Clinical OriginalThe universal classification is an independent predictor of long-term outcomes in acute myocardial infarction
Introduction
The universal classification (UC) of acute myocardial infarction (AMI) aims to facilitate cross-study analysis and interpretation with emphasis on cardiac troponin (cTn) as the preferred biomarker [1]. The UC groups the AMI according to clinical and pathophysiologic characteristics in Types 1 to 5, as described in the Methods section (Fig. 1). However, it is unknown whether the long-term outcomes of AMI patients are different using the UC compared to the traditional electrocardiographic (ECG) based ST-segment classification (STC).
Section snippets
Study population
This is a retrospective cohort study of 348 consecutive patients from a single tertiary hospital with a discharge diagnosis of AMI from December 31, 2004, until December 31, 2006, who met the study criteria. Patients were followed for a minimum of 24 months for clinical outcomes until December 31, 2007. We performed a retrospective classification of AMI based on the 2007 Universal Definition consensus document [1].
Inclusion and exclusion criteria
We included male and female patients, age >30 years old, who met the UC criteria
Baseline characteristics
The study population consisted of 348 patients with AMI, including STEMI=168 (48.3%), NSTEMI=180 (51.7%), Type 1=278 (79.9%), Type 2=55 (15.8%), Type 3=5 (1.4%), Type 4a=2 (0.6%), Type 4b=5 (1.4%), and Type 5=3 (0.9%). The underlying etiology of patients with Type 2 AMI included coronary artery spasm=3 (5.4%), coronary embolism=1 (1.8%), anemia=18 (32.7%), arrhythmias=9 (16.4%), hypertension=23 (41.8%), hypotension=6 (10.9%), and more than one cause=5 (9%). The general demographic, clinical,
Discussion
We observed a lower incidence of Type 1 AMI (79.9% vs. 88.5%) but a higher incidence of Type 2 (15.8% vs. 1.6%) compared to rates reported by Melberg et al. [4]. Patients with Type 1 AMI have more than twice the risk of MACE than Type 2 patients despite having similar rates of CVRF, CAD, PVD, ejection fraction (EF), three-vessel CAD, and receiving similar CVPM at discharge. The significant differences at baseline between Type 1 and Type 2 patients are higher peak CK, CK-MB, and cTn levels. This
Limitations
This is a retrospective cohort study of 348 patients with AMI admitted to a single tertiary hospital with potential for selection, referral, and overrepresentation bias. Therefore, the results may not be directly generalizable to other regions. Second, we performed a retrospective definition of AMI based on the 2007 UC consensus document, which may be a source of misclassification bias despite our best efforts to minimize it. Third, we could have underestimated the rate of all causes of death
Conclusion
This is the first study to demonstrate that the UC is an independent predictor and has better discrimination of long-term outcomes of patients with AMI compared to the STC. Type 2 AMI has less than half the risk of MACE as Type 1 AMI at 30.6 months of follow-up. The UC, peak cTn levels, discharge GFR <60, and TIMI risk score are independent predictors of MACE and all causes of death. In contrast, the STC and peak MB levels are independent predictors of recurrent nonfatal AMI. Future studies
References (9)
- et al.
Twenty-two year (1975 to 1997) trends in the incidence, in-hospital and long-term case fatality rates from initial Q-wave and non-Q-wave myocardial infarction: a multi-hospital, community-wide perspective
J Am Coll Cardiol
(2001) - et al.
The prognosis of a first Q-wave versus non-Q-wave myocardial infarction in the reperfusion era
Am J Med
(2000) - et al.
Universal definition of myocardial infarction
Circulation
(2007) - et al.
ACC/AHA 2007 guidelines for the management of patients with unstable angina/non ST-elevation myocardial infarction: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines for the Management of Patients With Unstable Angina/Non ST-Elevation Myocardial Infarction): developed in collaboration with the American College of Emergency Physicians, the Society for Cardiovascular Angiography and Interventions, and the Society of Thoracic Surgeons: endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation and the Society for Academic Emergency Medicine
Circulation
(2007)
Cited by (15)
Type 2 myocardial infarction
2023, Annales de Cardiologie et d'AngeiologieMeta-analysis Comparing Outcomes of Type 2 Myocardial Infarction and Type 1 Myocardial Infarction With a Focus on Dual Antiplatelet Therapy
2020, CJC OpenCitation Excerpt :We retrieved 2048 citations of studies of T2MI and 1669 citations of studies evaluating DAPT in ACS (Fig. 1). For the final evaluation, we retained 19 cohorts enrolling 48,829 patients (43,468 with T1MI and 5361 with T2MI)8-27 (Table 1) and 51 RCTs enrolling 188,132 patients25-77 (Fig. 1). We described the characteristics of the patients enrolled in the observational studies in Supplemental Table S1.
The Reply
2017, American Journal of MedicineFrequency of myocardial infarction according to the third universal definition
2017, Revista Colombiana de CardiologiaType 2 Myocardial Infarction and Long-Term Mortality Risk Factors: A Retrospective Cohort Study
2023, Advances in TherapyCardiovascular outcomes of type 2 myocardial infarction among COVID-19 patients: a propensity matched national study
2023, Expert Review of Cardiovascular Therapy