Third universal definition of myocardial infarction

A sensitive and specific quantitation method for determination of serum cardiac myosin binding protein-C by electrochemiluminescence immunoassay

Biomarkers are becoming increasingly more important in clinical decision-making, as well as basic science. Diagnosing myocardial infarction (MI) is largely driven by detecting cardiac-specific proteins in patients' serum or plasma as an indicator of myocardial injury. Having recently shown that cardiac myosin binding protein-C (cMyBP-C) is detectable in the serum after MI, we have proposed it as a potential biomarker for MI. Biomarkers are typically detected by traditional sandwich enzyme-linked immunosorbent assays. However, this technique requires a large sample volume, has a small dynamic range, and can measure only one protein at a time. Here we show a multiplex immunoassay in which three cardiac proteins can be measured simultaneously with high sensitivity. Measuring cMyBP-C in uniplex or together with creatine kinase MB and cardiac troponin I showed comparable sensitivity. This technique uses the Meso Scale Discovery (MSD) method of multiplexing in a 96-well plate combined with electrochemiluminescence for detection. While only small sample volumes are required, high sensitivity and a large dynamic range are achieved. Using this technique, we measured cMyBP-C, creatine kinase MB, and cardiac troponin I levels in serum samples from 16 subjects with MI and compared the results with 16 control subjects. We were able to detect all three markers in these samples and found all three biomarkers to be increased after MI. This technique is, therefore, suitable for the sensitive detection of cardiac biomarkers in serum samples.

Diagnosis of MI after CABG with high-sensitivity troponin T and new ECG or echocardiogram changes: relationship with mortality and validation of the universal definition of MI

AIMS

Criteria for diagnosing myocardial infarction (MI) after coronary artery bypass grafting (CABG) are controversial. Uncertainties remain around the optimal threshold for biomarker elevation and the need for associated criteria. There are no studies of high-sensitivity troponin (hs-TnT) after CABG. We assessed whether using hs-TnT to define MI after CABG was associated with 30-day and medium-term mortality and evaluated the utility of adding to the troponin criteria new Q-waves or imaging evidence of new wall motion abnormality as suggested in the Universal Definition of MI.

METHODS

Isolated CABG was performed in 818 patients from July 2010 to June 2012 and hs-TnT was measured 12-24 hours after CABG. Patients with rising baseline or missing troponins (n=258) were excluded. Thresholds of 140 ng/l (10-times 99th percentile upper reference limit) and 500 ng/l (10-times coefficient of variation of 10% for fourth-generation troponin T applied to hs-TnT) were prespecified.

RESULTS

Mean follow up was 1.8±0.6 years. On multivariate analyses, isolated hs-TnT rise >140 ng/l (n=360) or >500 ng/l (n=162) were not associated with mortality. Additional ECG and/or echocardiographic criteria plus hs-TnT >140 ng/l was associated with 30-day mortality (hazard ratio, HR, 4.92, 95% CI 1.34-18.1; p=0.017) and medium-term mortality (HR 3.44, 95% CI 1.13-10.5; p=0.030), whereas ECG and/or echocardiographic abnormalities with hs-TnT >500 ng/l was not (p=0.281 and p=0.123 for 30-day and medium-term mortality, respectively).

CONCLUSIONS

A definition for MI following CABG using hs-TnT with a cut point of 10-times 99th percentile upper reference limit and ECG and/or echocardiographic criteria predicts 30-day and medium-term mortality. These findings validate the Third Universal Definition of type 5 MI.

Predictive factors of late venous aortocoronary graft failure: ultrastructural studies

Background

Venous aortocoronary graft arterialization may precede a preterm occlusion in some coronary artery bypass grafting (CABG) patients. The aim of the present study was to identify ultrastructural variations in the saphenous vein wall that may have an impact on the development of venous graft disease in CABG patients.

Methods

The study involved 365 consecutive patients with a mean age of 62.9±9.4 years who underwent isolated CABG. The thickness and area of the whole venous wall, the tunica intima, the tunica media and the adventitia and the number and shape (length, thickness and length/thickness ratio) of the nuclei in the medial smooth muscle cells nuclei in the distal saphenous vein segments were evaluated by ultrastructural studies. Patients were followed up for 41 to 50 months (mean 45.1±5.1). Saphenous vein graft patency was assessed by follow-up coronary angiography. Logistic regression models were used to identify independent risk factors for late graft failure.

Results

In 71 patients significant lesions in the saphenous vein grafts were observed. The whole venous wall thickness (437.5 µm vs. 405.5 µm), tunica media thickness (257.2 µm vs. 211.5 µm), whole venous wall area (2.23 mm² vs. 2.02 mm²) and tunica media area (1.09 mm² vs. 0.93 mm²) were significantly larger for this group of patients than for those without graft disease. In the latter group more elongated smooth muscle cell nuclei (higher length/thickness ratio) were found in the tunica media of the saphenous vein segments. Thickening of the saphenous vein tunica media and chunky smooth muscle cell nuclei were identified as independent risk factors for graft disease development.

Conclusions

Saphenous vein tunica media hypertrophy (resulting in wall thickening) and chunky smooth muscle cell nuclei might predict the development of venous graft disease.

Circulating microRNAs as novel biomarkers for the early diagnosis of acute coronary syndrome

Small non-coding microRNAs (miRNAs) are important physiological regulators of post-transcriptional gene expression. miRNAs not only reside in the cytoplasm but are also stably present in several extracellular compartments, including the circulation. For that reason, miRNAs are proposed as diagnostic biomarkers for various diseases. Early diagnosis of acute coronary syndrome (ACS), especially non-ST elevated myocardial infarction and unstable angina pectoris, is essential for optimal treatment outcome, and due to the ongoing need for additional identifiers, miRNAs are of special interest as biomarkers for ACS. This review highlights the nature and cellular release mechanisms of circulating miRNAs and therefore their potential role in the diagnosis of myocardial infarction. We will give an update of clinical studies addressing the role of circulating miRNA expression after myocardial infarction and explore the diagnostic value of this potential biomarker.

Survival after hospital discharge for ST-segment elevation and non-ST-segment elevation acute myocardial infarction: a population-based study

Background

Limited recent data are available describing differences in long-term survival, and factors affecting prognosis, after ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI), especially from the more generalizable perspective of a population-based investigation. The objectives of this study were to examine differences in post-discharge prognosis after hospitalization for STEMI and NSTEMI, with a particular focus on factors associated with reduced long-term survival.

Methods

We reviewed the medical records of residents of the Worcester, MA, USA metropolitan area hospitalized at eleven central Massachusetts medical centers for acute myocardial infarction (AMI) during 2001, 2003, 2005, and 2007.

Results

A total of 3762 persons were hospitalized with confirmed AMI; of these, 2539 patients (67.5%) were diagnosed with NSTEMI. The average age of study patients was 70.3 years and 42.9% were women. Patients with NSTEMI experienced higher post-discharge death rates with 3-month, 1-year, and 2-year death rates of 12.6%, 23.5%, and 33.2%, respectively, compared to 6.1%, 11.5%, and 16.4% for patients with STEMI. After multivariable adjustment, patients with NSTEMI were significantly more likely to have died after hospital discharge (adjusted hazards ratio 1.28; 95% confidence interval 1.14–1.44). Several demographic (eg, older age) and clinical (eg, history of stroke) factors were associated with reduced long-term survival in patients with NSTEMI and STEMI.

Conclusions

The results of this study in residents of central Massachusetts suggest that patients with NSTEMI are at higher risk for dying after hospital discharge, and several subgroups are at particularly increased risk.

Potential biomarkers for predicting outcomes in CABG cardiothoracic surgeries

The variations in recovery time, complications, and survival among cardiac patients who have undergone coronary artery bypass graft (CABG) procedures are vast. Many formulas and theories are used to predict clinical outcome and recovery time, and current prognostic predictions are based on medical and family history, lifestyle, co-morbidities, and performance status. The identification of biomarkers that provide concrete evidence supporting clinical outcome has greatly affected the field of medicine, helping clinicians in many medicine sub-specialties to forecast clinical course. Recent studies have discovered biomarkers that may be used as predictors of cardiac patients' status post-cardiothoracic surgery, and the applications are numerous. In this review, we assess currently available cardiac biomarkers as predictors of clinical outcome for post-operative CABG patients. Data were collected from various studies in which cardiac biomarkers were measured in pre-operative and post-operative CABG patients.

Usefulness of Q-wave area for threshold-based stratification of global left ventricular myocardial infarct size

Left ventricular (LV) infarct size affects prognosis after acute myocardial infarction (AMI). Delayed enhancement cardiac magnetic resonance (DE-CMR) provides accurate infarct quantification but is unavailable or contraindicated in many patients. This study tested whether simple electrocardiography (ECG) parameters can stratify LV infarct size. One hundred fifty-two patients with AMI underwent DE-CMR and serial 12-lead ECG. Electrocardiograms were quantitatively analyzed for multiple aspects of Q-wave morphology, including duration, amplitude, and geometric area (QWAr) summed across all leads except aVR. Patients with pathologic Q waves had larger infarcts measured by DE-CMR or enzymes (both p <0.001), even after controlling for infarct distribution by CMR or x-ray angiography. Comparison between early (4 ± 0.4 days after AMI) and follow-up (29 ± 6 days) ECG demonstrated temporal reductions in Q-wave amplitude (1.8 ± 1.4 vs 1.6 ± 1.6 mV; p = 0.03) but not QWAr (41 ± 38 vs 39 ± 43 mV•ms; p = 0.29). At both times, QWAr augmented stepwise with DE-CMR quantified infarct size (p <0.001). QWAr increased markedly at 10% LV infarct threshold, with differences more than threefold on early ECG (59 ± 39 vs 18 ± 20 mV•ms; p <0.001) and nearly fivefold (59 ± 46 vs 13 ± 16 mV•ms; p <0.001) on follow-up. Diagnostic performance compared with a 10% infarction cutoff was good on early (area under the curve = 0.84) and follow-up (area under the curve = 0.87) ECG. Optimization of sensitivity (95% to 98%) enabled QWAr to exclude affected patients with 90% to 94% negative predictive value at each time point. In conclusion, LV infarct size is accompanied by stepwise increments in Q-wave morphology, with QWAr increased three- to fivefold at a threshold of 10% LV infarction. Stratification based on QWAr provides excellent negative predictive value for exclusion of large (≥10%) LV infarct burden.

Remote ischaemic postconditioning: does it protect against ischaemic damage in percutaneous coronary revascularisation? Randomised placebo-controlled clinical trial

OBJECTIVE

Determine whether remote ischaemic postconditioning (RIP) protects against percutaneous coronary intervention-related myocardial infarction (PCI-MI).

DESIGN

Single-centre, randomised, blinded to the researchers, clinical trial. ClinicalTrials.gov (NCT 01113008).

SETTING

Tertiary hospital centre.

PATIENTS

232 patients underwent elective PCI for stable or unstable angina.

INTERVENTIONS

Patients were randomised to RIP (induction of three 5-min cycles of ischaemia in the arm after the PCI) versus placebo.

MAIN OUTCOME MEASURES

The primary outcome measure was the peak 24-h troponin I level. PCI-MI was defined by an elevation of troponin values >3 or >5 of the 99th percentile according to the classical or the new definition. The secondary outcome measure was hospital admission, PCI for stable angina or acute coronary syndrome and mortality after 1 year of follow-up. The use of RIP in diabetic patients was specifically studied.

RESULTS

The mean age was 64.6 years, and 42% were diabetic. The peak troponin in the RIP patients was 0.476 vs 0.478 ng/mL (p=0.99). PCI-MI occurred in 36% of the RIP patients versus 30.8% in the placebo group (p=0.378). Diabetic RIP patients had more PCI-MI (new definition): OR 2.7; 95% CI 1.10 to 6.92; p=0.027. The secondary outcome measure was seen in 11.7% of the RIP patients versus 10.8% in the placebo group (p=0.907).

CONCLUSIONS

RIP did not reduce the damage associated with elective PCI or cardiovascular events during the follow-up. The diabetic population who underwent RIP had more PCI-MI.

Troponin T in acute ischemic stroke

Multiple interactions are considered to occur among the various forms of cardiovascular and cerebrovascular diseases. The aim of this study was to assess the serum level profile of cardiac troponin T (cTnT) in patients with acute ischemic stroke (AIS) to evaluate factors associated with increased serum levels of cTnT. Patients with AIS enrolled in this prospective observational study were admitted to the hospital <12 hours after stroke onset. At admission, and 4 hours later, all patients were subjected to neurologic examinations and brain computed tomography or magnetic resonance imaging; standard laboratory tests, including cTnT and other cardiac markers; and repeated electrocardiography. Correlations between cTnT and several baseline parameters were tested, and multivariate regression analysis was used to assess the predictors of cTnT elevation. In total, 107 consecutive patients with AIS (65 men, mean age 67.2 ± 14.2 years) were enrolled. Thirty-nine patients (36.4%) presented with elevated cTnT above the upper limit of normal. The cTnT levels were correlated significantly with age (r = 0.448) and the levels of N-terminal pro-brain natriuretic peptide (r = 0.528), cystatin C (r = 0.457), creatine kinase-MB mass (r = 0.253), urea (r = 0.281), and albumin (r = -0.219). Multiple logistic regression analysis found creatinine >90 μmol/L (odds ratio 3.45, 95% confidence interval 1.09 to 10.85), N-terminal pro-brain natriuretic peptide (odds ratio 100 μg/L increase 1.09, 95% confidence interval 1.03 to 1.16), and creatine kinase-MB mass (odds ratio per 1 μg/L increase 1.45, 95% confidence interval 1.04 to 2.04) were associated with cTnT elevation in patients with AIS. In conclusion, elevated cTnT can be frequently detected in patients with AIS. To reliably identify patients with current acute myocardial impairment, more in-depth clinical investigation is needed.

Clinical outcome endpoints in heart failure trials: a European Society of Cardiology Heart Failure Association consensus document

Endpoint selection is a critically important step in clinical trial design. It poses major challenges for investigators, regulators, and study sponsors, and it also has important clinical and practical implications for physicians and patients. Clinical outcomes of interest in heart failure trials include all-cause mortality, cause-specific mortality, relevant non-fatal morbidity (e.g., all-cause and cause-specific hospitalization), composites capturing both morbidity and mortality, safety, symptoms, functional capacity, and patient-reported outcomes. Each of these endpoints has strengths and weaknesses that create controversies regarding which is most appropriate in terms of clinical importance, sensitivity, reliability, and consistency. Not surprisingly, a lack of consensus exists within the scientific community regarding the optimal endpoint(s) for both acute and chronic heart failure trials. In an effort to address these issues, the Heart Failure Association of the European Society of Cardiology (HFA-ESC) convened a group of expert heart failure clinical investigators, biostatisticians, regulators, and pharmaceutical industry scientists (Nice, France, 12-13 February 2012) to evaluate the challenges of defining heart failure endpoints in clinical trials and to develop a consensus framework. This report summarizes the group's recommendations for achieving common views on heart failure endpoints in clinical trials.

Impact of anticoagulation on coronary flow in patients with non-ST elevation acute coronary syndrome

The effect of anticoagulation by heparin on patients with non-ST elevation acute coronary syndrome (NSTE-ACS), receiving early dual antiplatelet therapy, has not been fully evaluated. We classified 355 patients with NSTE-ACS according to the adequacy of anticoagulation (percentage of low activated partial thromboplastin time [APTT] level). The 6-hour APTT level was optimal in only 23.1% of the patients treated with unfractionated heparin. The rate of poor preprocedural coronary blood flow (thrombolysis in myocardial infarction grade <3, 39.1%, 30.5%, 30.3%, and 33.9% in the 100% low-, 99%∼50% low-, 49%∼1% low-, and 0% low-APTT group, respectively, P = .632) and bleeding events did not differ between the groups. Instead, in multivariate analysis, the diagnosis of myocardial infarction was the only independent predictor of poor coronary flow. For bleeding events, the usage of glycoprotein IIb/IIIa inhibitor appeared to be a sole risk factor. In conclusion, inadequate preprocedural anticoagulation was not associated with adverse outcomes in patients with NSTE-ACS treated with dual antiplatelet agents.

Implications of changing definitions of myocardial infarction on number of events and all-cause mortality: the WHO 1979, ESC/ACC 2000, AHA 2003, and Universal 2007 definitions revisited

PURPOSE

To analyse the impact of four different definitions of acute myocardial infarction (AMI) on number of events and all-cause mortality after AMI.

METHODS

We retrospectively examined number of AMI events and mortality according to four different definitions of AMI, among 1494 patients admitted to Haukeland University Hospital in Norway from March 2002 to February 2003. Eligible for analysis were 815 patients with a discharge diagnosis of an AMI, and 679 patients without any AMI discharge diagnosis but with elevated cardiac troponin I level during admission.

RESULTS

Applying the WHO 1979 definition resulted in 566 definite AMIs among the 1494 patients and was used as reference. According to the other definitions, there were 455 (-20%) definite AMIs by the original troponin 'rise and fall' version of the ESC/ACC 2000 definition, 729 (+29%) by the troponin 'rise or fall' interpretation of the ESC/ACC 2000 definition, 761 (+34%) by the AHA 2003 definition, and 743 (+31%) by the Universal 2007 definition (all p < 0.001). The 28-day, 1-year, 5-year, and 8-year mortality for definite AMI applying the WHO 1979 definition was 12, 19, 32, and 40%, whereas applying the Universal 2007 definition resulted in a mortality of 14, 21, 35, and 43%, respectively.

CONCLUSIONS

The change of definitions of AMI during the last decades has had a significant impact on the number of AMI events and a moderate impact on the AMI mortality among hospitalized patients.

Toxic cardiomyopathy leading to fatal acute cardiac failure related to vandetanib: a case report with histopathological analysis

CONTEXT

Medullary thyroid carcinoma (MTC) accounts for 3-4% of all malignant thyroid neoplasias. Vandetanib, a tyrosine kinase inhibitor (TKI) targeting vascular endothelial growth factor receptor 2, epidermal growth factor receptor, and RET, has been approved by the FDA for the treatment of locally advanced or metastatic MTC. The heart seems to be particularly susceptible to adverse effects associated with TKI therapy, and virtually all TKIs have been associated with cardiovascular events.

CLINICAL PRESENTATION

We report the case of a patient with metastatic MTC who was enrolled in the Phase III clinical study (NCT00410761) and presented a favorable response to vandetanib therapy, displaying marked decrease in the level of serologic tumor markers and shrinkage of metastatic lesions. After 14 months of therapy, the patient developed a fatal cardiac failure. Myocardial infarction was excluded by serial measurements of specific cardiac markers (serial troponin-T measurements varied from 0.037 to 0.042 ng/ml) and serologic tests for Chaga's disease were negative. Postmortem examination of the heart revealed cardiomyocyte hypertrophy and marked myocyte degeneration in the subendocardial zones and papillary muscles of the myocardium. These pathological changes are similar to those observed in TKI-treated rats and are suggestive of drug-induced cardiotoxicity.

CONCLUSION

This case illustrates a previously unreported serious vandetanib-related adverse effect and highlights the need for close monitoring of patients under TKI therapy in order to identify early signs of congestive heart failure or myocardium damage.

Combined delivery of bone marrow-derived mononuclear cells in chronic ischemic heart disease: rationale and study design

BACKGROUND

Treatment with bone marrow-derived mononuclear cells (BM-MNC) may improve left ventricular (LV) function in patients with chronic ischemic heart disease (IHD). Delivery method of the cell product may be crucial for efficacy.

HYPOTHESIS

We aimed to demonstrate that the combination of intramyocardial and intracoronary injection of BM-MNC is safe and improves LV function in patients with chronic IHD.

METHODS

After a safety/feasibility phase of 10 patients, 54 patients will be randomly assigned in a 1:1:1 pattern to 1 control and 2 BM-MNC treatment groups. The control group will be treated with state-of-the-art medical management. The treatment groups will receive either exclusively intramyocardial injection or a combination of intramyocardial and intracoronary injection of autologous BM-MNC. Left ventricular function as well as scar size, transmural extension, and regional wall-motion score will be assessed by cardiac magnetic resonance imaging studies at baseline and after 6 months. The primary endpoint is the change in global LV ejection fraction by cardiac magnetic resonance from 6 months to baseline.

RESULTS

The results, it is hoped, will have important clinical impact and provide essential information to improve the design of future regenerative-medicine protocols in cardiology.

CONCLUSIONS

As cell delivery may play an important role in chronic IHD, we aim to demonstrate feasibility and efficacy of a combined cell-delivery approach in patients with decreased LV function.

Update on the Universal Definition of Acute Myocardial Infarction in the Light of New Data

At the 2012 European Society of Cardiology (ESC) Conference in Munich, the updated Universal Definition of myocardial infarction was presented for the first time and was then published simultaneously in five medical journals (European Heart Journal, Circulation, Journal of American College of Cardiology, Nature Reviews Cardiology, Global Heart). Major changes in this updated version include the differentiation between myocardial ischemia and myocardial injury, which gives credit to the relatively large number of patients with troponin positive test results, especially when measured with high sensitivity assays, in patients without myocardial ischemia. Another important topic is the revised criteria for the diagnoses of acute myocardial ischemia related to percutaneous coronary intervention (PCI) and coronary arterial bypass grafting (CABG).

Early diastolic strain rate in relation to systolic and diastolic function and prognosis in acute myocardial infarction: a two-dimensional speckle-tracking study

AIMS

Diastolic dysfunction in acute myocardial infarction (MI) is associated with adverse outcome. Recently, the ratio of early mitral inflow velocity (E) to global diastolic strain rate (e'sr) has been proposed as a marker of elevated LV filling pressure. However, the prognostic value of this measure has not been demonstrated in a large-scale setting when existing parameters of diastolic function are known. We hypothesized that the E/e'sr ratio would be independently associated with an adverse outcome in patients with MI.

METHODS AND RESULTS

We prospectively included patients with MI and performed echocardiography with comprehensive diastolic evaluation including E/e'sr. The relationship between E/e'sr and the primary composite endpoint (all-cause mortality, hospitalization for heart failure (HF), stroke, and new onset atrial fibrillation) was analysed with Cox models. A total of 1048 patients (mean age 63 ± 12, 73% male) were included and 142 patients (13.5%) reached the primary endpoint (median follow-up 29 months). A significant prognostic value was found for E/e'sr [hazard ratio (HR) per 1 unit change: 2.36, 95% confidence interval (CI): 2.02-2.75, P < 0.0001]. After multivariable adjustment E/e'sr remained independently related to the combined endpoint (HR per 1 unit change, 1.50; CI: 1.05-2.13, P = 0.02). The prognostic value of E/e'sr was driven by mortality (HR per 1 unit change, 2.52; CI: 2.09-3.04, P < 0.0001) and HF admissions (HR per 1 unit change, 2.79; CI: 2.23-3.48, P < 0.0001).

CONCLUSION

Deformation-based E/e'sr contributes important information about global myocardial relaxation superior to velocity-based analysis and is independently associated with the outcome in acute MI.

Completeness and diagnostic validity of recording acute myocardial infarction events in primary care, hospital care, disease registry, and national mortality records: cohort study

OBJECTIVE

To determine the completeness and diagnostic validity of myocardial infarction recording across four national health record sources in primary care, hospital care, a disease registry, and mortality register.

DESIGN

Cohort study.

PARTICIPANTS

21 482 patients with acute myocardial infarction in England between January 2003 and March 2009, identified in four prospectively collected, linked electronic health record sources: Clinical Practice Research Datalink (primary care data), Hospital Episode Statistics (hospital admissions), the disease registry MINAP (Myocardial Ischaemia National Audit Project), and the Office for National Statistics mortality register (cause specific mortality data).

SETTING

One country (England) with one health system (the National Health Service).

MAIN OUTCOME MEASURES

Recording of acute myocardial infarction, incidence, all cause mortality within one year of acute myocardial infarction, and diagnostic validity of acute myocardial infarction compared with electrocardiographic and troponin findings in the disease registry (gold standard).

RESULTS

Risk factors and non-cardiovascular coexisting conditions were similar across patients identified in primary care, hospital admission, and registry sources. Immediate all cause mortality was highest among patients with acute myocardial infarction recorded in primary care, which (unlike hospital admission and disease registry sources) included patients who did not reach hospital, but at one year mortality rates in cohorts from each source were similar. 5561 (31.0%) patients with non-fatal acute myocardial infarction were recorded in all three sources and 11 482 (63.9%) in at least two sources. The crude incidence of acute myocardial infarction was underestimated by 25-50% using one source compared with using all three sources. Compared with acute myocardial infarction defined in the disease registry, the positive predictive value of acute myocardial infarction recorded in primary care was 92.2% (95% confidence interval 91.6% to 92.8%) and in hospital admissions was 91.5% (90.8% to 92.1%).

CONCLUSION

Each data source missed a substantial proportion (25-50%) of myocardial infarction events. Failure to use linked electronic health records from primary care, hospital care, disease registry, and death certificates may lead to biased estimates of the incidence and outcome of myocardial infarction.

TRIAL REGISTRATION

NCT01569139 clinicaltrials.gov.

Impact of intraoperative hyperglycaemia on renal dysfunction after off-pump coronary artery bypass

OBJECTIVES

Acute kidney injury (AKI) is one of the most frequently occurring complications after off-pump coronary artery bypass graft (OPCAB). Hyperglycaemia is a major, potentially modifiable risk factor of adverse outcome after cardiac surgery known to aggravate organ damage. The aim of this study was to address the association between intraoperative glucose concentration and postoperative AKI in patients who underwent OPCAB.

METHODS

The medical records of 880 consecutive patients were retrospectively reviewed. Patients were divided into three groups according to the time-weighted average of intraoperative glucose concentrations (<110, 110-150 and >150 mg/dl), and the incidence of AKI (increase of serum creatinine to >2.0 mg/dl and 2 × most recent preoperative value or a new requirement for dialysis) was compared. Multivariate logistic regression analysis was performed to identify independent risk factors for postoperative AKI.

RESULTS

The incidence of AKI was higher in patients with a glucose level >150 mg/dl than in patients with a glucose level = 110-150 mg/dl [8% (20 of 251) vs 3% (14 of 453), P = 0.004]. On multivariate analysis, glucose >150 mg/dl (odds ratio [OR], 2.78; 95% confidence interval [CI], 1.12-6.86, P = 0.027), coefficient of variation of glucose (OR, 1.04; 95% CI, 1.01-1.07, P = 0.027) and preoperative serum creatinine >1.4 mg/dl (OR, 8.81; 95% CI, 3.90-19.9, P < 0.001) were identified as independent risk factors for postoperative AKI.

CONCLUSIONS

Intraoperative glucose concentration >150 mg/dl and increased variability of glucose were independently associated with AKI after OPCAB. Tight intraoperative glycaemic control (<110 mg/dl) does not seem to provide additional benefit in terms of AKI.

Immunohistochemical detection of S100A1 in the postmortem diagnosis of acute myocardial infarction

Background

Sudden cardiac death resulting from acute myocardial infarction (AMI) constitutes a significant percentage of the caseload for forensic and clinical pathologists. When sudden death occurs at an early stage (<6 h), pathologists experience difficulty in the postmortem diagnosis of AMI. Because of the specific tissue distribution of S100A1 and its relationship with acute ischemic heart disease, this study aimed to evaluate the performance of S100A1 in the postmortem diagnosis of AMI.

Methods

We constructed a rat model of AMI through permanent ligation of the left anterior descending coronary artery (LAD) to investigate the depletion of S100A1 from ischemic cardiomyocytes by immunohistochemistry and measuring S100A1 plasma concentrations by enzyme-linked immunosorbent assay at varying post-infarction intervals. In addition, immunohistochemical staining of S100A1 for definite infarction, suspected early infarction, and in normal human hearts, was also performed to test its practical feasibility for postmortem diagnosis of AMI at an early stage.

Results

As early as 15 min after ligation of the LAD, depletion of S100A1 was observed in ischemic cardiomyocytes, and S100A1 plasma concentration was also significantly higher than that of the sham-operated group (P < 0.001). With continuation of the occlusion time, the depleted areas of S100A1 further expanded and S100A1 plasma concentrations further increased. For autopsy material, all human cases of definite myocardial infarction and suspected early infarction showed well-defined areas without S100A1 staining. None of the normal human cases showed diffuse depletion of S100A1.

Conclusion

Our results suggest that immunohistochemical detection of S100A1 is useful for the postmortem diagnosis of AMI at an early stage.

Virtual slides

The virtual slide(s) for this article can be found here:

http://www.diagnosticpathology.diagnomx.eu/vs/4366650979519818

Discordances in the application of different criteria for quantification of paediatric abdominal obesity: an analysis of two Swiss studies

Several definitions of paediatric abdominal obesity have been proposed but it is unclear whether they lead to similar results. We assessed the prevalence of abdominal obesity using five different waist circumference-based definitions and their agreement with total body fat (TBF) and abdominal fat (AF). Data from 190 girls and 162 boys (Ballabeina), and from 134 girls and 113 boys (Kinder-Sportstudie, KISS) aged 5–11 years were used. TBF was assessed by bioimpedance (Ballabeina) or dual energy X-ray absorption (KISS). On the basis of the definition used, the prevalence of abdominal obesity varied between 3.1 and 49.4% in boys, and 4.7 and 55.5% in girls (Ballabeina), and between 1.8 and 36.3% in boys and 4.5 and 37.3% in girls (KISS). Among children considered as abdominally obese by at least one definition, 32.0 (Ballabeina) and 44.7% (KISS) were considered as such by at least two (out of five possible) definitions. Using excess TBF or AF as reference, the areas under the receiver operating curve varied between 0.577 and 0.762 (Ballabeina), and 0.583 and 0.818 (KISS). We conclude that current definitions of abdominal obesity in children lead to wide prevalence estimates and should not be used until a standard definition can be proposed.

Sensitive troponin assays and N-terminal pro-B-type natriuretic peptide in acute coronary syndrome: prediction of significant coronary lesions and long-term prognosis

BACKGROUND

Sensitive troponin assays have substantially improved early diagnosis of myocardial infarction. However, the role of sensitive cardiac troponin (cTn) assays in prediction of significant coronary lesions and long-term prognosis in non-ST-elevation acute coronary syndrome (NSTE-ACS) remains unresolved.

METHODS

This prospective study includes 458 consecutive patients with NSTE-ACS admitted for coronary angiography. Serum levels of 4 commercial available sensitive troponin assays were analyzed (Roche high-sensitive cTnT [hs-cTnT; Roche Diagnostics, Basel, Switzerland], Siemens cTnI Ultra [Siemens, Munich, Germany], Abbott-Architect cTnI [Abbott, Abbott Park, IL], Access Accu-cTnI [Beckman Coulter, Nyon, Switzerland]), as well as a standard assay (Roche cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), before coronary angiography.

RESULTS

The relationship between the analyzed biomarkers and significant coronary lesions on coronary angiography, as quantified by area under the receiver operating characteristic curve, was significantly higher with Roche hs-cTnT, Siemens cTnI Ultra, and Access Accu-cTnI as compared with standard troponin T assay (P < .001 for all comparisons). This difference was mainly caused by increased sensitivity below the 99th percentile. Also, NT-proBNP was associated with the presence of significant coronary lesions. Cardiac troponin values were correlated with cardiac death (primary end point) during 1373 (1257-1478) days of follow-up. In both univariate and multivariate Cox regression analyses, NT-proBNP was superior to both hs-cTnT and cTnI in prediction of cardiovascular mortality. Troponin values with all assays were correlated with the need for repeated revascularization (secondary end point) during follow-up.

CONCLUSIONS

Sensitive cTn assays are superior to standard cTnT assay in prediction of significant coronary lesions in patients with NSTE-ACS. However, this improvement is primary caused by increased sensitivity below the 99th percentile. N-terminal pro-B-type natriuretic peptide is superior to cTns in prediction of long-term mortality.

Rationale and design of the LEADERS FREE trial: A randomized double-blind comparison of the BioFreedom drug-coated stent vs the Gazelle bare metal stent in patients at high bleeding risk using a short (1 month) course of dual antiplatelet therapy

BACKGROUND AND RATIONALE

Major bleeding is a powerful predictor of morbidity and mortality after percutaneous coronary intervention (PCI). To avoid prolonged dual antiplatelet therapy (DAPT), current guidelines recommend using a bare metal stent when PCI is indicated to treat patients at high risk of bleeding. The Biolimus A9-coated BioFreedom is a new stainless steel drug-coated stent devoid of polymer and has been shown to be associated with a low median late-loss of 0.17 mm at 12 months of follow-up. In an animal model, 98% of the drug has diffused into the vessel wall at 1 month. It is therefore reasonable to consider that such a device may have a potential safety advantage, and a lesser dependence on prolonged DAPT than a polymer-coated drug-eluting stent.

TRIAL DESIGN

A total of 2456 patients considered at high risk of bleeding will be randomized in a double-blind fashion to the BioFreedom drug-coated stent or to a control arm (Gazelle bare metal stent). Both groups will be treated with DAPT during 1 month only, followed by long-term aspirin alone. At 1-year follow-up, the primary safety endpoint (a composite of cardiac death, myocardial infarction and stent thrombosis) will be assessed by a non-inferiority analysis, and the primary efficacy endpoint (clinically driven target lesion revascularization) by a superiority analysis.

CONCLUSIONS

This trial should help better characterize a neglected subset of PCI patients and quantify both their thrombotic and bleeding risks. It has the potential to decrease the need for target lesion revascularization in patients unable to tolerate a prolonged course of DAPT and will assess the shortest DAPT course ever used with an active stent.

Cardiac MRI of acute coronary syndrome

Acute coronary syndrome (ACS) is a major cause of morbidity and mortality worldwide. New serological biomarkers, such as troponins, have improved the diagnosis of ACS; however, the diagnosis of ACS can still be difficult as there is marked heterogeneity in its presentation and significant overlap with other disorders presenting with chest pain. Evidence is accumulating that cardiac MRI provides information that can aid the detection and differential diagnosis of ACS, guide clinical decision-making and improve risk-stratification after an event. In this review, we present the relevant cardiac MRI techniques that can be used to detect ACS accurately, provide differential diagnosis, identify the sequelae of ACS, and determine prognostication after ACS.

Thrombus Aspiration in ThrOmbus containing culpRiT lesions in Non-ST-Elevation Myocardial Infarction (TATORT-NSTEMI): study protocol for a randomized controlled trial

Background

Current guidelines recommend thrombus aspiration in patients with ST-elevation myocardial infarction (STEMI); however, there are insufficient data to unequivocally support thrombectomy in patients with non-STEMI (NSTEMI).

Methods/Design

The TATORT-NSTEMI (Thrombus Aspiration in ThrOmbus containing culpRiT lesions in Non-ST-Elevation Myocardial Infarction) trial is a prospective, controlled, multicenter, randomized, open-label trial enrolling 460 patients. The hypothesis is that, against a background of early revascularization, adjunctive thrombectomy leads to less microvascular obstruction (MO) compared with conventional percutaneous coronary intervention (PCI) alone, as assessed by cardiac magnetic resonance imaging (CMR) in patients with NSTEMI. Patients will be randomized in a 1:1 fashion to one of the two treatment arms. The primary endpoint is the extent of late MO assessed by CMR. Secondary endpoints include early MO, infarct size, and myocardial salvage assessed by CMR as well as enzymatic infarct size and angiographic parameters, such as thrombolysis in myocardial infarction flow post-PCI and myocardial blush grade. Furthermore, clinical endpoints including death, myocardial re-infarction, target vessel revascularization, and new congestive heart failure will be recorded at 6 and 12 months. Safety will be assessed by the incidence of bleeding and stroke.

Summary

The TATORT-NSTEMI trial has been designed to test the hypothesis that thrombectomy will improve myocardial perfusion in patients with NSTEMI and relevant thrombus burden in the culprit vessel reperfused by early PCI.

Trial registration

The trial is registered under http://www.clinicaltrials.gov: NCT01612312.

Obstructive sleep apnea and coronary artery disease: from pathophysiology to clinical implications

Coronary artery disease (CAD) and obstructive sleep apnea (OSA) are both complex and significant clinical problems. The pathophysiological mechanisms that link OSA with CAD are complex and can influence the broad spectrum of conditions caused by CAD, from subclinical atherosclerosis to myocardial infarction. OSA remains a significant clinical problem among patients with CAD, and evidence suggesting its role as a risk factor for CAD is growing. Furthermore, increasing data support that CAD prognosis may be influenced by OSA and its treatment by continuous positive airway pressure (CPAP) therapy. However, stronger evidence is needed to definitely answer these questions. This paper focuses on the relationship between OSA and CAD from the pathophysiological effects of OSA in CAD, to the clinical implications of OSA and its treatment in CAD patients.

Platelet count predicts cardiovascular mortality in very elderly patients with myocardial infarction

BACKGROUND

The prognosis of elderly patients with acute myocardial infarction (AMI) is poor, and information on specific risk factors remains scarce. The aim of our study was to assess the influence of platelet count on cardiovascular mortality in very elderly patients with acute myocardial infarction (≥ 85 years of age).

METHODS

We identified 208 elderly AMI patients and compared the platelet count with 208 matched young AMI patients (≤ 65 years) and 208 matched intermediate age AMI patients (66-84 years) who derived from the same cohort.

RESULTS

During a median follow-up of 4·7 years, 25% of patients (n = 156) died of cardiovascular causes (97 very elderly, 46 intermediate age and 13 young age patients). We detected a mean platelet count of 227G/l (SD ± 83) in very elderly AMI patients, of 236G/l (SD ± 78) in the intermediate AMI group and of 254G/l (SD ± 79) in 208 young AMI patients (ANOVA P = 0·002). We revealed a significant interaction between age and platelet count with regard to cardiovascular mortality (p for interaction = 0·014). Platelet count displayed a significant risk transformation from an independent risk factor for cardiovascular mortality in very elderly AMI patients (adj. hazard ratio (HR) per 1-SD increase 1·25;95%CI 1·02-1·54;P = 0·028), via displaying no association with mortality in the intermediate age group (P = 0·10), to a strong inverse association in young patients (adj. HR 0·36;95%CI 0·18-0·68;P = 0·002).

CONCLUSION

Our study demonstrates an independent association between elevated platelet count and long-term cardiovascular mortality in the growing and vulnerable group of very elderly AMI patients. Nevertheless, the pathophysiologic mechanisms underlying this age-dependent effect have to be further clarified.

Radial approach and single wiring as first intentional strategies in chronic total occlusions of the left anterior descending coronary artery

BACKGROUND

Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) of the left anterior descending coronary artery (LAD) specifically is associated with improved long-term 5 years survival as compared to PCI failure. Simpler PCI techniques may be successful and safer than complex techniques which are perceived to have high failure rates and technical complexity. We aimed to describe the safety and effectiveness of first intentional single wiring and radial approach in the treatment of patients with a CTO of the native LAD coronary artery at Toulouse Rangueil university hospitals.

PATIENTS AND METHODS

The study was a single center prospective registry. All patients showed evidence of myocardial viability in LAD territory. The operators' initial strategy was to start by a radial access as a first choice whenever feasible; if not, a femoral access was chosen. The initial strategy for lesion crossing in either antegrade or retrograde approaches was single wiring by lesion crossing using one guidewire (GW) as a simple technique.

RESULTS

A total of 30 patients with 30 LAD CTO lesions (100%) were recorded. Mean age was 71.6 + 15 years, 77% were males and 23% were females. The access route was radial 66% of the time and femoral 54% of the time and with double access for contralateral injection in 40% of the patients. Sheaths and catheters sizes 6F were used in 53% of the patients, and 7F in 73% of the patients. Overall lesion success rate was 83% of lesions. Single wiring was the prevailing technique used in 97% of successful lesions (83% of total cases), while only 3% were by multiple wiring techniques. Successful single antegrade wiring represented 63% of our total study cases with a GW success rate of 92% of cases. Successful single retrograde wiring represented 13% of our cases with a GW success rate of 67%. Q-wave myocardial infarction (MI), stent thrombosis, stroke, emergency coronary artery bypass graft (CABG), major bleeding, radiation dermatitis, cardiac tamponade or clinical perforation requiring any hemostatic maneuvers did not occur. There was a post-procedural Troponin rise of 3x normal levels in 30% of patients, and contrast induced nephropathy in 7%. Intra-aortic balloon counterpulsation (IABCP) was used in 3% of patients and cardiac death occurred in 3% of patients.

CONCLUSION

Single wiring and radial access as initial strategies in PCI for LAD-CTO lesions in either approaches antegrade or retrograde are associated with a high procedural success rate and an acceptable incidences of adverse events.

Are troponin assays occasionally deceiving us?

Troponin (I or T) is the principal marker of myocardial injury used in clinical practice. Although immune-based methods to determine troponin I levels are generally reliable, the presence of human antibodies interfering with the assays components could lead to erroneous results. In this report, we will discuss the case of a patient with misleadingly elevated troponin I due to high rheumatoid factor titer and provide an insight into the responsible molecular mechanisms.

Cardiac troponin assay classification by both clinical and analytical performance characteristics: a study on outcome prediction

BACKGROUND

Cardiac troponin assays have been classified according to whether they measure the 99th percentile concentration of a healthy reference population with imprecision (expressed as CV) of ≤10%, between 10% and 20%, or >20%. Assays in these categories have been deemed "guideline acceptable," "clinically usable," or "not acceptable," respectively. We compared four widely used "clinically usable" cardiac troponin I (cTnI) assays with an assay designated "not acceptable" for accuracy in predicting the clinical outcome of death.

METHODS

Blood was collected from 259 men and 249 women, mean (SD) age 68.8 (17.8) and 70.2 (17.8) years, respectively, admitted to the emergency department for suspected myocardial infarction. We measured cTnI by the Access, Architect, i-Stat, Stratus CS, and VIDAS assays. Deaths in this population were recorded over a 31-month period.

RESULTS

We found VIDAS cTnI assay measurement CVs of 10% and 20% at concentrations of 0.04 and 0.02 μg/L, respectively. Comparing at the 10% CV cutoff concentration, VIDAS cTnI was less sensitive than the Access and Architect assays (P < 0.001) but more sensitive than i-Stat (P < 0.001) and Stratus CS (P < 0.001) in identifying patients with poor outcomes. At the 20% CV cutoff, the VIDAS assay was equivalent to the other assays in identifying patients with poor outcomes.

CONCLUSIONS

For outcome prediction, the VIDAS cTnI assay was clinically equivalent or superior to other cTnI assays judged to be acceptable from a pure analytical standpoint. Thus, comparison of cardiac troponin assays should consider not only analytical performance, but also clinical performance characteristics.