PROGNOSTIC FACTORS IN PATIENTS WITH MYOCARDIAL INFARCTION WITH ST ELEVATION AT 12 HOURS AFTER THE ACUTE EVENT
Received for publication: 11th of November, 2013
Revised: 26th of November, 2013
SUMMARY: (Hide the summary)
The patients with ST-elevation myocardial infarction (STEMI) are at increased risk of major cardiovascular events, especially death. In these patients, early risk stratification plays a central role, as the benefits of the modern techniques seem to be proportional to the risk of adverse effects. Although percutaneous angioplasty has significantly improved the outcome of these patients compared to fibrinolytic treatment, high-risk patients still have high mortality and morbidity rates. Our study consisted was retrospective and consisted in the analysis of 165 patients’ charts admitted in the Cardiovascular Disease Institute between 2009 and 2012 with acute myocardial infarction with symptoms onset more than 12 hours upon admission which underwent PTCA. We analyzed as primary end-points end-diastolic volume and ejection fraction, and as secondary end-points mortality, reinfarction rate, NYHA IV cardiac failure and intrasent thrombosis rate. The aim of the study was to determine the predictive factors in ST-myocardial infarction patients that underwent primary angioplasty after 12 hours of the symptoms onset.
infarct miocardic, angioplastie, fibrinoliză.
The superiority of primary percutaneous angioplasty over fibrinolysis has been demonstrated in several studies.(1-3) It has been observed that the benefit of primary angioplasty is different in each group of patients and the benefit is greatest in those at high risk. Thus, the stratification prior to intervention has great clinical importance to identify this group of patients at higher risk and to optimize their therapeutic management.
We analyzed as primary end-points end-diastolic volume and ejection fraction, and as secondary end-points mortality, reinfarction rate, NYHA IV cardiac failure and intrasent thrombosis rate. The aim of the study was to determine the predictive factors in ST-myocardial infarction patients that underwent primary angioplasty after 12 hours of the symptoms onset.
MATERIAL AND METHODS
The studied sample consisted of 165 patients admitted for acute myocardial infarction with symptom onset for more than 12 hours upon admission in the Cardiology Department, Cardiovascular Disease Institute Timisoara from 2009 until 2013. The studied parameters were recorded at the time of the procedures, at 1 and at 3 months after that.
Including criteria were symptoms onset more than 12 hours upon admission and ST segment elevation for more than 2 mm in at least 2 ECG derivations.
Excluding criteria were left bundle branch block, coronary trunk stenosis with surgical indication, triple artery involvement, mechanical ventilation upon admission, past CABG procedures, usage of thrombus aspiration catheter.
Primary endpoints are telediastolic volume (VTD) and ejection fraction (FE). Secondary endpoints are mortality rate, reinfarction rate, NYHA IV cardiac insufficiency and intrastent thrombosis. We calculated for the studied sample the TIMI risk score (Table 1.).
Table 1. TIMI risk score for STEMI.
Statistical analysis was performed with SPSS 13.0 software.
RESULTS AND DISCUSSIONS
The patients’ demographic data are presented in table 2.
Table 2. Demographic data for the studied sample.
Current sample consisted of 165 patients with ST-supradenivelation myocardial infarction.
We analyzed the TIMI score for these patients. The TIMI score is a simple prognostication scheme that categorizes a patient’s risk of death and ischemic events and provides a basis for therapeutic decision making.(4) Score interpretation is the risk percentage at 14 days: all-cause mortality, new or recurrent myocardial infarction or severe ischemia requiring urgent revascularization. (4)
Score interpretation is, as follows: score of 0 – 1 = 4.7% risk, score of 2 = 8.3% risk, score of 3 = 13.2% risk, score of 4 = 19.9% risk, score of 5 = 26.2% risk, score of 6-7 = 40.9% risk.
We also believe that the TIMI score applied to these patients without cardiogenic shock who undergo primary angioplasty predicts in-hospital mortality.
From the studied sample, 44.84% of patients were having diabetes mellitus, 81.81% arterial hypertension, 53.93 were included in Killip class II-III. The mean ejection fraction measured by echocardiography was 45.74 +/- 10.2% and 6.06% of patients were having an ejection fraction under 35%. The distribution of patients according to TIMI score is listed in the next table.
Table 3. Clinical presentation and coronary artery involvement
Table 4. In-hospital endpoints
Table 5.TIMI risk score for the studied sample.
Table 6. TIMI score distribution.
Table 7. In hospital mortality and adverse effects.
The in-hospital mortality was 3.03%, all patients having a TIMI score above 8. We considered a low risk patient with a TIMI score under 5 (120 patients – 72.72%) and a high risk patient with a TIMI score above 5 (45 patients – 27.27%). The TIMI score was a very good predictor for in-hospital mortality (p < 0.01). Lev et al.(5) reported that stratification with TIMI score in patients undergoing primary angioplasty is a good predictor of mortality and major adverse cardiac events (myocardial infarction, death).
We are aware that TIMI score was developed to predict mortality, but it also identifies a group of high-risk patients (a score above 5), who have an increased frequency of adverse effects, such as heart failure or ventricular arrhythmias.
We applied the TIMI score in STEMI patients, undergoing primary angioplasty. This score predicted not only in-hospital mortality, but other adverse effects such as stroke, or ventricular arrhythmias, reinfarction rate or heart failure.
- Van de Werf F, Ardissino D, Betriu A, et al. Management of acute myocardial infarction in patients presenting with ST-segment elevation. Eur Heart J 2003;24:28–66.
- Fibrinolytic Therapy Trialists’ (FTT) Collaborative Group. Indications for fibrinolytic therapy in suspected acute myocardial infarction: collaborative overview of early mortality and major morbidity results from all randomized trials of more than 1000 patients. Lancet 1994;343:311–322.
- Keeley EC, Boura JA, Grines CL. Primary angioplasty versus intravenous thrombolytic therapy for acute myocardial infarction: a quantitative review of 23 randomised trials. Lancet 2003; 361:13– 20.
- Elliott M. Antman, MD; Marc Cohen, MD; Peter J. L. M. Bernink, MD; Carolyn H. McCabe, BS; Thomas Horacek,MD, The TIMI Risk Score for Unstable Angina/NonST Elevation MI", JAMA, 2000.
- Lev EI, Kornowski R, Vaknin-Assa H, et al. Comparison of the predictive value of four different risk scores for outcomes of patients with ST-elevation acute myocardial infarction undergoing primary percutaneous coronary intervention. Am J Cardiol 2008; 102:6–11.