the MPI decreased markedly. Conclusions 1) MPI is a conceptually new, simple, and reproducible Doppler index in patients with ASD;2) MPI is free from the effect of age, heart rate and blood pressure;(3) MPI appears to be relatively dependent on changes in the diameter of ASD and pulmonary artery pressure;4) the right ventricular function was improved after transcatheter closure of ASD.(J Geriatr Cardiol 2007;4:220-224.)

EFFECT OF AROTINOLOL ON LEFT VENTRICULAR FUNCTION IN PATIENTS WITH IDIOPATHIC DILATED CARDIOMYOPATHY

Objective To evaluate the efficacy and safety of long-term treatment with arotinolol in patients with idiopathic dilated cardiomyopathy(IDCM).Methods Sixty-three patients with IDCM were evaluated at baseline and after 12-month therapy with arotinolol.The conventional therapy for congestive heart failure was continued throughout the study with arotinolol as the only β-blocker.Left ventricular function was assessed with the New York Heart Association functional class and two-dimensional echocardiography.Results After 12-month arotinolol treatment,there was a significant improvement in left ventricular systolic function.Left ventricular end-systolic dimension significantly decreased from 59.52±8.83 mm to 50.89±8.17 mm(P<0.001).Left ventricular ejection fraction significantly increased from 27.39%±7.94% to 41.13%±9.45%(P<0.001).Left ventricular mass index decreased from 150.47±42.42 g/m2 to 141.58±34.36 g/m2(P<0.01).No adverse events leading to premature discontinuation of study drug occurred.Conclusion In this preliminary study,12-month arotinolol treatment has a favorable effect on left ventricular function in patients with IDCM,and it is safe and well tolerated.

Effect of arotinolol on right ventricular function in patients with dilated cardiomyopathy

Objective Dilated cardiomyopathy(DCM) is generally considered to be accompanied by both left and right ventricular dysfunction,but most studies only analyze the left ventricular function. In this study,we evaluated the effect of arotinolol on right ventricular function in patients with DCM. Methods Right ventricular ejection fraction(RVEF) and right ventricular diameter(RVD) were measured by two-dimensional echocardiography(2-DE) in 33 DCM patients;RVEF measured by first-pass radionuclide angiography(FPRA) was compared with that by 2-DE. Results The treatment with arotinolol for one year resulted in a reduction in the right ventricular diameter(baseline,23.0 ± 8.3 mm vs after one-year treatment,20.7 ± 5.4 mm;P=0.004 ) and an associated increase in ejection fraction(baseline,36.9 ± 10.3% vs after one-year treatment,45.8 ± 9.6%;P < 0.001 ) ;there is a high correlation between the 2-DE method and radionuclide ventriculographic method. The correlation coefficient is 0.933(P<0.001) . Conclusion Arotinolol therapy could not only improve left ventricular function,but also improve right ventricular function in DCM patients.

An Overview of the Consequences of Distal Coronary Microembolization on Left Ventricular Function, Perfusion and Viability

Annually, an estimated 1,285,000 in-patient angioplasty procedures, 1,471,000 inpatient diagnostic cardiac catheteri-zations and 68,000 inpatient defibrillator implantations are performed. The direct and indirect cost of cardiovascular diseases for 2007 is approximately $431.8 billion. The occurrence of plaque rupture with subsequent microemboli of atherosclerotic and thrombolytic debris into small coronary vessels has been confirmed. Microinfarction results from microemboli that are shed following coronary interventions. The aims of this review are to: 1) detect heterogeneous microinfarction using viability imaging, 2) characterize the consequences of distal coronary microembolization on left ventricle function and perfusion and 3) illustrate the progress of non-invasive imaging modalities in assessing distal coronary microembolization.

Accuracy of left ventricular function from electrocardiographygated myocardial perfusion SPECT by MyoMetrix in Chinese

This work was to determine threshold values for accurate measurements of left ventricular end-diastolic volume(EDV),end-systolic volume(ESV),and ejection fraction(EF) from electrocardiography-gated myocardial perfusion imaging(MPI) in Chinese,and these data were compared with those of echocardiography.A total of 110 patients with definite or suspected coronary artery disease were referred for both gated MPI and echocardiography within 1 week.The EDV,ESV,and EF automatically measured by MyoMetrix and echocardiography were analyzed using Bland-Altman plot correlation and paired t test.The results showed that these parameters quantified by MyoMetrix software were correlated,moderately to highly,with those on echocardiography(ρ,r ≥0.75,P<0.01).However,the EF was not significantly correlated,with post-exercise MPI ESV of <15 mL or resting MPI ESV of <20 mL.At or above this ESV value,EF was underestimated by MyoMetrix(t≥ 4.60,P<0.01).In a word,a small ESV was underestimated by MyoMetrix,which could lead to EF overestimation.On the contrary,a normal or large ESV was overestimated by MyoMetrix,which led to EF underestimation.

Tei index evaluates left ventricular function changes after on-pump and off-pump coronary artery bypass surgery

Objective: To compare function recovery of left ventricle after off-pump and on-pump coronary artery bypass (OPCAB and ONCAB) using Tei index. Methods: Twenty-four patients with coronary artery disease were enrolled, twelve of which received OPCAB and the others underwent ONCAB. Left ventricular ejection fraction (LVEF), E/A ratio at mitral orifice and Tei index were measured using transthoracic echocardiography before surgery and 3-7 days, 1 month, 3 months and 6 months after surgery. Results:Tei index of both groups decreased 3-7 days after surgery, with OPCAB group's lower than ONCAB group's. The difference between pre-and post-OPCAB was significant (P<0. 01 ), but not for ONCAB group (P>0. 05). Tei index of ONCAB decreased more significant than that of OPCAB 1 month after surgery, there was statistical difference between 3-7 days and 1 month after surgery in ONCAB (P<0. 01). Afterwards, Tei index of the 2 groups decreased steadily with no significant difference between them at other time points. LVEF and E/A ratio decreased at first, then increased gradually, with no statistical differences between the 2 groups at all time points. Conclusion: The recovery of left ventricular function after OPCAB is earlier than ONCAB. Tei index is more sensitive than LVEF and E/A ratio in detecting cardiac function recoveries and can be considered as an accurate and simple method to evaluate left ventricular systolic and diastolic function.

QUANTIFICATION OF RIGHT VENTRICULAR FUNCTION IN ATRIAL SEPTAL DEFECT USING ULTRASOUND- BASED STRAIN RATE IMAGING

Objective To study the validation of ultrasound-based strain rate imaging in the quantitative assessment of right ventricular (RV) function in atrial septal defect (ASD). Methods Tissue Doppler images (TDI) of RV longitudinal and short axes were recorded from the apical 4-chamber view and the subcostal short-axis view in 18 normal controls, 28 children with ASD and 14 children after Amplazter closure of ASD respectively. Peak systolic velocities (V), peak systolic strain rates (SR), peak systolic strains (S) at the basal segment, middle segment of RV lateral wall and the basal septum from the longitudinal axis, the middle segment of RV free wall from the short axis were quantitatively measured using QLAB TM tissue velocity quantification software system respectively. Peak dp/dt from the RV isovolumic contraction determined during the right cardiac catheterization in 28 ASD patients was used as the gold standard of RV contractility. Peak systolic indices were compared against max dp/dt by linear correlation. Results Peak systolic indices at the basal and middle segments of RV lateral wall from the longitudinal axis increased significantly in 28 ASD patients.Peak systolic indices at the basal septum also increased in patient group, but not significantly. Significant decreases in peak systolic indices at the basal and middle segments of RV lateral wall were observed after the Amplatzer closure in 14 ASD patients. There was no significant difference at the middle segment of RV free wall from the short axis between patient group and normal control. A strong correlation was found between max dp/dt and peak systolic indices at the basal and middle segments of RV lateral wal l (P<0.05). Conclusion Ultrasound-based strain rate imaging can assess quantitatively RV function in CHD. Peak systolic strains determined at the basal and middle segments of RV lateral wall are strong noninvasive indices of RV contractility.

Frequency domain cardiography and radionuclide ventriculography for evaluation of left ventricular function in coronary artery disease

Fifty-six patients with chest pain underwent selective coronaryangiography,radionuclide ventriculography (RNV) and frequency domaincardiography (FCG) to evaluate left ventricular function in coronary artery dis-ease (CAD).The sensitivity,specificity and accuracy of FCG were 87.5%,77.8%and 82.9%,respectively,which were slightly less than those of RNV (92.5%,88.9% and 90.8%,respectively).The changes of FCG scores were negatively corre-lated with changes of LVEF (r=-0.586,P【0.01),and TS (r=-0.679,P【0.01).These results indicate that FCG may be useful for the evaluation of leftventricular function in patients with CAD.

Real-time Three-dimensional Echocardiography:A Feasible and Accurate Method for Measuring Right Ventricular Function in Pulmonary Hypertension

Right ventricular function is independently associated with poor clinical outcomes in patients with various cardiovascular diseases including pulmonary hypertension(PH).The complex geometry and mode of contractility means the right ventricle(RV)inlet and outlet are not in line;hence,2-dimensional echocardiography fails to accurately quantify RV volumes and function in such patients.Three-dimensional echocardiography(3DE)allows for reliable and reproducible quantification of RV volumes and function by overcoming these limitations of conventional echocardiography.This review focuses on the 3DE assessment of RV function in patients with PH and discusses the following points:(1)acquiring an RV data set for 3DE imaging,including details of all available 3DE systems and software utilized in daily practice;(2)the reliability and feasibility of RV remodeling measured with 3DE with different modalities in patients with PH;and(3)the prognostic value of 3DE-derived RV function in such patients.

The Clinical Association of Left Atrial Function with Left Ventricular Ejection Fraction

The left atrium (LA) has been recognized as a morphophysiological barometer of left ventricular (LV) diastolic dysfunction. Because in the myocardial ischemia cascade where LV diastolic dysfunction often precedes LV systolic dysfunction, the LA which fashions as an early marker of diastolic anomaly, could equally reflect a declining LV function and/or be a good predictor of potential sequelae. We assessed this association of LA function with reduced LV systolic function among hospitalized patients. Among patients with reduced LV ejection fraction, LA passive ejection fraction was lower (0.172 ± 0.12 vs. 0.232 ± 0.14, p = 0.013) whereas LA kinetic energy was higher (6.48 ± 6.3 vs. 4.57 ± 3.5, p = 0.005). Echocardiographic assessment of LA function, therefore, appears correlated with LVEF and could be important when risk stratifying hospitalized patients.

Three hours continuous injection of adenosine improved left ventricular function and infarct size in patients with ST-segment elevation myocardial infarction

Background The definitive treatment for myocardial ischemia is reperfusion. However, reperfusion injury has the potential to cause additional reversible and irreversible damage to the myocardium. One likely candidate for a cardioprotection is adenosine. The present study aimed at investigating the effect of intravenous adenosine on clinical outcomes in patients with ST-segment elevation myocardial infarction （STEMI） undergoing primary percutaneous coronary intervention （PCI）. Methods Patients with STEMI within 12 hours from the onset of symptoms were randomized by 1：1：1 ratio to receive either adenosine 50μg-kg-1.min-1 （low-dose group, n=31）, or 70 μg.kg-1.min1 （high-dose group, n=32）, or saline 1 ml/min （control group, n=27） for three hours. Drugs were given to the patients immediately after the guide wire crossed the culprit lesion. Recurrence of no-reflow, TIMI flow grade （TFG） and TIMI myocardial perfusion grade （TMPG）, and collateral circulation were recorded. The postoperative and preoperative ST segment elevation sum of 18-lead electrocardiogram （ECG） and their ratio （STsum-post/STsum-pre） were recorded, as well as the peak time and peak value of CK-MB enzyme. Serial cardiac echo and myocardial perfusion imaging were performed at 24 hours and 6 months post-stenting. The primary endpoint was left ventricular function, and infarct size. The secondary end-point was the occurrence of cardiac and non-cardiac death, non-fatal myocardial infarction, and heart failure. Results A total of 90 STEMI patients were studied. No-reflow immediately after stent procedure was seen in 11 （35.5%） patients in the control group, significantly different from 6.3% in the low-dose group or 3.7% in the high-dose group （both P=0.001）. STsum-post/STsum-pre in the low-dose and high-dose groups was significantly different from the control group （low-dose group vs. control group, P=0.003 and high-dose group vs. control group, P=0.001）, without a dose-dependent pattern （P=0.238）. The peak value of CK-MB enzyme was significantly reduced in the high-dose group compared to the control group （P=-0.024）. Compared to the left ventricular ejection fraction （LVEF） in control group, LVEF in the low-dose group increased by 5.8% at 24 hours （P=0.012） and by 10.9% at 6 months （P=0,007）, LVEF in the high-dose group increased by 9.5% at 24 hours （P=0.001） and by 10.0% at 6 months （P=0.001）, respectively. Significant reduction of infarct size by 24.2% was detected in the high-dose group vs. low-dose or control groups （P=0.008）. There was no significant difference regarding secondary endpoints at 6 months among the treated groups. Cardiac function by NYHA classification in both the low-dose and the high-dose groups was improved significantly （P=0.013, P=0.016）. Conclusion Intravenous adenosine administration might significantly reduce the recurrence of no-reflow, with resultant improved left ventricular systolic function. High-dose adenosine was further associated with significant reduction of infarct size.

Assessment of Regional Left Ventricular Myocardial Function in Rats after Acute Occlusion of Left Anterior Descending Artery by Two-dimensional Speckle Tracking Imaging

This study evaluated the change in regional left ventricular myocardial function in rats following acute occlusion of the left anterior descending coronary artery （LAD） by using two-dimensional speckle tracking imaging （2D-STI）. Sixty Wistar rats were randomly divided into two groups, a myocardial infarction （MI） group, in which 50 rats were subjected to LAD occlusion for 30–45 min, and a sham-operated （SHAM） group that contained 10 rats serving as control. Echo-cardiography was performed at baseline and 1, 4 and 8 week（s） after the operation. High frequency two-dimensional images of left ventricular short axis at papillary muscle level were recorded. Peak systolic radial strain （PRS） and circumferential strain （PCS） were measured in the mid-ventricle in short-axis view by using EchoPAC workstation. Left ventricular internal diameter at diastole （LVIDd） and systole （LVIDs）, fractional shortening （FS）, ejection fraction （EF） and left ventricular mass （LVM） were measured by anatomical M-model echocardiography. Infarct size was measured using triphenyl tetrazolium chloride （TTC） staining 1 week and 8 weeks after the operation. Fibrosis of left ventricu-lar myocardium was displayed using Van Gieson staining 1 week after the infarction. In terms of the TTC staining results, the left ventricle fell into three categories： infarcted, peri-infarcted and remote myocardial regions. Compared with those at baseline and in the SHAM group, （1） PRS and PCS in the infarcted, peri-infarcted and remote myocardial regions were significantly decreased in the MI group within 1 week after the operation （P〈0.05） and the low levels lasted 8 weeks; （2） Compared with those at baseline, LVIDd, LVIDs, FS, EF and LVM in the MI group showed no significant dif-ference 1 week after the operation （P〉0.05）. However, LVIDd, LVIDs and LVM were increased sig-nificantly 4 and 8 weeks after the operation （P〈0.05）, and FS and EF were decreased substantially （P〈0.05）. Van Gieson staining showed that fibrosis developed in all the three myocardial regions to varying degrees. It is concluded that 2D-STI is non-invasive and can be used to assess regional func-tion of myocardium with different blood supply in rats following acute occlusion of the LAD, and can be used as a sensitive and reliable means to follow up the process of left ventricular remodeling.

Perioperative changes of ventricular function and three indicators of myocardial injury during orthotopic liver transplantation

Patients undergoing orthotopic liver transplantation may develop significant haemodynamic instability, especially during anhepatic phase and immediately after reperfusion of the graft. The haemodynamic instability may be caused directly by myocardial depression due to pathogenic substances released from the liver, or by acute blood loss.^1 Creatine kinase（CK） and its MB fraction （CK-MB） are sensitive and specific indicators to reflect myocardial damage.^2 Cardiac troponin I （cTnl） is a specific and sensitive marker of myocardial necrosis.^3 This study assessed perioperative cardiac function using three indicators （CK,CK-MB,and CTnl） to evaluate perioperative myocardial damage.