Redefining Adverse and Reverse Left Ventricular Remodeling by Cardiovascular Magnetic Resonance Following ST-Segment-Elevation Myocardial Infarction and Their Implications on Long-Term Prognosis

Empagliflozin to prevent progressive adverse remodelling after myocardial infarction (EMPRESS-MI): rationale and design

AIMS

Patients with a reduced left ventricular ejection fraction (LVEF) following an acute myocardial infarction (MI) are at risk of progressive adverse cardiac remodelling that can lead to the development of heart failure and death. The early addition of a sodium-glucose cotransporter 2 (SGLT2) inhibitor to standard treatment may delay or prevent progressive adverse remodelling in these patients.

METHODS AND RESULTS

EMpagliflozin to PREvent worSening of left ventricular volumes and Systolic function after Myocardial Infarction (EMPRESS-MI) is a randomized, double-blind, placebo-controlled, multi-centre trial designed to assess the effect of empagliflozin on cardiac remodelling evaluated using cardiovascular magnetic resonance (CMR) in 100 patients with left ventricular systolic dysfunction following MI. Eligible patients were those ≥12 h and ≤14 days following acute MI, with an LVEF <45% by CMR. Patients were randomized to empagliflozin 10 mg once a day or matching placebo. The primary outcome will be change in left ventricular end-systolic volume indexed to body surface area over 24 weeks from randomization. Secondary endpoints include measures of left ventricular and atrial volumes, left ventricular mass, LVEF, and circulating cardiac biomarkers.

CONCLUSIONS

EMPRESS-MI will assess the effect of the SGLT2 inhibitor empagliflozin on cardiac remodelling in patients with left ventricular systolic dysfunction after an acute MI.

Left Atrial Strain for Prediction of Left Ventricular Reverse Remodeling After ST-segment Elevation Myocardial Infarction by Cardiac Magnetic Resonance Feature Tracking

PURPOSE

The study aimed to investigate the potential utility of left atrial (LA) strain by using cardiac magnetic resonance feature-tracking (CMR-FT) to predict left ventricular reverse remodeling (LVRR) following ST-segment elevation myocardial infarction (STEMI).

MATERIALS AND METHODS

Patients with a first STEMI treated by primary percutaneous coronary intervention were consecutively enrolled in the prospective study and underwent CMR scans at 5 days and 4 months. LA global longitudinal strain (reservoir strain [εs], conduit strain [εe], booster strain [εa]) and corresponding strain rate were assessed by CMR-FT using cine images. LVRR was defined as a reduction in the LV end-systolic volume index of >10% from baseline to follow-up. Logistic regression analyses were performed to determine the predictors of LVRR.

RESULTS

Of 90 patients analyzed, patients with LVRR (n=35, 39%) showed higher values of LA strain and strain rate and less extensive infarct size (IS) compared with patients without LVRR (n=55, 61%) at initial and second CMR. The LVRR group demonstrated significant improvements in LV and LA cardiac function over time, especially the obvious increase in LA strain and strain rate. In multivariate logistic regression analyses, εs and εe, together with IS, were independent predictors of LVRR. The combination of εs and IS could optimally predict the LVRR with the highest area under the curve of 0.743.

CONCLUSIONS

Post-STEMI patients with LVRR presented better recovery from cardiac function and LA deformation compared with patients without LVRR. Assessment of εs and εe by using CMR-FT after STEMI enabled prediction of LVRR.

Cardiac Magnetic Resonance Evaluation of LV Remodeling Post-Myocardial Infarction: Prognosis, Monitoring and Trial Endpoints

Adverse left ventricular remodeling (ALVR) and subsequent heart failure after myocardial infarction (MI) remain a major cause of patient morbidity and mortality worldwide. Overt inflammation has been identified as the common pathway underlying myocardial fibrosis and development of ALVR post-MI. With its ability to simultaneously provide information about cardiac structure, function, perfusion, and tissue characteristics, cardiac magnetic resonance (CMR) is well poised to inform prognosis and guide early surveillance and therapeutics in high-risk cohorts. Further, established and evolving CMR-derived biomarkers may serve as clinical endpoints in prospective trials evaluating the efficacy of novel anti-inflammatory and antifibrotic therapies. This review provides an overview of post-MI ALVR and illustrates how CMR may help clinical adoption of novel therapies via mechanistic or prognostic imaging markers.

Myocardial DNA Damage Predicts Heart Failure Outcome in Various Underlying Diseases

BACKGROUND

Reliable predictors of treatment efficacy in heart failure have been long awaited. DNA damage has been implicated as a cause of heart failure.

OBJECTIVES

The purpose of this study was to investigate the association of DNA damage in myocardial tissue with treatment response and prognosis of heart failure.

METHODS

The authors performed immunostaining of DNA damage markers poly(ADP-ribose) (PAR) and γ-H2A.X in endomyocardial biopsy specimens from 175 patients with heart failure with reduced ejection fraction (HFrEF) of various underlying etiologies. They calculated the percentage of nuclei positive for each DNA damage marker (%PAR and %γ-H2A.X). The primary outcome was left ventricular reverse remodeling (LVRR) at 1 year, and the secondary outcome was a composite of cardiovascular death, heart transplantation, and ventricular assist device implantation.

RESULTS

Patients who did not achieve LVRR after the optimization of medical therapies presented with significantly higher %PAR and %γ-H2A.X. The ROC analysis demonstrated good performance of both %PAR and %γ-H2A.X for predicting LVRR (AUCs: 0.867 and 0.855, respectively). There was a negative correlation between the mean proportion of DNA damage marker-positive nuclei and the probability of LVRR across different underlying diseases. In addition, patients with higher %PAR or %γ-H2A.X had more long-term clinical events (PAR HR: 1.63 [95% CI: 1.31-2.01]; P < 0.001; γ-H2A.X HR: 1.48 [95% CI: 1.27-1.72]; P < 0.001).

CONCLUSIONS

DNA damage determines the consequences of human heart failure. Assessment of DNA damage is useful to predict treatment efficacy and prognosis of heart failure patients with various underlying etiologies.

Patterns of left ventricular remodeling post-myocardial infarction, determinants, and outcome

AIM

Left ventricular remodeling (LVR) after myocardial infarction (MI) can lead to heart failure, arrhythmia, and death. We aim to describe adverse LVR patterns at 6 months post-MI and their relationships with subsequent outcomes and to determine baseline.

METHODS AND RESULTS

A multicenter cohort of 410 patients (median age 57 years, 87% male) with reperfused MI and at least 3 akinetic LV segments on admission was analyzed. All patients had transthoracic echocardiography performed 4 days and 6 months post-MI, and 214 also had cardiac magnetic resonance imaging performed on day 4. To predict LVR, machine learning methods were employed in order to handle many variables, some of which may have complex interactions. Six months post-MI, echocardiographic increases in LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), and LV ejection fraction (LVEF) were 14.1% [interquartile range 0.0, 32.0], 5.0% [- 14.0, 25.8], and 8.7% [0.0, 19.4], respectively. At 6 months, ≥ 15% or 20% increases in LVEDV were observed in 49% and 42% of patients, respectively, and 37% had an LVEF < 50%. The rate of death or new-onset HF at the end of 5-year follow-up was 8.8%. Baseline variables associated with adverse LVR were determined best by random forest analysis and included stroke volume, stroke work, necrosis size, LVEDV, LVEF, and LV afterload, the latter assessed by Ea or Ea/Ees. In contrast, baseline clinical and biological characteristics were poorly predictive of LVR. After adjustment for predictive baseline variables, LV dilation > 20% and 6-month LVEF < 50% were significantly associated with the risk of death and/or heart failure: hazard ratio (HR) 2.12 (95% confidence interval (CI) 1.05-4.43; p = 0.04) and HR 2.68 (95% CI 1.20-6.00; p = 0.016) respectively.

CONCLUSION

Despite early reperfusion and cardioprotective therapy, adverse LVR remains frequent after acute MI and is associated with a risk of death and HF. A machine learning approach identified and prioritized early variables that are associated with adverse LVR and which were mainly hemodynamic, combining LV volumes, estimates of systolic function, and afterload.

Colchicine in acute myocardial infarction: cardiovascular events at 1-year follow up

OBJECTIVE

In the COVERT-MI randomised placebo-controlled trial, oral administration of high-dose colchicine at the time of reperfusion and for 5 days in acute ST-elevated myocardial infarction did not reduce infarct size but was associated with a significant increase in left ventricular thrombus (LVT) in comparison to placebo. We aimed to assess the 1-year clinical outcomes of the study population.

METHODS

This study is a follow-up analysis of the COVERT-MI study on prespecified secondary clinical endpoints at 1 year. The primary endpoint of this study was a composite of major adverse cardiovascular events (MACEs), including all-cause death, acute coronary syndromes, heart failure events, ischaemic strokes, sustained ventricular arrhythmias and acute kidney injury at 1-year follow-up. The quality of life (QOL) and the drug therapy prescription were also assessed.

RESULTS

At 1 year, 192 patients (101 patients in the colchicine group, 91 in the placebo group) were followed up. Seventy-six (39.6%) MACEs were reported in the study population. There was no significant difference regarding the number of MACEs between groups: 36 (35.6%) in the colchicine group and 40 (44.1%) in the placebo group (p=0.3). There were no differences in the occurrence of ischaemic strokes between the colchicine group and the control group (3 (3%) vs 2 (2.2%), respectively, p=0.99). There was a trend towards fewer heart failure events in the colchicine group compared with the placebo group (12 (11.9%) vs 18 (19.8%), p=0.20). There was no significant difference in QOL scores at 1 year (75.8±15.7 vs 72.7±16.2 respectively, p=0.18).

CONCLUSIONS

There was no significant difference between the colchicine and placebo groups at 1 year regarding MACEs, especially concerning deaths or ischaemic strokes. No excess of ischaemic adverse events was observed despite the initial increase in LVT in the colchicine group.

TRIAL REGISTRATION NUMBER

NCT0315681.

Cardiovascular magnetic resonance imaging-derived intraventricular pressure gradients in ST-segment elevation myocardial infarction: a long-term follow-up study

Aims

Recently, novel post-processing tools have become available that measure intraventricular pressure gradients (IVPGs) on routinely obtained long-axis cine cardiac magnetic resonance (CMR) images. IVPGs provide a comprehensive overview of both systolic and diastolic left ventricular (LV) functions. Whether IVPGs are associated with clinical outcome after ST-elevation myocardial infarction (STEMI) is currently unknown. Here, we investigated the association between CMR-derived LV-IVPGs and major adverse cardiovascular events (MACE) in a large reperfused STEMI cohort with long-term outcome.

Methods and results

In this prospectively enrolled multi-centre cohort study, 307 patients underwent CMR within 14 days after the first STEMI. LV-IVPGs (from apex-to-base) were estimated on the long-axis cine images. During a median follow-up of 9.7 (5.9-12.5) years, MACE (i.e. composite of cardiovascular death and de novo heart failure hospitalisation) occurred in 49 patients (16.0%). These patients had larger infarcts, more often microvascular injury, and impaired LV-IVPGs. In univariable Cox regression, overall LV-IVPG was significantly associated with MACE and remained significantly associated after adjustment for common clinical risk factors (hazard ratio (HR) 0.873, 95% confidence interval (CI) 0.794-0.961, P = 0.005) and myocardial injury parameters (HR 0.906, 95% CI 0.825-0.995, P = 0.038). However, adjusted for LV ejection fraction and LV global longitudinal strain (GLS), overall LV-IVPG does not provide additional prognostic information (HR 0.959, 95% CI 0.866-1.063, P = 0.426).

Conclusion

Early after STEMI, CMR-derived LV-IVPGs are univariably associated with MACE and this association remains significant after adjustment for common clinical risk factors and measures of infarct severity. However, LV-IVPGs do not add prognostic value to LV ejection fraction and LV GLS.

The optimal definition and prediction nomogram for left ventricular remodelling after acute myocardial infarction

AIMS

Left ventricular (LV) remodelling after acute myocardial infarction (AMI) is associated with heart failure and increased mortality. There was no consensus on the definition of LV remodelling, and the prognostic value of LV remodelling with different definitions has not been compared. We aimed to find the optimal definition and develop a prediction nomogram as well as online calculator that can identify patients at risk of LV remodelling.

METHODS AND RESULTS

This prospective, observational study included 829 AMI patients undergoing percutaneous coronary intervention from January 2015 to January 2020. Echocardiography was performed within the 48 h of admission and at 6 months after infarction to evaluate LV remodelling, defined as a 20% increase in LV end-diastolic volume (LVEDV), a 15% increase in LV end-systolic volume (LVESV), or LV ejection fraction (LVEF) < 50% at 6 months. The impact of LV remodelling on long-term outcomes was analysed. Lasso regression was performed to screen potential predictors, and multivariable logistic regression analysis was conducted to establish the prediction nomogram. The area under the curve, calibration curve and decision curve analyses were used to determine the discrimination, calibration and clinical usefulness of the remodelling nomogram. The incidences of LV remodelling defined by LVEDV, LVESV and LVEF were 24.85% (n = 206), 28.71% (n = 238) and 14.60% (n = 121), respectively. Multivariable Cox regression models demonstrated that different definitions of LV remodelling were independently associated with the composite endpoint. However, only remodelling defined by LVEF was significantly connected with long-term mortality (hazard ratio = 2.78, 95% confidence interval 1.41-5.48, P = 0.003). Seven variables were selected to construct the remodelling nomogram, including diastolic blood pressure, heart rate, AMI type, stent length, N-terminal pro brain natriuretic peptide, troponin I, and glucose. The prediction model had an area under the receiver operating characteristics curve of 0.766. The calibration curve and decision curve analysis indicated consistency and better net benefit in the prediction model.

CONCLUSIONS

LV remodelling defined by LVEDV, LVESV and LVEF were independent predictors for long-term mortality or heart failure hospitalization in AMI patients after percutaneous coronary intervention. However, only remodelling defined by LVEF was suitable for predicting all-cause death. In addition, the nomogram can provide an accurate and effective tool for the prediction of postinfarct remodelling.

Delays in first medical contact to primary interventional therapy and left ventricular remodelling in ST-segment elevation myocardial infarction

BACKGROUND

Early reperfusion and early evaluation of adverse cardiovascular events have become important aspects of treatment for ST-segment elevation myocardial infarction post-primary percutaneous coronary intervention (PPCI). However, emergency medical service (EMS) delays always occur, especially in developing countries.

AIMS

The aim of this study was to investigate the impact of EMS delays on short-term predictions of the severity of myocardial injury in STEMI patients after PPCI.

METHODS

A total of 151 STEMI patients who underwent successful PPCI and two postoperative cardiac magnetic resonance (CMR) imaging examinations (1 week and 4 months postoperatively) were retrospectively analysed. CMR cine and late gadolinium enhancement (LGE) images were analysed to evaluate left ventricular (LV) function, LV global longitudinal peak strain (GLS) and scar characteristics. The time from first medical contact to balloon (FMC2B) and door-to-balloon (D2B) time, expressed in minutes, were recorded and compared with the recommended timelines. Unadjusted and multivariable analyses were used to assess the impact of EMS delays on short-term left ventricular remodelling (ALVR).

RESULTS

EMS delays (FMC2B time > 90 min) led to larger infarct size (IS) and microcirculation obstruction (MVO) and poor recovery of the LV ejection fraction and GLS (all p < 0.05). Logistic regression analysis showed that an FMC2B time > 90 min (p = 0.028, OR = 2.661, 95% CI 1.112-6.367) and baseline IS (p = 0.016, OR = 1.079, 95% CI 1.015-1.148) were independent predictors of short-term ALVR.

CONCLUSION

Delays in FMC2B time were strongly associated with short-term ALVR; shorter ischaemic times may improve the cardiac function and prognosis of patients.

Cardioprotective Effect of Empagliflozin and Circulating Ketone Bodies During Acute Myocardial Infarction

BACKGROUND

SGLT2i (sodium-glucose cotransporter-2 inhibitors) improve clinical outcomes in patients with heart failure, but the mechanisms of action are not completely understood. SGLT2i increases circulating levels of ketone bodies, which has been demonstrated to enhance myocardial energetics and induce reverse ventricular remodeling. However, the role of SGLT2i or ketone bodies on myocardial ischemia reperfusion injury remains in the dark. The objective of this study is to investigate the cardioprotective potential of empagliflozin and ketone bodies during acute myocardial infarction (MI).

METHODS

We used a nondiabetic porcine model of ischemia reperfusion using a percutaneous occlusion of proximal left anterior descending artery for 45 minutes. Animals received 1-week pretreatment with either empagliflozin or placebo prior to MI induction. Additionally, a third group received intravenous infusion of the ketone body BOHB (beta-hydroxybutyrate) during the MI induction. Acute effects of the treatments were assessed 4-hour post-MI by cardiac magnetic resonance and histology (thioflavin for area at risk, triphenyltetrazolium chloride staining for MI size). All animals were euthanized immediately postcardiac magnetic resonance, and heart samples were collected.

RESULTS

The area at risk was similar in all groups. Empagliflozin treatment increased BOHB levels. Empagliflozin-treated animals showed significantly higher myocardial salvage, smaller MI size (both by cardiac magnetic resonance and histology), less microvascular obstruction, and improved cardiac function (left ventricle ejection fraction and strain). Furthermore, empagliflozin-treated animals demonstrated reduced biomarkers of cardiomyocyte apoptosis and oxidative stress compared with placebo. The BOHB group showed similar results to the empagliflozin group.

CONCLUSIONS

One-week pretreatment with empagliflozin ameliorates ischemia reperfusion injury, reduces MI size and microvascular obstruction, increases myocardial salvage, preserves left ventricle systolic function, and lowers apoptosis and oxidative stress. Periprocedural intravenous infusion of BOHB during myocardial ischemia also induces cardioprotection, suggesting a role for BOHB availability as an additional mechanism within the wide spectrum of actions of SGLT2i.

Machine learning-based prediction of infarct size in patients with ST-segment elevation myocardial infarction: A multi-center study

BACKGROUND

Cardiac magnetic resonance imaging (CMR) is the gold standard for measuring infarct size (IS). However, this method is expensive and requires a specially trained technologist to administer. We therefore sought to quantify the IS using machine learning (ML) based analysis on clinical features, which is a convenient and cost-effective alternative to CMR.

METHODS AND RESULTS

We included 315 STEMI patients with CMR examined one week after morbidity in final analysis. After feature selection by XGBoost on fifty-six clinical features, we used five ML algorithms (random forest (RF), light gradient boosting decision machine, deep forest, deep neural network, and stacking) to predict IS with 26 (selected by XGBoost with information gain greater than average level of 56 features) and the top 10 features, during which 5-fold cross-validation were used to train and optimize models. We then evaluated the value of actual and ML-IS for the prediction of adverse remodeling. Our finding indicates that MLs outperform the linear regression in predicting IS. Specifically, the RF with five predictors identified by the exhaustive method performed better than linear regression (LR) with 10 indicators (R² of RF: 0.8; LR: 0). The finding also shows that both actual and ML-IS were independently associated with adverse remodeling. ML-IS ≥ 21% was associated with a twofold increase in the risk of LV remodeling (P < 0.01) compared with patients with reference IS (1st tertile).

CONCLUSION

ML-based methods can predict IS with widely available clinical features, which provide a proof-of-concept tool to quantitatively assess acute phase IS.

Left Ventricular Adverse Remodeling in Ischemic Heart Disease: Emerging Cardiac Magnetic Resonance Imaging Biomarkers

Post-ischemic left ventricular (LV) remodeling is a biologically complex process involving myocardial structure, LV shape, and function, beginning early after myocardial infarction (MI) and lasting until 1 year. Adverse remodeling is a post-MI maladaptive process that has been associated with long-term poor clinical outcomes. Cardiac Magnetic Resonance (CMR) is the best tool to define adverse remodeling because of its ability to accurately measure LV end-diastolic and end-systolic volumes and their variation over time and to characterize the underlying myocardial changes. Therefore, CMR is the gold standard method to assess in vivo myocardial infarction extension and to detect the presence of microvascular obstruction and intramyocardial hemorrhage, both associated with adverse remodeling. In recent times, new CMR quantitative biomarkers emerged as predictive of post-ischemic adverse remodeling, such as T1 mapping, myocardial strain, and 4D flow. Additionally, CMR T1 mapping imaging may depict infarcted tissue and assess diffuse myocardial fibrosis by using surrogate markers such as extracellular volume fraction, which may predict functional recovery or risk stratification of remodeling. Finally, there is emerging evidence supporting the utility of intracavitary blood flow kinetic energy and hemodynamic features assessed by the 4D flow CMR technique as early predictors of remodeling.

Three-dimensional echocardiographic assessment of left ventricular geometric changes following acute myocardial infarction

Acute ST-segment elevation myocardial infarction (STEMI) is associated with left ventricular (LV) structural and functional consequences. We aimed to elucidate LV geometric changes following STEMI using three-dimensional (3D) echocardiography (3DE) and to assess their functional implications using two-dimensional (2D) speckle tracking echocardiography (STE). The study included 71 patients with STEMI who underwent baseline and 6-month follow-up 2D- and 3DE. Measured parameters included LV dimensions, biplane volumes, wall motion assessment, 2D LV global longitudinal strain (GLS), and 3D LV volumes, sphericity index and systolic dyssynchrony index. According to 3DE, LV geometric changes were classified as, adverse remodeling, reverse remodeling, and minimal LV volumetric changes. The occurrence of in-hospital and follow-up major adverse cardiovascular events (MACE) was assessed among the study population. The incidence of developing adverse remodeling was 25.4% while that of reverse remodeling was 36.6%. Adverse remodeling patients had significantly higher in-hospital MACE. Reverse remodeling was associated with significantly improved GLS, that was less evident in those with minimal LV geometric changes, and non-significant improvement for adverse remodeling group. LV baseline 2D GLS significantly correlated with follow-up 3D volumes among both reverse and adverse remodeling groups. Female gender and higher absolute GLS change upon follow-up were significantly associated with reverse remodeling. ROC-derived cutoff for adverse remodeling reallocated a substantial number of patients from the minimal change group to the adverse remodeling. Following acute STEMI, two-dimensional GLS was associated with and potentially predictive of changes in LV volumes as detected by three-dimensional echocardiography.

Impact of Obstructive Sleep Apnea Syndrome on Ventricular Remodeling after Acute Myocardial Infarction: A Proof-of-Concept Study

Background: Obstructive sleep apnea syndrome (OSA) is common in patients with acute myocardial infarction (AMI). Whether OSA impacts on the ventricular remodeling post-AMI remains unclear. We compared cardiac ventricular remodeling in patients assessed by cardiac magnetic resonance (CMR) imaging at baseline and six months after AMI based on the presence and severity of OSA. Methods: This prospective study included 47 patients with moderate to severe AMI. They all underwent CMR at inclusion and at six months after an AMI, and a polysomnography was performed three weeks after AMI. Left and right ventricular remodeling parameters were compared between patients based on the AHI, AHI in REM and NREM sleep, oxygen desaturation index, and daytime sleepiness. Results: Of the 47 patients, 49% had moderate or severe OSA with an AHI ≥ 15/h. No differences were observed between these patients and those with an AHI < 15/h for left ventricular end-diastolic and end-systolic volumes at six months. No association was found for left and right ventricular remodeling parameters at six months or for the difference between baseline and six months with polysomnographic parameters of OSA severity, nor with daytime sleepiness. Conclusions: Although with a limited sample size, our proof-of-concept study does not report an association between OSA and ventricular remodeling in patients with AMI. These results highlight the complexity of the relationships between OSA and post-AMI morbi-mortality.

Ischemic Cardiomyopathy and Heart Failure After Acute Myocardial Infarction

Purpose of Review

Ischemic cardiomyopathy refers to systolic left ventricular dysfunction in the setting of obstructive coronary artery disease and represents the most common cause of heart failure worldwide. It is often the combination of an irreversible loss of viable mass following an acute myocardial infarction (AMI) with a dysfunctional, but still viable, myocardium in the context of a chronically reduced myocardial blood flow and reduced coronary reserve. Medical treatments aiming at modulating neurohumoral response and restoring blood flow to the ischemic cardiomyocytes were shown to dramatically abate the occurrence of ventricular dysfunction and adverse remodeling in ischemic cardiomyopathy.

Recent Findings

Novel therapeutic approaches, such as mechanical unloading and modulation of the inflammatory response, appear to be promising. Furthermore, the understanding of the mechanisms by which, despite optimal treatment, heart failure ensues after AMI, with or without adverse remodeling and systolic dysfunction, is a critical step in the search for novel ways to tackle heart failure risk beyond preservation of left ventricular volumes and systolic function.

Summary

In this review article, we explore the principal pathophysiological mechanisms and pathways of heart failure in ischemic cardiomyopathy, therapeutic opportunities, and knowledge gaps in this area.

Cardiovascular magnetic resonance characteristics and clinical outcomes of patients with ST-elevation myocardial infarction and no standard modifiable risk factors–A DANAMI-3 substudy

Introduction

A higher 30-day mortality has been observed in patients with first-presentation ST elevation myocardial infarction (STEMI) who have no standard modifiable cardiovascular risk factors (SMuRFs), i. e., diabetes, hypertension, hyperlipidemia, and current smoker. In this study, we evaluate the clinical outcomes and CMR imaging characteristics of patients with and without SMuRFs who presented with first-presentation STEMI.

Methods

Patients from the Third DANish Study of Acute Treatment of Patients With ST-Segment Elevation Myocardial Infarction (DANAMI-3) with first-presentation STEMI were classified into those with no SMuRFs vs. those with at least one SMuRF.

Results

We identified 2,046 patients; 283 (14%) SMuRFless and 1,763 (86%) had &gt;0 SMuRF. SMuRFless patients were older (66 vs. 61 years, p &lt; 0.001) with more males (84 vs. 74%, p &lt; 0.001), more likely to have left anterior descending artery (LAD) as the culprit artery (50 vs. 42%, p = 0.009), and poor pre-PCI (percutaneous coronary intervention) TIMI (thrombolysis in myocardial infarction) flow ≤1 (78 vs. 64%; p &lt; 0.001). There was no difference in all-cause mortality, non-fatal reinfarction, or hospitalization for heart failure at 30 days or at long-term follow-up. CMR imaging was performed on 726 patients. SMuRFless patients had larger acute infarct size (17 vs. 13%, p = 0.04) and a smaller myocardial salvage index (42 vs. 50%, p = 0.02). These differences were attenuated when the higher LAD predominance and/or TIMI 0-1 flow were included in the model.

Conclusion

Despite no difference in 30-day mortality, SMuRFless patients had a larger infarct size and a smaller myocardial salvage index following first-presentation STEMI. This association was mediated by a larger proportion of LAD culprits and poor TIMI flow pre-PCI.

Clinical trial registration

clinicaltrials.gov, unique identifier: NCT01435408 (DANAMI 3-iPOST and DANAMI 3-DEFER) and NCT01960933 (DANAMI 3-PRIMULTI).

Left Ventricular Remodeling after Myocardial Infarction: From Physiopathology to Treatment

Myocardial infarction (MI) is the leading cause of death and morbidity worldwide, with an incidence relatively high in developed countries and rapidly growing in developing countries. The most common cause of MI is the rupture of an atherosclerotic plaque with subsequent thrombotic occlusion in the coronary circulation. This causes cardiomyocyte death and myocardial necrosis, with subsequent inflammation and fibrosis. Current therapies aim to restore coronary flow by thrombus dissolution with pharmaceutical treatment and/or intravascular stent implantation and to counteract neurohormonal activation. Despite these therapies, the injury caused by myocardial ischemia leads to left ventricular remodeling; this process involves changes in cardiac geometry, dimension and function and eventually progression to heart failure (HF). This review describes the pathophysiological mechanism that leads to cardiac remodeling and the therapeutic strategies with a role in slowing the progression of remodeling and improving cardiac structure and function.

Global longitudinal strain and outcome after endoscopic mitral valve repair

Aims

Identification of heart failure (HF) patients with secondary mitral regurgitation (SMR) that benefit from mitral valve (MV) repair remains challenging. We have focused on the role of left ventricular global longitudinal strain (LV‐GLS) and reservoir left atrial longitudinal strain (LASr) for the prediction of long‐term survival and reverse remodelling in patients with SMR undergoing endoscopic MV repair.

Methods and results

The study population consisted of 110 patients (age 67 ± 11 years, 66% men) with symptomatic SMR undergoing isolated MV repair using a minimally invasive surgical approach. Speckle tracking‐derived LV‐GLS and LASr were assessed in apical views using vendor‐independent software. Over a median of 7.7 years (IQRs 2.9–11.2), 64 patients (58%) died. Significant reverse LV (↓ LVESVI >10 mL/m²), LA (↓ LAVI >10 mL/m²) remodelling or both were observed in 43 (39%), 37 (34%) and 19 (17%) patients, respectively. LV‐GLS (HR 0.68, 95% CI 0.58–0.79, P < 0.001) and LASr (HR 0.93, 95% CI 0.88–0.97, P < 0.01) but not LV ejection fraction (LVEF) and LA volume index (LAVi) emerged as independent predictors of all‐cause mortality in Cox regression analysis. LV‐GLS was the only independent predictor of LV reverse remodelling (OR 1.24, 95% CI 1.05–1.43, P < 0.001) whereas LAVi and LASr were both independent predictors of LA reverse remodelling (both P < 0.05). In patients with atrial fibrillation at baseline, only LASr was an independent predictor (P < 0.05) of LA reverse remodelling.

Conclusions

In patients with SMR undergoing endoscopic MV repair, LV‐GLS and LASr are independently associated with long‐term survival and reverse remodelling and may be helpful in selecting SMR patients who may benefit from this procedure.

Effect of IL-1 Blockade With Anakinra on Heart Failure Outcomes in Patients With Anterior Versus Nonanterior ST Elevation Myocardial Infarction

ABSTRACT

Patients with ST elevation myocardial infarction (STEMI) are at risk of future heart failure (HF), particularly those with anterior STEMI. Interleukin-1 (IL-1) is a key mediator of the inflammatory response, and its blockade has emerged as a potential therapeutic strategy to prevent HF events. The aim of this analysis was to explore the effects of anakinra, an IL-1 receptor antagonist, on HF outcomes based on anterior versus nonanterior location STEMI and to explore whether this effect is mediated through the amelioration of left ventricular systolic function and cardiac remodeling. We pooled data from 3 early phase randomized clinical trials. The primary end point was a composite of all-cause death and new-onset HF at 1-year follow-up. The left anterior descending coronary artery as culprit vessel was used to identify anterior STEMI. We included 139 patients, 47 (34%) with anterior STEMI and 92 (66%) with nonanterior STEMI. Anakinra significantly reduced the combined end point of death or new-onset HF in patients with anterior STEMI [4 (13%) vs. 7 (42%), log-rank P value = 0.049] and in patients with nonanterior STEMI [3 (6%) vs. 9 (24%), log-rank P value = 0.014]. We found no significant differences comparing anakinra versus placebo in interval changes in left ventricular ejection fraction and volumes in anterior and nonanterior STEMI. In conclusion, anakinra is associated with a reduction of HF events in patients with STEMI, irrespective of anterior or nonanterior location, or of changes in left ventricular ejection fraction or cardiac remodeling.

Heart Failure After ST-Elevation Myocardial Infarction: Beyond Left Ventricular Adverse Remodeling

ST-segment elevation myocardial infarction (STEMI) remains a significant source of morbidity and mortality worldwide. Despite advances in treatment leading to a significant reduction in the early complications and in-hospital mortality, a significant proportion of STEMI survivors develop heart failure (HF) at follow-up. The classic paradigm of HF after STEMI is one characterized by left ventricular adverse remodeling (LVAR) and encompasses the process of regional and global structural and functional changes that occur in the heart as a consequence of loss of viable myocardium, increased wall stress and neurohormonal activation, and results in HF with reduced ejection fraction (HFrEF). More recently, however, with further improvements in the treatment of STEMI the incidence and entity of LVAR appear to be largely reduced, yet the risk for HF following STEMI is not abolished and remains substantial, identifying a new paradigm by which patients with STEMI present with HF and preserved EF (HFpEF) characterized by reduction of diastolic or systolic reserve independent of LVAR.

Protective Value of Aspirin Loading Dose on Left Ventricular Remodeling After ST-Elevation Myocardial Infarction

Aims

Left ventricular (LV) remodeling after ST-elevation myocardial infarction (STEMI) is a complex process, defined as changes of LV volumes over time. CMR feature tracking analysis (CMR-FT) offers an accurate quantitative assessment of LV wall deformation and myocardial contractile function. This study aimed to evaluate the role of myocardial strain parameters in predicting LV remodeling and to investigate the effect of Aspirin (ASA) dose before primary coronary angioplasty (pPCI) on myocardial injury and early LV remodeling.

Methods and Results

Seventy-eight patients undergoing CMR, within 9 days from symptom onset and after 6 months, were enrolled in this cohort retrospective study. We divided the study population into three groups based on a revised Bullock's classification and we evaluated the role of baseline CMR features in predicting early LV remodeling. Regarding CMR strain analysis, worse global circumferential and longitudinal strain (GCS and GLS) values were associated with adverse LV remodeling. Patients were also divided based on pre-pPCI ASA dosage. Significant differences were detected in patients receiving ASA 500 mg dose before pPCI, which showed lower infarct size extent and better strain values compared to those treated with ASA 250 mg. The stepwise multivariate logistic regression analysis, adjusted for covariates, indicated that a 500 mg ASA dose remained an inverse independent predictor of early adverse LV remodeling.

Conclusion

GCS and GLS have high specificity to detect early LV adverse remodeling. We first reported a protective effect of ASA loading dose of 500 mg before pPCI on LV myocardial damage and in reducing early LV adverse remodeling.

A Noncontrast CMR Risk Score for Long-Term Risk Stratification in Reperfused ST-Segment Elevation Myocardial Infarction

OBJECTIVES

This study compared the prognostic value of a noncontrast CMR risk score for the composite of all-cause death, nonfatal myocardial infarction, and new congestive heart failure.

BACKGROUND

A cardiovascular magnetic resonance (CMR) risk score including left ventricular ejection fraction (LVEF), myocardial infarct (MI) size, and microvascular obstruction (MVO) was recently proposed to risk-stratify patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

The Eitel CMR risk score and GRACE (Global Registry of Acute Coronary Events) score were used as a reference (Score 1: acute MI size ≥19% LV, LVEF ≤47%, MVO >1.4% LV and GRACE score). MVO was replaced by intramyocardial hemorrhage (IMH) in Score 2 (acute MI size ≥19% LV, LVEF ≤47%, IMH, and GRACE score). Score 3 included only LVEF ≤45%, IMH, and GRACE score.

RESULTS

There were 370 patients in the derivation cohort and 234 patients in the validation cohort. In the derivation cohort, the 3 scores performed similarly and better than GRACE score to predict the 1-year composite endpoint with C-statistics of 0.83, 0.83, 0.82, and 0.74, respectively. In the validation cohort, there was good discrimination and calibration of score 3, with a C-statistic of 0.87 and P = 0.71 in a Hosmer-Lemeshow test for goodness of fit, on the 1-year composite outcome. Kaplan-Meier curves for 5-year composite outcome showed that those with LVEF ≤45% (high-risk) and LVEF >45% and IMH (intermediate-risk) had significantly higher cumulative events than those with LVEF >45% and no IMH (low-risk), log-rank tests: P = 0.02 and P = 0.03, respectively. The HR for the high-risk group was 2.3 (95% CI: 1.1-4.7) and for the intermediate-risk group was 2.0 (95% CI: 1.0-3.8), and these remained significant after adjusting for the GRACE score.

CONCLUSIONS

This noncontrast CMR risk score has performance comparable to an established risk score, and patients with STEMI could be stratified into low risk (LVEF >45% and no IMH), intermediate risk (LVEF >45% and IMH), and high risk (LVEF ≤45%). (A Trial of Low-dose Adjunctive alTeplase During prIMary PCI [T-TIME]; NCT02257294) (Detection and Significance of Heart Injury in ST Elevation Myocardial Infarction [BHF MR-MI]; NCT02072850).

Reducing Cardiac Injury during ST-Elevation Myocardial Infarction: A Reasoned Approach to a Multitarget Therapeutic Strategy

The significant reduction in ‘ischemic time’ through capillary diffusion of primary percutaneous intervention (pPCI) has rendered myocardial-ischemia reperfusion injury (MIRI) prevention a major issue in order to improve the prognosis of ST elevation myocardial infarction (STEMI) patients. In fact, while the ischemic damage increases with the severity and the duration of blood flow reduction, reperfusion injury reaches its maximum with a moderate amount of ischemic injury. MIRI leads to the development of post-STEMI left ventricular remodeling (post-STEMI LVR), thereby increasing the risk of arrhythmias and heart failure. Single pharmacological and mechanical interventions have shown some benefits, but have not satisfactorily reduced mortality. Therefore, a multitarget therapeutic strategy is needed, but no univocal indications have come from the clinical trials performed so far. On the basis of the results of the consistent clinical studies analyzed in this review, we try to design a randomized clinical trial aimed at evaluating the effects of a reasoned multitarget therapeutic strategy on the prevention of post-STEMI LVR. In fact, we believe that the correct timing of pharmacological and mechanical intervention application, according to their specific ability to interfere with survival pathways, may significantly reduce the incidence of post-STEMI LVR and thus improve patient prognosis.