High-sensitivity troponin T predicts infarct scar characteristics and adverse left ventricular function by cardiac magnetic resonance imaging early after reperfused acute myocardial infarction

Troponin level at presentation as a prognostic factor among patients presenting with non-ST-segment elevation myocardial infarction

BACKGROUND

Timely reperfusion within 120 min is strongly recommended in patients presenting with non-ST-segment myocardial infarction (NSTEMI) with very high-risk features. Evidence regarding the use of high-sensitivity cardiac troponin (hs-cTn) concentration upon admission for the risk-stratification of patients presenting with NSTEMI to expedite percutaneous coronary intervention (PCI) and thus potentially improve outcomes is limited.

METHODS

All patients admitted to a tertiary care center ICCU between July 2019 and July 2022 were included. Hs-cTnI levels on presentaion were recorded, dividing patients into quartiles based on baseline hs-cTnI. Association between initial hs-cTnI and all-cause mortality during up to 3 years of follow-up was studied.

RESULTS

A total of 544 NSTEMI patients with a median age of 67 were included. Hs-cTnI levels in each quartile were: (a) ≤122, (b) 123-680, (c) 681-2877, and (d) ≥2878 ng/L. There was no difference between the initial hs-cTnI level groups regarding age and comorbidities. A higher mortality rate was observed in the highest hs-cTnI quartile as compared with the lowest hs-cTnI quartile (16.2% vs. 7.35%, p = .03) with hazard ratio (HR) for mortality of 2.6 (95% confidence interval [CI]: 1.23-5.4; p = .012) in the unadjusted model, and HR of 2.06 (95% CI: 1.01-4.79; p = .047) with adjustment for age, gender, serum creatinine, and significant comorbidities.

CONCLUSIONS

Patients with NSTEMI and higher hs-cTnI levels upon admission faced elevated mortality risk. This underscores the need for further prospective investigations into early reperfusion strategies' impact on NSTEMI patients' mortality, based on admission troponin elevation.

Cardiac Troponin, Kidney Function, Heart Failure and Mortality After Myocardial Infarction in Patients With and Without Kidney Impairment

Cardiac troponins (cTn) are routinely measured for the diagnosis and prognosis of myocardial infarction (MI). The relation between troponin levels, estimated glomerular filtration rate (eGFR), postinfarction heart failure (HF), and mortality is unclear in patients with kidney impairment. This is a retrospective, cross-sectional study of patients presenting to the Emergency Department at a single tertiary center. Participants presenting with confirmed type I MI from January 1, 2019, to December 31, 2021, were analyzed from the Myocardial Ischemia National Audit Project database. Main outcomes were acute HF, measured using Killip class, and inpatient mortality. Peak cardiac troponin T (cTnT) level was a secondary outcome. Data on 2,815 patients (67±14 years, 28% female) were analyzed. Ordinal logistic regression analysis was used to test for predictors of increasing Killip class. Binary logistic regression was used to test for predictors of inpatient mortality. Analysis of a sub-sample matched for age and diabetes mellitus status showed increased mortality in patients with eGFR <60 ml/min/1.73 m2 (12.2% vs 4.4%, p <0.001). Multivariate predictors of acute HF included log-transformed peak cTnT, eGFR, body mass index (BMI), and diabetes mellitus status. Multivariate predictors of inpatient mortality included log-transformed peak cTnT, eGFR, age, BMI, and Killip class 3/4. On multivariate analysis, eGFR, ST-elevation MI diagnosis, BMI, male gender, diabetes mellitus status, and hypertension were all predictive of peak cTnT after MI. In conclusion, peak cTnT level and eGFR at presentation after MI are independent predictors of acute HF severity and death in patients with and without kidney impairment.

Heart failure as a complication of myocardial infarction: rational therapy. Case report

Heart failure (HF) is still a frequent complication of myocardial infarction. Timely identification of subjects at risk for HF development and early initiation of guideline-directed HF therapy in these patients, can decrease the HF burden. This article aims at summarizing clinical data on established pharmacological therapies in treating post-MI patients with left ventricular systolic dysfunction and signs and symptoms of HF.

Correlation of serial high-sensitivity cardiac Troponin T values to infarct mass determined by cardiac magnetic resonance imaging: a validation study

Aim

To validate correlations between contrast-enhanced magnetic resonance imaging (CE-MRI) infarct mass and high-sensitivity cardiac Troponin T (hs-cTnT) values at different time points in patients with confirmed acute myocardial infarction (AMI).

Methods and results

Patients presenting with AMI and with available CE-MRI between 1 January 2018 and 31 December 2020 were included. Correlation coefficients between hs-cTnT on admission, after 24, 48, 72, and 96 h, and peak hs-cTnT values and CE-MRI infarct mass were calculated. Correlations between hs-cTnT and CE-MRI infarct mass were compared with those of a third generation cTnT assay from a previously published study of our group. A total of 137 patients were included for the present analysis. Median CE-MRI infarct mass was 12,5 g [95% confidence interval (CI): 9.8–16.2 g]. Hs-cTnT values and infarct mass correlated well at all time points including admission (r = 0.474, 95% CI: 0.331–0.560, P &lt; 0.0001), 24 h (r = 0.508, 95% CI: 0.370–0.625, P &lt; 0.0001), 48 h (r = 0.547, 95% CI: 0.404–0.664, P &lt; 0.0001), 72 h (r = 0.489, 95% CI: 0.320–0.628, P &lt; 0.0001), 96 h (r = 0.509, 95% CI: 0.330–0.653, P &lt; 0.001) including peak hs-cTnT values (r = 0.547, 95% CI: 0.416–0.656, P &lt; 0.0001), and maximum absolute delta changes within 96 h (r = 0.507, 95% CI: 0.369–0.622, P &lt; 0.001). Correlations of the third generation assay could be confirmed for hs-cTnT at all time points. A superior correlation with CE-MRI infarct mass was observed for hs-cTnT values on admission.

Conclusion

Hs-cTnT values at different time points correlate well with CE-MRI infarct mass. Correlations of admission hs-cTnT values are superior to those of a third generation assay.

Clinically Acquired High Sensitivity Cardiac Troponin T is a Poor Predictor of Reduced Left Ventricular Ejection Fraction After ST Elevation Myocardial Infarction: A National Cohort Study-ANZACS-QI 65

OBJECTIVE

Cardiac troponins (cTn) have been used historically to estimate infarct size in ST elevation myocardial infarction (STEMI). Within a resource constrained health care environment, cTn could therefore be used for prioritisation of patients for cardiac imaging, in particular echocardiography. We aimed to determine how useful routinely collected cTn would be in predicting significant left ventricular (LV) impairment.

METHODS

All patients in the All New Zealand Acute Coronary Syndrome Quality Improvement (ANZACS-QI) registry with their first episode of STEMI between January 2013 and November 2018, who had high sensitivity troponin T measured, were included. We excluded patients with no left ventricular ejection fraction (LVEF) assessment, known LV dysfunction, or prior myocardial infarction.

RESULTS

In total, 3,698 patients were included in the analysis. A higher mean hsTnT (admission and peak) was seen in patients with more severely impaired LV function but there was significant overlap in the range of hsTnT between the different LVEF categories. Cardiac troponins demonstrated poor discriminative ability to either predict or exclude significant LV impairment (LVEF <40%). At an optimal cutpoint of 3,405 ng/L, peak hsTnT had a sensitivity of 56.5% (95% confidence interval [CI] 42-62%), a specificity of 65.3% (95% CI 62-79%) and an area under the receiver operating curve of 0.62 (95% CI 0.60-0.64).

CONCLUSION

This is the largest study comparing clinically measured troponin levels and LV function in patients presenting with STEMI. A definite, but weak, association was seen between peak troponin and the degree of LV dysfunction, with significant overlap in troponin levels between levels of myocardial dysfunction. Routinely acquired troponin is not suitable for clinical use as a method of prioritising patients for cardiac imaging.

Reperfusion After Fibrinolytic Therapy (RAFT): An open-label, multi-centre, randomised controlled trial of bivalirudin versus heparin in rescue percutaneous coronary intervention

BACKGROUND

The safety and efficacy profile of bivalirudin has not been examined in a randomised controlled trial of patients undergoing rescue PCI.

OBJECTIVES

We conducted an open-label, multi-centre, randomised controlled trial to compare bivalirudin with heparin ± glycoprotein IIb/IIIa inhibitors (GPIs) in patients undergoing rescue PCI.

METHODS

Between 2010-2015, we randomly assigned 83 patients undergoing rescue PCI to bivalirudin (n = 42) or heparin ± GPIs (n = 41). The primary safety endpoint was any ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) bleeding at 90 days. The primary efficacy endpoint was infarct size measured by peak troponin levels as a multiple of the local upper reference limit (Tn/URL). Secondary endpoints included periprocedural change in haemoglobin adjusted for red cells transfused, TIMI (Thrombolysis in Myocardial Infarction) bleeding, ST-segment recovery and infarct size determined by the Selvester QRS score.

RESULTS

The trial was terminated due to slow recruitment and futility after an interim analysis of 83 patients. The primary safety endpoint occurred in 6 (14%) patients in the bivalirudin group (4.8% GPIs) and 3 (7.3%) in the heparin ± GPIs group (54% GPIs) (risk ratio, 1.95, 95% confidence interval [CI], 0.52-7.3, P = 0.48). Infarct size was similar between the two groups (mean Tn/URL, 730 [±675] for bivalirudin, versus 984 [±1585] for heparin ± GPIs, difference, 254, 95% CI, -283-794, P = 0.86). There was a smaller decrease in the periprocedural haemoglobin level with bivalirudin than heparin ± GPIs (-7.5% [±15] versus -14% [±17], difference, -6.5%, 95% CI, -0.83-14, P = 0.0067). The rate of complete (≥70%) ST-segment recovery post-PCI was higher in patients randomised to heparin ± GPIs compared with bivalirudin.

CONCLUSIONS

Whether bivalirudin compared with heparin ± GPI reduces bleeding in rescue PCI could not be determined. Slow recruitment and futility in the context of lower-than-expected bleeding event rates led to the termination of this trial (ANZCTR.org.au, ACTRN12610000152022).

Cardiac magnetic resonance derived left atrial strain after ST-elevation myocardial infarction: an independent prognostic indicator

Background

The prognostic value of cardiac magnetic resonance (CMR) derived left atrial (LA) strain, ejection fraction (LAEF) and indexed volumes (LAVI_max and LAVI_min) after ST-elevation myocardial infarction (STEMI) remains controversial. The aim of this study was to assess the relationship between LA function and major adverse cardiovascular events (MACE) after STEMI.

Methods

A total of 202 prospectively recruited patients who underwent CMR at median day 4 after STEMI had complete CMR data for feature tracking assessment. LA reservoir and booster strain were quantified based on the average of three independently repeated measurements.

Results

MACE occurred in 35 patients during a median follow up of 607 days. Patients with MACE had lower median LA reservoir strain (18.9% vs. 29.4%, P<0.001), LA booster strain (9.4% vs. 13.0%, P=0.002) and LAEF (41.5% vs. 49.2%, P<0.001) than patients without MACE. Kaplan-Meier analyses demonstrated a difference in MACE between high- and low-risk groups for LA reservoir strain (cutoff 19.2%, P<0.001), LA booster strain (cutoff 9.7%, P<0.001) and LAEF (cutoff 38.5%, P<0.001). The AUC increased from 0.713 (95% CI: 0.608-0.818) for LVEF to 0.775 (95% CI: 0.680-0.870) when LA reservoir strain was added to LVEF (P=0.047). Univariate Cox regression analysis showed that all LA parameters had a significant effect on MACE, while multivariate analysis found LA reservoir strain was an independent predictor of MACE (HR 0.905; 95% CI: 0.843-0.972, P=0.006).

Conclusions

CMR derived LA reservoir strain independently predicted MACE after STEMI when adjusted for standard risk measures.

Overexpression of Activating Transcription Factor 3 Alleviates Cardiac Microvascular Ischemia/Reperfusion Injury in Rats

Activating transcription factor 3 (ATF3) has been confirmed to be responsive to oxidative stress and to negatively regulate the activity of Toll-like receptor 4 (TLR4). However, the effect of ATF3 on cardiac microvascular ischemia/reperfusion (I/R) injury remains unknown. The GEO2R online tool was employed to obtain differentially expressed genes GSE4105 and GSE122020, in two rat I/R injury microarray datasets. We established a rat myocardial I/R model in vivo, and also generated an in vitro hypoxia/reoxygenation (H/R) model of cardiomyoblast H9c2 cells. Overexpression of ATF3 was achieved by adenoviral-mediated gene transfer (Ad-ATF3). Rats were randomly divided into four groups: sham, I/R, I/R + Ad-Lacz (as a control), and I/R + Ad-ATF3. ELISA, CCK-8, DCFH-DA probe, qRT-PCR and Western blotting were used to determine the expression of ATF3, oxidative indices, cellular injury and TLR4/NF-κB pathway-associated proteins. Transmission electron microscopy, immunohistochemistry and immunofluorescence were used to detect the leukocyte infiltration and the alteration of microvascular morphology and function in vivo. Echocardiographic and hemodynamic data were also obtained. Bioinformatics analysis revealed that ATF3 was upregulated in I/R myocardia in two independent rat myocardial I/R models. Cardiac microvascular I/R injury included leukocyte infiltration, microvascular integrity disruption, and microvascular perfusion defect, which eventually resulted in the deterioration of hemodynamic parameters and heart function. Ad-ATF3 significantly restored microvascular function, increased cardiac microvascular perfusion, and improved hemodynamic parameters and heart function. Mechanistically, Ad-ATF3 ameliorated oxidative stress, inhibited TLR4/NF-κB pathway activation and down-regulated the expression of downstream proinflammatory cytokines in I/R myocardium in vivo and in H/R H9c2 cells in vitro. ATF3 overexpression protects against cardiac microvascular I/R injury in part by inhibiting the TLR4/NF-κB pathway and oxidative stress.

Heart failure after myocardial infarction: incidence and predictors

Aims

The aim of the present paper was to provide an up‐to‐date view on epidemiology and risk factors of heart failure (HF) development after myocardial infarction.

Methods and results

Based on literature review, several clinical risk factors and biochemical, genetic, and imaging biomarkers were identified to predict the risk of HF development after myocardial infarction.

Conclusions

Heart failure is still a frequent complication of myocardial infarction. Timely identification of subjects at risk for HF development using a multimodality approach, and early initiation of guideline‐directed HF therapy in these patients, can decrease the HF burden.

Usefulness of High Sensitivity Troponin T to Predict Long-Term Left Ventricular Dysfunction After ST-Elevation Myocardial Infarction

Guidelines recommend the use of transthoracic echocardiography (TTE) and clinical scores to risk stratify patients after ST-elevation myocardial infarction (STEMI). High sensitivity troponin T (hs-cTnT) is predictive of outcome after STEMI but the predictive value of hs-cTnT relative to other risk assessment tools has not been established. We aimed to compare the predictive value of hs-cTnT to other risk assessment tools in patients with STEMI. A subset of 578 patients with STEMI were included in this post-hoc study from the Third DANish Study of Optimal Acute Treatment of Patients with ST-segment Elevation Myocardial Infarction trial. Patients underwent cardiac magnetic resonance imaging (CMR) during index hospitalization as well as TTE at 1 year after their STEMI. The predictive value of hs-cTnT was compared with CKMB, infarct size (IS)/left ventricular ejection fraction (LVEF) assessed with CMR, LVEF assessed at discharge with TTE and the Global Registry of Acute Coronary Events (GRACE) and Thrombolysis in Myocardial Infarction (TIMI) risk-scores. The primary outcome was LV systolic dysfunction defined as LVEF ≤40% after 1 year on TTE. The area under the receiver operating characteristic curve analyses showed no significant difference between hs-cTnT and early CMR-assessed IS or LVEF in predicting subsequent LVEF ≤40%. Area under the curve for hs-cTnT was 0.82, 0.85 for IS (p = 0.22), and 0.87 for LVEF (p = 0.23). For predischarge TTE-assessed LVEF, the value was 0.85 (p = 0.45), 0.63 for creatine kinase-MB (p <0.001), 0.61 for the GRACE score (p <0.001), and 0.70 for the TIMI score (p = 0.02). A peak hs-cTnT value <3,500 ng/L ruled out LVEF ≤40% with probability of 98%. In conclusion, in patients presenting with STEMI undergoing PCI, hs-cTnT level strongly predicted long-term LV dysfunction and could be used as a clinical risk stratification tool to identify patients at high risk of progressing to LV dysfunction due to its general availability and high-predictive accuracy.

Incidence and predictors of left ventricular thrombus formation following acute ST-segment elevation myocardial infarction: A serial cardiac MRI study

Aims

Left ventricular (LV) thrombus is a complication of acute ST-segment elevation myocardial infarction (STEMI). We determined the incidence and predictors of LV thrombus formation using serial cardiac magnetic resonance (CMR) and two-dimensional echocardiography studies.

Methods and results

Two hundred and ten patients underwent CMR (median 4 days [IQR 3-7]) and transthoracic echocardiography (median 4 days [IQR 3-7]) early after STEMI presentation with serial follow-up CMR (median 55 days [IQR 46-64]) and echocardiography studies (median 54 days [IQR 45-64]) performed subsequently. The incidence of LV thrombus was 12.3% (26/210) by CMR and 6.2% (13/210) by two-dimensional echocardiography. Echocardiography had 50% sensitivity and 100% specificity for LV thrombus detection compared to CMR. LV thrombus was found in 23.6% of patients with anterior STEMI (22/93). Ischaemic stroke occurred in 1.4% of patients (3/210). Patients with LV thrombus had lower baseline LV ejection fraction (LVEF) (34.9% vs 47.4%, p < 0.001). Microvascular obstruction was more common in patients with LV thrombus (77% vs 39%, p < 0.001). Patients with LV thrombus had increased LV dimensions with larger LV end-diastolic (19 ml [IQR 9-44] vs 6 ml [IQR -4-18], p < 0.001) and end-systolic volumes (10 ml [IQR 0–22] vs -4 ml [IQR -12-4], p < 0.001).

Conclusion

CMR increases the detection of LV thrombi which standard echocardiography may underestimate. Serial studies post-STEMI may improve detection of LV thrombus, which is more prevalent in patients with anterior infarction, moderate LV dysfunction and adverse LV remodelling. This subgroup of patients may represent a high-risk group for targeted serial screening with CMR.

Diagnostic Roles of Postmortem cTn I and cTn T in Cardiac Death with Special Regard to Myocardial Infarction: A Systematic Literature Review and Meta-Analysis

Background: Cardiac troponin I (cTn I) and cardiac troponin T (cTn T) are currently widely used as diagnostic biomarkers for myocardial injury caused by ischemic heart diseases in clinical and forensic medicine. However, no previous meta-analysis has summarized the diagnostic roles of postmortem cTn I and cTn T. The aim of the present study was to meta-analyze the diagnostic roles of postmortem cTn I and cTn T for cardiac death in forensic medicine, present a systematic review of the previous literature, and determine the postmortem cut-off values of cTn I and cTn T. Methods: We searched multiple databases for the related literature, performed a meta-analysis to investigate the diagnostic roles of postmortem cardiac troponins, and analyzed the receiver operating characteristic (ROC) curve to determine their postmortem cut-off values. Results and Conclusions: The present meta-analysis demonstrated that postmortem cTn I and cTn T levels were increased in pericardial fluid and serum in cardiac death, especially in patients with acute myocardial infarction (AMI). We determined the postmortem cut-off value of cTn I in the pericardial fluid at 86.2 ng/mL, cTn I in serum at 9.5 ng/mL, and cTn T in serum at 8.025 ng/mL.

In vivo label-free optical monitoring of structural and metabolic remodeling of myocardium following infarction

Cardiac remodeling following myocardial infarction (MI) involves structural and functional alterations in the infarcted and remote viable myocardium that can ultimately lead to heart failure. The underlying mechanisms are not fully understood and, following our previous study of the autofluorescence lifetime and diffuse reflectance signatures of the myocardium in vivo at 16 weeks post MI in rats [Biomed. Opt. Express6(2), 324 (2015)], we here present data obtained at 1, 2 and 4 weeks post myocardial infarction that help follow the temporal progression of these changes. Our results demonstrate that both structural and metabolic changes in the heart can be monitored from the earliest time points following MI using label-free optical readouts, not only in the region of infarction but also in the remote non-infarcted myocardium. Changes in the autofluorescence intensity and lifetime parameters associated with collagen type I autofluorescence were indicative of progressive collagen deposition in tissue that was most pronounced at earlier time points and in the region of infarction. In addition to significant collagen deposition in infarcted and non-infarcted myocardium, we also report changes in the autofluorescence parameters associated with reduced nicotinamide adenine (phosphate) dinucleotide (NAD(P)H) and flavin adenine dinucleotide (FAD), which we associate with metabolic alterations throughout the heart. Parallel measurements of the diffuse reflectance spectra indicated an increased contribution of reduced cytochrome c. Our findings suggest that combining time-resolved spectrofluorometry and diffuse reflectance spectroscopy could provide a useful means to monitor cardiac function in vivo at the time of surgery.

Biomarker assessment for early infarct size estimation in ST-elevation myocardial infarction

BACKGROUND

High-sensitivity cardiac troponin T (hs-cTnT) represents the biomarker of choice for infarct size (IS) estimation in patients with acute ST-elevation myocardial infarction (STEMI). However, admission values of hs-cTnT are only weakly associated with IS. The aim of this study was to investigate the incremental value of different biomarkers measured on admission for IS estimation in STEMI patients.

METHODS

In this prospective observational study, we included 161 consecutive STEMI patients treated with primary percutaneous coronary intervention (pPCI). The following biomarkers were assessed on admission: hs-cTnT, N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and neutrophil/lymphocyte ratio (NLR). IS was determined by cardiac magnetic resonance (CMR) imaging 3 (Interquartile range [IQR] 2 to 4) days after the index event.

RESULTS

Patients with large IS (>19% of left ventricular myocardium) showed significantly higher levels of admission hs-cTnT (399.6 vs. 53.4 ng/L, p < .001), NT-pro-BNP (140 vs. 86 ng/L, p = .008) and NLR (6.4 vs. 4.1, p < .001). The combination of hs-cTnT, NT-pro-BNP and NLR on admission resulted in a significantly higher area under the curve (0.78; 95% CI 0.704 to 0.838, (p = .01)) for the prediction of large IS than admission hs-cTnT alone (0.69; 95% CI 0.619 to 0.767).

CONCLUSIONS

In STEMI patients undergoing pPCI, a comprehensive biomarker approach on admission including hs-cTnT, NT-pro-BNP and NLR was significantly better for immediate infarct severity estimation as compared to hs-cTnT alone.

Association Between Acute Inflammatory Response and Infarct Size in Stemi Patients Undergoing Primary PCI

Background: The inflammatory response of the immune system plays a major role in the period following an acute myocardial infarction (MI), as it coordinates the formation of the fibrous scar tissue that replaces the infarcted myocardial cells and ultimately leads to healing and remodeling of the affected zone. Along with other pro- and anti-inflammatory cytokines and acute phase proteins, interleukin-6 (IL-6) and C-reactive protein (CRP) are associated with the extent of the infarct size (IS) and may serve as predictors for remodeling and adverse left ventricular (LV) function. Material and methods: A single-center, non-randomized, observational prospective study was conducted, which included 75 patients with primary revascularized ST-elevation myocardial infarction (STEMI). High-sensitivity CRP (hs-CRP) serum levels were determined on day 1 and day 5 following the acute event. IL-6 was also determined on day 1. All patients underwent cardiac magnetic resonance imaging (CMR) at 1-month follow-up with determination of LV function and quantification of the scar tissue using late gadolinium enhancement imaging. The patients were divided into 2 groups based on baseline hs-CRP values. Results: Patients with higher baseline hs-CRP levels presented significantly higher infarct size (p = 0.0003), higher transmural extent (p <0.0001), lower LV ejection fraction (p = 0.0024), end-systolic (p = 0.0021) and end-diastolic (p = 0.0065) volumes. Small IS (<10%) recorded the lowest levels of hs-CRP, while IS >20% presented the highest levels of hs-CRP, at baseline and day 5 (p = 0.4 and 0.001). IL-6 levels were also associated with the magnitude of infarct scar: 2.17 pg/mL for IS <10%, 15.52 pg/mL for IS between 10% and 20%, and 24.52 pg/mL for IS >20%, p = 0.002. Conclusion: hs-CRP and IL-6 serum levels following an MI are correlated with IS, transmurality extent of the scar tissue, as well as with altered systolic and diastolic LV function determined by CMR at 1-month follow-up.

The impact of incomplete revascularization on early and late outcomes in ST-elevation myocardial infarction

BACKGROUND

In ST-elevation myocardial infarction (STEMI) in patients with multivessel disease, there is a lack of consensus regarding the importance of complete revascularization and the timing of treatment of nonculprit stenoses. Our objective was to investigate the impact of incomplete revascularization in STEMI patients using the residual Synergy Between PCI with TAXUS and Cardiac Surgery score (rSS) to define completeness of revascularization.

METHODS

This study examined associations between incomplete revascularization, determined by the rSS, and the combined outcome of cardiac death and myocardial infarction (MI). Patients were divided into groups: rSS = 0 (complete revascularization), rSS = 1-8 (incomplete revascularization with a low burden of residual disease), or rSS >8 (incomplete revascularization with a high burden of residual disease).

RESULTS

The rSS score was calculated in 589 consecutive patients; 25% had an rSS of 0, 42% rSS 1-8, and 33% rSS >8. At median follow-up of 3.5 years, cardiac death and MI occurred in 5% of rSS = 0 patients, 15% rSS = 1-8, and 26% with rSS >8 (P < .001). The rSS was powerful independent predictor of cardiac death and MI (hazard ratio 5.05, CI 2.89-12.00, rSS >8 vs rSS 0, P < .001 and hazard ratio 2.96, CI 1.31-6.69, rSS = 1-8 vs rSS = 0, P = .009), respectively, and an independent predictor of mortality, MI, unplanned revascularization, and major adverse cardiovascular events.

CONCLUSIONS

In patients with STEMI, the rSS independently predicts cardiac death and MI. Patients with an rSS >8 had substantially higher rates of cardiac death or MI. The rSS can be used to define incomplete revascularization in STEMI and predict adverse outcomes.

Predictive Value of High-Sensitivity Troponin T for Systolic Dysfunction and Infarct Size (Six Months) After ST-Elevation Myocardial Infarction

The association of markers of myocardial injury and dysfunction with infarct size (IS) and ejection fraction (EF) are well documented. However, limited data are available on the newer high-sensitivity troponin assays and comparison with morphologic and functional assessment with cardiac magnetic resonance imaging. We aimed to examine the associations of high-sensitivity cardiac Troponin-T (hs-cTnT), creatine kinase MB iso-enzyme (CKMB), and N-terminal pro B-type Natriuretic Peptide (NT-proBNP) to IS and EF at 6 months. Blood samples from 119 ST-segment elevation myocardial infarction patients from the Rapid Endovascular Catheter Core Cooling Combined With Cold Saline solution as an Adjunct to Percutaneous Coronary Intervention for the Treatment of Acute Myocardial Infarction trial were collected at baseline, 6, 24, and 48 hours after admission. Cardiac magnetic resonance was performed at 4 ± 2 days and 6 months. The association of biomarker levels to IS and EF was tested with Pearson's correlation coefficients and linear regression models with bootstrap resampling. The correlation coefficient of biomarker to IS was (CKMB: r = 0.71); (NT-proBNP: r = 0.55); (hs-cTnT: r = 0.80); and for EF (CKMB: r = 0.57); (NT-proBNP: r = 0.48); and (peak hs-cTnT: r = 0.68). IS and EF at 4 ± 2 days had the strongest correlations with IS and EF at 6 months respectively (IS: r = 0.84) and (EF: r = 0.74). Receiver operating characteristic of peak hs-cTnT for predicting EF ≤40% at 6 months was 0.87 compared with 0.75 for early IS. Early EF was a negative predictor of late EF <40%, 1-area under curve = 0.93. In conclusion, high-sensitivity Troponin T is a rapid, cheap, generally available tool for accurate prediction of systolic dysfunction in patients 6 months after first-time ST-segment elevation myocardial infarction.

High-sensitivity cardiac troponin T, left ventricular function, and outcome in non-ST elevation acute coronary syndrome

BACKGROUND

Cardiac troponin (cTn) levels reflect infarct size and depressed left ventricular ejection fraction (LVEF) in patients with non-ST elevation acute coronary syndrome (NSTE-ACS). However, there is very limited information on whether cTn measured with a high-sensitivity (hs) assay would provide incremental prognostic information to the LVEF in NSTE-ACS patients.

METHODS

This was a registry-based study (SWEDEHEART registry) investigating 20,652 NSTE-ACS patients with available information on hs-cTnT (highest level recorded during the hospitalization) and the LVEF estimated using echocardiography. All patients had been followed for 1 year.

RESULTS

Hs-cTnT levels independently predicted major cardiovascular events (MACE) in cohorts with normal, slightly depressed, moderately depressed, and severely depressed LVEF. The adjusted hazard ratios in these cohorts were 1.18 (95% CI 1.13-1.23), 1.12 (95% CI 1.06-1.18), 1.12 (95% CI 1.06-1.19), and 1.21 (95% CI 1.13-1.30), respectively. Hs-cTnT levels were particularly predictive for cardiovascular mortality and readmission for heart failure. Excluding patients with previous cardiac disease did not affect the overall interrelations of hs-cTnT and LVEF with MACE.

CONCLUSIONS

Hs-cTnT levels provide incremental prognostic value independent of the LVEF in patients with NSTE-ACS. Hs-cTnT is particularly predictive for MACE in patients with severely depressed LVEF but also in those with a normal LVEF. Accordingly, a normal LVEF should not be used as an argument not to target patients to thorough workup.

High-sensitivity cardiac troponin I and risk of heart failure in patients with suspected acute coronary syndrome: a cohort study

Aims

Heart failure may occur following acute myocardial infarction, but with the use of high-sensitivity cardiac troponin assays we increasingly diagnose patients with minor myocardial injury. Whether troponin concentrations remain a useful predictor of heart failure in patients with acute coronary syndrome is uncertain.

Methods and results

We identified all consecutive patients (n = 4748) with suspected acute coronary syndrome (61 ± 16 years, 57% male) presenting to three secondary and tertiary care hospitals. Cox-regression models were used to evaluate the association between high-sensitivity cardiac troponin I concentration and subsequent heart failure hospitalization. C-statistics were estimated to evaluate the predictive value of troponin for heart failure hospitalization. Over 2071 years of follow-up there were 83 heart failure hospitalizations. Patients with troponin concentrations above the upper reference limit (URL) were more likely to be hospitalized with heart failure than patients below the URL (118/1000 vs. 17/1000 person years, adjusted hazard ratio: 7.0). Among patients with troponin concentrations

Conclusion

Cardiac troponin is an excellent predictor of heart failure hospitalization in patients with suspected acute coronary syndrome. The strongest associations were observed in patients with troponin concentrations in the normal reference range, in whom high-sensitivity cardiac troponin assays identify those at increased risk of heart failure who may benefit from further investigation and treatment.

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Key Words

• Acute coronary syndrome
• Heart failure
• High-sensitivity cardiac troponin

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MESH Headings

• Acute Coronary Syndrome/blood
• Acute Coronary Syndrome/complications
• Acute Coronary Syndrome/diagnosis
• Aged
• Biomarkers/blood
• Female
• Heart Failure/blood
• Heart Failure/etiology
• Humans
• Male
• Middle Aged
• Predictive Value of Tests
• Prognosis
• Risk Factors
• Troponin I/blood

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Grants

• 201492/Z/16/Z Wellcome Trust
• FS/16/75/32533 British Heart Foundation
• SP/12/10/29922 British Heart Foundation
• SP/12/10/29922 British Heart Foundation
• HICG/1/40 Chief Scientist Office
• FS/16/14/32023 British Heart Foundation
• PG/15/51/31596 British Heart Foundation

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Affiliation(s)

Dominik Stelzle BHF Centre for Cardiovascular Science, University of Edinburgh, 49 Little Fracne Cresc, Edinburgh EH16 4SB, UK
Anoop S V Shah BHF Centre for Cardiovascular Science, University of Edinburgh, 49 Little Fracne Cresc, Edinburgh EH16 4SB, UK
Atul Anand BHF Centre for Cardiovascular Science, University of Edinburgh, 49 Little Fracne Cresc, Edinburgh EH16 4SB, UK
Fiona E Strachan BHF Centre for Cardiovascular Science, University of Edinburgh, 49 Little Fracne Cresc, Edinburgh EH16 4SB, UK
Andrew R Chapman BHF Centre for Cardiovascular Science, University of Edinburgh, 49 Little Fracne Cresc, Edinburgh EH16 4SB, UK
Martin A Denvir BHF Centre for Cardiovascular Science, University of Edinburgh, 49 Little Fracne Cresc, Edinburgh EH16 4SB, UK
Nicholas L Mills BHF Centre for Cardiovascular Science, University of Edinburgh, 49 Little Fracne Cresc, Edinburgh EH16 4SB, UK
David A McAllister The Institute of Health and Wellbeing, University of Glasgow, Glasgow, UK The Usher Institute of Population Health and Informatics, University of Edinburgh, Edinburgh, UK

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Clinical predictors for the manifestation of late gadolinium enhancement after acute myocardial infarction

Despite prompt revascularization, some patients with acute myocardial infarction (AMI) develop myocardial scars, which can be visualized by late gadolinium enhancement (LGE) in cardiovascular magnetic resonance imaging (CMR). Our goal was to identify angiographic findings that were predictive for scar development in patients after reperfused AMI.We examined 136 patients after first ST-elevated myocardial infarction by CMR after a median of 4 days (range: 2-7). Patients with manifestation of LGE were matched to patients without LGE by means of age and gender. Clinical follow-up with a combined primary endpoint including myocardial reinfarction, congestive heart failure, stroke, death and development of left ventricular thrombus was reported after 24 months.Patients with manifestation of LGE had a significant longer time of symptom-to-intervention, a higher prevalence of anterior AMI, and more proximal culprit lesions. Furthermore, left ventricular ejection fraction was significantly decreased, and peak values of infarct markers were significantly higher in these patients. Preinterventional thrombolysis in myocardial infarction-0-flow was significantly more frequent in patients with LGE manifestation. The presence of 3-vessel disease (odds ratio 53.99, 95% confidence interval 8.22-354.63, P <.001), a proximal culprit lesion, and high creatine kinase myocardial band (CK-MB) values were identified as independent predictors of LGE. Follow-up demonstrated a higher incidence of clinical events in the group with LGE, with the most common cause of heart failure (38.2% vs 7.4%, P <.001).The extent of angiographic findings in AMI plays a major role in the manifestation of LGE. The presence of a multivessel disease, a proximal culprit lesion, and high values of CK-MB are strong independent predictors for LGE manifestation.

Monocyte-derived circulating microparticles (CD14+, CD14+/CD11b+ and CD14+/CD142+) are related to long-term prognosis for cardiovascular mortality in STEMI patients

BACKGROUND

Circulating microparticles (cMPs) have been proposed as novel biomarkers of cardiovascular disease (CVD). We aimed to investigate the prognostic relevance of cMPs for future major adverse cardiovascular events (MACE) in STEMI patients.

METHODS

We included 200 STEMI patients treated with percutaneous coronary intervention (PCI). One hundred patients with a primary composite end point (recurrent nonfatal acute MI, rehospitalization for heart failure, unscheduled PCI or death because of CV causes) were case-matched for sex, age, and CVD risk factors to 100 patients without a primary endpoint at the end of study follow-up (4.4 (1.4) years). cMPs from vascular cells were measured by flow cytometer at a mean of 28h after onset of symptoms.

RESULTS

No differences were observed in MP shedding between patients with or without a MACE at the end of the study follow-up. However, compared to patients who survived during follow-up, patients who died because of CV causes (n=24) presented with increased total cMPs (Annexin V-AV-⁺), cMPs carrying tissue factor, and increased MP shedding from platelets, lymphocytes, monocytes, and activated leukocytes, and ~10% lower left ventricular ejection fraction (LVEF). ROC-curve analyses showed that monocyte-derived cMPs (CD14⁺/AV⁺, CD11b⁺/CD14⁺/AV⁺ and CD142⁺/CD14⁺/AV⁺) considered together with LVEF best predicted cardiovascular mortality.

CONCLUSIONS

Monocyte-derived cMPs assessed in the acute phase relate to the prognosis of CV death at the long term. These findings may be of clinical interest in the risk assessment of STEMI patients.

Adverse diastolic remodeling after reperfused ST-elevation myocardial infarction: An important prognostic indicator

OBJECTIVES

We sought to determine the relationship of adverse diastolic remodeling (ie, worsening diastolic or persistent restrictive filling) with infarct scar characteristics, and to evaluate its prognostic value after ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

Severe diastolic dysfunction (restrictive filling) has known prognostic value post STEMI. However, ongoing left ventricular (LV) remodeling post STEMI may alter diastolic function even if less severe.

METHODS AND RESULTS

There were 218 prospectively recruited STEMI patients with serial echocardiograms (transthoracic echocardiography) and cardiac magnetic resonance imaging (CMR) performed, at a median of 4 days (early) and 55 days (follow-up). LV ejection fraction and infarct characteristics were assessed by CMR, and comprehensive diastolic function assessment including a diastolic grade was evaluated on transthoracic echocardiography. 'Adverse diastolic remodeling' occurred if diastolic function grade either worsened (≥1 grade) between early and follow-up imaging, or remained as persistent restrictive filling at follow-up. Follow-up infarct scar size (IS) predicted adverse diastolic remodeling (area under the curve 0.86) and persistent restrictive filling (area under the curve 0.89). The primary endpoint of major adverse cardiovascular events (MACE) occurred in 48 patients during follow-up (mean, 710±79 days). Kaplan-Meier analysis showed that adverse diastolic remodeling (n=50) and persistent restrictive filling alone (n=33) were significant predictors of MACE (both P<.001). Multivariate Cox analysis, when adjusted for TIMI risk score and CMR IS, microvascular obstruction, and LV ejection fraction, showed adverse diastolic remodeling (HR 3.79, P<.001) was an independent predictor of MACE, as was persistent restrictive filling alone (HR 2.61, P=.019).

CONCLUSIONS

Larger IS is associated with adverse diastolic remodeling. Following STEMI, adverse diastolic remodeling is a powerful prognostic marker, and identifies a larger group of 'at-risk' patients, than does persistent restrictive filling alone.

A Novel and Practical Screening Tool for the Detection of Silent Myocardial Infarction in Patients With Type 2 Diabetes

OBJECTIVE

Silent myocardial infarction (MI) is a prevalent finding in patients with type 2 diabetes and is associated with significant mortality and morbidity. Late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR) is the most validated technique for detection of silent MI, but is time-consuming, costly, and requires administration of intravenous contrast. We therefore planned to develop a simple and low-cost population screening tool to identify those at highest risk of silent MI validated against the CMR reference standard.

METHODS

A total of 100 asymptomatic patients with type 2 diabetes underwent electrocardiogram (ECG), echocardiography, biomarker assessment, and CMR at 3.0T including assessment of left ventricular ejection fraction and LGE. Global longitudinal strain from two- and four-chamber cines was measured using feature tracking.

RESULTS

A total of 17/100 patients with no history of cardiovascular disease had silent MI defined by LGE in an infarct pattern on CMR. Only four patients with silent MI had Q waves on ECG. Patients with silent MI were older (65 vs 60, P = .05), had lower E/A ratio (0.75 vs 0.89, P = .004), lower GLS (-15.2% vs -17.7%, P = .004), and higher amino-terminal pro brain natriuretic peptide (106 ng/L vs 52 ng/L, P = .003). A combined risk score derived from these four factors had an area under the receiver operating characteristic curve of 0.823 (0.734-0.892), P < .0001. A score of more than 3/5 had 82% sensitivity and 72% specificity for silent MI.

CONCLUSIONS

Using measures that can be derived in an outpatient clinic setting, we have developed a novel screening tool for the detection of silent MI in type 2 diabetes. The screening tool had significantly superior diagnostic accuracy than current ECG criteria for the detection of silent MI in asymptomatic patients.

Novel biomarkers predicting cardiac function after acute myocardial infarction

BACKGROUND

Measurement of biomarkers provides a cost-effective and widely available method to estimate cardiac dysfunction and clinical outcome of patients with acute myocardial infarction (AMI).

SOURCES OF DATA

PubMed entries with terms 'myocardial infarction' and the respective biomarker.

AREAS OF AGREEMENT

Cardiac troponins and natriuretic peptides are closely related to left ventricular dysfunction and the occurrence of adverse clinical events following AMI.

AREAS OF CONTENTION

The incremental value of novel biomarkers is controversial.

FUTURE DIRECTIONS

The combination of traditional and novel biomarkers might further improve risk stratification of patients with AMI.

SEARCH STRATEGY

We searched all entries on the PubMed database with the MeSH terms 'myocardial infarction' and 'cardiac troponins', 'natriuretic peptides', 'copeptin', galectin-3', 'corin', 'fetuin-A', 'adiponectin' and 'microRNA'.

Prognostic value of high sensitivity troponin T after ST-segment elevation myocardial infarction in the era of cardiac magnetic resonance imaging

Aims

To determine if high sensitivity troponin T (hs-TnT) measurements performed during the 'plateau phase' of troponin release (≥48 h) following ST-segment elevation myocardial infarction (STEMI) can predict major adverse cardiovascular endpoints (MACE), and to evaluate its prognostic value compared with cardiac magnetic resonance imaging (CMRI) parameters.

Methods and results

We prospectively recruited 201 first presentation STEMI patients. Serial hs-TnT levels were measured at admission, peak (highest), 24, 48 and 72 h. CMRI and transthoracic echocardiography were performed (4 days median) post-STEMI, evaluating infarct scar characteristics and left ventricular ejection fraction (LVEF). Associations were determined between hs-TnT levels and CMRI parameters early after STEMI with MACE (comprising mortality, re-infarction, new or worsening of heart failure, cerebrovascular accident, and sustained ventricular arrhythmias) at medium-term follow-up. After 602 days (median), 33 (17%) patients had MACE. Upper tertile hs-TnT levels at 48 and 72 h were associated with MACE (Kaplan-Meier P = 0.002 and P = 0.012, respectively). Multivariate Cox analyses, incorporating diabetes, CMRI scar size, LVEF and hs-TnT levels (applied at a single hs-TnT time point) showed that 48 and 72 h hs-TnT levels were independent predictors for MACE (HR = 1.20, P = 0.002, and HR = 1.21, P = 0.035 respectively).

Conclusion

Measurement of hs-TnT in the plateau phase after STEMI is an inexpensive method of prognostic risk assessment.