The advantage of global strain compared to left ventricular ejection fraction to predict outcome after acute myocardial infarction

The aim of the study was to compare the ability of global strain and left ventricular ejection fraction (LVEF) to predict outcome after acute myocardial infarction (AMI). Left ventricular (LV) function was measured using strain by Doppler and LVEF in 77 patients. Measurements were performed at admission and after 10 ± 5 days. Outcome was measured as the combined end point of cardiac death, reinfarction and hospitalization for heart failure, unstable angina or life threatening arrhythmia. The patients were followed for 3.29 ± 1.59 years (range 0-5.22 years) and 17 cardiac events were registered. The cutoff value of LVEF was 44% for optimal prediction of outcome. We used LVEF ≤ 44% vs. > 44% and the corresponding global strain value ≥ -15.6% vs. < -15.6% to predict cumulative event-free survival. Both methods significantly predicted cardiac combined events at admittance and after 10 days with no difference. After 10 days, however, global strain remained the only significant predictor of outcome in a multivariate logistic regression model (P < 0.0001, odds ratio 1.79). Interobserver reproducibility measured as intraclass correlation was better for global strain than for LVEF (0.92 vs. 0.71). In conclusion, the measurement of global strain in patients with AMI may predict cardiac combined events to the same extent as LVEF in the acute phase and superior to LVEF after 10 days. In addition, global strain demonstrates better interobserver reproducibility and may become an improved bedside tool to evaluate LV function as a prognostic marker after AMI.     

Prognostic significance of right ventricular ejection fraction for persistent complex ventricular arrhythmias and/or sudden cardiac death after first myocardial infarction: Relation to infarct location, size and left ventricular function

To assess the prognostic significance of right ventricular dysfunctionafter a first myocardial infarction for complex ventriculararrhythmias and or sudden cardiac death in relation to infarctlocation, size and left ventricular function, a series of 127consecutive patients was prospectively studied and followedup for one year. Prior to hospital discharge, a 24-hour electrocardiographicrecording and radionuclide angiocardiography were performed.Right ventricular ejection fraction was related to inferiorinfarct location and size (r = 0.45, P<0.01): similarly leftventricular ejection fraction was related to anterior infarctlocation and size (r = 0.76, P7lt;0.001). The incidence of severeventricular arrhythmias was significantly higher in patientswith isolated right or left ventricular dysfunction comparedto patients with normal function; it was highest in patientswith severe depression of both ventricles. Patients with complexventricular arrhythmia and/or sudden cardiac death had significantlyreduced left and right ventricular ejection fractions. Detailedanalysis in patients with left ventricular ejection fraction> 0.40 vs. 0.40 showed that presence of complex ventricularectopic activity and/or sudden cardiac death after myocardialinfarction was related not only to left, but also independentlyto right ventricular dysfunction. These results imply a significantprognostic contribution of right ventricular dysfunction tothe occurrence of severe ventricular arrhythmias and/or suddencardiac death after myocardial infarction independent of andadditive to left ventricular dysfunction.     

新诊断的糖代谢异常对急性心肌梗死后左心室射血分数的影响

目的观察新诊断的糖代谢异常对急性心肌梗死后LVEF的影响。方法入选首次急性心肌梗死患者161例(对无糖尿病病史的患者发病7天后行口服葡萄糖耐量试验),根据检查结果及是否有糖尿病病史,分为正常糖耐量组(37例)、糖调节异常组(46例)、新诊断糖尿病组(37例)和既往已确诊糖尿病组(41例)。4组患者分别于发病后72 h内、30天行三维超声心动图检查评价左心室功能。结果糖调节异常组、新诊断糖尿病组和既往已确诊糖尿病组72 h内及30天随访时的LVEF均明显低于正常糖耐量组(72 h:(45.1±7.1)%、(45.0±7.2)%、(45.1±7.2)%vs(48.9±6.8)%,P<0.05;30天:(47.0±7.5)%、(47.8±7.3)%、(48.0±7.4)%vs (53.4±6.4)%,P<0.05]。结论新诊断的糖代谢异常也对急性心肌梗死后左心室功能产生不利的影响。     

年龄对急性ST段抬高型心肌梗死患者左室射血分数的影响

目的:分析年龄对急性ST段抬高型心肌梗死患者(STEMI)左室射血分数(LVEF)的影响.方法:收集急性STEMI患者245例,根据年龄分为5组:≤50岁组(49例)、51～60岁组(70例)、61～70岁组(62例)、71～ 79岁组(50例)、≥80岁组(14例);对临床基线资料(包括年龄、性别、高血压、糖尿病、高血脂、吸烟史、超急性期及急性期ST段抬高导联数、入院时及入院12～72 h肌钙蛋白、Killip分级、LVEF、是否接受冠状动脉介入治疗(PCI)和住院期间死亡等)进行比较分析.结果:多元线性回归分析显示,LVEF与年龄(P＜0 05)和肌钙蛋白(P＜0.05)呈负相关,随着年龄增长,LVEF降低;随着肌钙蛋白的增加,LVEF降低.在≤50岁组LVEF显著高于其余各年龄组(均P＜ 0.05),而≥80岁组LVEF则显著低于其余各组(均P＜0.05).≥80岁组KilliP分级≥Ⅱ级者显著高于其余各组(均P＜0.05).≥80岁组患者的住院期间病死率显著高于≤50岁组、51～60岁组、61～ 70岁组(均P＜0.05).结论:年龄可作为影响急性STEMI患者心功能的独立危险因素.     

Prognostic significance of the evolution of left ventricular ejection fraction in patients with acute myocardial infarction not treated with thrombolytic therapy

Several controlled trials on the thrombolytic treatment of acutemyocardial infarction (AMI) have failed to demonstrate thatthrombolysis has a simultaneous positive effect on left ventricularfunction and survival. One explanation may be that spontaneouschanges in left ventricular function occurred during the progressionof AMI in control patients. The aim of this study was to evaluatethe spontaneous evolution of left ventricular ejection fraction(LVEF) and its prognostic influence on early (1 month) and late(1 year) mortality in patients with AMI. We studied 216 patientsadmitted to our CCU within 24 h of the onset of symptoms. LVEFwas determined by radionuclide ventriculography on admission(RNV1) and at the end of the necrotic phase (RNV2). Fourteenpatients died before RNV2. On the basis of LVEF values at RNV1,the remaining 202 patients were divided into two groups: thosewith a normal LVEF (55%), and those with an abnormal LVEF (<55%). Among patients with a normal LVEF at RNV1 (64 patients) a significantincrease (>12%) in LVEF at RNV2 was observed in 12.5%, asignificant decrease (>12%) in 12.5% and no change at allin 75%. All of these patients survived, regardless of the evolutionof LVEF. In patients with an abnormal LVEF at RNV1 (138) a significantincrease (>5%) in LVEF at RNV2 was observed in 72.5%, a significantdecrease (>5%) in 6.5% and no change at all in 21%. In patientswith a LVEF increase, both early and late mortality were significantlylower than in patients with a LVEF decrease: (early mortality4% vs 55.5%, P<0.001; late mortality 6% vs 66.6%, P<0.001)respectively. In patients without any LVEF change, mortalitywas significantly lower than in patients with a LVEF decrease:(early mortality 10% vs 55.5%, P = 0.01; late mortality 14%vs 66.6%, P=0.004) respectively. In conclusion, our data demonstrate that a significant increasein LVEF occurs in most patients with an early depression ofleft ventricular function. This behaviour is associated witha low early and late mortality in comparison with the patientswith a LVEF decrease and is independent of thrombolytic treatment.When the early measurement of LVEF is normal the prognosis isnot influenced by LVEF evolution. These findings must be keptin mind when LVEF is used as a prognostic index and as an end-pointfor the evaluation of the effects of thrombolytic therapy.     

Aspirin does not influence the effect of angiotensin-converting enzyme inhibition on left ventricular ejection fraction 3 months after acute myocardial infarction

The aim of the present study was to evaluate the possible interaction between chronic aspirin therapy and angiotensin-converting enzyme inhibitor (ACE-I) on left ventricular ejection fraction (LVEF) in patients surviving an acute myocardial infarction (AMI). Forty-two patients with reduced LVEF were recruited from the warfarin aspirin reinfarction study (WARIS-II), a randomized, open study comparing enteric coated aspirin (160 mg/d), warfarin (INR 2.8--4.2) and the combination of aspirin (75 mg/d) and warfarin (INR 2.0--2.5) on mortality, reinfarction and stroke after AMI. LVEF and relevant biochemical measurements were performed before discharge and after 3 months. The overall LVEF increased during the study period from median 35 to 39% (P<0.001). There was no difference between patients on aspirin and warfarin regarding the main end point, LVEF. Furthermore, neither endothelin-1 nor ANP showed significant differences between the treatment groups. A possible interaction between ACE-I and aspirin might theoretically lead to reduced levels of renin activity in patients on aspirin, but we did not find any such inter-group difference. In conclusion, we did not find evidence of interaction between ACE-I and low-dose aspirin.     

Ventricular performance and prognosis after primary ventricular fibrillation complicating acute myocardial infarction

To examine the relationship between early arrhythmias, infarctsize and prognosis, we compared 22 consecutive patients survivingacute myocardial infarction (AMI) and primary ventricular fibrillation(VF) with a control population after AMI uncomplicated by primaryVF. Left ventricular ejection fraction (EF) was measured byradionuclide ventriculography before discharge from hospital.Mean EF was significantly reduced below normal following AMIwith or without primary VF (normal 0.57±0.05, mean±SD;P<0.01). Mean EF was lower among patients who survived primaryVF than among those with infarction uncomplicated by primaryarrhythmia (0.33 ±0.12 v. 0.46 ±0.07; P<0.01).There were striking differences in EF between those patientswith anterior and those with inferior infarction. Mean EF forthose surviving primary VF after transmural anterior infarction(0.23±0.06) was lower than those who had primary VF aftertransmural inferior infarction (0.43±0.06; P<0.01J.Normal left ventricular function was seen in four individualswho developed no further complications. Recurrent primary ventriculararrhythmia was seen v only in those individuals subsequentlyshown to have reduced EF. Low EF (< 0-35) was seen in 12patients with primary VF in the context of anterior infarction,five developed breakthrough ventricular arrhythmias despitetherapy and in a limited follow-up period, three have died.     

Serial left ventricular ejection fraction in acute myocardial infarction by cross-sectional echocardiography: correlation of changing ejection fraction with clinical course

Left ventricular volume and ejection fraction were measuredin 22 survivors of acute myocardial infarction by means of two-dimensionalechocardiography and using a Simpson's rule algorithm. Ten ofthe 22 patients experienced complications. For the group as a whole, there were no significant trends inleft ventricular volume and ejection fraction between the firstand third days and the third month after infarction. In thesubgroups with uncomplicated and complicated infarction, therewere trends towards increasing and decreasing ejection fractions,respectively, which Jailed to attain statistical significance,however. The difference in ejection fraction between both subgroupshad become significant at 3 months; 55.2+11.1% in uncomplicatedv. 41.3±6.9% in complicated cases (P>0.0l). Individualchanges in ejection fraction falling outside the limits of reproducibilityof the method as assessed previously were observed between day1 and day 3 in only 2 patients with uncomplicated and in 2 patientswith complicated infarction. Between day 1 and 3 months suchchanges occurred in 8 patients with uncomplicated infarction(upward in 5 and downward in 3), and in 8 patients with complicatedinfarcts (upward in 3 and downward in 5) We conclude that changes in ejection fraction as measured bytwo-dimensional echocardiography lend to correlate with complications.     

Evolution of left ventricular ejection fraction and its relationship to infarct size after acute myocardial infarction.

OBJECTIVES: The aim of this study was to investigate the evolution of left ventricular (LV) function and infarct size in patients with acute myocardial infarction (MI) treated with primary coronary stenting. BACKGROUND: Little evidence exists on the relationship between LV function and evolution of infarct size after MI. METHODS: This study included 626 patients with first acute MI who underwent 2 angiographic and 3 scintigraphic examinations within 6 months after the acute event. Angiographic left ventricular ejection fraction (LVEF) at baseline and at 6-month angiography, and perfusion defects before intervention and at 7- to 14-day and 6-month scintigraphy after intervention were measured. An analysis of 3-year follow-up was performed. RESULTS: Scintigraphic perfusion defect (median [25th, 75th percentiles]) was 24.6% [14.0%, 41.0%] of LV before intervention; it was reduced to 11.0% [5.0%, 24.0%] of LV at 7 to 14 days and further to 8.0% [2.0%, 19.0%] of LV at 6 months (p < 0.001). The LVEF was 51.6 +/- 12.0% before intervention and increased to 57.4 +/- 12.8% at 6 months (p > 0.001). Independent predictors of LVEF change were baseline LVEF (p < 0.001), initial perfusion defect (p < 0.001), early reduction in perfusion defect (p < 0.001), late reduction in perfusion defect (p < 0.001), peak creatine kinase-MB (p < 0.001), and smoking (p = 0.05). Three-year mortality was 1.2% in patients with improved LF function versus 5.6% in patients with worsened LV function (relative risk 0.29, 95% confidence interval 0.09 to 0.90; p = 0.03). CONCLUSION: Patients with acute MI show an improvement in LV function and a reduction in infarct size within 6 months after coronary reperfusion. This improvement is associated with better long-term survival.     

Long-term recovery of left ventricular function after primary angioplasty for acute myocardial infarction.

AIMS: To investigate changes in left ventricular function in the first 6 months after acute myocardial infarction treated with primary angioplasty. To assess clinical variables, associated with recovery of left ventricular function after acute myocardial infarction. METHODS: Changes in left ventricular function were studied in 600 consecutive patients with acute myocardial infarction, all treated with primary angioplasty. Left ventricular ejection fraction was measured by radionuclide ventriculography in survivors at day 4 and after 6 months. Patients with a recurrent myocardial infarction within the 6 months were excluded. RESULTS: Successful reperfusion (TIMI 3 flow) by primary angioplasty was achieved in 89% of patients. The mean ejection fraction at discharge was 43.7%+/-11.4, whereas the mean ejection fraction after 6 months was 46.3%+/-11.5 (P<0.01). During the 6 months, the mean relative improvement in left ventricular ejection fraction was 6%. An improvement in left ventricular function was observed in 48% of the patients; 25% of the patients had a decrease, whereas in the remaining patients there was no change. After univariate and multivariate analysis, an anterior infarction location, an ejection fraction at discharge < or =40% and single-vessel disease were significant predictors of left ventricular improvement during the 6 months. CONCLUSIONS: After acute myocardial infarction treated with primary angioplasty there was a significant recovery of left ventricular function during the first 6 months after the infarction. An anterior myocardial infarction, single-vessel coronary artery disease, and an initially depressed left ventricular function were independently associated with recovery of left ventricular function. Multivessel disease was associated with absence of functional recovery. Additional studies, investigating complete revascularization are needed, as this approach may potentially improve long-term left ventricular function.     

A mismatch index based on the difference between measured left ventricular ejection fraction and that estimated by infarct size at three months following reperfused acute myocardial infarction

Background and Aim

The reduction of left ventricular ejection fraction (LVEF) following ST-segment elevation myocardial infarction (STEMI) is a result of infarcted myocardium and may involve dysfunctional but viable myocardium. An index that may quantitatively determine whether LVEF is reduced beyond the expected value when considering only infarct size (IS) has previously been presented based on cardiac magnetic resonance (CMR). The purpose of this study was to introduce the index based on the electrocardiogram (ECG) and compare indices based on ECG and CMR.

Method and Results

In 55 patients ECG and CMR were obtained 3 months after STEMI treated with primary percutaneous coronary intervention. Significant, however moderate inverse relationships were found between measured LVEF and IS. Based on IS and LVEF an IS estimated LVEF was derived and an MI–LVEF mismatch index was calculated as the difference between measured LVEF and IS estimated LVEF. In 41 (74.5%) of the patients there was agreement between the ECG and CMR indices in regards to categorizing indices as > 10 or ≤ 10 and generally no significant difference was detected, mean difference of 1.26 percentage points (p = 0.53).

Conclusion

The study found an overall good agreement between MI–LVEF mismatch indices based on ECG and CMR. The MI–LVEF mismatch index may serve as a tool to identify patients with potentially reversible dysfunctional but viable myocardium, but future studies including both ECG and CMR are needed.     

Right and left ventricular ejection fractions: Relation to one-year prognosis in acute myocardial infarction

Right and left ventricular ejection fractions (RVEF and LVEF)were measured by radionuclide angiography in 423 patients withacute myocardial infarction (AMI). All investigations were performedat hospital discharge. Of 304 patients with first AM1, 26% hadnormal ejection fractions, 10% hada decrease in RVEF only, 46%a decrease in LVEF only, and 18% decrease in both RVEF and LVEF.Death from cardiac causes occurred in 52 patients in a one-yearfollow-up period. A reduced RVEF at hospital discharge had little,if any, relation to one-year mortality. In contrast, there wasan inverse curvilinear relationship between LVEF and one-yearcardiac mortality.     

Right and left ventricular ejection fractions: Relation to one-year prognosis in acute myocardial infarction

Right and left ventricular ejection fractions (RVEF and LVEF)were measured by radionuclide angiography in 423 patients withacute myocardial infarction (AMI). All investigations were performedat hospital discharge. Of 304 patients with first AM1, 26% hadnormal ejection fractions, 10% hada decrease in RVEF only, 46%a decrease in LVEF only, and 18% decrease in both RVEF and LVEF.Death from cardiac causes occurred in 52 patients in a one-yearfollow-up period. A reduced RVEF at hospital discharge had little,if any, relation to one-year mortality. In contrast, there wasan inverse curvilinear relationship between LVEF and one-yearcardiac mortality.     

Effect of flecainide on left ventricular ejection fraction

Antiarrhythmic agents may depress cardiac contractility andworsen heart failure. Flecainide is an effective antiarrhythmicdrug, but when administered orally in patients with left ventricular(LV) dysfunction, its effect on LV function is unknown. To assessthe effects of flecainide on cardiac function, LV ejection fraction(LVEF) was measured by radionuclide ventriculography in 36 patientswith LV dysfunction (LVEF 40%), prior to and 7 days after drugtherapy was initiated. To analyse the possibility of a dose-dependenteffect on LVEF, 18 patients received 200 mg day^–1 of flecainideand 18 patients with an identical initial LVEF (27±8vs 27±9) (NS) received 300 mg day^–1. The studywas stopped in 7 patients because of severe cardiac adverseeffects; in these patients the LVEF was significantly lower(15±7) than that of the 29 patients who completed theprotocol (27±8) (P<0.01). In patients who completedthe protocol, there was no significant change in LVEF eitherwith a daily dosage of flecainide of 200 mg day^–1 (27±8vs 27±8) or with 300 mg day^–1 (27±9 vs 28±13).Thus, in the patients with LV dysfunction studied, oral flecainidedid not significantly affect LV function either with a low orwith the ususal daily dosage. However in patients with severeimpairment of LV function (LVEF<30%) flecainide must be usedcarefully owing to a higher incidence of adverse effects oncardiac rhythm.     

An accurate and simplified method to calculate angiographic left ventricular ejection fraction

An accurate and simplified method to calculate left ventricular (LV) ejection fraction (EF) derived from the ellipsoidal formula for LV volume calculation is described. The LV minor axis (D) is obtained from the average of three equidistant LV diameters at end-diastole (Ded) and end-systole (Des), and the shortening fraction of D² (%δD²) calculated as (D²ed – D²es)/D²ed. EF is calculated as EF = [ δD² + ([1 – δD²] × δL)] × 100, where δL = the shortening fraction of the long axis. The coefficient of correlation between the EF by this method and the EF derived from measurements of LV volumes with the area-length method was 0.98, SEE = 3.57% (n = 50). No significant over- or underestimation was observed according to the regression equation Y = 0.922x + 0.82. Thus, this simplified method allows accurate LVEF calculation without the need for planimetry of LV area.     

急性心肌梗塞后左室舒张功能影响因素的探讨

为探讨急性心肌梗塞（ＡＭＩ）左室舒张功能的变化及影响因素，我们用脉冲多普勒超声心动图测量了７２例ＡＭＩ患者的左室舒张功能，并用多元逐步回归对其影响因素进行了分析。结果表明，７２例病人中Ｅ／Ａ＜１者４１例，占５６．９％。ＡＭＩ后左室舒张功能除受年龄影响外，梗塞面积的大小直接影响左室舒张功能，但与梗塞部位无关，梗塞前心绞痛可减轻梗塞后左室舒张功能的损害，是通过减小梗塞面积而实现的。溶栓治疗可以改善心肌梗塞后的左室舒张功能。