A prospective comparison of echocardiographic wall motion score index and radionuclide ejection fraction in predicting outcome following acute myocardial infarction

Incidence and Predictors of Left Ventricular Thrombus Formation After Acute Myocardial Infarction With ST-Segment Elevation

Background and objective Our prospective study aimed to evaluate the frequency and risk factors of left ventricular thrombus (LVT) occurring after acute ST-segment elevation myocardial infarction (STEMI) in the era of primary percutaneous coronary intervention (PCI). Methods Our study included 131 patients diagnosed with acute STEMI who were followed up and treated. The presence of the thrombus was determined by transthoracic echocardiography (TTE). Study patients were evaluated as cases of thrombus (+) and thrombus (-). The relationship of electrocardiographic measurements such as the number of leads with pathological Q waves, ST segment deviation score, QT dispersion, and echocardiographic measurements such as ejection fraction (EF), end-systolic and end-diastolic volumes, and wall motion score index (WMSI) with LVT was investigated. LVT risk factors were identified. Results The median age of the study patients was 59.7 ± 11.7 years, and 84.7% were male. The incidence of LVT was 17.6% (23 patients). While the anterior STEMI rate was 86.9% in the thrombus (+) group, it was 50.9% in the thrombus (-) group (p<0.001). While WMSI was 2.1 ± 0.44 in the thrombus (+) group, it was calculated as 1.40 ± 0.31 in the thrombus (-) group (p<0.001). In the thrombus (+) group, EF was found to be lower, end-systolic and end-diastolic volumes were higher, and the rate of moderate and severe mitral regurgitation and the rate of aneurysmatic segment detection were higher. LVT had a moderate correlation with WMSI (r: 0.613; p<0.001), the presence of an aneurysmatic segment (r: 0.549; p<0.001), and EF (r: -0.514; p<0.001). Presentation with anterior STEMI (odds ratio [OR]: 4.266; p<0.001), WMSI (OR: 7.971; p=0.012), the number of leads with pathological Q waves detected at discharge (OR: 3.651; p=0.009), the presence of an aneurysmatic segment (OR: 2.089, p=0.009), and EF (OR: 1.129, p=0.006) were identified as independent risk factors of the presence of LVT. The area under the curve for WMSI was found to be 0.910 (95% CI: 0.852-0.968). A WMSI cut-off of 1.56 identified LVT with 91% sensitivity and 70% specificity (Youden index: 0.617). Conclusion In the primary PCI era, LVT incidence after acute STEMI is still significant. Anterior STEMI, the number of leads with pathological Q waves detected at discharge, WMSI, aneurysm formation, and low EF are independent risk factors for LVT. Among these risk factors, the variable with the highest diagnostic power is WMSI.

Wall Motion Score Index Predicts Persistent Moderate or Severe Secondary Mitral Regurgitation and its Prognostic Role in Patients Undergoing Percutaneous Coronary Intervention

Background

Patients with secondary mitral regurgitation (sMR) often present with greater mortality and comorbidity, which may be predicted by some risk factors. This study was designed to investigate the prognostic meaning of the echocardiographically detected wall motion score index (WMSI) in coronary artery disease (CAD) patients with moderate or severe baseline sMR who underwent percutaneous coronary intervention (PCI) therapy.

Methods

The present study was a multi-center and prospective cohort of consecutive CAD patients with baseline moderate or severe sMR who underwent PCI. All underwent echocardiography at baseline and at follow-up after PCI to assess sMR and WMSI. The primary endpoint was the persistence of moderate or severe sMR after the second echocardiographic measurement. Logistic and Cox proportional hazards models were constructed for the primary (persistent moderate or severe sMR) and secondary (worsening heart failure [HF]; all-cause mortality; cardiovascular-specific mortality; and major adverse cardiovascular events [MACE]) endpoints.

Results

Among 920 participants, 483 had WMSI values of ≥ 1.47, and 437 were less. Of all the participants, 366 (39.8%) continued to have moderate or severe sMR after the second echocardiogram measurement. After full adjustment for confounders, elevated WMSI after PCI was independently associated with the primary endpoint during 3-12 month follow-up. Similarly, elevated WMSI was associated with increased risk of worsening HF, all-cause mortality, cardiovascular-specific mortality, and MACE.

Conclusions

Persistent moderate or severe sMR is common (approximately 40%) in PCI patients. Elevated WMSI in CAD patients after PCI is a predictor of persistent moderate or severe sMR and has independent negative prognostic value. Patients with CAD and sMR should be monitored for WMSI to identify those at higher risk of mortality and comorbidity.

Prognostic value of summed motion score assessed by gated SPECT myocardial perfusion imaging in patients with dilated cardiomyopathy

Background

The prognosis of patients with dilated cardiomyopathy (DCM) is poor and new indicators are urgently needed to predict lethal cardiac events. This study aimed to investigate the value of summed motion score (SMS) in predicting cardiac death of DCM patients using gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI).

Methods and results

Eighty-one patients with DCM who underwent 99mTc-MIBI gated SPECT MPI were retrospectively enrolled and were divided into cardiac death and survivor groups. The functional parameters of left ventricle including SMS were measured using quantitative gated SPECT software. During the follow-up period of 44 (25, 54) months, 14 (17.28%) cardiac deaths were observed. Compared with the survivor group, SMS was significantly higher in the cardiac death group. Multivariate cox regression analysis showed that SMS was an independent predictor for cardiac death (HR 1.34, 95% CI 1.02–1.77, P = 0.034). SMS also provided incremental prognostic value over other variables in the multivariate model as determined by likelihood ratio global chi-squared test. In the Kaplan-Meier survival analysis, the event-free survival rate was significantly lower in the high-SMS (HSMS) group than the low-SMS (LSMS) (log-rank P &lt; 0.001). Furthermore, the area under curve (AUC) of SMS was larger than that of LVEF at the 12th month of follow-up (0.85 vs. 0.80, P = 0.045).

Conclusion

SMS is an independent predictor of cardiac death in DCM patients and provides incremental prognostic value. SMS might have higher predictive value than LVEF for early cardiac death.

Association of Left Ventricular Systolic Function with Diagonal Branch Flow in Patients with First Anterior ST-Elevation Myocardial Infarction Treated with Primary Angioplasty

Background: There are few studies about the impact of diagonal branch blood flow on echocardiographic findings in patients with first acute anterior myocardial infarction undergoing primary angioplasty. Objectives: We aimed to compare left ventricular systolic function measures in patients with first acute anterior ST-segment elevation myocardial infarction (STEMI) treated with primary angioplasty based on diagonal branch blood flow after the procedure. Methods: This study was a single-center study that enrolled patients with their first acute anterior STEMI treated with primary angioplasty in our center between October 2020 and March 2021. Patients were divided into two groups: The patients with final thrombolysis in myocardial infarction (TIMI) flow III in diagonal (sufficient diagonal flow) and patients with final TIMI flow less than III in diagonal (insufficient diagonal flow) after the procedure. The left ventricular Wall-Motion Score Index (WMSI) and left ventricular ejection fraction (LVEF) were compared between the two groups. Results: A total of 107 patients with first anterior STEMI treated with primary PCI were enrolled in the present study, of which 13 patients (12.1%) had insufficient diagonal flow after primary coronary angioplasty. The LVEF was lower in patients with insufficient diagonal flow (32.92 ± 7.29% vs. 39 ± 8.68%, P = 0.018). Also, this group had higher LV WMSI (1.68 ± 0.28 vs. 1.49 ± 0.26, P = 0.029). Conclusions: The present study showed that in patients with first acute anterior STEMI undergoing primary angioplasty, insufficient diagonal branch flow after the procedure was associated with worse left ventricular systolic function and higher LV WMSI.

Evaluation of the Prognostic Role of the Wall Motion Score Index and the SYNTAX Score II in Patients with Acute Coronary Syndrome Following Percutaneous Coronary Intervention by Evaluation of Major Adverse Cardiovascular Events at 12-Month Follow-Up

Background

This study aimed to evaluate the wall motion score (WMS) index and the SYNTAX score II (SSII) in patients with acute coronary syndrome (ACS) following percutaneous coronary intervention (PCI) by evaluation of major adverse cardiovascular events (MACEs) at the 12-month follow-up at a single center.

Material/Methods

An observational study of 430 patients with ACS undergoing PCI at the Second Affiliated Hospital of Soochow University over a 1-year period was performed. Baseline data including WMS and SSII were recorded and compared with the rates of MACEs in the study group. WMS and SSII were stratified by the tercile from low to high.

Results

Both WMS and SSII were associated with the rates of MACEs (P<0.001 and P=0.003, respectively). The incidence of MACEs was positively correlated with terciles of the WMS and SSII groups (3.7% vs 1.6% vs 7.0% [P<0.001] and 2.6% vs 5.8% vs 11.6% [P<0.001], lowest to highest, respectively). Logistic regression analyses identified combined predictors for 12-month outcome, including WMS and SSII. The use of a model combining both scores yielded a higher predictive value (area under the curve [AUC]=0.78; 95% confidence interval [CI], 0.733–0.835; P<0.001) than the use of either score alone. Using WMSs alone, the AUC was 0.73 (95% CI, 0.660–0.793; P<0.001). Using SSII alone, the AUC was 0.71 (95% CI, 0.649–0.769; P<0.001).

Conclusions

This study showed that the combined methods of the WMS index and the SSII were predictive factors of MACEs in patients with ACS following PCI at the 12-month follow-up.

Partitioning risk factors for embolic stroke of undetermined source using exploratory factor analysis

Background

Embolic stroke of undetermined source (ESUS) accounts for up to 25% of strokes. Understanding risk factors associated with ESUS is important in reducing stroke burden worldwide. However, ESUS patients are younger and present with fewer traditional risk factors. Significant global variation in ESUS populations also exists making the clinical picture of this type of stroke unclear.

Methods and results

ESUS patients were pair matched for age, sex, and ethnicity with a group of all other strokes (both n = 331). Exploratory factor analysis was applied in both groups to 14 risk and clinical factors to identify latent factors. In ESUS patients, two latent factors emerged consisting primarily of heart-related variables such as left ventricular wall motion abnormalities, reduced ejection fraction, and increased left atrial volume index, as well as aortic arch atherosclerosis. This is in comparison to the all other strokes group, which was dominated by traditional stroke risk factors.

Conclusions

Our findings support the existence of a unique pattern of risk factors specific to ESUS. We show that LVWMA and corresponding changes in left heart function are a potential source of emboli in these patients. In addition, the clustering of aortic arch atherosclerosis with left heart factors suggests a causal link. Through the application of exploratory factor analysis, this work contributes to a further understanding of stroke mechanisms in ESUS.

Flow network tracking for spatiotemporal and periodic point matching: Applied to cardiac motion analysis

The accurate quantification of left ventricular (LV) deformation/strain shows significant promise for quantitatively assessing cardiac function for use in diagnosis and therapy planning. However, accurate estimation of the displacement of myocardial tissue and hence LV strain has been challenging due to a variety of issues, including those related to deriving tracking tokens from images and following tissue locations over the entire cardiac cycle. In this work, we propose a point matching scheme where correspondences are modeled as flow through a graphical network. Myocardial surface points are set up as nodes in the network and edges define neighborhood relationships temporally. The novelty lies in the constraints that are imposed on the matching scheme, which render the correspondences one-to-one through the entire cardiac cycle, and not just two consecutive frames. The constraints also encourage motion to be cyclic, which an important characteristic of LV motion. We validate our method by applying it to the estimation of quantitative LV displacement and strain estimation using 8 synthetic and 8 open-chested canine 4D echocardiographic image sequences, the latter with sonomicrometric crystals implanted on the LV wall. We were able to achieve excellent tracking accuracy on the synthetic dataset and observed a good correlation with crystal-based strains on the in-vivo data.

Assessment of LVEF using a new 16-segment wall motion score in echocardiography

Background

Simpson biplane method and 3D by transthoracic echocardiography (TTE), radionuclide angiography (RNA) and cardiac magnetic resonance imaging (CMR) are the most accepted techniques for left ventricular ejection fraction (LVEF) assessment. Wall motion score index (WMSI) by TTE is an accepted complement. However, the conversion from WMSI to LVEF is obtained through a regression equation, which may limit its use. In this retrospective study, we aimed to validate a new method to derive LVEF from the wall motion score in 95 patients.

Methods

The new score consisted of attributing a segmental EF to each LV segment based on the wall motion score and averaging all 16 segmental EF into a global LVEF. This segmental EF score was calculated on TTE in 95 patients, and RNA was used as the reference LVEF method. LVEF using the new segmental EF 15-40-65 score on TTE was compared to the reference methods using linear regression and Bland–Altman analyses.

Results

The median LVEF was 45% (interquartile range 32–53%; range from 15 to 65%). Our new segmental EF 15-40-65 score derived on TTE correlated strongly with RNA-LVEF (r = 0.97). Overall, the new score resulted in good agreement of LVEF compared to RNA (mean bias 0.61%). The standard deviations (s.d.s) of the distributions of inter-method difference for the comparison of the new score with RNA were 6.2%, indicating good precision.

Conclusion

LVEF assessment using segmental EF derived from the wall motion score applied to each of the 16 LV segments has excellent correlation and agreement with a reference method.

Superiority of wall motion score index over left ventricle ejection fraction in predicting cardiovascular events after an acute myocardial infarction

Background:

There are few data on the prognostic significance of the wall motion score index compared with left ventricle ejection fraction after an acute myocardial infarction. Our objective was to compare them after the hyperacute phase.

Methods:

Transthoracic echocardiograms were performed in 352 consecutive patients with myocardial infarction, after the first 48 hours of admission and before hospital discharge (median 56.3 hours (48.2–83.1)). We evaluated the ability of the wall motion score index and left ventricular ejection fraction to predict the combined endpoint (mortality and rehospitalization for heart failure) as a primary objective and the independent events of the combined endpoint as a secondary objective.

Results:

In 80.7% of patients, the wall motion score index was high despite having an ejection fraction >40%. No patient had an ejection fraction <55% with a normal index. After a follow-up of 30.5 months (24.2–49.5), both variables were predictors of the composite endpoint and all-cause mortality ( p<0.0001), although only the wall motion score index was a predictor of readmission for heart failure ( p=0.007). By multivariate analysis, a wall motion score index >1.8 proved to be the most powerful predictor of the composite endpoint (hazard ratio: 8.5; 95% confidence interval 3.7–18.8; p<0.0001). The superiority of the wall motion score index over ejection fraction was especially significant in patients with less myocardial damage (non-ST elevation myocardial infarction, or left ventricle ejection fraction >40%).

Conclusions:

Both variables provide important prognostic information after a myocardial infarction. Beyond the hyperacute phase, wall motion score index is a more powerful prognostic predictor, especially in subgroups with less myocardial damage.

Efficacy and safety of supramaximal titrated inhibition of renin-angiotensin-aldosterone system in idiopathic dilated cardiomyopathy

Aims

The optimal dosing strategies for blocking the renin‐angiotensin‐aldosterone system in idiopathic dilated cardiomyopathy (IDCM) are poorly known. We sought to determine the long‐term efficacy and safety of supramaximal titration of benazepril and valsartan in patients with IDCM.

Methods and results

480 patients with IDCM in New York Heart Association functional class II–IV and with left ventricular ejection fraction ≤35% were randomly assigned to extended‐release metoprolol (mean 152 mg/day, range 23.75–190), low‐dose benazepril (20 mg/day), low‐dose valsartan (160 mg/day), high‐dose benazepril (mean 69 mg/day, range 40–80), and high‐dose valsartan (mean 526 mg/day, range 320–640). After a median follow‐up of 4.2 years, high‐dose benazepril and valsartan, compared with their respective low dosages, resulted in 41% and 52% risk reduction in the primary endpoint of all‐cause death or admission for heart failure (P = 0.042 and 0.002), promoted functional improvement, and reversed remodelling as assessed by New York Heart Association classes, quality‐of‐life scores, and echocardiographic recording of left ventricular ejection fraction, left ventricular end‐diastolic volume, mitral regurgitation, and wall motion score index. Compared with metoprolol, high‐dose valsartan reduced risk for the primary endpoint by 46% (P = 0.006), whereas high‐dose benazepril and both low‐dose groups showed no significant difference. Major adverse events involved hypotension and renal impairment but were largely tolerated.

Conclusions

Supramaximal doses of benazepril and valsartan were well tolerated and produced extra benefit than their low dosages in clinical outcome and cardiac reverse remodelling in patients with IDCM and modest‐severe heart failure. ClinicalTrials.gov identifier: NCT01917149.

Effects of Everolimus-Eluting Stents on the Left Ventricular Systolic and Diastolic Functions

BACKGROUND

The drug-eluting stent (DES) decreases the rate of coronary restenosis and re-obstruction. The aim of this study was to assess prospectively the effectiveness of the new generation DES on the left ventricular (LV) systolic and diastolic functions in patients with isolated severe proximal left anterior descending (LAD) coronary artery stenosis.

METHODS

A prospective study was conducted on 50 patients with isolated severe proximal LAD stenosis. Successful percutaneous coronary intervention (PCI) with Everolimus-eluting stents was performed for the whole study population. All the patients underwent transthoracic echocardiography within 24 hours before and one month after PCI, and LV systolic and diastolic parameters were compared before and after PCI using the paired samples t-test.

RESULTS

The mean age of the study population was 57.68 ± 8.82 years. Within the study population, 26 (52%) patients were male and 24 (48%) were female. There was a significant 10.6% and 5.2% increase in the early diastolic mitral annular motion (e') and the LV ejection fraction following PCI, respectively (p value = 0.005 and p value = 0.044, respectively). Before PCI, wall motion abnormality was seen in 2.21 ± 2.91 segments, which significantly decreased to 1.49 ± 2.58 segments (p value = 0.04) after the procedure. Also, the wall motion score index was 1.18 ± 0.26 before PCI, which significantly decreased to 1.13 ± 0.23 after PCI (p value < 0.001). Also, there was a trend toward a higher ratio of transmitral peak early diastolic velocity to peak late diastolic velocity after PCI (p value = 0.068).

CONCLUSION

Our study showed that the use of the Everolimus-eluting stents improved the LV systolic and diastolic functions in patients with isolated severe LAD stenosis.

Left ventricular ejection fraction assessment by non-cardiologists from transverse views using a simplified wall motion score index

For the non-cardiologist emergency physician and intensivist, performing an accurate estimation of left ventricular ejection fraction (LVEF) is essential for the management of critically ill patients, such as patients presenting with shock, severe respiratory distress or chest pain. Our objective was to develop a semi-quantitative method to improve visual LVEF evaluation. A group of 12 sets of transthoracic echocardiograms with LVEF in the range of 18–64% were interpreted by 17 experienced observers (PRO) and 103 untrained observers or novices (NOV), without previous training in echocardiography. They were asked to assess LVEF by two different methods: i) visual estimation (VIS) by analysing the three classical left ventricle (LV) short-axis views (basal, midventricular and apical short-axis LV section) and ii) semi-quantitative evaluation (base, mid and apex (BMA)) of the same three short-axis views. The results for each of these two methods for both groups (PRO and NOV) were compared with LVEF obtained by radionuclide angiography. The semi-quantitative method (BMA) improved estimation of LVEF by PRO for moderate LV dysfunction (LVEF 30–49%) and normal LVEF. The visual estimate was better for lower LVEF (<30%). In the NOV group, the semi-quantitative method was better than than the visual one in the normal group and in half of the subjects in the moderate LV dysfunction (LVEF 30–49%) group. The visual estimate was better for the lower LVEF (ejection fraction <30%) group. In conclusion, semi-quantitative evaluation of LVEF gives an overall better assessment than VIS for PRO and untrained observers.

The assessment of relationship between fragmented QRS complex and left ventricular wall motion score index in patients with ST elevation myocardial infarction who underwent primary percutaneous coronary intervention

OBJECTIVES

Fragmented QRS (fQRS) has been found to be associated with high mortality and arrhythmic events in acute coronary syndromes. Regional systolic function using wall motion score index (WMSI) is an alternative to left ventricular ejection fraction (LVEF) for the assessment of left ventricular systolic function. The aim of this study was to investigate the relation between the presence of fQRS on admission electrocardiogram (ECG) and WMSI in ST elevation myocardial infarction (STEMI) underwent primary coronary intervention (PCI). The in-hospital and long-term prognostic significance of persistent fQRS was also evaluated.

METHODS

In this retrospective study, 542 patients with a diagnose of STEMI underwent primary PCI were included. Study patients were divided into two groups according to the presence (n = 153) or absence (n = 389) of a fQRS on admission ECG.

RESULTS

WMSI was found to be significantly higher in fQRS(+) group compared to the fQRS(-) group (P < 0.001). In multivariete analysis, WMSI was found to be an independent predictor of fQRS, and fQRS was inversely associated with LVEF. The in-hospital reinfarction (P = 0.003), MACE (P = 0.024), intraaortic balloon pump use (P = 0.014), and advanced heart failure (P < 0.001) were found to be significantly more frequent in the fQRS(+) group. The presence of fQRS on admission was found to be associated with an increase in long-term cardiovascular mortality (P = 0.028), and long-term all-cause mortality (P = 0.022).

CONCLUSION

WMSI was significantly related with the presence of the fQRS, which reflects the linking between impairment of regional left ventricular systolic function and the presence of severe myocardial injury in STEMI.

Dissociation of early shock in takotsubo cardiomyopathy from either right or left ventricular systolic dysfunction

BACKGROUND

Takotsubo cardiomyopathy (TTC) is often associated with hypotension and shock. However, development of hypotension/shock in TTC is not closely related to extent of left ventricular (LV) hypokinesis. We sought to determine whether additional right ventricular (RV) involvement in TTC might contribute to hypotension and shock development and thus to prolonged hospital stay (PHS).

METHODS

We evaluated 102 consecutive TTC patients with acute transthoracic echocardiography (TTE) to detect RV hypokinesis. Correlates of hypotension, shock and PHS were identified by univariate and multivariate analyses.

RESULTS

Of the 102 patients evaluated, 33% had RV hypokinesis but only 9% had extensive RV involvement. Within the first 24 hours of admission, severe hypotension (systolic blood pressure (SBP) ≤ 90 mmHg) occurred in 21% of the patients and shock (hypotension + peripheral organ hypo-perfusion) in 16.6% of cases. RV involvement was a univariate but not a multivariate correlate of either hypotension or shock and did not result in PHS. On the other hand, RV involvement predicted more extensive LV hypokinesis and LV systolic dysfunction.

CONCLUSIONS

In TTC, RV hypokinesis occurs in approximately 33% of cases and correlates with more severe LV wall motion abnormality but not with development of hypotension or shock. These data therefore reinforce previous findings that hypotension/shock in TTC are not purely by impaired cardiac output.

Role of echocardiography in the contemporary management of chronic heart failure

Echocardiography is an excellent noninvasive tool for the assessment of ventricular size and both systolic and diastolic function, and it is routinely used in patients with heart failure. This review will discuss the role of echocardiography in heart failure diagnosis, prognostic assessment and in the management of heart failure patients.

The prognostic importance of left ventricular function in patients with ST-segment elevation myocardial infarction: the HORIZONS-AMI trial

AIM

Left ventricular (LV) dysfunction during and after hospitalization for ST-segment elevation myocardial infarction (STEMI) is associated with increased mortality. Whether baseline LV dysfunction impacts STEMI outcomes is not well studied. Furthermore, whether bivalirudin and paclitaxel-eluting stents (PES) are beneficial in patients with LV dysfunction is unknown. We studied the impact of left ventricular ejection fraction (LVEF) on outcomes of patients with STEMI in the HORIZONS-AMI trial.

METHODS

LVEF was determined in 2648 (73.5%) of 3602 enrolled STEMI patients, who were divided into three groups according to LV function: (1) severely impaired (LVEF <40%); (2) moderately impaired (LVEF 40-50%); and (3) normal (LVEF ≥50%).

RESULTS

Compared to patients with normal LV function, those with severely impaired LVEF had higher 1-year rates of net adverse clinical events (27.1 vs. 14.2%, p<0.0001), major adverse cardiovascular events (20.7 vs. 9.5%, p<0.0001), cardiac death (10.6 vs. 1.2%, p<0.0001), and non-coronary artery bypass graft major bleeding (12.5 vs. 6.6%, p=0.001), differences which persisted after adjustment for baseline characteristics. Among patients with LVEF <40%, treatment with bivalirudin compared to heparin+GPIIb/IIIa inhibitors resulted in reduced 1-year mortality (5.8 vs. 18.3%, p=0.007). Patients with LVEF <40% receiving PES rather than bare metal stents had lower rates of 1-year ischaemia-driven target lesion revascularization (2.9 vs. 12.6%, p=0.02) and reinfarction (4.5 vs. 14.7%, p=0.03).

CONCLUSIONS

Among patients with STEMI undergoing primary percutaneous coronary intervention, adverse events are markedly increased in those with LVEF <40% during the index revascularization procedure. Nevertheless, these high-risk patients experience substantial clinical benefits from bivalirudin and PES.

Validation of a novel modified wall motion score for estimation of left ventricular ejection fraction in ischemic and non-ischemic cardiomyopathy

BACKGROUND

Visual determination of left ventricular ejection fraction (LVEF) by segmental scoring may be a practical alternative to volumetric analysis of cine magnetic resonance imaging (MRI). The accuracy and reproducibility of this approach for has not been described. The purpose of this study was to validate a novel segmental visual scoring method for LVEF estimation using cine MRI.

METHODS

362 patients with known or suspected cardiomyopathy were studied. A modified wall motion score (mWMS) was used to blindly score the wall motion of all cardiac segments from cine MRI imaging. The same datasets were subjected to blinded volumetric analysis using endocardial contour tracing. The population was then separated into a model cohort (N=181) and validation cohort (N=181), with the former used to derive a regression equation of mWMS versus true volumetric LVEF. The validation cohort was then used to test the accuracy of this regression model to estimate the true LVEF from a visually determined mWMS. Reproducibility testing of mWMS scoring was performed upon a randomly selected sample of 20 cases.

RESULTS

The regression equation relating mWMS to true LVEF in the model cohort was: LVEF=54.23-0.5761×mWMS. In the validation cohort this equation produced a strong correlation between mWMS-derived LVEF and true volumetric LVEF (r=0.89). Bland and Altman analysis showed no systematic bias in the LVEF estimated using the mWMS (-0.3231%, 95% limits of agreement -12.22% to 11.58%). Inter-observer and intra-observer reproducibility was excellent (r=0.93 and 0.97, respectively).

CONCLUSION

The mWMS is a practical tool for reporting regional wall motion and provides reproducible estimates of LVEF from cine MRI.

Global left ventricular longitudinal systolic strain for early risk assessment in patients with acute myocardial infarction treated with primary percutaneous intervention

BACKGROUND

Left ventricular systolic function is a key determinant of outcome after ST-segment elevation myocardial infarction (STEMI). The aim of this study was to study speckle-tracking global longitudinal strain (GLS) for early risk evaluation in STEMI and compare it with left ventricular ejection fraction (LVEF), wall motion score index (WMSI), and end-systolic volume index (ESVI).

METHODS

Five-hundred seventy-six patients underwent echocardiography ≤24 hours after primary percutaneous coronary intervention for STEMI. The end point was the composite of death, hospitalization with reinfarction, congestive heart failure, or stroke. Associations with outcome were assessed by multivariate Cox regression with adjustment for clinical parameters. Hazard ratios (HRs) for events within the first year are reported per absolute percentage GLS increase.

RESULTS

During a median follow-up period of 24 months, 162 patients experienced at least one event. GLS was associated with the composite end point (adjusted HR, 1.20; 95% confidence interval [CI], 1.12-1.29) and also when controlling for LVEF (adjusted HR, 1.17; 95% CI, 1.07-1.29) and ESVI (adjusted HR, 1.18; 95% CI, 1.08-1.28). Although WMSI was significantly associated with outcome beyond any association accounted for by GLS, a borderline significant association was found after controlling for WMSI (adjusted HR for GLS, 1.10; 95% CI, 1.00-1.21). When GLS or WMSI was known, there was no significant association between LVEF or ESVI and outcome.

CONCLUSIONS

In a large population of patients with STEMI, GLS and WMSI were comparable and both superior for early risk assessment compared with volume-based left ventricular function indicators such as LVEF and ESVI. Compared with WMSI, the advantage of GLS is the provision of a semiautomated quantitative measure.

Left ventricular morphology and function in diabetic and nondiabetic hemodialyzed patients

Morbidity in end-stage renal disease (ESRD) diabetic patients is worse than in patients without diabetes mellitus (DM). This study aims to compare clinical, laboratory, and echocardiographic features between the ESRD patients with and without DM. Fifty-eight ESRD patients on dialysis were prospectively divided into two groups according to the presence of DM. Demographic, clinical, laboratory, and echocardiographic features (ejection fraction and wall motion score index) were compared between the two groups. Overall, 20 out of 58 patients (37.8%) with ESRD had DM. There were no significant differences between the patients with DM and those without DM when it comes to age (60.6 ± 10.6 vs. 59.0 ± 10.6 years, P = 0.665), ejection fraction (52.6% ± 12.8% vs. 54.2% ± 12.8%, P = 0.59), and wall motion score index (1.21 ± 0.3 vs.1.15 ± 0.3, P = 0.37). In multivariant analysis of the interventricular septum, posterior wall thickness and left atrium size correlated positively with DM. There was also no statistical difference in myocardial perfusion disturbances on real-time contrast echocardiography between the groups with and without DM (12 (60%) patients vs. 14 patients (36.8%), P = 0.079). Among diabetics 77.8% had significant atherosclerotic changes, while in the group without DM, only 38.1%, P = 0.01. From the laboratory parameters ferritin and high-sensitivity C-reactive protein levels were significantly higher in the group with DM, P = 0.014 and P = 0.026, respectively. Patients with ESRD and DM have significantly bigger left atrial size, thicker left ventricular walls, and higher serum ferritin and high-sensitivity C-reactive protein levels than the patients without DM. The aforementioned features may be possible risk factors for the development of adverse cardiac events in patients on hemodialysis.

Global longitudinal strain by speckle tracking for infarct size estimation

AIMS

To assess the utility of speckle tracking global longitudinal systolic strain (GLS) compared with traditional echocardiographic indices including left ventricular ejection fraction (LVEF), wall motion score index (WMSI), and end-systolic volume index (ESVI), in estimating the infarct size (IS) following a ST-elevation myocardial infarction (STEMI).

METHODS AND RESULTS

The study includes 227 patients with STEMI and day 1 and day 30 echocardiograms, and myocardial perfusion imaging (MPI) only at day 30 to assess IS. IS was modelled by linear regression with echocardiographic parameters using MPI as reference. Resulting echocardiographic IS estimates were compared by ratios of standard deviations of model residuals (RSD). To estimate the resultant day 30 IS 1 day after a STEMI, GLS was more precise than LVEF (RSD: 0.91, P = 0.014) and ESVI (RSD: 0.88, P = 0.002), and comparable with WMSI (RSD 0.99, P = 0.86). To estimate IS from a day 30 echocardiogram, GLS was comparable with LVEF (RSD: 0.98, P = 0.68) and ESVI (RSD: 1.04, P = 0.40), but WMSI was more precise (RSD: 0.89, P = 0.006). Multiple linear regression revealed that on day 1 after STEMI, GLS significantly complemented the standard parameters separately (P-values all models <0.001) or combined [multivariable model: GLS (P = 0.001), WMSI (P = 0.03), LVEF (P = 0.40)]. On day 30, GLS significantly complemented LVEF and ESVI, but when WMSI was in the model, GLS's association with IS was not significant.

CONCLUSION

On day 1 after revascularization for STEMI, GLS contains additional information about final IS compared with standard echocardiographic systolic function indices. Studies are needed to clarify whether this has prognostic implications.

A comparison of visual and quantitative assessment of left ventricular ejection fraction by cardiac magnetic resonance

To determine the accuracy of visual analysis of left ventricular (LV) function in comparison with the accepted quantitative gold standard method, cardiac magnetic resonance (CMR). Cine CMR imaging was performed at 1.5 T on 44 patients with a range of ejection fractions (EF, 5-80%). Clinicians (n = 18) were asked to visually assess EF after sequentially being shown cine images of a four chamber (horizontal long axis; HLA), two chamber (vertical long axis; VLA) and a short axis stack (SAS) and results were compared to a commercially available analysis package. There were strong correlations between visual and quantitative assessment. However, the EF was underestimated in all categories (by 8.4% for HLA, 8.4% for HLA + VLA and 7.9% for HLA + VLA + SAS, P all < 0.01) and particularly underestimated in mild LV impairment (17.4%, P < 0.01), less so for moderate (4.9%) and not for severe impairment (1%). Assessing more than one view of the heart improved visual assessment of LV, EF, however, clinicians underestimated EF by 8.4% on average, with particular inaccuracy in those with mild dysfunction. Given the important clinical information provided by LV assessment, quantitative analysis is recommended for accurate assessment.

Ventricular-arterial uncoupling in heart failure with preserved ejection fraction after myocardial infarction in dogs - invasive versus echocardiographic evaluation

Background

Heart failure with preserved left ventricular ejection fraction and abnormal diastolic function is commonly observed after recovery from an acute myocardial infarction. The aim of this study was to investigate the physiopathology of heart failure with preserved ejection fraction in a model of healed myocardial infarction in dogs.

Methods

Echocardiography, levels of neurohormones and conductance catheter measurements of left ventricular pressure-volume relationships were obtained in 17 beagle dogs 2 months after a coronary artery ligation, and in 6 controls.

Results

Healed myocardial infarction was associated with preserved echocardiographic left ventricular ejection fraction (0.57 ± 0.01, mean ± SEM) and altered Doppler mitral indices of diastolic function. NT-proBNP was increased, aldosterone was decreased, and norepinephrine was unchanged. Invasive measurements showed a markedly decreased end-systolic elastance (2.1 ± 0.2 vs 6.1 ± 0.8, mmHg/ml, p < 0.001) and end-systolic elastance to effective arterial elastance ratio (0.6 ± 0.1 vs 1.4 ± 0.2, p < 0.001), with altered active relaxation (dP/dtmin -1992 ± 71 vs -2821 ± 305, mmHg/s, p < 0.01) but preserved left ventricular capacitance (70 ± 6 vs 61 ± 3, ml at 20 mmHg, p = NS) and stiffness constant. Among echocardiographic variables, the wall motion score index was the most reliable indicator of cardiac contractility while E', E/A and E'/A' were correlated to dP/dtmin.

Conclusions

In the canine model of healed myocardial infarction induced by coronary ligation, heart failure is essentially characterized by an altered contractility with left ventricular-arterial uncoupling despite vascular compensation rather than by abnormal diastolic function

Myocardial dysfunction in subarachnoid hemorrhage: prognostication by echo cardiography and cardiac enzymes. A prospective study

BACKGROUND

The myocardial dysfunction in nontraumatic sub-arachnoid hemorrhage (SAH) is not well understood. Borderline elevations of cardiac biomarkers, electrocardiographic repolarization abnormalities and systolic dysfunction have been reported but the clinical significance of these abnormalities is uncertain.

METHODS

Patients without history of cardiac disease were prospectively evaluated for cardiac dysfunction. Myocardial regional wall motion and left ventricular ejection fraction (LVEF) were serially studied by transthoracic echocardiogram along with cardiac enzymes.

RESULTS

The mean age of the study population was 53 years. Majority of the patients had aneurysms (N = 38). The mean LVEF was 55 +/- 15%. Eight patients had evidence of WMA, mostly global hypokinesia (63%). The mean LVEF of patients with WMA was significantly lower compared to those without WMA (p < 0.001) at day 0. Systolic function recovered in 25% of these patients. The mean value of troponin was significantly higher in those with WMA (p < 0.001) and mean GCS upon admission was significantly lower (p < 0.001). On multivariate analysis, WMA were associated with poor GCS (p < 0.01) and increased hospitalization (P < 0.01).

CONCLUSIONS

WMA with systolic dysfunction occurred in 20% of patients and recovered within 3 days in 25%. Patients with evidence of WMA had a significant myocardial dysfunction, higher troponin levels and poor GCS.

Acute effects of "delayed postconditioning" with periodic acceleration after asphyxia induced shock in pigs

Asphyxia cardiac arrest and shock are models for whole body ischemia reperfusion injury. Periodic acceleration (pGz) achieved by moving the body on a platform is a novel method for inducing pulsatile vascular shear stress and endogenous production of endothelial nitric oxide, prostaglandin E2, tissue plasminogen activator, and adrenomedullin. The aforementioned are cardioprotective during and after ischemia reperfusion injury. We investigated whether pGz, applied 15 min after return of spontaneous circulation (ROSC) would serve as an effective "delayed" post conditioning tactic to lessen acute reperfusion injury markers in a pediatric swine model of asphyxia induced shock. Asphyxia shock was induced in 20 swine weight 3.9 +/- 0.6 kg. Fifteen minutes after ROSC, the animals were randomized to receive conventional mechanical ventilation (CMV, [Control]) or CMV with pGz. All animals had ROSC and no significant differences in blood gases or hemodynamics after ROSC. pGz treated had significantly less myocardial dysfunction post resuscitation, (i.e. better % ejection fraction (EF), % fractional shortening (FS), and wall motion score index) and lower biochemical indices of reperfusion injury (lower TNF-alpha, IL-6, and Troponin I, and myeloperoxidase activity). Delayed postconditioning with pGz ameliorates acute post resuscitation reperfusion injury and improves myocardial dysfunction after asphyxia-induced shock.

Early uptake of 99mTc-C2A in the acute phase of myocardial infarction as a prognostic indicator for follow-up cardiac dysfunction

OBJECTIVE

The C2A domain of Synaptotagmin I is a molecular probe for the specific imaging of cell death. Here we test the hypothesis that the uptake of 99mTc-C2A in the acute phase of an infarction is associated with cardiac dysfunction in follow-ups.

METHODS

The left coronary artery was occluded in Sprague-Dawley rats for 0, 10, 20, and 30 min. 99mTc-C2A was injected intravenously at 2 h of reperfusion. Anterior planar images were acquired with one million counts on a gamma camera 3 h after injection. 99mTc-C2A uptake was calculated as the total counts in the left ventricle region minus blood pool signal. The in-vivo signal detected was correlated with wall motion score index at 1 and 3 weeks follow-ups measured by echocardiography.

RESULTS

99mTc-C2A uptake was higher with increased ischemic time (2244+/-852, 4054+/-1223, and 6178+/-1451 for 10, 20, and 30 min ischemia, analysis of variance P<0.001). A significant correlation was found between 99mTc-C2A uptake and wall motion score index at 1 week (R=0.800, P=0.0006) and 3 weeks (R=0.810, P=0.0008).

CONCLUSION

In this ischemia/reperfusion model, 99mTc-C2A uptake in the acute phase was associated with functional abnormality at 1 and 3 weeks. This demonstrates the potential diagnostic and prognostic value of 99mTc-C2A as a novel imaging agent.

Evaluation of acute coronary syndromes by cardiac magnetic resonance imaging

The use of cardiovascular magnetic resonance (CMR) imaging for the evaluation of patients with acute chest pain and acute coronary syndromes has great potential. The strength of CMR relies on its ability to provide information on anatomy, physiology, and function in a single scanning session in a noninvasive manner without the need for iodinated contrast, radiation, or the need to undergo invasive procedures. Specifically, with regard to imaging patients with acute chest pain and/or myocardial infarction (MI), CMR has the ability to qualitatively and quantitatively evaluate global and regional right and left ventricular systolic functions, myocardial edema, myocardial perfusion, and myocardial infarct size and transmurality/viability. This review will focus on CMR imaging for the following applications: (1) imaging for the evaluation of ventricular function and infarct size in patients with acute chest pain and/or acute MI, (2) for triage and prognosis of patients presenting to the emergency department with acute chest pain, (3) for evaluating patients after sustaining an acute MI, and (4) for stem cell research.

Non-selective cyclooxygenase inhibition before periodic acceleration (pGz) cardiopulmonary resuscitation (CPR) in a porcine model of ventricular fibrillation

Whole body periodic acceleration (pGz) along the spinal axis is a novel method of cardiopulmonary resuscitation (CPR). Oscillatory motion of the supine body in a horizontal fashion provides ventilation and blood flow to vital organs during cardiac arrest and pulsatile shear stress to the vascular endothelium. We previously showed in pigs that pGz-CPR affords better overall survival, post resuscitation myocardial function, and neurological outcomes compared to conventional chest compression CPR. pGz through pulsatile shear stress on the vascular endothelium elicits acute production of prostaglandins and endothelial-derived nitric oxide (eNO) in whole animal models and in vitro preparations. The salutary effects associated with pGz-CPR compared to chest compression CPR are in part related to endothelial-derived nitric oxide. Both eNO and prostaglandins are cardioprotective in ischemia reperfusion models. To differentiate between the roles of these mediators, indomethacin a non-selective cyclooxygenase inhibitor (COX) was used as a tool to investigate prostaglandin effects during pGz-CPR by acute outcomes of survival, cardioprotection and regional blood flows (RBF). Two groups of anesthetized, intubated pigs weighing 25-36kg were studied. Prior to electrical induction of ventricular fibrillation (VF) animals received equal volumes of either saline placebo Control (CONT) (n=9) or indomethacin (INDO), (n=8), (2mg/kg). After 3min of unsupported VF, both groups received 15min of pGz-CPR followed by pharmacologic and electrical attempts for resuscitation. Return of circulation (ROSC) to 3h occurred in (78%) in CONT and (63%) in INDO pretreated animals. There was no statistically significant difference in hemodynamics between groups at baseline or during the protocol. At baseline, INDO caused a decrease in brain RBF. Two hours after ROSC, INDO blunted the hyperemia response to brain and heart. Echocardiographic evidence of myocardial dysfunction was most notable for the INDO group in the wall motion score index (WMSI). After 3h of ROSC there was a 4-fold difference in both creatine phosphokinase (CPK) and Troponin I concentration between INDO and CONT. Therefore, non-specific acute inhibition of COX in part blunts the salutary effects of pGz-CPR. These data suggest that prostaglandins in part are involved in the cardio protection induced by pGz during CPR.

Periodic acceleration (pGz) CPR in a swine model of asphyxia induced cardiac arrest. Short-term hemodynamic comparisons

BACKGROUND

Asphyxia is one of the most common causes of pediatric cardiac arrest, and becoming a more frequently recognized cause in adults. Periodic acceleration (pGz) is a novel method of cardiopulmonary resuscitation (CPR). pGz is achieved by rapid motion of the supine body headward-footward that generates adequate perfusion and ventilation during cardiac arrest. In a swine ventricular fibrillation cardiac arrest model, pGz produced a higher return of spontaneous circulation (ROSC), superior neurological outcome, less echocardiography evidence of post resuscitation myocardial stunning, and decreased indices of tissue injury. In contrast to standard chest compression CPR, pGz does not produce rib fractures. We investigated the feasibility of pGz in severe asphyxia cardiac arrest and assessed whether beneficial effects seen in the VF model of cardiac arrest could be realized.

METHODS AND RESULTS

Sixteen swine weight 4+/-1 kg were anesthetized, tracheally intubated, and instrumented to measure, hemodynamics and echocardiography. Asphyxia was induced by occlusion of the tracheal tube. After loss of aortic pulsations (median time 10 min) animals were observed for three additional minutes following which all were in cardiac arrest. The animals were then randomized to receive 10 min of pGz or standard chest compression ventilation performed with a commercial device (Thumper). A single dose of epinephrine (adrenaline) and sodium bicarbonate were given and defibrillation attempted if appropriate for a maximum of 10 min. Both groups received fractional inspired O2 concentration of 100% during CPR and after resuscitation. Four animals in each group (50%) had an initial ROSC, however only two of the four initial survivors remained alive 3h after ROSC. There were no significant differences in blood pressure, coronary perfusion pressure during CPR and after early ROSC between groups. pGz treated animals had significantly lower pulmonary artery pressure; 20+/-4 mmHg compared to Thumper 46+/-5 mmHg, 30 min after ROSC (p<0.01). Surviving animals in both groups had severe myocardial dysfunction at 30 min after ROSC. At necropsy, 25% of the Thumper treated animals had rib fractures, while none occurred in the pGz group.

CONCLUSIONS

In a lethal model of asphyxia cardiac arrest, pGz is equivalent to standard CPR, with respect to acute outcomes and resuscitation survival rates but is associated with significantly lower pulmonary artery pressures and does not produce traumatic rib fractures.

Skin blood flow and its oscillatory components in patients with acute myocardial infarction

BACKGROUND/AIMS

Laser Doppler flowmetry (LDF) was used to determine the influence of acute myocardial infarction (AMI) and of successful reperfusion treatment on basal skin blood flow and its oscillatory components.

METHODS

Skin LDF was performed on all extremities in 58 patients 4-9 days after AMI (Killip class I), and in 71 healthy age- and sex-matched controls. Wavelet analysis was applied to evaluate oscillatory components within the interval 0.005-2 Hz.

RESULTS

AMI patients had reduced mean flow (p < 0.01) and oscillatory components (p < 0.04) in all extremities. Reperfused (n = 40), compared to nonreperfused (n = 18), patients had higher mean flow and total spectral amplitude at all recording points. The difference was statistically significant only in legs (group median LDF in the left leg was 9.68 AU for reperfused and 5.71 AU for nonreperfused patients, p < 0.04, and 11.47 and 4.24 AU in the right leg, p < 0.01). Reperfused patients had significantly higher total spectral amplitude in both legs (p < 0.04).

CONCLUSIONS

In AMI patients, reduced skin blood flow and its oscillatory components may reflect ongoing neurohumoral activation despite absence of clinically apparent heart failure. The reduction of blood flow and its oscillatory components was larger in nonreperfused AMI patients, although they had a comparable left ventricular function.

Prevalence and Prognostic Significance of Wall-Motion Abnormalities in Adults Without Clinically Recognized Cardiovascular Disease

Background— Left ventricular wall motion (WM) abnormalities have recognized prognostic significance in patients with coronary or other heart diseases; however, whether abnormal WM predicts adverse events in adults without overt cardiovascular disease has not been assessed. Our objective was to determine whether echocardiographic WM abnormalities predict subsequent cardiovascular events in a population-based sample.

Methods and Results— Participants (n=2864, mean age 60±8 years, 64% women) without clinically evident cardiovascular disease in the second Strong Heart Study examination who had complete echocardiographic WM assessment were studied. Echocardiographic assessment revealed that 5% of participants (n=140) had focal hypokinesia, and 1.5% (n=42) had WM abnormalities. Relationships between WM abnormalities and fatal and nonfatal cardiovascular events (including myocardial infarction, stroke, coronary artery disease, and heart failure; n=554) and cardiovascular death (n=182) during 8±2 years follow-up were examined. In Cox regression, after adjustment for age, gender, waist/hip ratio, systolic blood pressure, and diabetes mellitus, segmental WM abnormalities were associated with a 2.5-fold higher risk of cardiovascular events and a 2.6-fold higher risk of cardiovascular death (both P <0.0001). In similar multivariable models, global WM abnormalities were associated with a 2.4-fold higher risk of cardiovascular events ( P =0.001) and a 3.4-fold higher risk of cardiovascular death ( P =0.003).

Conclusions— Echocardiographic left ventricular WM abnormalities in adults without overt cardiovascular disease are associated with 2.4- to 3.4-fold higher risks of cardiovascular morbidity and mortality, independent of established risk factors.

Relationship between regional and global left ventricular systolic and diastolic function in patients with coronary artery disease assessed by strain rate imaging

BACKGROUND

The relationship between regional and global left ventricular function has not been evaluated. The present study aimed to assess whether regional myocardial contraction and relaxation reflect global left ventricular systolic and early diastolic function, respectively.

METHODS AND RESULTS

The study involved 45 patients with coronary artery disease (CAD). Conventional echocardiography was performed, and segmental peak strain rate (SR) in the systole (S(SR)) and early diastole (E(SR)) were obtained from tissue Doppler imaging in each of 18 segments of the left ventricular myocardium from the apical views. The E(SR) was significantly correlated with S(SR) in all studied segments (r=0.55, p<0.0001). The average values of SR indices in each patient were defined as S(SR) index and E(SR) index, which were derived by dividing the summed value of the S(SR) or E(SR) by the number of respective assessable segments. A significant positive relationship was observed between the S(SR) index and left ventricular ejection fraction (r=0.85, p<0.0001). Also, there was a positive correlation between the E(SR) index and mitral flow E (r=0.68, p<0.0001).

CONCLUSIONS

Regional myocardial contraction and relaxation, as assessed by SR imaging, were closely related in patients with CAD. Furthermore, regional myocardial contraction and relaxation are important factors affecting global left ventricular systolic and early diastolic function.

Epidemiology of heart failure and left ventricular dysfunction after acute myocardial infarction

The development of heart failure and/or left ventricular systolic dysfunction has long been regarded as an ominous complication, significantly increasing the morbidity and short- and long-term mortality of survivors of acute myocardial infarction. Although the incidence of heart failure after myocardial infarction has fallen over the last few decades, it remains common, complicating up to 45% of infarcts. Moreover, up to 60% of myocardial infarcts will result in left ventricular systolic dysfunction, depending on the exact definition used. Those at greatest risk of developing heart failure are the elderly, females, and those with prior myocardial infarction. Advances in the management of acute myocardial infarction have led to reduced in-hospital mortality (even when complicated by heart failure), but longer-term mortality remains high in these patients.

Comparison of Regional Versus Global Assessment of Left Ventricular Function in Patients with Left Ventricular Dysfunction, Heart Failure, or Both After Myocardial Infarction: The Valsartan in Acute Myocardial Infarction Echocardiographic Study

BACKGROUND

Left ventricular (LV) ejection fraction (EF) and wall-motion index (WMI) have both been shown to be independent predictors of outcome after myocardial infarction (MI).

OBJECTIVES

We sought to determine whether these two measurements of LV systolic function provide similar or complementary information about prognosis after MI.

METHODS

Echocardiography was performed in 610 patients with LV dysfunction, heart failure, or both after MI enrolled in the Valsartan in Acute MI trial. LVEF was estimated by biplane Simpson's rule, and WMI was assessed using a 16-segment model in 502 patients with echocardiograms of sufficient quality for wall-motion assessment.

RESULTS

Both LVEF and WMI were independent predictors of adverse outcome after MI. LVEF conferred no additional prognostic information in multivariable analysis including WMI (P = .39) or number of affected segments (P = .53), whereas WMI (P = .02) and total number of affected segments (P = .006) remained significant even when adjusting for LVEF.

CONCLUSIONS

Assessment of regional dysfunction by WMI or the number of affected segments has slightly more prognostic value than LVEF in patients with LV dysfunction, heart failure, or both after MI. Regional assessment might be a more sensitive predictor of outcome than global assessment in patients with acute MI.

Wall motion score index and ejection fraction for risk stratification after acute myocardial infarction

BACKGROUND

The prognostic importance of regional systolic function, as assessed by wall motion score index (WMSI), compared with global function, as assessed by left ventricular ejection fraction (LVEF), has not been assessed in large populations after acute myocardial infarction.

METHODS

Echocardiograms, including the assessment of WMSI and LVEF, were performed in 767 patients with acute myocardial infarction at a median of 1 day (25th and 75th percentiles 0-2 days) after admission. Patients were followed for a median of 19 months (range 12-28 months). Cox proportional hazards models were constructed for the primary study end point (all-cause mortality) and for a secondary end point (hospitalization for congestive heart failure).

RESULTS

During follow-up (median 40 months; range 32-50 months), 216 patients died and 54 patients were hospitalized for congestive heart failure. By univariate analysis, both LVEF (P < .0001) and WMSI (P < .0001) were powerful predictors of all-cause mortality. By a forward conditional Cox model, WMSI proved to be an independent predictor of death (hazard ratio 1.15 per 0.2-unit increase, 95% CI 1.10-1.21, P < .0001). When WMSI was included in the model, LVEF did not provide additional prognostic information (P = .77). Wall motion score index also proved to be an independent predictor of hospitalization for congestive heart failure (hazard ratio 1.21 per 0.2-unit increase, 95% CI 1.07-1.37, P = .002), whereas LVEF did not (P = .56).

CONCLUSION

Both LVEF and WMSI provide powerful prognostic information after acute myocardial infarction; however, the predictive power of WMSI is greater.

Serological evidence of altered collagen homeostasis reflects early ventricular remodeling following acute myocardial infarction

BACKGROUND

Infarct expansion characterises early ventricular remodeling following myocardial infarction (AMI) and is a product of the balance between collagen degradation and synthesis. Serological markers of collagen turnover may help in predicting those at risk of remodeling. C-propeptide for type-I collagen (PICP) and C-telopeptide for type-I collagen (CITP) are markers of collagen synthesis and degradation, respectively.

METHODS

Fifty-one patients with AMI were recruited and dichotomised by echocardiographic wall motion index (WMI). Sequential measurements of plasma PICP and CITP were correlated to this and other echocardiographic variables of remodeling.

RESULTS

Twenty-three normal WMI, 28 abnormal WMI. Both groups showed increases in PICP and CITP over time. However, mean admission CITP higher in abnormal WMI group, 4.5 vs. 3.1 ng/ml (p<0.05) as was peak, 6.3 vs. 4.8 ng/ml (p<0.05). Conversely, admission PICP was lower in abnormal WMI group 114 vs. 143 ng/ml (p<0.05). Admission CITP correlated with WMI, r=0.53, p<0.001. CITP>3.2 ng/ml (normal mean+2S.D.) had 74% positive predictive value for abnormal WMI, negative predictive value 65%. Admission CITP negatively correlated with mitral deceleration time (Dt), r=-0.38, p=0.01. CITP>3.2 was associated with lower Dt-183 vs. 221 ms, p<0.05.

CONCLUSION

There is serological evidence of sequential increases in both collagen synthesis and degradation following AMI. However, the balance between these differs in patients who undergo remodeling, manifested by abnormal WMI and reduced Dt, compared to those with no evidence. They have relatively increased degradation and reduced synthesis, favouring net collagen breakdown. These changes occur early with evidence of increased breakdown on admission predicting early remodeling and support the role of serological markers to identify patients at risk of this.

Visually estimated left ventricular ejection fraction by echocardiography is closely correlated with formal quantitative methods

BACKGROUND

Simpson ejection fraction, wall motion score index, atrioventricular (AV) plane displacement and fractional shortening are all established formal echocardiographic methods for the assessment of left ventricular systolic function. Visually estimated (eyeballing) ejection fraction may be considered somewhat more subjective, although shown to correlate well with radionuclide ventriculography. We aimed to explore if echocardiographic eyeballing ejection fraction is comparable to formal methods for the evaluation of left ventricular systolic function.

METHODS

We assessed 89 consecutive patients after myocardial infarction or before coronary angiography. Eyeballing ejection fraction and wall motion score index were evaluated in the long-axis, short-axis and apical four- and two-chamber views. Simpson ejection fraction and AV plane displacement were assessed in the apical views. Fractional shortening was measured in the parasternal long-axis view. The respective systolic function measurements were in each patient made at different time points by a single investigator, masked to prior results.

RESULTS

All formal methods correlated significantly with eyeballing ejection fraction (p<0.001): AV plane displacement, R=0.647; FS, R=0.684; four-chamber Simpson ejection fraction, R=0.857; biplane Simpson ejection fraction, R=0.898; and wall motion score index, R=0.919.

CONCLUSION

Eyeballing ejection fraction correlated closely with all formal methods and the correlation coefficient improved with the reliability of the formal method. This finding is in concordance with prior studies, indicating that eyeballing ejection fraction may be the most accurate echocardiographic method for the assessment of left ventricular systolic function. Since it is readily and quickly performed, eyeballing ejection fraction could be used for routine echocardiography instead of formal methods.