British Cardiac Society Working Group on the definition of myocardial infarction

Incidence of myocardial injury in patients submitted to carotid endarterectomy

Myocardial injury following noncardiac surgery (MINS) is associated with higher mortality and major adverse cardiovascular event rates in the short- and long-term in patients undergoing carotid endarterectomy (CEA). However, its incidence is still unclear in this subset of patients. Therefore, this systematic review with meta-analysis aims to determine the incidence of MINS in patients undergoing CEA. Three electronic databases MEDLINE, Scopus, and Web of Science were used to search for studies assessing the occurrence of MINS in the postoperative setting of patients undergoing CEA. The incidence of MINS was pooled by random-effects meta-analysis, with sources of heterogeneity being explored by meta-regression and subgroup analysis (general anesthesia vs. regional anesthesia). Assessment of studies' quality was performed using National Heart, Lung, and Blood Institute Study Quality Assessment Tool, and Risk of Bias 2 tools. Twenty studies were included, with a total of 117,933 participants. Four of them were RCTs, while the remaining were cohort studies. All observational cohorts had an overall high risk of bias, except for Pereira Macedo et al. Three of them had repeated population, thus only data from the most recent one was considered. On the other hand, all RCT had an overall low risk of bias. In patients under regional anesthesia, the incidence of MINS in primary studies ranged between 2% and 15.3%, compared to 0-42.5% for general anesthesia. The meta-analytical incidence of MINS after CEA was of 6.3% [95% CI 2.0-10.6%], but severe heterogeneity was observed (I2=99.1%). MINS appears to be relatively common among patients undergoing CEA. The observed severe heterogeneity points to the need for further larger studies adopting consistent definitions of MINS and equivalent cut-off values.

Coagulation F13A1 V34L, fibrinogen and homocysteine versus conventional risk factors in the pathogenesis of MI in young persons

BACKGROUND

The pathogenesis of myocardial infarction (MI) involves environmental and genetic risk factors, with the latter putatively playing significant roles in younger patients. Genetic variability in coagulation factors comprises one such group. The coagulation factor 13 subunit A (F13A1) Val34Leu polymorphism (rs5985) has yielded variable findings in literature, with no prior South Asian data.

METHODS

We studied the frequency of this polymorphism using the amplification-created restriction-enzyme site (ACRES) polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in 101 MI patients aged below 40 years and 103 controls along with plasma fibrinogen and serum homocysteine levels.

RESULTS

The distribution of Val/Val, Val/Leu and Leu/Leu genotypes was similar among cases (72.3%, 26.7% and 1.0%) and controls (78.6%, 19.4% and 1.9%, respectively). Val and Leu allele frequencies were 85.6% and 14.4% among patients and 88.3% and 11.7% among controls, respectively (p = .416). Mean plasma fibrinogen was higher in patients vis-à-vis controls (3.1 versus 3.7 g/l; p < .001) but homocysteine was elevated in both patients (52%) and controls (67%) (p = .225). Multivariate analysis revealed hypertension (p < .001, OR 6.16) and smoking (p < .001, OR 5.48) to impart strongest risk followed by positive family history, plasma fibrinogen levels and male gender.

CONCLUSIONS

Despite its small sample size, this first South Asian study suggests neither protective nor deleterious effects of the F13A1 Val34Leu polymorphism on the risk of MI in young persons. The Leu allele frequency is intermediate to that reported from the West and the Far East. Traditional risk factors contribute greatly to risk even in younger MI patients in South Asia.

Gender peculiarities of the risk of cardiovascular diseases in a population with symptoms of depression in Siberia (the WHO MONICA-psychosocial program)

Aim. To identify gender differences in the prevalence of depression in an open population of individuals aged 25—64 years and to evaluate its impact on the risk of cardiovascular diseases (CVD) in the population of Siberia. Subjects and methods. A random representative sample of a 25—64-year-old Novosibirsk population (657 men and 689 women) was surveyed within the framework of the third screening of the WHO MONICA-psychosocial program in 1994. The screening program included sociodemographic data registration and depression detection. Over a 16-year study period, women had myocardial infarction (MI) in 15 cases and stroke in 35 cases and men had these conditions in 30 and 22 cases, respectively. Results. In the open 25—64-year-old population, depression was detected in 54.5% of the women and in 29% of the men; major depression was present in 11.8% of the women and 3.1% of the men (χ2=66.724; υ=2; p=0.0001). The risk of MI in the depressed patients was higher in the women (hazard ratio (HR)=2.5) than in the men (HR=2); when social parameters and age are included in the model, only a trend towards the impact of depression on the risk of MI persisted in the women (HR=3.4; p>0.05) and the men were observed to have a 1.6-fold higher risk for MI. The greatest risk of MI was seen in the men (HR=6.8) and women (HR=6.3) at the age of 55—64 years, as well as in the men who had incomplete secondary or primary education (HR=3.2); in blue-collar workers (HR=6.7), in the men who were single (HR=3.6), divorced (HR=4.5), or widowed (HR=6). The risk of stroke in the depressed patients during a 16-year study period was greater in the men (HR=5.8) than in the women (HR=4.6); after adjusting for age and social gradient, the risk of stroke in the women was higher in both the population and those who were aged 55—64 years (HR=8.5 and 6.9, respectively) than that in the men (HR=4.2 and 3.1, respectively). Among the men, the risk of stroke was higher in those who had primary education (HR=8.8), were widowed (HR=8.4) or divorced (HR=2.7). Conclusion. The women are much more susceptible to depression than are the men. The risk of MI with depression is higher in the women than in the men; at the same time, the risk of stroke is higher in the men than in the women. The picture is opposite in the older age group. The risk of CVD in the depressed men is exacerbated by a social gradient; these relationships have not been revealed in the women.

Cardiac magnetic resonance assessment of diastolic dysfunction in acute coronary syndrome

Chest pain is an important presenting symptom. However, few cases of chest pain are diagnosed as acute coronary syndrome (ACS) in the acute setting. This results in frequent inappropriate discharge and major delay in treatment for patients with underlying ACS. The conventional methods of assessing ACS, which include electrocardiography and serological markers of infarct, can take time to manifest. Recent studies have investigated more sensitive and specific imaging modalities that can be used. Diastolic dysfunction occurs early following coronary artery occlusion and its detection is useful in confirming the diagnosis, risk stratification, and prognosis post-ACS. Cardiac magnetic resonance provides a single imaging modality for comprehensive evaluation of chest pain in the acute setting. In particular, cardiac magnetic resonance has many imaging techniques that assess diastolic dysfunction post-coronary artery occlusion. Techniques such as measurement of left atrial size, mitral inflow, and mitral annular and pulmonary vein flow velocities with phase-contrast imaging enable general assessment of ventricular diastolic function. More novel imaging techniques, such as T2-weighted imaging for oedema, T1 mapping, and myocardial tagging, allow early determination of regional diastolic dysfunction and oedema. These findings may correspond to specific infarcted arteries that may be used to tailor eventual percutaneous coronary artery intervention.

The Use of Biomarkers for the Early Detection of Vulnerable Atherosclerotic Plaques and Vulnerable Patients. A Review

Acute coronary syndromes represent the most severe consequences of atherosclerosis, most often triggered by the rupture of a coronary plaque, which, for various reasons, has become unstable. In many cases, these rupture-prone vulnerable plaques are difficult to diagnose, because they do not always cause significant obstruction noticeable by coronary angiography. Therefore, new methods and tools for the identification of vulnerable plaques have been proposed, many of which are currently under study. Various biomarkers have been suggested as predictors of a vulnerable plaque, as well as indicators of an increased inflammatory status associated with higher patient susceptibility for plaque rupture. Integration of such biomarkers into multiple biomarker platforms has been suggested to identify superior diagnostic algorithms for the early detection of the high-risk condition associated with an unstable plaque. The aim of this review is to summarize recent research related to biomarkers used for the early detection of vulnerable plaques and vulnerable patients.

Cardiovascular disease risk profiles among ‘healthy’ siblings of patients with early-onset cardiovascular disease: application of the new SCORE system

Background

Cardiovascular disease (CVD) occurs more frequently in individuals with a family history of premature CVD. Within families the demographics of CVD are poorly described.

Design

We examined the risk estimation based on the Systematic Coronary Risk Evaluation (SCORE) system and the Joint British Guidelines (JBG) for older unaffected siblings of patients with premature CVD (onset ≤ 55 years for men and ≤ 60 years for women).

Methods

Between August 1999 and November 2003 laboratory and demographic details were collected on probands with early-onset CVD and their older unaffected siblings. Siblings were screened for clinically overt CVD by a standard questionnaire and 12-lead electrocardiogram (ECG).

Results

A total of 790 siblings was identified and full demographic details were available for 645. The following siblings were excluded: 41 with known diabetes mellitus; seven with random plasma glucose of 11.1 mmol/l or greater; and eight with ischaemic ECG. Data were analysed for 589 siblings from 405 families. The mean age was 55.0 years, 43.1% were men and 28.7% were smokers. The mean total serum cholesterol was 5.8 mmol/l and hypertension was present in 49.4%. Using the SCORE system, when projected to age 60 years, 181 men (71.3%) and 67 women (20.0%) would be eligible for risk factor modification. Using JBG with a 10-year risk of 20% or greater, 42 men (16.5%) and four women (1.2%) would be targeted.

Conclusions

Large numbers of these asymptomatic individuals meet both European and British guidelines for the primary prevention of CVD and should be targeted for risk factor modification. The prevalence of individuals defined as eligible for treatment is much higher when using the SCORE system.

Decision limits and the reporting of cardiac troponin: Meeting the needs of both the cardiologist and the ED physician

Cardiac troponin is the preferred biomarker for defining the acute coronary syndrome and acute myocardial infarction. Currently, the only decision limit formally endorsed with regard to the cardiac troponins is the 99th percentile. This is a "rule-in" criterion, intended to ensure that only persons with the acute coronary syndrome are reviewed. The 99th percentile is an arbitrary cut point and there are many problems associated with its application, including defining a truly healthy population, the difficulty of standardisation of cardiac troponin assays, especially but not only cardiac troponin I, and the effects of age and sex on this parameter. The Emergency Department (ED) screens many more persons for possible acute coronary syndromes than actually have the condition and their needs are best met by a "rule-out" test that enables them to clear their busy departments of the many persons who do not actually have the condition. The needs of the ED are not optimally met using the 99th percentile. The index of individuality for the cardiac troponins is small and significant changes consistent with an acute coronary syndrome can occur without the 99th percentile being exceeded. It appears that the ED may be better served by use of delta troponin changes rather than the 99th percentile, but there are problems with this approach, particularly in persons who present late when troponin release has plateaued. In addition, there are many non-acute coronary syndrome causes for cardiac troponin release. The needs of the cardiologist and the ED physician are so different that it may be inappropriate for both groups to use the same diagnostic criteria for cardiac troponin, and it is of great importance that cardiac troponin measurement be used as only one part of the assessment of the person presenting with possible acute coronary syndrome.

Association between the -794 (CATT)5-8 MIF gene polymorphism and susceptibility to acute coronary syndrome in a western Mexican population

The macrophage migration inhibitory factor (MIF) is related to the progression of atherosclerosis, which, in turn, is a key factor in the development of acute coronary syndrome (ACS). MIF has a CATT short tandem repeat (STR) at position -794 that might be involved in its expression rate. The aim of this study was to investigate the association between the -794 (CATT)5-8  MIF gene polymorphism and susceptibility to ACS in a western Mexican population. This research included 200 ACS patients classified according to the criteria of the American College of Cardiology (ACC) and 200 healthy subjects (HS). The -794 (CATT)5-8  MIF gene polymorphism was analyzed using a conventional polymerase chain reaction (PCR) technique. The 6 allele was the most frequent in both groups (ACS: 54% and HS: 57%). The most common genotypes in ACS patients and HS were 6/7 and 6/6, respectively, and a significant association was found between the 6/7 genotype and susceptibility to ACS (68% versus 47% in ACS and HS, resp., P = 0.03). We conclude that the 6/7 genotype of the MIF -794 (CATT)5-8 polymorphism is associated with susceptibility to ACS in a western Mexican population.

Diagnostic accuracy of exercise stress testing for coronary artery disease: a systematic review and meta-analysis of prospective studies

BACKGROUND

Exercise stress testing offers a non-invasive, less expensive way of risk stratification prior to coronary angiography, and a negative stress test may actually avoid angiography. However, previous meta-analyses have not included all exercise test modalities, or patients without known Coronary artery disease (CAD).

METHODS AND RESULTS

We systematically reviewed the literature to determine the diagnostic accuracy of exercise stress testing for CAD on angiography. MEDLINE (January 1966 to November 2009), MEDION (1966 to July 2009), CENTRAL (1966 to July 2009) and EMBASE (1980-2009) databases were searched for English language articles on diagnostic accuracy of exercise stress testing. We included prospective studies comparing exercise stress testing with a reference standard of coronary angiography in patients without known CAD. From 6,055 records, we included 34 studies with 3,352 participants. Overall, we found published studies regarding five different exercise testing modalities: treadmill ECG, treadmill echo, bicycle ECG, bicycle echo and myocardial perfusion imaging. The prevalence of CAD ranged from 12% to 83%. Positive and negative likelihood ratios of stress testing increased in low prevalence settings. Treadmill echo testing (LR+ = 7.94) performed better than treadmill ECG testing (LR+ = 3.57) for ruling in CAD and ruling out CAD (echo LR- = 0.19 vs. ECG LR- = 0.38). Bicycle echo testing (LR+ = 11.34) performed better than treadmill echo testing (LR+ = 7.94), which outperformed both treadmill ECG and bicycle ECG. A positive exercise test is more helpful in younger patients (LR+ = 4.74) than in older patients (LR+ = 2.8).

CONCLUSIONS

The diagnostic accuracy of exercise testing varies, depending upon the age, gender and clinical characteristics of the patient, prevalence of CAD and modality of test used. Exercise testing, whether by echocardiography or ECG, is more useful at excluding CAD than confirming it. Clinicians have concentrated on individualising the treatment of CAD, but there is great scope for individualising the diagnosis of CAD using exercise testing.

The paradox of the 21st century - is there really an epidemic of most common killers?

Over the last 110 years, average global life expectancy has more than doubled from 31 years of age to 65 years of age. This trend is expected to continue, and many of the children born after the year 2000 can expect to live to celebrate their hundredth birthday. In the last 20 years alone, average life expectancy has increased globally by 6 years.DURING THE SAME PERIOD, DOCTORS HAVE ANNOUNCED A GLOBAL EPIDEMIC OF THE MOST COMMON KILLERS: cardiovascular disease, diabetes, chronic kidney, and chronic obstructive pulmonary disease. One of the most important reasons for the more frequent recognition of these diseases is the fact that their diagnostic criteria have changed and become much more acute during the past few years.These changes in diagnostic criteria have made it difficult, or even impossible, to compare the present statistical data regarding these diseases to historical data for the same illnesses. Due to this difficulty, there is no evidence-based comparison of the prevalence of any disease at present and in the past. Before announcing a global epidemic, a fair epidemiological comparison should be made, based upon the same definitions and using identical diagnostic tools.

An assessment of the concentration-related prognostic value of cardiac troponin I following acute coronary syndrome

In 2004 the British Cardiac Society redefined myocardial infarction by cardiac troponin I (cTnI) concentration: ≤ 0.06 μg/L (unstable angina), >0.06 to < 0.5 μg/L (myocardial necrosis), and ≥ 0.5 μg/L (myocardial infarction). We investigated the effects of this classification on all-cause mortality in 1,285 patients from the Evaluation of the Methods and Management of Acute Coronary Events (EMMACE)-2 registry. There were 528 deaths (6.6-year all-cause mortality 41.1%). Survival was greatest in the cTnI ≤ 0.06-μg/L subgroup at 30 days (p = 0.005), 6 months (p = 0.015), 1 year (p = 0.002), and 6.6 years (p = 0.045). After adjustment there was no significant difference in survival between the cTnI >0.06- to < 0.5-μg/L and ≥ 0.5-μg/L subgroups. Increased mortality (hazard ratio, 95% confidence interval) was associated with ages 70 to 80 years (2.58, 1.17 to 3.91) and >80 years (3.30, 3.50 to 5.06), peripheral vascular disease (1.50, 1.16 to 1.94), heart failure (1.36, 1.05 to 1.83), diabetes mellitus (1.68, 1.36 to 2.07), severe left ventricular systolic dysfunction (1.50, 1.00 to 2.21), and creatinine per 10 μmol/L (1.65, 1.02 to 1.08), whereas ages 50 to 60 years (0.55, 0.32 to 0.96), β blockers (0.53, 0.44 to 0.64), aspirin (0.80 0.65 to 0.99), angiotensin-converting enzyme inhibitors (0.67, 0.56 to 0.80), statins (0.73, 0.59 to 0.90), and revascularization (0.33, 0.12 to 0.92) were associated with a lower risk of death. In conclusion, although quantitative evaluation of cTnI concentration in patients with acute coronary syndrome with cTnI > 0.06 μg/L was associated with no added prognostic information, the dichotomization of patients by cTnI status ("positive" and "negative") facilitates acute coronary syndrome risk stratification.

Relative Familial Clustering of Cerebral Versus Coronary Ischemic Events

Background—

Few population-based studies have ascertained both cerebral and coronary events or considered their relative heritability. Differences in heritability of transient ischemic attack and ischemic stroke versus acute coronary syndromes (ACS) may inform risk prediction, genetic studies, and understanding of disease mechanisms.

Methods and Results—

In a population-based study of all acute vascular events, irrespective of age, we studied family history of myocardial infarction (MI), stroke, and related risk factors in first-degree relatives. To allow for differences in rates of affected first-degree relatives caused by differences in disease incidence, we looked at the extent to which parental history was associated with affected siblings within disease category. Nine hundred six probands (604 men; mean age, 70 years) with ACS and 1015 (484 men; mean age, 73 years) with cerebral events had complete family history data. In ACS probands, parental MI was associated with MI in ≥1 sibling (1 parent with MI: odds ratio, 1.48; 1.04 to 2.10; P =0.03; both parents with MI: odds ratio, 5.97; 3.23 to 11.03; P <0.0001). In probands with cerebral events, however, parental stroke was not associated with sibling stroke. The overall frequency of ≥2 siblings with the same condition was also greater in probands with ACS than in those with cerebral events (odds ratio, 5.43; 3.03 to 9.76; P <0.00001), despite similar overall incidence of MI and stroke in our study population. One hundred forty-two (15.7%) cases of ACS occurred in families with ≥2 affected first-degree relatives compared with 56 (5.1%) transient ischemic attack/strokes. All results were similar when analyses were confined to probands with MI only versus stroke only, and independent of smoking.

Conclusions—

Heritability of coronary events was greater than that of cerebral events, such that MI was more likely to cluster in families than was stroke.

Familial history of stroke is associated with acute coronary syndromes in women

BACKGROUND

Stroke in female first-degree relatives (FDRs) is a powerful risk factor for ischemic stroke in women, but its association with acute coronary syndromes (ACS) is unknown. Family history (FH) of stroke is omitted from existing myocardial infarction risk prediction tools, which perform less well in women than in men. Our objective was to study the sex-of-parent and sex-of-proband interactions for FH of stroke in ACS patients.

METHODS AND RESULTS

In a prospective, population-based study (Oxford Vascular Study) of all patients with ACS or stroke/transient ischemic attack, FH data for stroke and myocardial infarction were analyzed by sex of proband and FDRs, and coronary angiograms were reviewed, where available; 942 of 1058 ACS probands and 1015 of 1152 stroke/transient ischemic attack probands had complete FH data; 24.1% of ACS probands and 24.3% of stroke/transient ischemic attack probands had history of stroke in ≥1 FDR. Maternal stroke was more common than paternal stroke in female ACS probands (odds ration [OR], 2.53; 1.39 to 4.61) but not in male probands (OR, 0.92; 0.64 to 1.32) (difference-P=0.004). Overall, female ACS probands were more likely to have female than male FDRs with stroke (OR, 2.09; 1.29 to 3.37), whereas the opposite trend was seen in male ACS probands (OR, 0.69; 0.50 to 0.97) (difference-P=0.0002). However, there was no association between parental history of stroke and disease localization or presence of multivessel disease on coronary angiography.

CONCLUSIONS

FH of stroke is as common in ACS patients as in stroke/transient ischemic attack patients and sex-of-parent/sex-of-proband interactions are similar. Stroke in female FDRs may help to identify women at increased risk of ACS as well as ischemic stroke.

Do inter-hospital comparisons of in-hospital, acute myocardial infarction case-fatality rates serve the purpose of fostering quality improvement? An evaluative study

BACKGROUND

In-hospital case-fatality rates in patients, admitted for acute myocardial infarction (AMI-CFRs), are internationally used as a quality indicator. Attempting to encourage the hospitals to assume responsibility, the Belgian Ministry of Health decided to stimulate initiatives of quality improvement by means of a limited set of indicators, among which AMI-CFR, to be routinely analyzed. In this study we aimed, by determining the existence of inter-hospital differences in AMI-CFR, (1) to evaluate to which extent Belgian discharge records allow the assessment of quality of care in the field of AMI, and (2) to identify starting points for quality improvement.

METHODS

Hospital discharge records from all the Belgian short-term general hospitals in the period 2002-2005. The study population (N = 46,287) included patients aged 18 years and older, hospitalized for AMI. No unique patient identifier being present, we tried to track transferred patients. We assessed data quality through a comparison of MCD with data from two registers for acute coronary events and through transfer and sensitivity analyses. We compared AMI-CFRs across hospitals, using multivariable logistic regression models. In the main model hospitals, Charlson's co-morbidity index, age, gender and shock constituted the covariates. We carried out two types of analyses: a first one wherein transferred-out cases were excluded, to avoid double counting of patients when computing rates, and a second one with exclusion of all transferred cases, to allow the study of patients admitted into, treated in and discharged from the same hospital.

RESULTS

We identified problems regarding both the CFR's numerator and denominator.Sensitivity analyses revealed differential coding and/or case management practices. In the model with exclusion of transfer-out cases, the main determinants of AMI-CFR were cardiogenic shock (OR(adj) 23.0; 95% CI [20.9;25.2]), and five-year age groups OR(adj) 1.23; 95% CI [1.11;1.36]). Sizable inter-hospital and inter-type of hospital differences {(OR(comunity vs tertiary hospitals)1.36; 95% CI [1.34;1.39]) and (OR(intermediary vs tertiary hospitals)1.36; 95% CI [1.34;1.39])}, and nonconformities to guidelines for treatment were observed.

CONCLUSIONS

Despite established data quality shortcomings, the magnitude of the observed differences and the nonconformities constitute leads to quality improvement. However, to measure progress, ways to improve and routinely monitor data quality should be developed.

Cardiac rehabilitation uptake following myocardial infarction: cross-sectional study in primary care

BACKGROUND

Policies suggest that primary care should be more involved in delivering cardiac rehabilitation. However, there is a lack of information about what is known in primary care regarding patients' invitation or attendance.

AIM

To determine, within primary care, how many patients are invited to and attend rehabilitation after myocardial infarction (MI), examine sociodemographic factors related to invitation, and compare quality of life between those who do and do not attend.

DESIGN OF STUDY

Review of primary care paper and computer records; cross-sectional questionnaire.

SETTING

Northern Ireland general practices (38); stratified sample, based on practice size and health board area.

METHOD

Patients, identified from primary care records, 12-16 weeks after a confirmed diagnosis of MI, were posted questionnaires, including a validated MacNew post-MI quality-of-life questionnaire. Practices returned anonymised data for non-responders.

RESULTS

Information about rehabilitation was available for 332 of the 432 patients identified (76.9%): 162 (37.5%) returned questionnaires. Of the total sample, 54.4% (235/432) were invited and 37.0% (160/432) attended; of those invited, 68.1% (160/235) attended. Invited patients were younger than those not invited (mean age 63 years [standard deviation SD 16] versus 68.5 years [SD 16]); mean difference 5.5 years (95% confidence interval [CI] = 1.7 to 9.3). Among questionnaire responders, those who attended were younger and reported better emotional, physical, and social functioning than non-attenders (P = 0.01; mean differences 0.44 (95% CI = 0.11 to 0.77), 0.48 (95% CI = 0.10 to 0.85) and 0.54 (95% CI = 0.15 to 0.94) respectively).

CONCLUSION

Innovative strategies are needed to improve cardiac rehabilitation uptake, integration of hospital and primary care services, and healthcare professionals' awareness of patients' potential for health gain after MI.

Assessment of acute myocardial infarction: current status and recommendations from the North American society for Cardiovascular Imaging and the European Society of Cardiac Radiology

There are a number of imaging tests that are used in the setting of acute myocardial infarction and acute coronary syndrome. Each has their strengths and limitations. Experts from the European Society of Cardiac Radiology and the North American Society for Cardiovascular Imaging together with other prominent imagers reviewed the literature. It is clear that there is a definite role for imaging in these patients. While comparative accuracy, convenience and cost have largely guided test decisions in the past, the introduction of newer tests is being held to a higher standard which compares patient outcomes. Multicenter randomized comparative effectiveness trials with outcome measures are required.

Short term impact of smoke-free legislation in England: retrospective analysis of hospital admissions for myocardial infarction

OBJECTIVE

To measure the short term impact on hospital admissions for myocardial infarction of the introduction of smoke-free legislation in England on 1 July 2007.

DESIGN

An interrupted time series design with routinely collected hospital episode statistics data. Analysis of admissions from July 2002 to September 2008 (providing five years' data from before the legislation and 15 months' data from after) using segmented Poisson regression.

SETTING

England. Population All patients aged 18 or older living in England with an emergency admission coded with a primary diagnosis of myocardial infarction.

MAIN OUTCOME MEASURES

Weekly number of completed hospital admissions.

RESULTS

After adjustment for secular and seasonal trends and variation in population size, there was a small but significant reduction in the number of emergency admissions for myocardial infarction after the implementation of smoke-free legislation (-2.4%, 95% confidence interval -4.06% to -0.66%, P=0.007). This equates to 1200 fewer emergency admissions for myocardial infarction (1600 including readmissions) in the first year after legislation. The reduction in admissions was significant in men (3.1%, P=0.001) and women (3.8%, P=0.007) aged 60 and over, and men (3.5%, P<0.01) but not women (2.5% P=0.38) aged under 60.

CONCLUSION

This study adds to a growing body of evidence that smoke-free legislation leads to reductions in myocardial infarctions. It builds on previous work by showing that such declines are observed even when underlying reductions in admissions and potential confounders are controlled for. The considerably smaller decline in admissions observed in England compared with many other jurisdictions probably reflects aspects of the study design and the relatively low levels of exposure to secondhand smoke in England before the legislation.

Session 4: CVD, diabetes and cancer Evidence for the use of the Mediterranean diet in patients with CHD

Diet is associated with the development of CHD. The incidence of CHD is lower in southern European countries than in northern European countries and it has been proposed that this difference may be a result of diet. The traditional Mediterranean diet emphasises a high intake of fruits, vegetables, bread, other forms of cereals, potatoes, beans, nuts and seeds. It includes olive oil as a major fat source and dairy products, fish and poultry are consumed in low to moderate amounts. Many observational studies have shown that the Mediterranean diet is associated with reduced risk of CHD, and this result has been confirmed by meta-analysis, while a single randomised controlled trial, the Lyon Diet Heart study, has shown a reduction in CHD risk in subjects following the Mediterranean diet in the secondary prevention setting. However, it is uncertain whether the benefits of the Mediterranean diet are transferable to other non-Mediterranean populations and whether the effects of the Mediterranean diet will still be feasible in light of the changes in pharmacological therapy seen in patients with CHD since the Lyon Diet Heart study was conducted. Further randomised controlled trials are required and if the risk-reducing effect is confirmed then the best methods to effectively deliver this public health message worldwide need to be considered.

Statins, ACE inhibitors and ARBs in cardiovascular disease

Atherosclerotic cardiovascular disease (CVD) is the main cause of death in developed and developing countries. It is well accepted that several diseases - including hypertension, dyslipidemia and diabetes mellitus - increase CVD. More recently also chronic inflammatory diseases, such as rheumatoid arthritis, have been shown to accelerate CVD. This association further supports a responsible role for inflammatory processes in all stages of CVD pathophysiology. Clinically, CVD ranges through different acute and chronic syndromes with ischemic symptoms in distal tissues, including heart, cerebral region or peripheral arteries. Several treatments for reducing CVD are under investigation. In this review we focus on statins, angiotensin-converting-enzyme (ACE) inhibitors, and angiotensin-II receptor blockers (ARBs), updating therapeutic evidence from the last clinical trials with particular relevance to diabetic patients.

Sex-Specific Familial Clustering of Myocardial Infarction in Patients With Acute Coronary Syndromes

Background— Family history of premature myocardial infarction (MI) in first-degree relatives is a risk factor for MI and an indication for primary prevention. Although excess mother-to-daughter “transmission” occurs in ischemic stroke, no published studies have considered sex-of-parent/sex-of-proband interactions in the heritability of MI.

Methods and Results— In a population-based study (Oxford Vascular Study) of all patients with acute coronary syndromes (ACS), irrespective of age, family history of all acute vascular events and related risk factors were analyzed by sex and age of both probands and first-degree relatives. Premature events were categorized as occurring at age <65 years. Of 835 probands with 1 or more ACS, 623 (420 men) had incident events and complete family history data. In probands with premature ACS, maternal history of both MI and of all vascular events were more common in female than male probands (odds ratio [OR], 2.25; 95% CI, 1.02 to 4.94; P =0.04 and OR, 3.03; 95% CI, 1.47 to 6.26; P =0.002, respectively). No such effect existed for paternal history (OR, 1.00; 95% CI, 0.46 to 2.10; P =0.99 and OR, 1.19; 95% CI, 0.58 to 2.43; P =0.63, respectively). Age at ACS in probands was highly correlated with age at MI in mothers ( r =0.46, P <0.001), regardless of the proband’s sex. Consequently, history of premature maternal MI was strongly associated with premature ACS and premature MI in female (OR, 10.52; 95% CI, 2.17 to 56.6; P =0.001 and OR, 7.31; 95% CI, 1.55 to 34.6; P =0.004, respectively) and male probands (OR, 3.88; 95% CI, 1.20 to 12.6; P =0.01 and OR, 3.63; 95% CI, 1.13 to 11.60; P =0.02, respectively).

Conclusions— Important sex-of-parent/sex-of-proband interactions exist in the family history of MI in patients with ACS. Greater emphasis should be placed on maternal than paternal history of MI, particularly in women aged <65 years.

Secondary prevention of myocardial infarction with nonpharmacologic strategies in a Medicaid cohort

BACKGROUND

The quality of health care after myocardial infarction (MI) may be lacking; in particular, guidelines for nonpharmacologic interventions (cardiac rehabilitation, smoking cessation) may receive insufficient priority. We identified gaps between secondary prevention guidelines and ambulatory care received by Medicaid enrollees after an MI.

METHODS

MI survivors were selected by using 2004 Washington State Medicaid administrative claims. Deidentified data were abstracted for hospitalizations, ambulatory care, and prescriptions for 365 days after the MI. Cox regression analysis compared utilization of guideline-directed secondary prevention strategies with death and recurrent hospitalization.

RESULTS

The sample size was 372. Fifty patients died during the year after the MI, and 144 were rehospitalized. Only 2 patients attended a cardiac rehabilitation program. Tobacco cessation counseling was associated with a 66% reduction in death, but only 72.6% of smokers were counseled. Less than half (45.4%) of patients saw a primary care provider within 90 days of their MI, and 7.5% never contacted a health care provider. Receiving regular primary care was associated with a decreased risk for death (hazard ratio, 0.91; 95% confidence interval, 0.84-0.97, P < .01). A protective trend was associated with care by a cardiologist, but only 21.5% received specialist care.

CONCLUSION

Analysis of Medicaid claims data suggests rates of secondary prevention are less than optimal. To improve survival and reduce rehospitalization after an MI, policy changes (tobacco cessation benefits, expansion of rehabilitation programs), health care capacity (training, referral patterns, and coordination of care), and improvements to access (removing barriers, increasing facilities, targeting minority populations) could be implemented.

The use of risk scores for stratification of non-ST elevation acute coronary syndrome patients

OBJECTIVE

To review the methods available for the risk stratification of non-ST elevation (NSTE) acute coronary syndrome (ACS) patients and to evaluate the use of risk scores for their initial risk assessment.

DATA SOURCES

The data of the present review were identified by searching PUBMED and other databases (1996 to 2008) using the key terms "risk stratification", "risk scores", "NSTEMI", "UA" and "acute coronary syndrome".

STUDY SELECTION

Mainly original articles, guidelines and critical reviews written by major pioneer researchers in this field were selected.

RESULT

After evaluation of several risk predictors and risk scores, it was found that estimating risk based on clinical characteristics is challenging and imprecise. Risk predictors, whether used alone or in simple binary combination, lacked sufficient precision because they have high specificity but low sensitivity. Risk scores are more accurate at stratifying NSTE ACS patients into low-, intermediate- or high-risk groups. The Global Registry of Acute Cardiac Events risk score was found to have superior predictive accuracy compared with other risk scores in ACS population. Treatments based according to specific clinical and risk grouping show that certain benefits may be predominantly or exclusively restricted to higher risk patients.

CONCLUSION

Based on the trials in the literature, the Global Registry of Acute Cardiac Events risk score is more advantageous and easier to use than other risk scores. It can categorize a patient's risk of death and/or ischemic events, which can help tailor therapy to match the intensity of the patient's NSTE ACS.

Temporal change in glucose tolerance in non-ST-elevation myocardial infarction

We assessed the prevalence and 3-month change in glucose tolerance status in consecutive non-ST-elevation myocardial infarction (NSTEMI; European Society of Cardiology 2007 definition) patients (N=49; mean (S.D.) age 65 (11) years) admitted to a coronary care unit, without known diabetes. These patients underwent an oral glucose tolerance test (OGTT) 36-hour (median, IQR: 18-72) after admission and at 3 months. Undiagnosed abnormal glucose tolerance (AGT: impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or new diabetes) was common (61% at admission and 41% at 3 months, p<0.05) and the majority (approximately 3/4) had IGT. Glucose tolerance status improved in a higher proportion of patients than it worsened (31% vs. 8%, p=0.04). At 3 months, fasting glucose was unchanged but 2-hour OGTT glucose was lower (mean (S.D.): 8.5 (2.7) mmol/L vs. 7.7 (2.7) mmol/L, p=0.004). 'Stress hyperglycaemia' could explain higher admission glucose levels and this raises the question about the optimal timing of OGTT in relation to myocardial infarction. Newly diagnosed diabetes was present in approximately 10% of patients and this was not reliably detected by fasting plasma glucose. In NSTEMI patients OGTT is the only reliable strategy to identify subjects with IGT and diabetes.

Medication Management Among Medicaid Myocardial Infarction Survivors

Despite guidelines to direct appropriate medical management, the quality of care following acute myocardial infarction (AMI) may be lacking. This study characterizes medication utilization by Medicaid enrollees in the year following AMI, compares it to guidelines for secondary prevention and investigates associations with rehospitalization and survival. Using DSHS administrative claims data from Washington State, Medicaid enrollees who had an AMI in 2004 were selected. Data were de-identified and details of demographics, hospitalizations, ambulatory care, and prescriptions over the following 365 days were abstracted. Utilization of guideline-directed secondary prevention strategies was measured and associations with death and recurrent hospitalization were tested. The mortality rate was 13.4% and 38.7% were rehospitalized. Mean time to first rehospitalization was 188.6 days (SD 102.3). Prescriptions for angiotensin enzyme inhibitors or receptor blockers were initially filled by 54.0%, but year-long adherence declined to 33.3%. Beta blockers, aspirin and statins followed the same trend: 65.1% to 39.5%, 37.9% to 16.7% and 58.1% to 41.9% respectively. Twenty-two percent received all medications; 8.2% were adherent. Only the initial prescription of aspirin was significantly associated with a survival benefit (HR = 0.35, p=0.003). If the results suggested by the claims data are representative of care delivered to Medicaid enrollees, rates of application of guideline-directed medication are less than optimal. To improve survival and reduce re-hospitalization following AMI, changes in the access and delivery of healthcare could be implemented to improve medication management, both at time of discharge and over the year following AMI.

Limitation of myocardial infarct size in the clinical setting: current status and challenges in translating animal experiments into clinical therapy

This review takes a critical look at the current effectiveness of reperfusion therapy for acute myocardial infarction and at the potential for cardioprotective agents to improve it. Reperfusion alone limits the median value of infarct size to approximately 50% of the ischemic region. However, the range of infarct sizes is very wide, and one-fourth of these patients have more than 75% of the ischemic zone infarcted despite successful coronary reperfusion. Available studies suggest that mortality and morbidity is increased when more than 20% of the left ventricle is infarcted. Therefore, to be effective infarct size-limiting therapy would have to reduce infarction to or below this 20% target. To achieve this goal in the quartile of patients with the biggest infarcts the cardioprotective agent would have to be potent enough to reduce infarct size from its current value of 75% of the ischemic zone to 40% or less. While ischemic preconditioning and some pretreatment drugs might be potent enough to achieve this goal, few of the agents given at the clinically relevant time of at or just before reperfusion have exhibited such potency. Several cardioprotective agents have recently been evaluated in clinical trials but their results have been disappointing. Some of the poor clinical trial performance may stem from study designs which fail to identify those patients falling within the upper quartile of infarct sizes, presumably the only group that would be expected to actually benefit from a reduction in infarct size. Other possible causes could be that co-morbidities or drugs patients are taking may block the pathways involved in the anti-infarct effect or that the drugs simply do not protect even in animal models. Few agents have been thoroughly tested in clinically relevant animal models prior to their testing in man.

Management of acute coronary syndrome

This is a review of acute coronary syndrome as a clinical entity. An appreciation of acute coronary syndrome as a disease spectrum is presented along with contemporary evidence for its diagnosis and approach to medical and surgical management.

The new and old definitions of acute myocardial infarction: a data-based comparison

PURPOSE

To measure the agreement between the newer European Society of Cardiology-American College of Cardiology (ESC-ACC) definition of acute myocardial infarction (AMI) and the traditional definition established by the World Health Organization (WHO).

BASIC PROCEDURES

All adult ED patients admitted to our institution with at least one abnormally elevated cardiac biomarker were determined to have had an AMI by either or both definitions. The degree of agreement and the frequency of the reasons for disagreement between these 2 definitions were measured.

MAIN FINDINGS

A final study population consisted of 339 patients; 196 (58%) had an AMI by one or both definitions. Among them, 126 (64%; 95% confidence interval [CI], 57-71) were discordant for these 2 definitions: 104 (53%; 95% CI, 46-60) met only the ESC-ACC, whereas 22 (11%; 95% CI, 6-16) met only the WHO definition. Among those who met only the ESC-ACC definition, 37 (36%; 95% CI, 27-45) met none of the 3 traditional WHO criteria.

PRINCIPAL CONCLUSIONS

More patients are discordant than concordant for the 2 standard definitions of AMI. Among them, a large majority meet only the new ESC-ACC definition.

Prospective study of cardiac troponin I release in patients with upper gastrointestinal bleeding

BACKGROUND AND AIM

The rate of cardiac injury in upper gastrointestinal hemorrhage is unclear. The aims of this study were to determine prospectively the risk of cardiac troponin I release and associated adverse cardiac events in patients with acute upper gastrointestinal hemorrhage.

METHODS

From January to September 2003, we prospectively studied patients with documented hematemesis and melena referred to the gastroenterology unit in a tertiary teaching hospital in Melbourne, Australia. Serial assays for cardiac troponin I were performed at 0, 12 and 24 h. Serial creatine kinase levels and electrocardiographs were also performed. Clinical and biochemical data were collected. The primary endpoint was a troponin level >0.5 microg/L within 24 h of recruitment. Various clinical variables were then compared between the groups of patients with or without troponin rise.

RESULTS

A total of 156 patients were included in the study. The mean age was 67 years (range 19-96). There were 104 (67%) male patients. A troponin level of greater than 0.5 microg/L was found in 30/156 (19%); 126 (81%) patients had normal troponin levels. Age greater than 65 years, signs of hemodynamic instability at presentation, a recent history of cardiac disease, cardiovascular compromise following endoscopy, and re-bleeding were associated with troponin release.

CONCLUSION

Upper gastrointestinal bleeding is associated with a risk of cardiac injury of up to 19%. Troponin assay could be used to screen for cardiac damage, especially in elderly patients who present with hemodynamic instability.

Population-based register of acute myocardial infarction: manual of operations

Cardiovascular disease is the leading cause of death and hospitalization in both sexes in nearly all countries of Europe. The main forms of cardiovascular disease are ischaemic heart disease and stroke. The magnitude of the problem contrasts with the shortage, weak quality and comparability of data available in most European countries. Innovations in medical, invasive and biological treatments have substantially contributed to the escalating costs of health services. It is therefore urgent to obtain reliable information on the magnitude and distribution of the disease for both adequate health planning (including preventive strategies) and clinical decision making with correct cost-benefit assessments.A stepwise surveillance procedure based on standardized data collection, appropriate record linkage and validation methods was set up by the EUROCISS Project (EUROpean Cardiovascular Indicators Surveillance Set) to build up comparable and reliable indicators (attack rate and case fatality) for the surveillance of acute myocardial infarction/acute coronary syndrome at population level. This manual of operations is intended for health professionals and policy makers and provides a standardized and simple model for the implementation of a population-based register. It recommends to start from a minimum data set and then follow a stepwise procedure. Before implementing a population-based register, it is important to identify the target population under surveillance which should preferably cover a well-defined geographical and administrative area or region representative of the whole country for which population data and vital statistics (mortality and hospital discharge records at minimum) are routinely collected and easily available each year. All cases among residents should be recorded even if the case occurs outside the area. Validation of a sample of fatal and nonfatal events is mandatory.

Hyperglycaemia, in relation to sex, and mortality after acute coronary syndrome

AIMS

Both diabetes mellitus (DM) and hyperglycaemia are known to predict outcome after acute coronary syndrome (ACS). Recent work has suggested women with DM have greater baseline cardiovascular risk and poorer outcome after ACS. The interaction between sex and abnormal glucose homoeostasis in patients without diabetes is unexplored; we aimed to assess this relationship.

METHODS AND RESULTS

Retrospective analysis of data from a prospective cohort study of 1575 patients with a confirmed ACS and no previous diagnosis of DM in 11 UK hospitals. Multivariable analysis was performed to assess the value of clinical variables, including hyperglycaemia and sex, in predicting 2 year all-cause mortality. Sex and hyperglycaemia interacted in predicting mortality. In men, mortality risk increased more steeply with incremental levels of glycaemia than in women (glucose > or =11.1 mmol/l, hazard ratio, 2.19; 95% confidence interval, 1.2-4.0). In both sex groups increasing glycaemia predicted mortality at levels currently not recommended for acute therapeutic intervention (7.8-11.0 mmol/l).

CONCLUSIONS

In patients not known to have diabetes, hyperglycaemia is a concentration-dependent predictor of long-term mortality after ACS; this predictive value is stronger in men than women.

Aspirin and mortality in patients with diabetes sustaining acute coronary syndrome

OBJECTIVE

We sought to compare mortality reduction associated with secondary prevention in patients with and without diabetes after acute coronary syndrome (ACS).

RESEARCH DESIGN AND METHODS

We conducted a cohort study involving 2,499 patients with ACS recruited from 11 U.K. hospitals. Multivariable analysis comparing all-cause mortality risk reduction associated with pharmacologic agents in patients with and without diabetes.

RESULTS

Aspirin was not associated with significant mortality benefit in diabetes sufferers (95% CI 0.50-1.08); nondiabetic patients derived a 48% mortality reduction (P < 0.001). The interaction between diabetes and aspirin use was statistically significant (P = 0.037), indicating that patients with diabetes experience less effective mortality reduction from aspirin use.

CONCLUSIONS

Aspirin, but not other secondary prevention agents, is associated with less effective mortality reduction in patients with diabetes and unstable coronary artery disease.

Prospective survey of serial troponin T requesting in an acute teaching hospital

BACKGROUND

Requests for troponin T, a biomarker for myocardial infarction, may be sent in a variety of clinical situations. In most cases, a single sample 12 hours or more after symptom onset should be sufficient for diagnosis. We chose to investigate how troponin T testing is used in our hospital with emphasis on those who had serial rather than single troponin measurements during their hospital stay.

METHODS

Prospective survey of 50 patients with serial troponin T requests out of a total of 321 patients who had troponin T levels measured during the same time period.

RESULTS

The time of symptom onset could be clearly identified in 40/50 patients. In 22 of these the first troponin was taken prior to 12 hours after symptom onset. For the 18 patients whose first troponin was taken after 12 hours, the second result remained in the same category (normal or high) as the first in all cases. This was not the case for 3/10 patients whose first troponin was sent within 12 hours and was normal. Early troponin results rarely affected immediate patient management and did not inform decisions about fibrinolytic therapy.

CONCLUSIONS

Serial troponin testing was most commonly due to a sample being sent within 12 hours of symptom onset or to unnecessary repetition of an appropriately timed sample. Patient management was rarely enhanced by early troponin testing.

Epidemiology of myocardial infarction

Myocardial infarction is a key component of the burden of cardiovascular disease. The assessment of the incidence and case fatality of myocardial infarction are important determinants of the decline in coronary disease mortality. The change in biomarkers used to diagnose myocardial infarction raises several methodologic, clinical, and public health challenges, which are discussed herein.

Potential value for new diagnostic markers in the early recognition of acute coronary syndromes

The diagnostic approach to acute coronary syndromes (ACS) remains one of the most difficult and controversial challenges facing emergency physicians. In recent years, cardiac troponins have emerged as the biochemical "gold standard" for diagnosis of patients with acute chest pain, enhancing our ability to recognize ACS. Early diagnosis and treatment of myocardial ischemia improve patient outcomes, but conventional markers are often nondiagnostic at the time of arrival at the emergency department. Promising new biomarkers, which appear earlier after the onset of ischemia, are being studied and integrated into clinical practice. Some are markers of myocyte necrosis, but others, including ischemia-modified albumin and natriuretic peptides, detect myocardial ischemia and myocardial dysfunction. The aim of the present article is to review the diagnostic approach to ACS, focusing on recent literature describing novel biochemical markers. If ongoing and future studies confirm their role in probability-based models risk assessment, a new era in the diagnostic approach to ACS may be dawning.

Determinants of plasma homocysteine in relation to hematological and biochemical variables in patients with acute myocardial infarction

BACKGROUND

Elevated plasma total homocysteine (tHcy) is a risk factor for coronary artery disease (CAD), but the mechanism is not known. This study evaluates the determinants and associations of tHcy in patients presenting with acute myocardial infarction (AMI).

METHODS

Plasma concentration of tHcy, protein C, protein S, and antithrombin were measured in 210 (177 males and 33 females) patients with first AMI and 167 (87 males and 80 females) controls. Serum vitamin B12, folate, creatinine, lipid profile, fasting glucose, full blood count and red cell folate were determined. Creatinine clearance was calculated using the modification of diet in renal disease formula. Univariate and multivariate analyses were used to determine the associations of tHcy.

RESULTS

Mean tHcy was higher in male than female patients. On logistic regression analysis, the most important determinants oftHcy in the patients were age, creatinine, creatinine clearance, vitamin B12 and red cell folate. When study patients were compared with the controls, tHcy, fasting glucose and serum creatinine were significantly higher, while creatinine clearance and HDL cholesterol were significantly lower in the study patients. Logistic regression analysis showed significant association of tHcy with AMI, odds ratio = 1.39, in the presence of other confounding factors.

CONCLUSIONS

Our results show that tHcy is a significant risk factor for CAD in our patient population. The determinants in the patients are age, glomerular filtration rate and the status of vitamins B12 and folate. The above determinants should be kept in mind when using tHcy as a risk factor for CAD.

Funnel plots, performance variation and the Myocardial Infarction National Audit Project 2003-2004

Background

Clinical governance requires health care professionals to improve standards of care and has resulted in comparison of clinical performance data. The Myocardial Infarction National Audit Project (a UK cardiology dataset) tabulates its performance. However funnel plots are the display method of choice for institutional comparison. We aimed to demonstrate that funnel plots may be derived from MINAP data and allow more meaningful interpretation of data.

Methods

We examined the attainment of National Service Framework standards for all hospitals (n = 230) and all patients (n = 99,133) in the MINAP database between 1^st April 2003 and 31^st March 2004. We generated funnel plots (with control limits at 3 sigma) of Door to Needle and Call to Needle thrombolysis times, and the use of aspirin, beta-blockers and statins post myocardial infarction.

Results

Only 87,427 patients fulfilled criteria for analysis of the use of secondary prevention drugs and 15,111 patients for analysis by Door to Needle and Call to Needle times (163 hospitals achieved the standards for Door to Needle times and 215 were within or above their control limits). One hundred and sixteen hospitals fell outside the 'within 25%' and 'more than 25%' standards for Call to Needle times, but 28 were below the lower control limits. Sixteen hospitals failed to reach the standards for aspirin usage post AMI and 24 remained below the lower control limits. Thirty hospitals were below the lower CL for beta-blocker usage and 49 outside the standard. Statin use was comparable.

Conclusion

Funnel plots may be applied to a complex dataset and allow visual comparison of data derived from multiple health-care units. Variation is readily identified permitting units to appraise their practices so that effective quality improvement may take place.

Transient left ventricular dysfunction with apical ballooning (tako-tsubo cardiomyopathy) in Germany

AIMS

A peculiar type of an acute coronary syndrome is characterised by acute onset of chest pain, STsegment changes, elevated troponin I levels and a transient balloon-like apical left ventricular dysfunction, but without significant coronary artery disease. We sought to assess this syndrome in German patients.

METHODS AND RESULTS

A total of 22 females and 1 male with acute transient left ventricular dysfunction were identified during an interval of 2 years and were investigated clinically and angiographically. All patients presented without obstructive coronary artery disease. In 16 patients (70%) ST-segment elevations were observed mimicking acute myocardial infarction, whereas the remaining patients (30%) revealed only negative T waves. Deep negative Twaves were characteristically seen during the course of recovery in all patients. Elevated troponin I levels>2.0 microg/l (upper level of normal) were measured in all patients (mean 18+/-26.5 microg/l, range from 2.2-135.7 microg/l). Creatine kinase rose up to a mean of 282+/-236 IU/l (upper level of normal 180 U/l). Emotional or physical stress situations associated with the onset of the symptoms were observed in 16 patients (70%). Other suspected trigger factors were gastrointestinal infection and in one case a surgical intervention. In four patients a trigger factor could not be identified. Left ventriculography showed an ejection fraction of 53+/-15%. After an interval of 7+/-2 days after the first angiogram, ejection fraction had increased from 48+/-11% to 64+/-11% in eight controlled patients by repeated ventriculography. Coronary spasm with a lumen reduction>75% could be provoked using acetylcholine in 10 of 17 tested patients (59%) with reproduction of the symptoms. Within 14 days the LV dysfunction returned to normal in all patients. The ECG abnormalities disappeared completely as early as 3 months (74%) and were not seen in any patient after 6 months.

CONCLUSION

Tako-tsubo cardiomyopathy is not exclusively a Japanese or Northern American phenomenon. Despite increased patient reports the exact underlying cause and pathophysiology of this syndrome remain unclear. However, despite the initial dramatic presentation of this disease the prognosis is good.

Management and outcomes of acute coronary syndrome with minimal myocardial necrosis: analysis of a large prospective registry from a non-interventional centre

The aim of this study was to assess the clinical risk of minimal myonecrosis below the cut-off for acute myocardial infarction (MI) in comparison with other grades of acute coronary syndrome (ACS). One-thousand four hundred and sixty seven consecutive patients with ACS admitted between May 2001 and April 2002 were studied in a non-interventional centre. Patients were divided into unstable angina (UA) (cTnT < 0.01 microg/l), non-ST elevation ACS with minimal myonecrosis (0.01 <or= cTnT < 0.1 microg/l), non-ST elevation MI (NSTEMI) (cTnT >or= 0.1 microg/L) and ST elevation myocardial infarction (STEMI). UA (n = 638) was associated with the fewest events at 6 months (2% cardiac death or MI). Patients with any myonecrosis (n = 829) had worse outcomes (6-month cardiac death or MI 18.3-23.3%). Compared with ACS patients with minimal myonecrosis, UA patients were at significantly lower risk (OR 0.21, 95% CI 0.12-0.45, p < 0.001), NSTEMI patients were at similar risk (OR 1.45, 95% CI 0.89-2.35, p = 0.13), and STEMI patients were at higher risk (OR 2.12 95% CI 1.26-3.85, p = 0.008) in adjusted analyses. Nearly 85% of cardiac deaths occurred within 6 months. The risk of adverse events was higher among patients managed by non-cardiologists (OR 1.66, 95% CI 1-2.75, p = 0.049). Patients with non-ST elevation ACS and minimal myonecrosis are a high-risk group more comparable with NSTEMI and clearly distinguishable from patients with UA.

Relationship between perioperative troponin elevation and other indicators of myocardial injury in vascular surgery patients

BACKGROUND

In 2000 the European Society of Cardiology and the American College of Cardiology published a consensus document revising the definition of myocardial infarction. The usefulness of this revised definition has been challenged. It has been suggested that, rather than any release of cardiac troponin being potentially diagnostic of myocardial infarction, a diagnostic threshold consistent with significant myocardial injury should be defined.

METHODS

We studied 65 patients undergoing elective major vascular surgery to examine the relationship between the magnitude of cardiac troponin I (cTnI) and creatine kinase MB fraction (CK-MB) release and clinical signs or symptoms of myocardial injury. cTnI and CK-MB concentrations were measured preoperatively and on the first 4 postoperative days using the ACCESS assay (Beckmann). Patients were considered to have suffered a perioperative myocardial infarction if they had either symptoms or ECG changes consistent with this diagnosis, together with cTnI release.

RESULTS

Peak postoperative cTnI concentrations above the lower detection limit of the ACCESS assay (0.06 microg litre(-1)) occurred in 26 patients. Eight of these patients displayed symptoms or ECG changes consistent with myocardial injury. A cTnI level greater than 0.68 microg litre(-1) was found to be consistent with the clinical diagnosis of myocardial infarction. The optimal cut-off for the diagnosis of MI using CK-MB was 40.4 microg litre(-1).

CONCLUSIONS

These data suggest that further studies are required to define the optimal cardiac troponin diagnostic threshold for the diagnosis of myocardial infarction in the non-cardiac surgery population.

The new definition of myocardial infarction and the impact of troponin determination on clinical practice

OBJECTIVE

To discuss the more controversial clinical and laboratory aspects in the application of the new biochemical diagnostic standard for myocardial infarction, 4 years after its introduction, and to make some suggestions, which could allow for a more realistic application of the new definition in the current clinical practice.

METHODS

Studies published in the last 4 years in the most important cardiology and laboratory medicine journals (including proceedings of the international meetings), discussing advantages and limits of the new definition of myocardial infarction, were reviewed and pertinent data were discussed and compared with similar information available in literature.

RESULTS AND CONCLUSIONS

Although the exact status of implementation of the new definition of myocardial infarction cannot yet be known, the trend toward such recommendation is evolving significantly, even if at different rates in different countries. To make the transition smoother, major educational efforts are required to disseminate the conceptual reasoning behind the new guidelines. On the other hand, more knowledge is needed for some relevant issues, such as the different analytical performance of cardiac troponin assays or the prognostic significance of biomarker changes after a percutaneous coronary intervention.