Diagnostic Criteria For Acute Myocardial Infarction Research Articles

Prognostic role of acute myocardial infarction diagnostic criteria in patients presenting with non-ST segment elevation myocardial infarction

Abstract Background The Fourth Universal Definition of Myocardial Infarction (UDMI) defines acute myocardial infarction (AMI) as an acute myocardial injury associated with clinical evidence of acute myocardial ischemia. However, the prognostic role of each single diagnostic criteria has never been explored. Purpose To evaluate the prognostic role of the different diagnostic criteria of AMI according to the Fourth UDMI in patients with non-ST-segment elevation myocardial infarction. Methods We enrolled all consecutive patients with NSTEMI undergoing coronary angiography at our Centre. The admission diagnosis was performed according to the current guidelines criteria, namely the detection of an increase and/or decrease of high-sensitivity cardiac troponin I, with at least one value above the 99th percentile of the upper reference limit and at least one of the following: symptoms of ischemia, ECG changes (new ST depression or negative T-waves), echocardiographic evidence of new regional wall motion abnormality. Patients with very high-risk NSTEMI were excluded. Patients were then divided into different subgroups according to the combination of diagnostic criteria presented at admission. A composite endpoint of all-cause mortality, re-hospitalization for myocardial reinfarction or heart failure was collected. The predictive value of AMI diagnostic criteria alone and their combination were evaluated using Kaplan-Meier survival curves and subsequent Cox-regression analysis to find independent predictors of major adverse events. Results Our study population consisted of 2791 patients. The mean age was 68.3±13.4 and 31.5% were female. The mean follow-up time was 23.3±14.5 months. Depending on the AMI diagnostic criteria and their combination, patients were divided into three subgroups: 196 patients fulfilling only clinical criteria (group A), 187 with clinical and ECG-graphic criteria (group B) and 829 patients with clinical, ECG-graphic and echo-graphic criteria (group C). Baseline characteristics of the three groups were similar. At two-year follow-up, patients with clinical criteria alone exhibited the best outcome, whereas those with all three criteria fulfilled showed the worse prognosis (14.8% for group A vs 23.6% for group B vs 28.0% for group C; p-value <0.001). In multivariable Cox-regression model, the presence of clinical criteria alone was the independent predictor of better prognosis compared to the other diagnostic criteria combination (HR=0.48; CI 95% 0.31–0.74; p<0.001). Conclusions In non-very high-risk NSTEMI, not all diagnostic criteria have the same prognostic value. In fact, prognosis is significantly more favorable in patients exhibiting only the clinical criteria at admission. We hypothesize that the absence of ECG-graphic and echocardiographic alterations may indirectly indicate smaller infarct sizes that contribute to patients' outcomes. These findings could enhance the current risk stratification in patients admitted with NSTEMI. Funding Acknowledgement Type of funding sources: None.

P212 PROGNOSTIC ROLE OF ACUTE MYOCARDIAL INFARCTION DIAGNOSTIC CRITERIA IN NON–ST SEGMENT ELEVATION MYOCARDIAL INFARCTION

Abstract Background Although the majority of patients with NSTEMI share similar risk factors and similar pathophysiology, their outcomes differ considerably. The Fourth Universal Definition of Myocardial Infarction (UDMI) defined acute myocardial infarction (AMI) by an acute myocardial injury together with clinical evidence of acute myocardial ischaemia. However, the prognostic role of each single diagnostic criteria has never been explored. Purpose To evaluate the prognostic role of the different diagnostic criteria of AMI according to the Fourth UDMI in NSTEMI patients. Methods We enrolled all consecutive patients with AMI undergoing coronary angiogram at our Centre. We used a combination of criteria, according to the current ESC guidelines, to meet the diagnosis, namely the detection of an increase and/or decrease of high–sensitivity cardiac troponin I, with at least one value above the 99th percentile of the upper reference limit and at least one of the following: symptoms of ischaemia; ECG changes (new ST–T changes or new LBBB); development of pathological Q waves in the ECG; echocardiographic evidence of new loss of viable myocardium or new regional wall motion abnormality. Patients with STEMI and very high risk NSTEMI were excluded. A composite endpoint of all–cause mortality, re–hospitalization for heart failure, and myocardial reinfarction was collected. The predictive value of diagnostic criteria alone and their association were evaluated using Kaplan–Meier survival curves and subsequent Cox–regression analysis to find independent predictors of adverse events. Results 2791 patients with NSTEMI were evaluate. At admission 196 had clinical criteria alone, 187 had clinic + ECG and 829 had clinic + ECG + echo. The total number of events was 689. The median follow–up was 23.3±14.5 months. We found that patients with clinical criteria alone had a better prognosis at 2 years follow–up (p < 0.001). No other significant prognostic correlation was found. Multivariable Cox–regression model demonstrated that clinical criteria was the only independent predictor of better prognosis in patients with NSTEMI (HR = 0.48; CI 95% 0.31–0.74; p < 0.001). Conclusions Our data suggest that in NSTEMI the prognosis is considerably better if clinical criteria alone is present at admission. We hypothesize that the absence of electrocardiographic and echocardiographic alterations in NSTEMI could indirectly indicate smaller infarct sizes or other causes of acute myocardial injury.

249 Prognostic role of diagnostic criteria of acute myocardial infarction

Abstract Aims The term acute myocardial infarction (AMI) reflects cell death of cardiac myocytes caused by ischaemia. The Fourth Universal Definition of Myocardial Infarction (UDMI) defined AMI by a typical rise and fall in the level of biochemical markers of myocardial necrosis together with criteria of myocardial ischaemia. However, the prognostic role of each single diagnostic criteria has never been explored. To evaluate the prognostic role of the different diagnostic criteria of AMI according to the Fourth UDMI. Methods and results We enrolled all consecutive patients with AMI admitted from 2016 to 2019. We used a combination of criteria, according to the current ESC guidelines, to meet the diagnosis, namely the detection of an increase and/or decrease of high-sensitivity cardiac troponin I, with at least one value above the 99th percentile of the upper reference limit and at least one of the following: symptoms of ischaemia; ECG changes (new ST-T changes or new left bundle branch block); development of pathological Q waves in the ECG; imaging evidence of new loss of viable myocardium or new regional wall motion abnormality, in our study evaluated by transthoracic echocardiogram. All-cause mortality and a composite endpoint of all-cause mortality, re-hospitalization for heart failure, and myocardial re-infarction were collected. The predictive value of diagnostic criteria alone and its association were evaluated using Kaplan–Meier survival curves and subsequent Cox-regression analysis to find independent predictors of adverse events. 2386 patients were evaluated. The median follow-up time was 23.3 ± 14.5 months. The total number of events was 703 (29.5%). Kaplan–Meier curves showed that major adverse cardiac events (MACEs) were statistically different depending on the diagnostic criteria of AMI at admission. Particularly, clinical criteria alone showed a better predictive value (P < 0.001) than other diagnostic AMI criteria. Multivariable Cox-regression model demonstrated that clinical criteria were the independent predictor of good prognosis in patients with AMI (HR = 0.43; 95% CI: 0.28–0.67; P < 0.001). Conversely, the other diagnostic criteria (electrocardiographic and echocardiographic) and the combination of all diagnostic criteria were not independent prognostic factors of MACEs (HR = 1.1; 95% CI: 0.6–2.4, P = 0.6; HR = 1.1; 95% CI: 0.7–1.9, P = 0.6; HR = 0.9; 95% CI: 0.7–1.0, P = 0.2, respectively). Conclusions Our data suggest that the prognosis is considerably better among patients with a diagnosis of AMI if clinical criteria alone are present at admission. We also demonstrated that clinical criteria are a strong prognostic predictor of good outcomes in patients with AMI. We hypothesize that the absence of electrocardiographic and echocardiographic alterations could indirectly indicate a smaller infarct sizes that contribute to patients’ outcome.

251 Prognostic role of acute myocardial infarction diagnostic criteria in non-ST segment elevation myocardial infarction

Abstract Aims Although patients with ST segment elevation myocardial infarction (STEMI) and non-ST segment elevation myocardial infarction (NSTEMI) share similar risk factors and similar pathophysiology, their outcomes differ considerably. The Fourth Universal Definition of Myocardial Infarction (UDMI) defined acute myocardial infarction (AMI) by an acute myocardial injury together with clinical evidence of acute myocardial ischaemia. However, the prognostic role of each single diagnostic criteria has never been explored. To evaluate the prognostic role of the different diagnostic criteria of AMI according to the Fourth UDMI in patients with STEMI vs. NSTEMI. Methods and results We enrolled all consecutive patients with AMI undergoing coronary angiogram at our Centre. We used a combination of criteria, according to the current ESC guidelines, to meet the diagnosis, namely the detection of an increase and/or decrease of high-sensitivity cardiac troponin I, with at least one value above the 99th percentile of the upper reference limit and at least one of the following: symptoms of ischaemia; ECG changes (new ST-T changes or new left bundle branch block); development of pathological Q waves in the ECG; echocardiographic evidence of new loss of viable myocardium, or new regional wall motion abnormality. According to the ECG presentation at admission, patients with AMI were divided into STEMI and NSTEMI subgroups. All-cause mortality and a composite endpoint of all-cause mortality, re-hospitalization for heart failure, and myocardial re-infarction were collected. The predictive value of diagnostic criteria alone and their association was evaluated using Kaplan–Meier survival curves and subsequent Cox-regression analysis to find independent predictors of adverse events. 2345 patients were evaluated (41.6% STEMI and 58.4% NSTEMI). The two groups had similar baseline characteristics. The total number of events was 689 (292 in STEMI group and 397 in NSTEMI group). We found that clinical criteria alone showed a positive predictive value in NSTEMI (P < 0.001). Moreover, electrocardiographic and echocardiographic criteria correlated with a worse prognosis in STEMI group (P < 0.01). No other significant prognostic correlation was found. Multivariable Cox-regression model demonstrated that clinical criteria were the only independent predictors of better prognosis in patients with NSTEMI (HR = 0.48; 95% CI: 0.31–0.74; P < 0.001). We did not find any predictor of outcome in patients with STEMI (HR = 0.6; 95% CI: 0.3–1.5, P = 0.3; HR = 1.1; 95% CI: 0.5–2.6, P = 0.7; HR = 0.6; 95% CI: 0.3–1.2, P = 0.2 for clinical and echocardiographic criteria alone and their combination, respectively). Conclusions Our data suggest that in NSTEMI the prognosis is considerably better if clinical criteria alone are present at admission. We hypothesize that the absence of electrocardiographic and echocardiographic alterations in NSTEMI could indirectly indicate smaller infarct sizes or other causes of acute myocardial injury.

Prognostic role of diagnostic criteria of acute myocardial infarction

Abstract Background The term acute myocardial infarction (AMI) reflects cell death of cardiac myocytes caused by ischaemia. The Fourth Universal Definition of Myocardial Infarction (UDMI) defined AMI by a typical rise and fall in the level of biochemical markers of myocardial necrosis together with criteria of myocardial ischaemia. However, the prognostic role of each single diagnostic criteria has never been explored. Purpose To evaluate the prognostic role of the different diagnostic criteria of AMI according to the Fourth UDMI. Methods We enrolled all consecutive patients with AMI admitted from 2016 to 2019. We used a combination of criteria, according to the current ESC guidelines, to meet the diagnosis, namely the detection of an increase and/or decrease of high-sensitivity cardiac troponin I, with at least one value above the 99th percentile of the upper reference limit and at least one of the following: symptoms of ischaemia; ECG changes (new ST-T changes or new LBBB); development of pathological Q waves in the ECG; imaging evidence of new loss of viable myocardium or new regional wall motion abnormality, in our study evaluated by transthoracic echocardiogram. All-cause mortality and a composite endpoint of all-cause mortality, re-hospitalization for heart failure and myocardial re-infarction were collected. The predictive value of diagnostic criteria alone and its association were evaluated using Kaplan-Meier survival curves and subsequent Cox-regression analysis to find independent predictors of adverse events. Results 2386 patients were evaluated. The median follow-up time was 23.3±14.5 months. The total number of events was 703 (29.3%). Kaplan-Meier curves showed that major adverse cardiac events (MACE) were statistically different depending on the diagnostic criteria of AMI at admission. Particularly, clinical criteria alone showed a better predictive value (p<0.001) than other diagnostic AMI criteria. Multivariable Cox-regression model demonstrated that clinical criteria was the independent predictor of good prognosis in patients with AMI (HR=0.43; CI 95% 0.28–0.67; p<0.001). Conversely, the others diagnostic criteria (electrocardiographic and echocardiographic) and the combination of all diagnostic criteria were not independent prognostic factors of MACE (HR=1.1 CI 95% 0.6–2.4, p=0.6; HR=1.1 CI 95% 0.7–1.2, p=0.6; HR=0.9 CI 95% 0.7–1.0, p=0.8 respectively). Conclusions Our data suggest that the prognosis is considerably better among patients with a diagnosis of AMI if clinical criteria alone are present at admission. We also demonstrated that clinical criteria are a strong prognostic predictor of good outcomes in patients with AMI. We hypothesize that the absence of electrocardiographic and echocardiographic alterations could indirectly indicate a smaller infarct sizes that contribute to patients' outcome. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): None

Explaining trends in coronary heart disease hospitalisations in New Zealand: trend for admissions and incidence can be in opposite directions

Background:A recent increase in the absolute number of hospitalisations for acute myocardial infarction (AMI) in New Zealand may signal a new epidemic of coronary heart disease (CHD).Objective:To quantify the impact...

Impact of redefining acute myocardial infarction on incidence, management and reimbursement rate of acute coronary syndromes

Background Although redefinition for acute myocardial infarction (AMI) has been proposed few years ago, to date it has not been universally adopted by many institutions. The purpose of this study is to evaluate the diagnostic, prognostic and economical impact of the new diagnostic criteria for AMI. Methods Patients consecutively admitted to the emergency department with suspected acute coronary syndromes were enrolled in this study. Troponin T (cTnT) was measured in samples collected for routine CK-MB analyses and results were not available to physicians. Patients without AMI by traditional criteria and cTnT ≥ 0.035 ng/mL were coded as redefined AMI. Clinical outcomes were hospital death, major cardiac events and revascularization procedures. In-hospital management and reimbursement rates were also analyzed. Results Among 363 patients, 59 (16%) patients had AMI by conventional criteria, whereas additional 75 (21%) had redefined AMI, an increase of 127% in the incidence. Patients with redefined AMI were significantly older, more frequently male, with atypical chest pain and more risk factors. In multivariate analysis, redefined AMI was associated with 3.1 fold higher hospital death (95% CI: 0.6–14) and a 5.6 fold more cardiac events (95% CI: 2.1–15) compared to those without AMI. From hospital perspective, based on DRGs payment system, adoption of AMI redefinition would increase 12% the reimbursement rate [Int $3552 per 100 patients evaluated]. Conclusions The redefined criteria result in a substantial increase in AMI cases, and allow identification of high-risk patients. Efforts should be made to reinforce the adoption of AMI redefinition, which may result in more qualified and efficient management of ACS.

The new definition of myocardial infarction-Can we use it?

A joint committee of the European Society of Cardiology and the American College of Cardiology (ESC/ACC) recently redefined myocardial infarction. The objective of this study was to examine the outcome of diagnoses from more than 500 patients admitted to a university hospital coronary care unit (CCU), when the ESC/ACC committee cut-off levels were compared with the Swedish diagnostic criteria for acute myocardial infarction (MI), comparable with everyday practice in most countries. Creatine kinase-MB, troponin I, and troponin T were measured in 525 patients admitted consecutively to the CCU, Huddinge University Hospital, with possible myocardial ischemia lasting <12 h before arrival. The ESC/ACC definition of MI increased the number of MIs by 3-32% compared with the number achieved when Swedish diagnostic criteria for acute MI were used. A significant number of patients with elevated cardiac enzymes presented with acute heart failure, tachycardia, pulmonary embolism, and sepsis as initial symptom. In this study of more than 500 patients with possible myocardial ischemia admitted consecutively to the CCU at a university hospital, the ESC/ACC definition of MI increased the number of MIs by 3-32% compared with the number achieved when Swedish diagnostic criteria for acute MI were used. A majority of the patients identified with ESC/ACC cut-off levels presented with myocardial ischemia as the primary symptom, whereas many of the other patients had acute heart failure and tachycardia as initial symptom. It is unclear whether patients in this latter group should be labelled as having MI; there are no clinical studies providing guidance in this situation.

Changes in hospitalization rate and mortality after acute myocardial infarction in Denmark after diagnostic criteria and methods changed

To analyse the effect of the change in diagnostic criteria for acute myocardial infarction (AMI) and the use of troponin as a diagnostic marker on the hospitalization rate and mortality of hospitalized AMI patients from 1994 to 2001. Patients (> or =30 years) admitted for their first AMI were identified using the National Patient Registry in Denmark. We registered when each hospital introduced troponin as a diagnostic marker. The reported hospitalization rate decreased until 1998 and then increased substantially from 1999 to 2001 from 3472 to 4163 per million inhabitants (19.9%) for men and from 1648 to 2020 per million inhabitants (22.6%) for women. Troponin use was associated with a significant 14% increase in hospitalization rate in this period [rate ratio 1.14, 95% confidence interval (CI) 1.11-1.18]. The effect of troponin was greatest among patients 70 years and older (rate ratio 1.19, 95% CI 1.14-1.23). The 28 day mortality decreased steadily from 25.9% in 1994 to 17.5% in 2002 (32.4%) and was not affected by troponin use. The reported hospitalization rate for AMI increased significantly after the new diagnostic criteria for AMI were introduced. The measurement of cardiac troponins further increased the hospitalization rate. The mortality among hospitalized patients with AMI declined steadily and was not affected by the use of troponins.

Recent time trends in acute myocardial infarction in Stockholm, Sweden

Aims: The purpose of this study was to analyse time trends in first acute myocardial infarction (AMI) incidence in Stockholm County during 1984–1996. Methods and results: The study base consisted of the population of Stockholm County 30–89 years old 1984–1996. New cases of first AMI in the study base were identified by combining information regarding hospital discharges and deaths. The diagnostic quality was evaluated for 2403 First-AMI cases 45–70 years old that occurred during 1992–1994. The evaluation indicated a very high agreement with diagnostic criteria of AMI among hospital treated cases. Among fatal cases outside hospital, the autopsy rate was nearly 70%. The incidence of first AMI declined during the study period for both men and women. In men, the age-adjusted incidence of first AMI was 18% lower in 1994–1996 than in 1984–1987 and in women it was 13% lower. The average yearly decline was 2% for men and 1.4% for women. Conclusion: The results of this study suggest a continued decline in AMI incidence in Stockholm. A reduction in the proportion of regular smokers has probably contributed to this decline. Future trends in AMI incidence are difficult to predict in view of diverging trends in risk factors.

Chemistry: Cost-Effective Utilization of CK-MB Mass and Activity Assays

Effective use of creatine kinase M and B isoform (CK-MB) test results for the diagnosis or exclusion of acute myocardial infarction (AMI) requires repeated analyses at defined intervals after the onset of chest pain. An increase in serum CK-MB is evaluated relative to typical angina-like chest pain of at least 30 minutes duration and electrocardiographic changes per World Health Organization (WHO) standards. Two or more of the three findings must be abnormal for the diagnosis of AMI. We assessed the appropriateness (clinical usefulness) and cost-effectiveness of CK-MB mass and activity levels in the care of patients with complaints of chest pain seen in our emergency department. The total CK and CK-MB (mass and activity) results for 860 patients during 2 months in 1995 were reviewed retrospectively relative to the discharge diagnosis. According to the discharge diagnoses based on the WHO diagnostic criteria for AMI, only 54 patients (6.3%) had acute myocardial infarction. Three or more CK-MB tests (mass and activity measurements) were performed in 60.5% of patients, and only one test was performed in the remaining 39.5%. Abnormal CKMB mass or activity was determined with the following criteria: Protocol 1: CK-MB mass >5 ng/mL, total CK >194 U/L, index >2.5%; Protocol 2: CK-MB activity >16 U/L, total CK >65 U/L, index >5%; Protocol 3: CK-MB activity >10 U/L, total CK >65 U/L, index >2.2%. Based on these criteria, CK-MB mass and activity protocols gave positive predictive values of 38.2%, 36.1%, and 35.4% for protocols 1, 2, and 3, respectively. The negative predictive value was 99% for CKMB mass (Protocol 1), and 98% and 98.9% for CK-MB activity (Protocols 2 and 3). These results indicate that both CK-MB mass and activity protocols have equivalent clinical usefulness. However, given the technologic limitation of two platforms for Protocol 1 vs one assay platform for Protocols 2 and 3, the CK-MB activity protocol is more cost-effective for patient testing in the emergency department laboratory.

Are geographical differences and time trends in myocardial infarction incidence in sweden real? Validity of hospital discharge diagnoses

In Sweden, acute myocardial infarction (AMI) incidence has been found to differ considerably between the neighboring counties of Stockholm and Gävleborg, with an increase in Stockholm during the 1970s. We estimated the AMI incidence in Stockholm in 1973 and in both areas in 1981. To determine if there were differences in the validity of hospital discharge diagnoses, random samples of AMI patients were examined for diagnostic criteria for AMI. In both genders, AMI incidence was higher in Gävleborg than in Stockholm (relative risk (RR) 1.34 for men and 1.21 for women) and increased in Stockholm from 1973 to 1981 (RR 1.21 for men and 1.29 for women). The proportion of patients fulfilling the diagnostic criteria for AMI was similar in both areas in 1981 but 10% less in Stockholm in 1981 than in 1973. These results suggest that differences in the validity of hospital discharge diagnoses cannot explain the geographical differences in AMI incidence, but that this may have contributed to the increasing incidence seen in Stockholm county.