Left ventricular remodeling after anterior wall acute myocardial infarction in modern clinical practice (from the REmodelage VEntriculaire [REVE] study group)

Relation of growth-differentiation factor 15 to left ventricular remodeling in ST-segment elevation myocardial infarction

The development of left ventricular remodeling (LVR) after myocardial infarction is associated with a high risk of heart failure and death. LVR is difficult to predict, and limited information is available on the association of cardiac biomarkers and LVR. Growth-differentiation factor-15 (GDF-15) is induced during heart failure development and, in animals models, might influence the different processes involved in cardiac remodeling. The aim of the present investigation was to assess the association between the serum levels of GDF-15 within the first 24 hours of ST-segment elevation myocardial infarction and the development of subsequent LVR at 12 months of follow-up. This prospective study included 97 patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention. Echocardiography was performed in all patients within the first 96 hours of admission and at 12 months of follow-up. LVR was defined as a >20% increase in the left ventricular end-diastolic volume at 12 months of follow-up compared to baseline. Blood samples for the determination of GDF-15 and brain natriuretic peptide were obtained within the first 24 hours after symptom onset. According to the pre-established criteria, 21 patients (22%) had LVR. Patients with LVR had greater levels of GDF-15 at study entry (median 3,439 pg/ml, interquartile range 2,391 to 6,168 vs median 1998 pg/ml, interquartile range 1,204 to 3,067, respectively; p <0.001). Multivariate analysis showed that GDF-15 (odds ratio 10.1, 95% confidence interval 2.5 to 40.1, p <0.001) and treatment with angiotensin-converting enzyme inhibitors (odds ratio 3.9, 95% confidence interval 1.2 to 12.3, p <0.01) were independents predictors of LVR. Receiving operating characteristics analysis showed an area under the curve of 0.77 for GDF-15 (95% confidence interval 0.67 to 0.84, p <0.001). In conclusion, the results of the present study have identified GDF-15 as an independent marker of LVR in patients with ST-segment elevation myocardial infarction.

Usefulness of satisfactory control of low-density lipoprotein cholesterol to predict left ventricular remodeling after a first ST-elevation myocardial infarction successfully reperfused

Left ventricular (LV) remodeling represents an important determinant in the progression to heart failure in patients after myocardial infarction. The aim of the present study was to evaluate in patients with first ST-segment elevation acute myocardial infarction who were successfully and completely reperfused whether the control of cholesterol is predictive of LV remodeling. A total of 109 patients referred to a coronary care unit for first ST-segment elevation myocardial infarction were analyzed. According to the change in indexed LV end-diastolic volume detected at follow-up visits, patients were divided into nonremodeling (n = 79) and remodeling (n = 30) groups. At coronary care unit admission, the prevalence of cardiovascular risk factors was similar in the 2 groups. Low-density lipoprotein (LDL) cholesterol values were used as criteria for cholesterol control. At follow-up visits, the prevalence of patients with target levels of plasma LDL cholesterol was lower in the remodeling compared to the nonremodeling group (67% and 91%, respectively, p <0.01). After adjusting for age, gender, baseline LV ejection fraction, baseline indexed LV end-diastolic volume, hypertension, diabetes, obesity, smoking status, time from acute event, drugs (β blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, calcium channel blockers, and statins), wall motion score index, and troponin levels, logistic regression analysis showed that patients with nontarget LDL cholesterol values at follow-up were significantly more likely to show cardiac remodeling (odds ratio 22.3, 95% confidence interval 2.91 to 171.9, p = 0.003). In conclusion, the present study shows that unsatisfactory control of LDL cholesterol independently predicts LV remodeling in patients with first ST-segment elevation myocardial infarction.

Predictive value of ischemic mitral regurgitation during the acute phase of ST elevation myocardial infarction treated with primary coronary intervention for left ventricular remodeling in long-term follow-up

Reperfusion therapy, mainly primary percutaneous coronary intervention (PCI), has improved survival and lowered complication rate in patients with ST elevation myocardial infarction (STEMI). Nevertheless, some patients develop left ventricular remodeling (LVR) during long-term follow-up.

AIMS

To assess the incidence of ischemic mitral regurgitation (MR) in the acute phase of STEMI treated with primary PCI. To assess prognostic value of MR during acute STEMI for prediction of LVR during long-term follow-up.

METHODS

This is a prospective, single-center study in 83 patients with the first STEMI. Inclusion criteria were as follows: time from symptom onset to PCI less than 12 h and successful restoration of blood flow (thrombolysis in myocardial infarction 3) in the infarct-related coronary artery. Transthoracic echocardiography was performed at discharge and 6 months after the MI.

RESULTS

At hospital discharge, ischemic MR was found in 35 (42%) patients. At 6 months follow-up, LVR was present in 21 (25%) patients. Univariate analysis revealed that remodeling could be predicted by age, weight, treatment with abciximab, left ventricular ejection fraction (LVEF), leaflets coaptation, coaptation height, tenting area, presence of MR, degree of MR. The best multivariate logistic regression model for remodeling prediction at 6 months was combination of ischemic MR degree (odds ratio (OR)=14.5; 95% confidence interval (CI): 3.89-54.0, P<0.00005), abciximab therapy (OR=0.09; 95% CI: 0.01-0.84, P<0.03) and LVEF (OR=0.89; 95% CI: 0.81-0.99, P<0.03).

CONCLUSION

Ischemic MR in STEMI is frequent, even despite effective primary PCI. The regurgitation grade and lower LVEF assessed at hospital discharge and lack of abciximab administration could predict development of LVR at 6 months.

The effects of spironolactone on atrial remodeling in patients with preserved left ventricular function after an acute myocardial infarction: a randomized follow-up study

OBJECTIVES

Atrial remodeling is an important part of cardiac remodeling after acute myocardial infarction (AMI). The aim of this study was to evaluate the effect of spironolactone on atria in patients with preserved left ventricular (LV) functions after AMI by using two-dimensional and tissue Doppler imaging techniques (TDI).

METHODS

The study consisted of 110 patients with AMI, successfully revascularized with percutaneous coronary intervention, ejection fraction greater than or equal to 40%, and Killip class I-II. Patients were randomized into two groups: conventional therapy (n=55) and additional spironolactone of 25 mg/day with standard conventional therapy (n=55). Echocardiography was performed in the first 48-72 h of AMI and during 6 months of follow-up. Left atrial volume index and emptying fraction were obtained. The peak regional atrial contraction velocity, the time between the onset of p-wave on the monitor ECG and the onset, peak, and the end (TE) of the atrial contraction wave on the tissue Doppler technique curve were measured.

RESULTS

The left atrial volume index and left atrium (LA) dimensions did not significantly change in either group. In the spironolactone group, left atrial emptying fraction increased compared with both baseline value (from 53.0 ± 0.16 to 57.0 ± 0.13 P=0.011) and conventional therapy group (from 50.0 ± 0.17 to 47.0 ± 0.16, P=0.013). The atrial contraction velocity did not change but the LA-TE, interatrial septum-TE, and right atrium-TE were prolonged in the conventional therapy group.

CONCLUSION

Additional spironolactone therapy provided a little benefit on LA remodeling and atrial electromechanic properties in patients with AMI and preserved LV functions.

Beneficial effect of ischemic preconditioning on post-infarction left ventricular remodeling and global left ventricular function

BACKGROUND

Preinfarction angina (PA) is a clinical analogue of ischemic preconditioning that improves postinfarct prognosis. Data concerning the association of PA with post infarction left ventricular (LV) remodeling and LV diastolic function are limited. We aimed to evaluate this association in patients with acute myocardial infarction (AMI) in the modern clinical era of widespread use of revascularization and antiremodeling medical treatment.

METHODS

We studied 53 patients with anterior AMI who underwent complete reperfusion and received up to date antiremodeling medical treatment. LV remodeling, systolic and diastolic function were assessed using 2D echocardiography at baseline and 6 at months follow-up. Patients were divided into two groups regarding the presence or absence of PA.

RESULTS

LV remodeling at follow-up was less frequent in the PA group (25 vs. 55 %, P<.05). Patients with PA had lower end-systolic volume index at baseline and follow up (24.1±6 vs. 30.1±14 ml/m(2), P<.001 and 25.3±8 vs. 35.6±2 ml/m(2), P=.001 respectively). Additionally at 6 months, they had better LV ejection fraction (52.1±9 vs. 42.9±10 %, P=.002) and exhibited improved diastolic filling as reflected by mitral E/e' (14.6±5 vs. 18.8±8, P=.05).

CONCLUSIONS

Ischemic preconditioning in the form of PA promotes better LV systolic and diastolic function in the mid-term and is associated with less postinfarct LV remodeling in this specific study population. The results of the study underline the possible need for further risk stratification of AMI patients regarding the absence of PA.

Cardiovascular proteomics: translational studies to develop novel biomarkers in heart failure and left ventricular remodeling

Heart failure (HF) remains a severe disease with a poor prognosis. HF biomarkers may include demographic features, cardiac imaging, or genetic polymorphisms but this term is commonly applied to circulating serum or plasma analytes. Biomarkers may have at least three clinical uses in the context of HF: diagnosis, risk stratification, and guidance in the selection of therapy. Proteomic studies on HF biomarkers can be designed as case/control using clinical endpoints; alternatively, left ventricular remodeling can be used as a surrogate endpoint. The type of samples (tissue, cells, serum or plasma) used for proteomic analysis is a key factor in the research of biomarkers. Since the final aim is the discovery of circulating biomarkers, and since plasma and serum samples are easily accessible, proteomic analysis is frequently used for blood samples. However, standardization of sampling and access to low-abundance proteins remains problematic. Although, proteomics is playing a major role in the discovery phase of biomarkers, validation in independent populations is necessary by using more specific methods. The knowledge of new HF biomarkers may allow a more personalized medicine in the future.

Cardiac imaging after myocardial infarction

After myocardial infarction, optimal clinical management depends critically on cardiac imaging. Remodelling and heart failure, presence of inducible ischaemia, presence of dysfunctional viable myocardium, future risk of adverse events including risk of ventricular arrhythmias, need for anticoagulation, and other questions should be addressed by cardiac imaging. Strengths and weaknesses, recent developments, choice, and timing of the different non-invasive techniques are reviewed for this frequent clinical scenario.

Late recovery in left ventricular systolic function after discharge of patients with a first anterior myocardial infarction

BACKGROUND

Left ventricular systolic function is a useful indicator of in-hospital prognosis in patients with acute myocardial infarction. For long-term risk stratification, however, the variable degree of recovery that may occur during the ensuing period has also to be taken into account.

AIMS

To analyse the prevalence, time course, determinants and correlates of late left ventricular function recovery after myocardial infarction, from hospital discharge to 1-year follow-up, using systematic serial assessment of left ventricular function.

METHODS

Data from 512 patients with a first anterior myocardial infarction included in two prospective studies on left ventricular remodelling (REVE and REVE-2) were analysed. Serial echocardiographic studies were performed before discharge, at 3 months and at 1 year after myocardial infarction. Left ventricular volumes, ejection fraction, and Wall Motion Score Index were determined at a core echocardiographic laboratory.

RESULTS

In both cohorts, there was a significant decrease in Wall Motion Score Index between discharge and 1 year (from 1.87 ± 0.15 to 1.71 ± 0.21 [P<0.0001] in REVE; and from 1.91 ± 0.15 to 1.64 ± 0.28 [P<0.0001] in REVE-2), indicating an improvement in systolic function. Left ventricular ejection fraction increased from 49.6 ± 9.5% at baseline to 51.5 ± 9.5% at 1 year in REVE (P<0.008), and from 49.8 ± 8.3% to 55.5 ± 9.8% in REVE-2 (P<0.0001). Most of the recovery occurred within the first 3 months after discharge, but there was still significant recovery between 3 months and 1 year. Peak creatine kinase was the sole variable independently associated with left ventricular function recovery in both studies. Patients with no or minimal function recovery had the greater increase in left ventricular volumes at 1 year.

CONCLUSIONS

Late recovery in left ventricular function is common after discharge in patients with acute myocardial infarction. Further research is needed to identify new parameters that may help to predict this favourable outcome.

Left ventricular remodeling in the elderly with acute anterior myocardial infarction treated with primary coronary intervention

We compared left ventricular (LV) remodeling following a first time acute anterior ST-elevation myocardial infarction (aSTEMI) treated with primary coronary intervention (pPCI) in different age groups. A total of 116 patients, 61 aged <65 and 55 aged >or=65 years, who survived after a recent aSTEMI treated with pPCI, underwent dobutamine stress-echocardiography (DSE) and non-invasive measurement of left anterior descending coronary artery flow reserve (CFR) during intravenous adenosine infusion. Baseline LV dimensions and systolic function were similar between the two groups; wall motion score indices during all DSE stages and CFR were also similar. In both groups, the LV ejection fraction was positively affected by the presence of viability in the necrosis area and by a higher CFR, but negatively influenced by viability in a remote area, an indirect sign of an extensive infarction size. This study demonstrates that PCI in the geriatric population with aSTEMI is as equally effective as in younger subjects, in terms of LV remodeling and function.

Decreased serine207 phosphorylation of troponin T as a biomarker for left ventricular remodelling after myocardial infarction

AIMS

Chronic heart failure following myocardial infarction (MI) is characterized by progressive left ventricular remodelling (LVR). Despite significant improvements in MI management, LVR remains a frequent complication. Although several risk factors have been identified, such as infarct size, LVR is difficult to predict in clinical practice.

METHODS AND RESULTS

Using a rat model of MI and phosphoproteomic technology, we discovered that remodelling is associated with decreased levels of myocardial and plasma serine(208)-phosphorylated troponin T (TnT). To confirm the association in human plasma, we developed new specific polyclonal antibodies against human/rat serine(207/208)-phosphorylated TnT and tested plasma obtained in the first week after MI from patients with low, intermediate, and high remodelling a year later. We observed a significant decrease of serine(207)-phosphorylated TnT and of the serine(207)-phosphorylated TnT/total TnT ratio in those with intermediate or high LVR. These differences remained statistically significant when adjusted for other determinants of LVR. In contrast, baseline B-type natriuretic peptide levels were not associated with LVR.

CONCLUSION

The level of circulating phosphorylated TnT could be a new biomarker of LVR.

Neopterin predicts left ventricular remodeling in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

BACKGROUND

Left ventricle remodeling (LVR) is a relatively common and unfavourable event occurring after acute myocardial infarction. A link exists between inflammation and LVR. Neopterin, a marker of inflammation and macrophage activation, is a predictor of left ventricular dysfunction in patients with coronary artery disease. We therefore sought to assess whether both neopterin and brain natriuretic peptide (BNP), a marker of LV dysfunction and patient outcome, correlate with LVR in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

We prospectively assessed 108 STEMI patients (age 64 + or - 11 years; 85% male) undergoing primary percutaneous coronary intervention (PCI) who were assessed echocardiographycally assessment was performed at 96 + or - 10h after the onset of symptoms and 12 month after STEMI. LVR was defined as >20% increase in LV end-diastolic volume at 12 months of follow-up compared to baseline. Neopterin and BNP serum concentrations were measured immediately before primary PCI.

RESULTS

At 1 year, 21 patients (19%) showed LVR and 87 (81%) had no LVR. Patients with LVR had higher levels of neopterin at study entry (7.45 + or - 1.04 vs 5.19 + or - 1.39 nmol/L; p<0.001). After adjustment for relevant confounders, neopterin levels were found to be an independent predictor of LVR (OR ranging from [3.10, CI 95% 1.928-4.990, p<0.001] to [3.32, CI 95% 1.999-5.532, p<0.001]). ROC analysis showed an area under the curve of 0.901 for neopterin (CI 95% 0.84-0.96, p<0.0001) compared to 0.579 for BNP (CI 95% 0.409-0.748) regarding LVR.

CONCLUSIONS

In STEMI patients undergoing primary PCI, high neopterin levels - but not BNP - predict LVR at 1-year follow-up.

Attenuation of left ventricular adverse remodeling with epicardial patching after myocardial infarction

BACKGROUND

Previous studies suggested that epicardial patch applied to the infarcted site after acute myocardial infarction (MI) can alleviate left ventricular (LV) remodeling and improve cardiac performance; however, the effects of regional epicardial patch on chronic phase of LV remodeling remain unclear.

METHODS AND RESULTS

We studied 20 pigs with MI induced by distal embolization and impaired LV ejection fraction (LVEF < 45%) as detected by gadolinium-enhanced cardiac magnetic resonance imaging (MRI). Eight weeks post-MI, all animal underwent open chest procedure for sham surgery (control, n = 12) or patch implantation over the infarcted lateral LV wall (patch group, n = 12). In the patch group, +dP/dt increased and LV end-diastolic pressure decreased at 20 weeks compared with immediately post-MI and at 8 weeks (P < .05), but not in the control group (P > .05). As determined by cardiac MRI, LV end-diastolic and end-systolic volumes increased at 20 weeks compared with 8 weeks in both groups (P < .05). However, the increase in LV end-diastolic volume (+14.1 +/- 1.8% vs. +6.6 +/- 2.1%, P = .015) and LV end-systolic volume (+12.1 +/- 2.4% vs. -4.7 +/- 3.7%, P = .0015) were significantly greater in the control group compared with the patch group. Furthermore, the percentage increase in LVEF (+17.3 +/- 4.9% vs. +4.1 +/- 3.9%, P = .048) from 8 to 20 weeks was significantly greater in the patch group compared with the control group. Histological examination showed that LV wall thickness at the infarct region and adjacent peri-infarct regions were significantly greater in the patch group compared with the control group (P < .05).

CONCLUSION

Regional application of a simple, passive synthetic epicardial patch increased LV wall thickness at the infarct region, attenuated LV dilation, and improved LVEF and +dP/dt in a large animal model of MI.

Deep plasma proteomic analysis of patients with left ventricular remodeling after a first myocardial infarction

PURPOSE

Depletion of major blood proteins is one of the most promising approaches to accessing low abundance biomarkers for proteomics studies. The use of combinatorial peptide ligand library (CPLL) for accessing these low abundance proteins in plasma from patients with a myocardial infarction (MI) was tested to identify candidate protein biomarkers of left ventricular remodeling (LVR).

EXPERIMENTAL DESIGN

Serial blood samples of MI patients followed for one year (at inclusion, 1 month, 3 months, and 1 year) were treated with CPLL and analyzed by SELDI-TOF-MS.

RESULT

The use of CPLL increased resolution, with loss of most abundant plasma proteins, reproducibly and improved the intensity of low-abundance proteins. Longitudinal information allowed us to reduce by 55% the final number of peaks identified as significantly modulated throughout the 1-year follow-up after MI. Interestingly, 19 of the 26 peaks finally selected were detected only in samples treated from CPLL. The 2777 m/z peak, found in less elevated level in high remodeling patients, was identified as being DAHKSEVAHR FKDLGEENFKALVL, the N-terminal peptide (24-48 aa) generated from albumin by pepsin cleavage.

CONCLUSIONS AND CLINICAL RELEVANCE

This finding shows the potential of CPLL in accessing low-abundance proteins to select and identify candidate biomarkers in patients with LVR.

Relation of plasma brain natriuretic peptide levels on admission for ST-elevation myocardial infarction to left ventricular end-diastolic volume six months later measured by both echocardiography and cardiac magnetic resonance

The main objective of this study was to investigate the relation between brain natriuretic peptide (BNP) levels within the first 96 hours after ST-segment elevation acute myocardial infarction (STEMI) and the development of left ventricular (LV) dilatation at 6-month follow-up. Eighty-two patients with first STEMIs, reperfused within 12 hours of symptom onset, were prospectively included. Plasma BNP was determined on admission and at 1- and 6-month follow-up. Clinically significant LV dilatation, defined as a >20% increase in LV end-diastolic volume at 6-month follow-up, was assessed using echocardiography and cardiac magnetic resonance. Thirty-two percent of patients developed clinically significant LV dilatation. BNP values on admission and at follow-up were significantly higher in patients who developed clinically significant LV dilatation at 6 months (182 +/- 117 vs 106 +/- 91 pmol/ml). After adjusting for age, infarct size, E-wave deceleration time, and the LV ejection fraction, BNP on admission was an independent predictor of LV dilatation, whether assessed by echocardiography (B = 0.075, p = 0.04) or cardiac magnetic resonance (B = 0.085, p = 0.04). In conclusion, high BNP levels on admission and at follow-up predict LV dilatation after STEMI. The early determination of plasma BNP upon admission for STEMI could be helpful in identifying patients at higher risk for LV dilatation, in whom aggressive management is warranted.

Different patterns of left ventricular enlargement and long-term prognosis after reperfused acute myocardial infarction

BACKGROUND

Dilation of end-systolic and end-diastolic volumes (ESV, EDV) has been used to define left ventricular remodelling after acute myocardial infarction (MI), but the prognostic significance of different enlargement patterns has not been evaluated fully.

AIM

To analyse the evolution of left ventricular volumes and parameters of global and regional contractility and their correlations with long-term prognosis in patients treated by angioplasty in the acute phase of MI.

METHODS

Seventy-four patients (mean age 56+/-13 years; 77% men), treated successfully by angioplasty in the acute phase of MI, were included prospectively. Significant enlargement of left ventricular volumes was defined as a greater than 20% increase between acute phase and 6-month control, assessed by contrast ventriculography. Clinical follow-up was obtained for all patients at 82+/-19 months.

RESULTS

Four groups were identified based on volume evolution: Group I (n=29, 39%; no volume enlargement); Group II (n=8, 11%; isolated EDV enlargement); Group III (n=10, 14%; isolated ESV enlargement); Group IV (n=27, 36%; ESV plus EDV enlargement). Global left ventricular ejection fraction increased in Groups I (p=0.001) and II (p=0.037), but decreased in Groups III (p=0.0002) and IV (p=0.019). The 6-year event-free survival rate was significantly (p=0.0039) better in Groups I and II (100%) than in Groups III and IV (80 and 78%, respectively).

CONCLUSION

ESV enlargement in patients with reperfused acute MI impacts negatively on long-term prognosis, while isolated EDV enlargement does not.

Intracoronary injection of in situ forming alginate hydrogel reverses left ventricular remodeling after myocardial infarction in Swine

OBJECTIVES

This study sought to determine whether alginate biomaterial can be delivered effectively into the infarcted myocardium by intracoronary injection to prevent left ventricular (LV) remodeling early after myocardial infarction (MI).

BACKGROUND

Although injectable biomaterials can improve infarct healing and repair, the feasibility and effectiveness of intracoronary injection have not been studied.

METHODS

We prepared a calcium cross-linked alginate solution that undergoes liquid to gel phase transition after deposition in infarcted myocardium. Anterior MI was induced in swine by transient balloon occlusion of left anterior descending coronary artery. At 4 days after MI, either alginate solution (2 or 4 ml) or saline was injected selectively into the infarct-related coronary artery. An additional group (n = 19) was treated with incremental volumes of biomaterial (1, 2, and 4 ml) or 2 ml saline and underwent serial echocardiography studies.

RESULTS

Examination of hearts harvested after injection showed that the alginate crossed the infarcted leaky vessels and was deposited as hydrogel in the infarcted tissue. At 60 days, control swine experienced an increase in left ventricular (LV) diastolic area by 44%, LV systolic area by 45%, and LV mass by 35%. In contrast, intracoronary injection of alginate (2 and 4 ml) prevented and even reversed LV enlargement (p < 0.01). Post-mortem analysis showed that the biomaterial (2 ml) increased scar thickness by 53% compared with control (2.9 +/- 0.1 mm vs. 1.9 +/- 0.3 mm; p < 0.01) and was replaced by myofibroblasts and collagen.

CONCLUSIONS

Intracoronary injection of alginate biomaterial is feasible, safe, and effective. Our findings suggest a new percutaneous intervention to improve infarct repair and prevent adverse remodeling after reperfused MI.

Left Ventricular Dyssynchrony After Acute Myocardial Infarction is a Powerful Indicator of Left Ventricular Remodeling

Background and Objectives

Left ventricular (LV) remodeling (LVR) after an acute myocardial infarction (AMI) has important clinical implications. We have investigated the prognostic relevance of ventricular systolic dyssnchrony as an indicator of LVR after an AMI.

Subjects and Methods

We enrolled 92 patients (males, 72.8%; mean age, 61.0±13.0 years) with an AMI who underwent successful percutaneous coronary intervention. We analyzed the baseline characteristics, the laboratory and echocardiographic findings, and we performed follow-up echocardiography 6 months after the AMI. The patients were divided into two groups: 1) the presence of LVR, which was defined as an increment of LV end systolic volume (LVESV) >20% compared with the baseline examination; and 2) the absence of LVR.

Results

Twenty-seven patients (29.3%) developed LVR after a 6 month follow-up. There was no statistically significant difference in the clinical and angiographic findings between the two groups. With respect to the laboratory findings, the LVR group had a higher peak creatine kinase MB (CK-MB) (149.9±155.0 vs. 74.6±69.7 U/L, p=0.001) and troponin-I (70.2±73.3 vs. 43.2±39.5 ng/mL, p=0.024) level than the group without LVR. With respect to echocardiographic findings, the baseline LV ejection fraction (EF) and LVESV were not significantly different (LVESV, 73.0±37.3 vs. 91.3±52.0 mL, p=0.013; and EF, 58.3±13.3 vs. 55.6±11.8%, p=0.329) between the groups with and without LVR, respectively. The degree of LV dyssynchrony, which was assessed by tissue Doppler imaging, was significantly higher in the LVR group than the group without LVR (75.2±43.4 vs. 38.3±32.5 ms), and the degree of LV dyssynchrony was an independent predictor for LVR based on multivariate analysis {hazard ratio (HR)=0.097, p<0.001}. In receiver operating characteristics (ROC) curve analysis, the area under the curve (AUC) was 0.754 and a cutoff value of 45.9 predicted the development of LVR with 74.1% sensitivity and 72.3% specificity.

Conclusion

The presence of LV dyssynchroncy immediately after a myocardial infarction is an important predictive factor for development LVR.

Proteomic analysis of left ventricular remodeling in an experimental model of heart failure

The development of chronic heart failure (CHF) following myocardial infarction is characterized by progressive alterations of left ventricle (LV) structure and function called left ventricular remodeling (LVR), but the mechanism of LVR remains still unclear. Moreover, information concerning the global alteration protein pattern during the LVR will be helpful for a better understanding of the process. We performed differential proteomic analysis of whole LV proteins using an experimental model of CHF in which myocardial infarction was induced in adult male rats by left coronary ligation. Among 1000 protein spots detected in 2D-gels, 49 were differentially expressed in LV of 2-month-old CHF-rats, corresponding to 27 different identified proteins (8 spots remained unidentified), classified in different functional groups as being heat shock proteins, reticulum endoplasmic stress proteins, oxidative stress proteins, glycolytic enzymes, fatty acid metabolism enzymes, tricarboxylic acid cycle proteins and respiratory chain proteins. We validated modulation of selected proteins using Western blot analysis. Our data showed that proteins involved in cardiac metabolism and oxidative stress are modulated during LVR. Interestingly, proteins of stress response showed different adaptation pathways in the early and late phase of LVR. Expression of four proteins, glyceraldehyde-3-phosphate dehydrogenase, alphaB-crystallin, peroxiredoxin 2, and isocitrate dehydrogenase, was linked to echographic parameters according to heart failure severity.

Maximum persisting single lead ST elevation after primary angioplasty: a good predictor of left ventricular dilatation assessed by magnetic resonance imaging

AIMS

To determine the frequency and predictors of left ventricular dilatation assessed by magnetic resonance imaging among patients with a first acute myocardial infarction treated with successful primary angioplasty and stent.

METHODS AND RESULTS

Cine magnetic resonance imaging and late enhancement imaging were prospectively performed in 42 patients 1 month and more than 1 year after successful early reperfusion of a first acute ST elevation myocardial infarction (age 61 +/- 13 years, 76% men, 55% anterior myocardial infarction, and mean symptom-to-balloon time 199 +/- 130 min). Both at the 1-month and at the 15-month magnetic resonance imaging examinations, 57% of patients had left ventricular dilatation (end-systolic volume indexed > 36 ml/m2, values above the upper 95th percentile based on magnetic resonance imaging reference values for left ventricular size in normal participants). The most accurate predictor of left ventricular dilatation was maximum persisting single lead ST elevation 60 min after reperfusion (area under the curve 0.81, P = 0.001). Maximum single lead ST elevation was significantly and independently associated with larger end-systolic volume indexed (beta = 0.35, P = 0.040) after adjusting for muscle and brain isoenzyme of creatine kinase and echocardiographic wall motion score index.

CONCLUSION

More than half of patients with a first acute myocardial infarction have left ventricular dilatation despite successful primary coronary angioplasty. Maximum persisting single lead ST elevation 60 min after mechanical reperfusion represents a simple tool for predicting left ventricular dilatation.

Predicting left ventricular remodeling after a first myocardial infarction by plasma proteome analysis

Recent improvements in therapeutic strategies did not prevent left ventricular remodeling (LVR), which remains a common event (30%) after acute myocardial infarction (AMI). We report the use of a systematic approach, based on comparative proteomics, to select circulating biomarkers that may be associated with LVR. We selected 93 patients enrolled in a prospective study. These patients with anterior wall Q-wave AMI underwent echocardiographic follow-up at hospitalization, 3 months and 1 year after AMI. They were divided into three groups (no, low, or high remodeling). Plasma samples of these patients (day 5 of hospitalization) were processed and stored at -80 degrees C within 2 h and analyzed using SELDI-TOF protein chip technology. This systematic approach allowed to select candidate proteins modulated by LVR: post-translational variants of alpha1-chain of haptoglobin (Hpalpha1) corresponding to m/z 9493, 9565, and 9623, which were more elevated in remodeling patients. The peak 9493 m/z was shown having a receiving-operating characteristic (ROC) value of 0.71 between non- and remodeling patients. SELDI-TOF approach may lead to the identification of circulating proteins associated with LVR. Whether these candidate proteins will help to identify patients who are at high risk of heart failure after AMI will have to be tested in future studies.

Left ventricular remodeling is associated with the severity of mitral regurgitation after inaugural anterior myocardial infarction--optimal timing for echocardiographic imaging

BACKGROUND

Although mitral regurgitation (MR) has been associated with an increased risk of death and heart failure after myocardial infarction (MI), the relationship between post-MI MR and left ventricular (LV) remodeling has not been entirely clarified. In addition, the optimal timing for assessing MR after MI remains unknown.

METHODS

Post-MI MR was assessed by Doppler echocardiography at hospital discharge (baseline) and after 3 months in 261 patients with an inaugural anterior MI. We studied LV remodeling during a 1-year period and clinical follow-up after 3 years, according to MR severity at baseline and at 3 months.

RESULTS

Left ventricular remodeling was demonstrated as an increase in LV end-diastolic volume from 56 +/- 15 mL/m(2) at baseline to 63 +/- 19 mL/m(2) at 1 year (P < .0001). MR severity at baseline was not significantly associated with LV remodeling. By contrast, MR severity at 3 months was a strong indicator of LV remodeling. There was a graded increase in the proportion of patients with a >20% increase in LV end-diastolic volume between baseline and 1 year according to MR severity at 3 months (no MR: 21%, mild MR: 32%, moderate/severe MR: 60%) (P = .008). Both MR at baseline and at 3 months were associated with death or rehospitalization for heart failure by univariate analysis (P = .014 and P < .0001, respectively). By multivariable analysis, MR at baseline was not an independent predictor of adverse outcome (P = .66). By contrast, MR at 3 months was independently associated with adverse outcome with a hazard ratio of 2.23 (1.02-4.91 [P = .04]).

CONCLUSIONS

After an inaugural anterior MI, MR is associated with LV remodeling and adverse clinical outcome. For prognostic purpose, the optimal timing for assessing MR is the chronic post-MI stage rather than the early post-MI period.

Inhibiting the renin-angiotensin system with ACE Inhibitors or ARBs after MI

As part of the recommended modern post-myocardial infarction (MI) management, including reperfusion strategies, antiplatelet therapy, and beta-blockers, we may wonder whether the impact of early inhibition of the renin-angiotensin system (RAS) is as important as it was 20 years ago. This review demonstrates that significant clinical benefit can be derived from angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) even when added to other currently recommended treatment strategies in post-MI patients. Moreover, the effects of RAS inhibition extend far beyond the early post-MI neurohormonal activation and left ventricular remodeling phases. The favorable effects of RAS inhibition on important prognostic markers such as atrial fibrillation, renal function, and diabetes have recently been unraveled. Post-MI RAS inhibition also benefits all age groups, including elderly patients.

Relation of admission white blood cell count to left ventricular remodeling after anterior wall acute myocardial infarction

We investigated whether a high white blood cell (WBC) count on admission for acute myocardial infarction (AMI) may be associated with a higher risk of subsequent left ventricular (LV) remodeling. We included 107 patients with anterior AMI. Echocardiographic studies were performed at hospital discharge, at 3 months, and at 1 year after AMI. LV remodeling (>20% increase in end-diastolic volume) was observed in 27% of patients. WBC counts during hospitalization were higher in patients who subsequently underwent LV remodeling (p = 0.003 for WBC count on admission). The increase in end-diastolic volume from baseline to 1 year was greater for patients in the higher tertile of WBC count on admission (p = 0.04). When adjusting for baseline clinical and echocardiographic characteristics by multivariate analysis, WBC count on admission was independently associated with LV remodeling (odds ratio 1.23, 95% confidence interval 1.04 to 1.45, p = 0.018). In conclusion, a high WBC count on admission for AMI is an independent predictor of LV remodeling, even when predischarge echocardiographic variables are taken into account.

A prospective evaluation of left ventricular remodeling after inaugural anterior myocardial infarction as a function of gene polymorphisms in the renin-angiotensin-aldosterone, adrenergic, and metalloproteinase systems

BACKGROUND

Left ventricular remodeling (LVR) is a strong predictor of cardiovascular events after myocardial infarction (MI). Although several factors have been shown to influence LVR, interindividual variability exists. Some studies have suggested that gene polymorphisms may be associated with LVR, but these studies were limited by either a retrospective design or the inclusion of limited patient numbers. The present study was designed to prospectively assess the impact of gene polymorphisms on LVR.

METHODS

We included 266 patients with inaugural anterior MI. Systematic echocardiographic follow-ups were performed at 3 months and at 1 year after MI. The polymorphisms were selected using a candidate gene approach based on LVR pathophysiology. We analyzed 14 polymorphisms in 3 different systems: the renin-angiotensin-aldosterone system (ACE I/D, RAT1 1166A/C, angiotensinogen M235T, CYP11B2 -344C/T), the adrenergic system (beta1AR Ser49Gly, beta1AR Gly389Arg, beta2AR Gly16Arg, beta2AR Gln27Glu, beta2AR Thr164Ile, alpha2cAR Del322-325), and the metalloproteinase (MMP) system (-1607 1G/2G MMP-1, -1306 C/T MMP-2, -1171 5A/6A MMP-3, -1562 C/T MMP-9).

RESULTS

Left ventricular remodeling was documented by a progressive increase in end-diastolic volume from 56.5 +/- 14.9 mL/m2 at baseline to 62.8 +/- 18.8 mL/m2 at 1 year (P < .0001). End-diastolic volume at baseline, 3 months, or 1 year did not differ significantly among genotypes for any polymorphism. The change in end-diastolic volume from baseline to 1 year was also similar among genotypes for all polymorphisms.

CONCLUSIONS

Left ventricular remodeling after MI is not associated with common polymorphisms in the renin-angiotensin-aldosterone, adrenergic, or MMP systems.

Relationship Between Peripheral Monocytosis and Nonrecovery of Left Ventricular Function in Patients With Left Ventricular Dysfunction Complicated With Acute Myocardial Infarction

BACKGROUND

Although ischemic heart failure is a major cause of mortality after acute myocardial infarction (AMI), the factors that may influence the nonrecovery of left ventricular function (LVF) after an AMI are still unclear. The aim of this study was to identify predictors of nonrecovery of LVF in patients with left ventricular (LV) dysfunction (defined as an echocardiographic ejection fraction (EF)<40%) complicated with AMI who undergo successful primary percutaneous coronary intervention (PCI).

METHODS AND RESULTS

LVF recovery was defined as improvement of LVEF more than 10% compared with baseline LVEF at follow-up. One hundred and eight patients with LV dysfunction after AMI were divided into 2 groups according to the LVF recovery at follow-up: patients with LVF recovery (n=64) vs patients without LVF recovery (n=44). The follow-up LVEF was measured at 8+/-4 months after PCI. Patients without LVF recovery were older (76+/-13 years vs 59+/-14 years, p=0.023) and the baseline peak monocyte count, creatine kinase, and troponin I levels were significantly higher in patients without LVF recovery than in patients with LVF recovery. Delta LVEF (follow-up LVEF-baseline LVEF) correlated with baseline peak monocyte count (r=-0.417, p<0.001), baseline peak creatine kinase (r=-0.269, p=0.005), and baseline peak troponin I levels (r=-0.256, p=0.007). Multivariate analyses showed that baseline peak monocyte count and old age were the independent predictors of nonrecovery of LVF (hazard ratio; 3.38, 95% confidence interval (CI): 1.16-5.43, p=0.012, and hazard ratio; 2.38, 95% CI: 1.09-4.87, p=0.025, respectively).

CONCLUSION

Peripheral monocytosis is associated with nonrecovery of LVF in patients with LV dysfunction complicating an AMI who underwent successful primary PCI. These results suggest an important role of monocytes in the expansion of the infarct and the development of chronic ischemic heart failure after reperfusion therapy.