Unwrapping phase contrast MRI by iterative graph cuts.

PURPOSE: To develop and evaluate a phase unwrapping method for cine phase contrast MRI based on graph cuts. METHODS: A proposed Iterative Graph Cuts method was evaluated in 10 cardiac patients with two-dimensional flow quantification which was repeated at low venc settings to provoke wrapping. The images were also unwrapped by a path-following method (ROMEO), and a Laplacian-based method (LP). Net flow was quantified using semi-automatic vessel segmentation. High venc images were also wrapped retrospectively to asses the residual amount of wrapped voxels. RESULTS: The absolute net flow error after unwrapping at venc = 100 cm/s was 1.8 mL, which was 0.83 mL smaller than for LP. The repeatability error at high venc without unwrapping was 2.5 mL. The error at venc = 50 cm/s was 7.5 mL, which was 8.2 mL smaller than for ROMEO and 5.7 mL smaller than for LP. For retrospectively wrapped images with synthetic venc of 100/50/25 cm/s, the residual amount of wrapped voxels was 0.00/0.12/0.79%, which was 0.09/0.26/8.0 percentage points smaller than for LP. With synthetic venc of 25 cm/s, omitting magnitude information resulted in 3.2 percentage points more wrapped voxels, and only spatial/temporal unwrapping resulted in 4.6/21 percentage points more wrapped voxels compared to spatiotemporal unwrapping. CONCLUSION: Iterative Graph Cuts enables unwrapping of cine phase contrast MRI with very small errors, except for at extreme blood velocities, with equal or better performance compared to ROMEO and LP. The use of magnitude information and spatiotemporal unwrapping is recommended.

Diagnosis of left ventricular hypertrophy using non-ECG-gated 15O-water PET.

AIM: To develop a method for diagnosing left ventricular (LV) hypertrophy from cardiac perfusion 15O-water positron emission tomography (PET). METHODS: We retrospectively pooled data from 139 subjects in four research cohorts. LV remodeling patterns ranged from normal to severe eccentric and concentric hypertrophy. 15O-water PET scans (n = 197) were performed with three different PET devices. A low-end scanner (66 scans) was used for method development, and remaining scans with newer devices for a blinded evaluation. Dynamic data were converted into parametric images of perfusable tissue fraction for semi-automatic delineation of the LV wall and calculation of LV mass (LVM) and septal wall thickness (WT). LVM and WT from PET were compared to cardiac magnetic resonance (CMR, n = 47) and WT to 2D-echocardiography (2DE, n = 36). PET accuracy was tested using linear regression, Bland-Altman plots, and ROC curves. Observer reproducibility were evaluated using intraclass correlation coefficients. RESULTS: High correlations were found in the blinded analyses (r ≥ 0.87, P < 0.0001 for all). AUC for detecting increased LVM and WT (> 12 mm and > 15 mm) was ≥ 0.95 (P < 0.0001 for all). Reproducibility was excellent (ICC ≥ 0.93, P < 0.0001). CONCLUSION: 15O-water PET might detect LV hypertrophy with high accuracy and precision.

Randomized evaluation of beta blocker and ACE-inhibitor/angiotensin receptor blocker treatment in patients with myocardial infarction with non-obstructive coronary arteries (MINOCA-BAT): Rationale and design.

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is common and occurs in 6-8% of all patients fulfilling the diagnostic criteria for acute myocardial infarction (AMI). This paper describes the rationale behind the trial 'Randomized Evaluation of Beta Blocker and ACE-Inhibitor/Angiotensin Receptor Blocker Treatment (ACEI/ARB) of MINOCA patients' (MINOCA-BAT) and the need to improve the secondary preventive treatment of MINOCA patients. METHODS: MINOCA-BAT is a registry-based, randomized, parallel, open-label, multicenter trial with 2:2 factorial design. The primary aim is to determine whether oral beta blockade compared with no oral beta blockade, and ACEI/ARB compared with no ACEI/ARB, reduce the composite endpoint of death of any cause, readmission because of AMI, ischemic stroke or heart failure in patients discharged after MINOCA without clinical signs of heart failure and with left ventricular ejection fraction ≥40%. A total of 3500 patients will be randomized into four groups; e.g. ACEI/ARB and beta blocker, beta blocker only, ACEI/ARB only and neither ACEI/ARB nor beta blocker, and followed for a mean of 4 years. SUMMARY: While patients with MINOCA have an increased risk of serious cardiovascular events and death, whether conventional secondary preventive therapies are beneficial has not been assessed in randomized trials. There is a limited basis for guideline recommendations in MINOCA. Furthermore, studies of routine clinical practice suggest that use of secondary prevention therapies in MINOCA varies considerably. Thus results from this trial may influence future treatment strategies and guidelines specific to MINOCA patients.

Diagnosing type 2 myocardial infarction in clinical routine. A validation study.

Objective. Since 2010, myocardial infarction (MI) patients reported to the Swedish registry for MI (SWEDEHEART) are routinely classified into MI subtypes. The registry has been used to study the type 2 MI population but the MI-classification in the registry has not previously been validated. The aim of this study was to validate the type 2 MI classification in the registry. Design. A total of 772 patients diagnosed with MI in 2011 and reported to the SWEDEHEART registry were included in the study. All patients were retrospectively classified into MI type 1-5 or myocardial injury by independent reviewers strictly adhering to The Third Universal Definition of MI. This gold standard classification was compared with the classification in the registry. Results. Forty-eight (6.2%) patients were classified as type 2 MI in the registry compared with 93 (12.0%) according to the gold standard classification. A type 2 MI diagnosis was confirmed in 30 out of the 48 type 2 MI patients in the registry (PPV: 62.5%). There was a moderate rate of agreement (κ: 0.43) between the gold standard classification and the classification in SWEDEHEART in deciding a type 2 MI diagnosis. Conclusion. The SWEDEHEART registry agreed moderately with the gold standard in classifying patients with type 2 MI diagnosis. Thus, studies on patients with type 2 MI in the registry should be interpreted with caution. Since the prevalence of type 2 MI is substantially underestimated in SWEDEHEART, the registry should not be used to study the prevalence of type 2 MI.

Medical Therapy for Secondary Prevention and Long-Term Outcome in Patients With Myocardial Infarction With Nonobstructive Coronary Artery Disease.

BACKGROUND: Myocardial infarction with nonobstructive coronary arteries (MINOCA) occurs in 5% to 10% of all patients with myocardial infarction. Clinical trials of secondary prevention treatment in MINOCA patients are lacking. Therefore, the aim of this study was to examine the associations between treatment with statins, renin-angiotensin system blockers, ß-blockers, dual antiplatelet therapy, and long-term cardiovascular events. METHODS: This is an observational study of MINOCA patients recorded in the SWEDEHEART registry (the Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapy) between July 2003 and June 2013 and followed until December 2013 for outcome events in the Swedish Cause of Death Register and National Patient Register. Of 199 162 myocardial infarction admissions, 9466 consecutive unique patients with MINOCA were identified. Among those, the 9136 patients surviving the first 30 days after discharge constituted the study population. Mean age was 65.3 years, and 61% were women. No patient was lost to follow-up. A stratified propensity score analysis was performed to match treated and untreated groups. The association between treatment and outcome was estimated by comparing between treated and untreated groups by using Cox proportional hazards models. The exposures were treatment at discharge with statins, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, ß-blockers, and dual antiplatelet therapy. The primary end point was major adverse cardiac events defined as all-cause mortality, hospitalization for myocardial infarction, ischemic stroke, and heart failure. RESULTS: At discharge, 84.5%, 64.1%, 83.4%, and 66.4% of the patients were on statins, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, ß-blockers, and dual antiplatelet therapy, respectively. During the follow-up of a mean of 4.1 years, 2183 (23.9%) patients experienced a major adverse cardiac event. The hazard ratios (95% confidence intervals) for major adverse cardiac events were 0.77 (0.68-0.87), 0.82 (0.73-0.93), and 0.86 (0.74-1.01) in patients on statins, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, and ß-blockers, respectively. For patients on dual antiplatelet therapy followed for 1 year, the hazard ratio was 0.90 (0.74-1.08). CONCLUSIONS: The results indicate long-term beneficial effects of treatment with statins and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers on outcome in patients with MINOCA, a trend toward a positive effect of ß-blocker treatment, and a neutral effect of dual antiplatelet therapy. Properly powered randomized clinical trials to confirm these results are warranted.

Prognosis in relation to high-sensitivity cardiac troponin T levels in patients with myocardial infarction and non-obstructive coronary arteries.

BACKGROUND: Myocardial infarction (MI) with non-obstructive coronary arteries (MINOCA) is a recently recognized condition where biomarkers and prognosis are less well studied than in MI with obstructive coronary artery disease (MI-CAD). We therefore aimed to investigate the one-year prognostic value of high-sensitivity cardiac troponin T (hs-cTnT) levels in MINOCA in comparison to MI-CAD. METHODS: In this registry-based cohort study, we used data from patients with a discharge diagnosis of MI, admitted between 2009 and 2013 to Swedish hospitals using the hs-cTnT assay. Only patients without previously known coronary artery disease were considered. Patients with and without coronary stenosis >50% were regarded to have MI-CAD and MINOCA, respectively. Assessed outcomes included all-cause mortality, cardiovascular (CV) mortality and major CV events (MACE), defined as the composite of CV death or admissions for non-fatal MI, heart failure (HF) or ischemic stroke. RESULTS: The study cohort consisted of 1639 MINOCA and 17,304 MI-CAD patients. In adjusted analyses, hs-cTnT (ln) in MINOCA patients predicted all-cause mortality (HR 1.32 [95% CI 1.11-1.56]), CV mortality (HR 2.11 [95% CI 1.51-2.96]) and MACE (HR 1.44 [95% CI 1.20-1.72]). Hs-cTnT (ln) also predicted readmissions for HF (HR 1.51 [95% CI 1.51-2.96]) but not non-fatal MI or stroke. Interaction analyses suggested that hs-cTnT (ln) was at least as prognostic in patients with MINOCA compared to MI-CAD. CONCLUSIONS: Hs-cTnT levels in MINOCA patients are strong and independent predictors of adverse outcome. Consideration of hs-cTnT levels is important for risk assessment of MINOCA patients.

Effects of Oral Supplementation With Nitrate-Rich Beetroot Juice in Patients With Pulmonary Arterial Hypertension-Results From BEET-PAH, an Exploratory Randomized, Double-Blind, Placebo-Controlled, Crossover Study.

BACKGROUND: The nitrate-nitrite-nitric oxide (NO) pathway may represent a potential therapeutic target in patients with pulmonary arterial hypertension (PAH). We explored the effects of dietary nitrate supplementation, with the use of nitrate-rich beetroot juice (BRJ), in patients with PAH. METHODS AND RESULTS: We prospectively studied 15 patients with PAH in an exploratory randomized, double-blind, placebo-controlled, crossover trial. The patients received nitrate-rich beetroot juice (∼16 mmol nitrate per day) and placebo in 2 treatment periods of 7 days each. The assessments included; exhaled NO and NO flow-independent parameters (alveolar NO and bronchial NO flux), plasma and salivary nitrate and nitrite, biomarkers and metabolites of the NO-system, N-terminal pro-B-type natriuretic peptide, echocardiography, ergospirometry, diffusing capacity of the lung for carbon monoxide, and the 6-minute walk test. Compared with placebo ingestion of BRJ resulted in increases in; fractional exhaled NO at all flow-rates, alveolar NO concentrations and bronchial NO flux, and plasma and salivary levels of nitrate and nitrite. Plasma ornithine levels decreased and indices of relative arginine availability increased after BRJ compared to placebo. A decrease in breathing frequency was observed during ergospirometry after BRJ. A tendency for an improvement in right ventricular function was observed after ingestion of BRJ. In addition a tendency for an increase in the peak power output to peak oxygen consumption ratio (W peak/VO2 peak) was observed, which became significant in patients reaching an increase of plasma nitrite >30% (responders). CONCLUSIONS: BRJ administered for 1 week increases pulmonary NO production and the relative arginine bioavailability in patients with PAH, compared with placebo. An increase in the W peak/VO2 peak ratio was observed after BRJ ingestion in plasma nitrite responders. These findings indicate that supplementation with inorganic nitrate increase NO synthase-independent NO production from the nitrate-nitrite-NO pathway.

Automatic calculation of myocardial external efficiency using a single 11C-acetate PET scan.

BACKGROUND: Myocardial external efficiency (MEE) is defined as the ratio of kinetic energy associated with cardiac work [forward cardiac output (FCO)*mean systemic pressure] and the chemical energy from oxygen consumed (MVO2) by the left ventricular mass (LVM). We developed a fully automated method for estimating MEE based on a single 11C-acetate PET scan without ECG-gating. METHODS AND RESULTS: Ten healthy controls, 34 patients with aortic valve stenosis (AVS), and 20 patients with mitral valve regurgitation (MVR) were recruited in a dual-center study. MVO2 was calculated using washout of 11C -acetate activity. FCO and LVM were calculated automatically using dynamic PET and parametric image formation. FCO and LVM were also obtained using cardiac magnetic resonance (CMR) in all subjects. The correlation between MEEPET-CMR and MEEPET was high (r = 0.85, P < 0.001) without significant bias. MEEPET was 23.6 ± 4.2% for controls and was lowered in AVS (17.2 ± 4.3%, P < 0.001) and in MVR (18.0 ± 5.2%, P = 0.004). MEEPET was strongly associated with both NYHA class (P < 0.001) and the magnitude of valvular dysfunction (mean aortic gradient: P < 0.001, regurgitant fraction: P = 0.009). CONCLUSION: A single 11C-acetate PET yields accurate and automated MEE results on different scanners. MEE might provide an unbiased measurement of the phenotypic response to valvular disease.

Global longitudinal strain in long-term risk prediction after acute coronary syndrome: an investigation of added prognostic value to ejection fraction.

AIMS: This study aimed to investigate the additional value of global longitudinal strain (GLS) on top of left ventricular ejection fraction (LVEF) in long-term risk prediction of combined death and heart failure (HF) re-hospitalization after acute coronary syndrome (ACS). METHOD AND RESULTS: This retrospective study included patients admitted with ACS between 2008 and 2014 from the three participating university hospitals. LVEF and GLS were assessed at a core lab from images acquired during the index hospital stay. Their prognostic value was studied with the Cox proportional hazards model (median follow-up 6.2 years). A nested model comparison was performed with C-statistics. A total of 941 patients qualified for multivariable analysis after multiple imputation of missing baseline covariables. The combined outcome was reached in 17.7% of the cases. Both GLS and LVEF were independent predictors of the combined outcome, hazard ratio (HR) 1.068 (95% CI 1.017-1.121) and HR 0.980 (95% CI 0.962-0.998), respectively. The C-statistic increased from 0.742 (95% CI 0.702-0.783) to 0.749 (95% CI 0.709-0.789) (P = 0.693) when GLS entered the model with clinical data and LVEF. CONCLUSION: GLS emerged as an independent long-term risk predictor of all-cause death and HF re-hospitalization. However, there was no significant incremental predictive value of GLS when LVEF was already known.

Medical treatment of heart failure with renin-angiotensin-aldosterone system inhibitors and beta-blockers in aortic stenosis: association with long-term outcome after aortic valve replacement.

Aims: There is a lack of robust data on the optimal medical treatment of heart failure in patients with severe aortic stenosis, with no randomized controlled trials guiding treatment. The study aimed to study the association between exposure to renin-angiotensin-aldosterone system (RAS) inhibitors or beta-blockers and outcome after aortic valve replacement in patients with aortic stenosis and heart failure. Methods and results: The study included all patients with heart failure undergoing aortic valve replacement for aortic stenosis in Sweden between 2008 and 2016 (n = 4668 patients). Exposure to treatment was assessed by a continuous tracking of drug dispensations, and outcome events were all-cause mortality and hospitalization for heart failure collected from national patient registries. After adjustment for age, sex, atrial fibrillation, hypertension, diabetes mellitus, and prior myocardial infarction, Cox regression analysis showed that RAS inhibition was associated with a lower risk of all-cause mortality in patients with reduced left ventricular ejection fraction (LV-EF) [hazard ratio (HR) 0.58, 95% confidence interval (CI) 0.51-0.65] and preserved LV-EF (HR 0.69, 95% CI 0.56-0.85). Beta-blockade was associated with a lower risk of all-cause mortality in patients with reduced LV-EF (HR 0.81, 95% CI 0.71-0.92), but not in preserved LV-EF (HR 0.87, 95% CI 0.69-1.10). There was no association between RAS inhibition or beta-blockade and the risk of hospitalization for heart failure. Conclusion: The RAS inhibition was associated with a lower all-cause mortality after valve replacement in patients with both reduced and preserved LV-EF. Beta-blockade was associated with lower all-cause mortality only in patients with reduced LV-EF.

Associations between inflammatory and angiogenic proteomic biomarkers, and cardiovascular events and mortality in relation to kidney function.

Background: The links between chronic kidney disease (CKD) and the high burden of cardiovascular disease remain unclear. We aimed to explore the association between selected inflammatory and angiogenic biomarkers, kidney function and long-term outcome in patients with an acute coronary syndrome (ACS) and to test the hypothesis that CKD status modifies this association. Methods: A total of 1293 ACS patients hospitalized between 2008 and 2015 were followed until 31 December 2017. Plasma was collected on days 1-3 after admission. A total of 13 biomarkers were a priori identified and analysed with two proteomic methods, proximity extension assay or multiple reaction monitoring mass spectrometry. Boxplots and multiple linear regression models were used to study associations between biomarkers and kidney function and adjusted standardized Cox regression with an interaction term for CKD was used to assess whether CKD modified the association between biomarkers and major adverse cardiovascular events and death (MACE+). Results: The concentrations of nine biomarkers-endothelial cell-specific molecule-1 (ESM-1), fibroblast growth factor 23 (FGF-23), fractalkine (CX3CL1), interleukin-1 receptor antagonist (IL-1RA), interleukin-18 (IL-18), monocyte chemotactic protein-1 (MCP-1), placenta growth factor (PlGF), transmembrane immunoglobulin 1 (TIM-1) and vascular endothelial growth factor A (VEGFA)-were inversely associated with kidney function. ESM-1, FGF-23 and TIM-1 showed associations with MACE+. Only FGF23 remained independently associated after adjustment for the other biomarkers (hazard ratio per standard deviation increase 1.34; 95% Bonferroni corrected confidence interval 1.19-1.50). None of the biomarkers showed an interaction with CKD. Conclusions: The concentrations of 9 of the 13 prespecified inflammatory and angiogenic proteomic biomarkers increased when kidney function declined. Only FGF-23 demonstrated an independent association with MACE+, and this association was not modified by CKD status. These findings further support FGF-23 as an independent prognostic marker in ACS patients with and without CKD.

Quantitation of mitral regurgitation using positron emission tomography.

BACKGROUND: Cardiac positron emission tomography (PET) offers non-invasive assessment of perfusion and left ventricular (LV) function from a single dynamic scan. However, no prior assessment of mitral regurgitation severity by PET has been presented. Application of indicator dilution techniques and gated image analyses to PET data enables calculation of forward stroke volume and total LV stroke volume. We aimed to evaluate a combination of these methods for measurement of regurgitant volume (RegVol) and fraction (RegF) using dynamic 15O-water and 11C-acetate PET in comparison to cardiovascular magnetic resonance (CMR). RESULTS: Twenty-one patients with severe primary mitral valve regurgitation underwent same-day dynamic PET examinations (15O-water and 11C-acetate) and CMR. PET data were reconstructed into dynamic series with short time frames during the first pass, gated 15O-water blood pool images, and gated 11C-acetate myocardial uptake images. PET-based RegVol and RegF correlated strongly with CMR (RegVol: 15O-water r = 0.94, 11C-acetate r = 0.91 and RegF: 15O-water r = 0.88, 11C-acetate r = 0.84, p < 0.001). A systematic underestimation (bias) was found for PET (RegVol: 15O-water - 11 ± 13 mL, p = 0.002, 11C-acetate - 28 ± 16 mL, p < 0.001 and RegF: 15O-water - 4 ± 6%, p = 0.01, 11C-acetate - 10 ± 7%, p < 0.001). PET measurements in patients were compared to healthy volunteers (n = 18). Mean RegVol and RegF was significantly lower in healthy volunteers compared to patients for both tracers. The accuracy of diagnosing moderately elevated regurgitant volume (> 30mL) was 95% for 15O-water and 92% for 11C-acetate. CONCLUSIONS: LV regurgitation severity quantified using cardiac PET correlated with CMR and showed high accuracy for discriminating patients from healthy volunteers.

Impact of clinical diagnosis of myocardial infarction in patients with elevated cardiac troponin.

OBJECTIVE: Type 2 myocardial infarction (MI) and myocardial injury are common conditions associated with an adverse prognosis. Physicians experience uncertainty how to distinguish these conditions, as well as how to manage and treat them. Therefore, the objective of this study was to compare treatment and prognosis in patients with an adjudicated diagnosis of type 2 MI and myocardial injury, who were discharged with and without a clinical diagnosis of MI. DESIGN: The study consisted of two cohorts, 964 and 281 consecutive patients with elevated cardiac troponin, discharged with and without a clinical diagnosis of MI, respectively. All cases were adjudicated into MI type 1-5 or myocardial injury and followed regarding all-cause death. RESULTS: The adjudication identified 138 and 37 cases of type 2 MI, and 86 and 185 of myocardial injury, with and without a clinical MI diagnosis, respectively. In patients with type 2 MI, a clinical MI diagnosis was associated with more coronary angiography investigations (39.1% vs 5.4%, p<0.001) and an increased use of secondary prevention medications (all p<0.001). However, no difference was observed in adjusted 5-year mortality between patients with and without a clinical MI diagnosis (HR: 0.77 with 95% CI 0.43 to 1.38). The results were similar for adjudicated myocardial injury. CONCLUSION: In both type 2 MI and myocardial injury, a clinical diagnosis of MI at discharge was associated with more investigations and treatments. However, no prognostic effect of receiving a clinical MI diagnosis was observed.

The role of imaging in the selection of patients for HFpEF therapy.

Heart failure with preserved ejection fraction (HFpEF) traditionally has been characterized as a form of heart failure without therapeutic options, in particular with a lack of response to the established therapies of heart failure with reduced ejection fraction (HFrEF). However, this is no longer true. Besides physical exercise, risk factor modification, aldosterone blocking agents, and sodium-glucose cotransporter 2 inhibitors, specific therapies are emerging for specific HFpEF etiologies, such as hypertrophic cardiomyopathy or cardiac amyloidosis. This development justifies increased efforts to arrive at specific diagnoses within the umbrella of HFpEF. Cardiac imaging plays by far the largest role in this effort and is discussed in the following review.

Screening for Biomarkers Associated with Left Ventricular Function During Follow-up After Acute Coronary Syndrome.

A proportion of patients with the acute coronary syndrome (ACS) will suffer progressive remodeling of the left ventricular (LV). The aim was to screen for important biomarkers from a large-scale protein profiling in 420 ACS patients and define biomarkers associated with reduced LV function early and 1 year after the ACS. Transferrin receptor protein 1 and NT-proBNP were associated with LV function early and after 1 year, whereas osteopontin and soluble ST2 were associated with LV function in the early phase and, tissue-type plasminogen activator after 1 year. Fatty-acid-binding protein and galectin 3 were related to worse GLS but not to LVEF 1 year after the ACS. Proteins involved in remodeling and iron transport in cardiomyocytes were related to worse LV function after ACS. Biomarkers for energy metabolism and fibrosis were exclusively related to worse LV function by GLS. Studies on the functions of these proteins might add knowledge to the biological processes involved in heart failure in long term after ACS.

Reliability of estimating left ventricular ejection fraction in clinical routine: a validation study of the SWEDEHEART registry.

OBJECTIVE: Patients hospitalized with acute coronary syndrome (ACS) in Sweden routinely undergo an echocardiographic examination with assessment of left ventricular ejection fraction (LVEF). LVEF is a measurement widely used for outcome prediction and treatment guidance. The obtained LVEF is categorized as normal (> 50%) or mildly, moderately, or severely impaired (40-49, 30-39, and < 30%, respectively) and reported to the nationwide registry for ACS (SWEDEHEART). The purpose of this study was to determine the reliability of the reported LVEF values by validating them against an independent re-evaluation of LVEF. METHODS: A random sample of 130 patients from three hospitals were included. LVEF re-evaluation was performed by two independent reviewers using the modified biplane Simpson method and their mean LVEF was compared to the LVEF reported to SWEDEHEART. Agreement between reported and re-evaluated LVEF was assessed using Gwet's AC2 statistics. RESULTS: Analysis showed good agreement between reported and re-evaluated LVEF (AC2: 0.76 [95% CI 0.69-0.84]). The LVEF re-evaluations were in agreement with the registry reported LVEF categorization in 86 (66.0%) of the cases. In 33 (25.4%) of the cases the SWEDEHEART-reported LVEF was lower than re-evaluated LVEF. The opposite relation was found in 11 (8.5%) of the cases (p < 0.005). CONCLUSION: Independent validation of SWEDEHEART-reported LVEF shows an overall good agreement with the re-evaluated LVEF. However, a tendency towards underestimation of LVEF was observed, with the largest discrepancy between re-evaluated LVEF and registry LVEF in subjects with subnormal LV-function in whom the reported assessment of LVEF should be interpreted more cautiously.

Myocardial External Efficiency in Asymptomatic Severe Primary Mitral Regurgitation Using 11C-Acetate PET.

Subjects with asymptomatic moderate-to-severe or severe primary mitral regurgitation are closely observed for signs of progression or symptoms requiring surgical intervention. The role of myocardial metabolic function in progression of mitral regurgitation is poorly understood. We used 11C-acetate PET to noninvasively measure myocardial mechanical external efficiency (MEE), which is the energetic ratio of external cardiac work and left ventricular (LV) oxygen consumption. Methods: Forty-seven patients in surveillance with mitral regurgitation and no or minimal symptoms prospectively underwent PET, echocardiography, and cardiac MRI on the same day. PET was used to simultaneously measure cardiac output, LV mass, and oxygen consumption to establish MEE. PET findings were compared between patients and healthy volunteers (n = 9). MEE and standard imaging indicators of regurgitation severity, LV volumes, and function were studied as predictors of time to surgical intervention. Patients were followed a median of 3.0 y (interquartile range, 2.0-3.8 y), and the endpoint was reached in 22 subjects (47%). Results: MEE in patients reaching the endpoint (23.8% ± 5.0%) was lower than in censored patients (28.5% ± 4.5%, P = 0.002) or healthy volunteers (30.1% ± 4.9%, P = 0.001). MEE with a cutoff lower than 25.7% was significantly associated with the outcome (hazard ratio, 7.5; 95% CI, 2.7-20.6; P < 0.0001) and retained independent significance when compared with standard imaging parameters. Conclusion: MEE independently predicted time to progression requiring valve surgery in patients with asymptomatic moderate-to-severe or severe primary mitral regurgitation. The study suggests that inefficient myocardial oxidative metabolism precedes clinically observed progression in mitral regurgitation.

Prognostic importance of biomarkers associated with haemostatic, vascular and endothelial disturbances in acute coronary syndrome patients in relation to kidney function.

BACKGROUND: Patients with kidney failure have a high risk for cardiovascular events. We aimed to evaluate the prognostic importance of selected biomarkers related to haemostasis, endothelial function, and vascular regulation in patients with acute coronary syndrome (ACS), and to study whether this association differed in patients with renal dysfunction. METHODS: Plasma was collected in 1370 ACS patients included between 2008 and 2015. Biomarkers were analysed using a Proximity Extension Assay and a Multiple Reaction Monitoring mass spectrometry assay. To reduce multiplicity, biomarkers correlating with eGFR were selected a priori among 36 plasma biomarkers reflecting endothelial and vascular function, and haemostasis. Adjusted Cox regression were used to study their association with the composite outcome of myocardial infarction, ischemic stroke, heart failure or death. Interaction with eGFR strata above or below 60 ml/min/1.73 m2 was tested. RESULTS: Tissue factor, proteinase-activated receptor, soluble urokinase plasminogen activator surface receptor (suPAR), thrombomodulin, adrenomedullin, renin, and angiotensinogen correlated inversely with eGFR and were selected for the Cox regression. Mean follow-up was 5.2 years during which 428 events occurred. Adrenomedullin, suPAR, and renin were independently associated with the composite outcome. Adrenomedullin showed interaction with eGFR strata (p = 0.010) and was associated with increased risk (HR 1.88; CI 1.44-2.45) only in patients with eGFR ≥60 ml/min/ 1.73 m2. CONCLUSIONS: Adrenomedullin, suPAR, and renin were associated with the composite outcome in all. Adrenomedullin, involved in endothelial protection, showed a significant interaction with renal function and outcome, and was associated with the composite outcome only in patients with preserved kidney function.

The Role of Novel Cardiac Imaging for Contemporary Management of Heart Failure.

Heart failure is becoming the central problem in cardiology. Its recognition, differential diagnosis, and the monitoring of therapy are intimately coupled with cardiac imaging. Cardiac imaging has witnessed an explosive growth and differentiation, with echocardiography continuing as the first diagnostic step; the echocardiographic exam itself has become considerably more complex than in the last century, with the assessment of diastolic left ventricular function and strain imaging contributing important information, especially in heart failure. Very often, however, echocardiography can only describe the fact of functional impairment and morphologic remodeling, whereas further clarification of the underlying disease, such as cardiomyopathy, myocarditis, storage diseases, sarcoidosis, and others, remains elusive. Here, cardiovascular magnetic resonance and perfusion imaging should be used judiciously to arrive as often as possible at a clear diagnosis which ideally enables specific therapy.