Publish in this journal
Journal Information
Vol. 72. Issue 4.
Pages 353-355 (April 2019)
Scientific letter
DOI: 10.1016/j.rec.2018.03.022
Full text access
Clinical Acceptance of the Universal Definition of Myocardial Infarction
Aceptación clínica de la definición universal del infarto de miocardio
Visits
...
German Cediela,
Corresponding author
gecediel@yahoo.com

Corresponding author:
, Maribel González-del-Hoyob, Gil Bonetb, Anna Carrasquerb, Carme Boquéc, Alfredo Bardajíb
a Departamento de Cardiología, Hospital Universitario Germans Trias i Pujol, Badalona, Barcelona, Spain
b Departamento de Cardiología, Hospital Universitario Joan XXIII, Tarragona, Spain
c Servicio de Urgencias, Hospital Universitario Joan XXIII, Tarragona, Spain
This item has received
...
Visits
(Daily data update)
Article information
Full Text
Bibliography
Download PDF
Statistics
Tables (2)
Table 1. Patients’ Baseline Clinical Characteristics of the Patients According to the Department Issuing the Discharge Report
Table 2. Analysis of Concordance Between the Diagnoses in the Discharge Reports and the Classification According to the Universal Definition of MI in the Overall Sample and by the Department Issuing the Report
Show moreShow less
Full Text
To the Editor,

In the emergency department, troponin determination is a useful test to differentiate between non–ST-segment myocardial infarction (MI) and unstable angina. Acute and chronic myocardial lesions due to a large spectrum of cardiac and noncardiac causes are recognizable in clinical practice.1 In 2007, the universal definition of MI established the classification of patients according to the etiology of the condition.2 Since then, the term type 2 MI has been used to describe clinical conditions associated with an ischemic myocardial lesion in the absence of complicated atheromatous plaques. Although several studies have reported higher mortality rates in patients with type 2 MI than in those with type 1, discrepancies remain regarding this prognosis, possibly because of the different diagnostic criteria used.3–5 Nonetheless, there are no studies investigating the degree of acceptance of this classification or the extension of its use in clinical practice. Our aim was to evaluate the concordance between diagnosis associated with a troponin elevation in medical reports and diagnosis according to the universal definition of MI in patients with a positive troponin result and no acute coronary syndrome (ACS).

A retrospective study was carried out in a university hospital, including all consecutive patients admitted to the emergency department between January 2012 and December 2013 with at least 1 troponin determination. The exclusion criteria were as follows: troponin determination lower than the 99th percentile reference value, age younger than 18 years, patient recovering from cardiac arrest, patient with myocarditis, residence outside the hospital catchment area, and type 1 MI. Troponin determinations were all performed using the same immunoassay (Siemens Advia Centaur troponin I-Ultra; 99th percentile reference value 0.039 ng/mL and coefficient of variation < 10%). The diagnoses were categorized by consensus between 2 cardiologists: a) type 2 MI was established based on the criteria of Saaby et al.6 (who used a contemporary troponin assay having greater analytical imprecision than that used in our study), and b) myocardial injury without an ACS: patients with high troponin values who did not meet the criteria for type 2 MI. The study was approved by the local ethics committee. Patients were divided into 4 groups according to the department discharging them (cardiology, internal medicine, emergency, and others). The diagnoses associated with the troponin elevation in the discharge reports were classified into 5 categories: type 2 MI, myocardial injury without an SCA, secondary SCA, not specified, and others.

In total, 652 patients were included in the analysis. Baseline characteristics are shown in Table 1. Patients hospitalized in internal medicine had a history of chronic obstructive pulmonary disease more often. Dyspnea was the main symptom in patients hospitalized in cardiology and internal medicine, whereas atypical symptoms were more common in those hospitalized in other departments and in patients directly discharged from the emergency department. Of the 188 patients categorized as having type 2 MI, the discharge reports specified this diagnosis in only 6 patients (3.2%); of the 464 patients with myocardial injury, the discharge reports specified this diagnosis in only 11 (2.4%). The overall concordance between the categorization and the diagnosis recorded in the discharge reports was 2.61% (κ = 0.006; 95% confidence interval, –0.002 to 0.013). The results of the overall analysis and the analyses according to the department issuing the discharge report are shown in Table 2.

Table 1.

Patients’ Baseline Clinical Characteristics of the Patients According to the Department Issuing the Discharge Report

  Cardiology (n = 119)  Internal medicine (n = 105)  Others (n = 125)  Emergency (n = 303)  P 
Age, y  75 [63-81]  84 [75-88]  72 [59-81]  81 [72-85]  < .001 
Men  73 (61.34)  52 (49.52)  76 (60.80)  159 (52.48)  .128 
Myocardial infarction  29 (24.37)  21 (20.00)  30 (24.00)  80 (26.40)  .624 
Heart failure  19 (15.97)  21 (20.00)  16 (12.80)  63 (20.79)  .218 
Stroke or TIA  18 (15.13)  19 (18.10)  11 (8.80)  14 (15.51)  .200 
COPD  23 (19.33)  38 (36.19)  24 (19.20)  94 (31.02)  .003 
Diabetes  41 (34.45)  37 (35.24)  42 (33.60)  118 (38.94)  .677 
Hypertension  91 (76.47)  80 (76.19)  86 (68.80)  239 (78.88)  .175 
Chronic kidney disease  27 (22.69)  17 (16.19)  34 (27.20)  71 (23.43)  .257 
Charlson index  2 [1-3]  2 [1-4]  2 [0-4]  2 [1-4]  .255 
Symptoms
Chest pain  27 (22.69)  17 (16.19)  15 (12.00)  97 (32.01)  < .001 
Dyspnea  44 (36.97)  65 (61.90)  30 (24.00)  103 (33.99)  < .001 
Syncope  25 (21.01)  4 (3.81)  13 (10.40)  17 (5.61)  < .001 
Others  30 (25.21)  29 (27.62)  72 (57.60)  127 (41.91)  < .001 
Electrocardiogram*
Atrial fibrillation  36 (31.30)  34 (33.66)  21 (19.09)  114 (40.43)  .001 
Vital signs
HR, bpm  90 [67-117]  100 [81-112]  87 [73-109]  87.5 [69-113]  .126 
SAP, mmHg  134 [119-159]  129 [116-148]  134 [110-159]  134 [119-156]  .368 
SaO2, %  96 [93-98]  93 [89-96]  97 [92-99]  97 [94-99]  < .001 
Analytical determinations
eGFR, mL/min/1.73 m2  58.6 [40.2-78.0]  59.3 [39.0-80.2]  45.8 [19.8-82.3]  53.7 [41.0-74.1]  .021 
Hemoglobin, g/L  130 [109-140]  123 [110-134]  123 [98-139]  124 [112-140]  .282 
TnI maximum, ng/mL  0.25 [0.08-1.09]  0.12 [0.06-0.46]  0.14 [0.08-0.67]  0.09 [0.06-0.17]  < .001 

COPD chronic obstructive pulmonary disease; eGFR, estimated glomerular filtration rate; HR, heart rate; SAP, systolic arterial pressure; SaO2, arterial oxygen saturation; TIA, transient ischemic attack; TnI, troponin I

The data are expressed as No. (%) or median [interquartile range].

*

Electrocardiography data available for 115 patients admitted in cardiology, 101 admitted in internal medicine, 110 admitted in other departments, and 282 who were not admitted.

Table 2.

Analysis of Concordance Between the Diagnoses in the Discharge Reports and the Classification According to the Universal Definition of MI in the Overall Sample and by the Department Issuing the Report

Discharge diagnosesClassification according to the universal definition of MITotal
Type 2 MI  Myocardial injury without ACS 
Total of patients
Type 2 MI 
Myocardial injury without ACS  11  16 
Others  17  30  47 
Not specified  160  422  582 
Total  188  464  652 
Concordance, 2.61%; κ = 0.006 (95% CI, –0.002 to 0.013)       
Cardiology (n=119)
Type 2 MI 
Myocardial injury without ACS  10 
Others  12 
Not specified  45  47  92 
Concordance, 10.08%; κ = 0.039 (95% CI, 0.006-0.074)       
Internal medicine (n = 105)
Type 2 MI 
Myocardial injury without ACS 
Others 
Not specified  27  69  96 
Concordance, 1.90%; κ = 0.013 (95% CI, –0.005 to 0.031)       
Others (n = 125)
Type 2 MI 
Myocardial injury without ACS 
Others  11 
Not specified  32  81  113 
Concordance, 0.80%; κ = 0.002 (95% CI, –0.002 to 0.006)       
Emergency (n = 303)
Type 2 MI 
Myocardial injury without ACS 
Others  13  17 
Not specified  56  225  281 
Concordance, 0.66%; κ = –0.006 (95% CI, –0.015 to 0.002)       

95% CI, 95% confidence interval; ACS, acute coronary syndrome; MI, myocardial infarction

Our study performed in daily practice shows that a number of patients in the emergency department with a wide variety of clinical diagnoses have elevated troponin values. In these patients, diagnosis related to troponin elevation is specified in very few discharge reports, which indicates that acceptance of the terms type 2 MI and myocardial injury is lacking. In some cases, clinicians hesitate to assign a diagnosis of type 2 MI and, in contrast, “accept” a diagnosis of myocardial injury. There are several possible reasons for this finding. Physicians may avoid classifying patients as having type 2 MI or myocardial injury because of uncertainty that there is an underlying coronary disease. Or they may wish to avert treatments when there is scientific evidence of type 1 MI, but insufficient evidence to support treatment in the absence of a complicated atherothrombotic plaque. Another possible explanation is a lack of understanding of what actually constitutes type 2 MI. For type 2 MI and myocardial injury to be universally accepted, there should be broad consensus on the criteria to establish these diagnoses. This would enable standardization of research and identification of therapeutic strategies that could modify the prognosis. Perhaps when the evidence reaches this point, clinical acceptance of the terms included in the universal definition of MI will become more widely recognized. This study has the limitations of a single-center design and inclusion of patients with only 1 troponin determination, factors that may have had an impact on assigning some of the diagnoses.

.

References
[1]
A. Bardají, G. Cediel, A. Carrasquer, R. de Castro, R. Sánchez, C. Boqué.
Troponin Elevation in Patients Without Acute Coronary Syndrome.
Rev Esp Cardiol., 68 (2015), pp. 469-476
[2]
K. Thygesen, J.S. Alpert, H.D. White, et al.
Universal definition of myocardial infarction.
Circulation., 116 (2007), pp. 2634-2653
[3]
T. Nestelberger, J. Boeddinghaus, P. Badertscher, et al.
Effect of definition on incidence and prognosis of Type 2 myocardial infarction.
J Am Coll Cardiol., 70 (2017), pp. 1558-1568
[4]
N.R. Smilowitz, M.C. Weiss, R. Mauricio, et al.
Provoking conditions, management and outcomes of type 2 myocardial infarction and myocardial necrosis.
Int J Cardiol., 218 (2016), pp. 196-201
[5]
G. Cediel, M. Gonzalez-Del-Hoyo, A. Carrasquer, R. Sánchez, C. Boqué, A. Bardají.
Outcomes with type 2 myocardial infarction compared with non-ischaemic myocardial injury.
[6]
L. Saaby, T.S. Poulsen, S. Hosbond, et al.
Classification of myocardial infarction: frequency and features of type 2 myocardial infarction.
Am J Med., 126 (2013), pp. 789-797
Copyright © 2018. Sociedad Española de Cardiología
Idiomas
Revista Española de Cardiología (English Edition)

Subscribe to our newsletter

Article options
Tools
es en

¿Es usted profesional sanitario apto para prescribir o dispensar medicamentos?

Are you a health professional able to prescribe or dispense drugs?