Application of the Thrombolysis in Myocardial Infarction risk index in non-ST-segment elevation myocardial infarction: evaluation of patients in the National Registry of Myocardial Infarction.

OBJECTIVES: The purpose of this research was to evaluate the Thrombolysis In Myocardial Infarction risk index (TRI) to characterize the risk of death among patients with non-ST-segment elevation myocardial infarction (NSTEMI). BACKGROUND: The TRI, calculated from baseline age, systolic pressure, and heart rate, was established in patients with ST-segment elevation myocardial infarction (STEMI) and is predictive of mortality. Patients presenting with NSTEMI are increasing compared to STEMI and constitute a group with varied risk. METHODS: The TRI was calculated in 337,192 patients from the National Registry of Myocardial Infarction with NSTEMI. Values and outcomes were compared with 153,486 patients with STEMI classified by reperfusion status. Comparisons of baseline characteristics and clinical outcomes stratified by TRI were made. RESULTS: There was a graded relationship between the TRI and mortality in patients with NSTEMI with a >30-fold difference in mortality rates between lowest and highest deciles (p < 0.0001). The index showed good discrimination (c = 0.73). Overall mortality in the group with NSTEMI was higher (10.9%) than patients with STEMI treated with (6.6%) but lower than for STEMI patients not receiving reperfusion therapy (18.7%). The higher risk in comparison to patients with STEMI treated with reperfusion therapy was explained largely by the higher-risk profile of the population with NSTEMI. CONCLUSIONS: There is a graded relationship between TRI and mortality in patients with NSTEMI. This simple risk index provides important information about mortality in patients across the spectrum of myocardial infarction, STEMI and NSTEMI. Early identification of NSTEMI patients who are at high risk of in-hospital mortality may provide clinicians with important information for initial triage and treatment.     

B-type natriuretic peptide at presentation and prognosis in patients with ST-segment elevation myocardial infarction: an ENTIRE-TIMI-23 substudy

OBJECTIVES: We sought to evaluate B-type natriuretic peptide (BNP), alone and in comparison to cardiac troponin I (cTnI) and high-sensitivity C-reactive protein (hs-CRP), for risk assessment at initial presentation with ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Elevated levels of BNP drawn two to four days after acute myocardial infarction are associated with higher mortality. Sparse data are available on its use at first presentation with STEMI. METHODS: We obtained samples from 438 patients presenting within 6 h of STEMI enrolled in the Enoxaparin Tenecteplase-Tissue-Type Plasminogen Activator With or Without Glycoprotein IIb/IIIa Inhibitor as Reperfusion Strategy in ST-Segment Elevation Myocardial Infarction (ENTIRE)-Thrombolysis In Myocardial Infarction (TIMI)-23 trial. Outcomes were assessed through 30 days. RESULTS: Median BNP was higher in patients who died (89 pg/ml, 25th to 75th percentile: 40 to 192), compared with survivors (15 pg/ml, 25th to 75th percentile: 8.8 to 32, p < 0.0001). Patients with BNP >80 pg/ml were at significantly higher risk of death (17.4% vs. 1.8%, p < 0.0001). Cardiac troponin established a gradient of mortality between the highest and lowest quartile (7.9% vs. 0%, p = 0.007). C-reactive protein was not associated with outcome. After adjustment for cTnI, hs-CRP, and major clinical predictors, including age, heart failure, anterior myocardial infarction location, heart rate, and blood pressure, a BNP level >80 pg/ml was associated with a seven-fold higher mortality risk (odds ratio 7.2, 95% confidence interval 2.1 to 24.5, p = 0.001). Patients with BNP >80 pg/ml were also more likely to have impaired coronary flow (p = 0.049) and incomplete resolution of ST-segment elevation (p = 0.05). CONCLUSIONS: Increased concentrations of BNP at initial presentation of patients with STEMI are associated with impaired reperfusion after fibrinolysis and higher short-term risk of mortality. These data support the value of combining markers of hemodynamic stress with traditional approaches to risk assessment in acute myocardial infarction.     

Comparative early and late outcomes after primary percutaneous coronary intervention in ST-segment elevation and non-ST-segment elevation acute myocardial infarction (from the CADILLAC trial)

We determined the outcomes of patients with acute ST-segment elevation (STE) myocardial infarction (STEMI) and non-STEMI (NSTEMI) after primary percutaneous coronary intervention (PCI). The prognosis after primary PCI in STEMI has been extensively studied and defined. Outcomes of patients who undergo primary PCI for NSTEMI are less well established. In total, 2,082 patients with ongoing chest pain for > 30 minutes consistent with acute MI were randomized to balloon angioplasty versus stenting, each with/without abciximab. Of 1,964 patients, STEMI was present in 1,725 (87.8%) and NSTEMI in 239 (12.2%). Compared with STEMI, those with NSTEMI were more likely to have delayed time-to-hospital arrival (2.4 vs 1.8 hours, p = 0.0002) and increased door-to-balloon time (3.2 vs 1.9 hours, p < 0.0001). Patients with NSTEMI were more likely to have Thrombolysis In Myocardial Infarction grade 3 flow at baseline (37.3% vs 19.4%, p < 0.0001) and higher ejection fraction (58.7% vs 55.8%, p = 0.001), but similar rates of postprocedural Thrombolysis In Myocardial Infarction grade 3 flow. At 1 year, patients with NTEMI had similar mortality (3.4% vs 4.4%, p = 0.40) but higher rates of major adverse cardiac events (24.0% vs 16.6%, p = 0.007) that was driven by more frequent ischemic target vessel revascularization (21.8% vs 11.9%, p <0.0001). In conclusion, patients with acute MI without STE who are treated with primary PCI have marked delays to treatment, similar late mortality, and increased rates of ischemic target vessel revascularization compared with patients with STEMI, despite more favorable angiographic features at presentation and similar reperfusion success. The adverse prognosis of patients with NSTEMI should be recognized and efforts made to decrease reperfusion times.     

Diabetes mellitus, myocardial reperfusion, and outcome in patients with acute ST-elevation myocardial infarction treated with primary angioplasty (from HORIZONS AMI)

Diabetes mellitus (DM) increases mortality in acute ST-segment elevation myocardial infarction (STEMI) but the responsible mechanism is not fully elucidated. We compared the rate of successful myocardial reperfusion measured by tissue myocardial perfusion grade (TMPG) and outcomes in patients with and without DM undergoing primary percutaneous coronary intervention (PCI) for STEMI. Patients enrolled in the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS AMI) trial were analyzed according to presence of DM with respect to TMPG after PCI and outcomes at 30 days and 3 years. Multivariable logistic regression was performed to identify the independent contribution to mortality of DM and TMPG and the interaction between the 2 was assessed. Complete data were available for 3,265 patients, of whom 533 (16.3%) had DM. Diabetic patients were significantly older and heavier and had more risk factors for coronary disease and more previous MI, revascularization, and heart failure. There were no differences in rates of Thrombolysis In Myocardial Infarction grade 3 flow after PCI in the infarct artery or TMPG 2/3 between patients with and without DM. Compared to nondiabetics, mortality was significantly higher at 30 days and at 3 years in the DM group (1.8% vs 4.5%, p = 0.0002 and 5.4% vs 11.0%, p <0.0001, respectively). DM and TMPG were significantly associated with 3-year mortality, but there was no statistical interaction between DM and TMPG (p = 0.70). In conclusion, DM is associated with a significantly higher risk of death but this association is not mediated by impaired epicardial or myocardial reperfusion.     

Validation of the Thrombolysis In Myocardial Infarction (TIMI) risk index for predicting early mortality in a population-based cohort of STEMI and non-STEMI patients

BACKGROUND: The Thrombolysis In Myocardial Infarction (TIMI) risk index for the prediction of 30-day mortality was developed and validated in patients with ST-segment elevation myocardial infarction (STEMI) who were being treated with thrombolytics in randomized clinical trials. When tested in clinical registries of patients with STEMI, the index performed poorly in an older (65 years and older) Medicare population, but it was a good predictor of early death among the more representative population on the National Registry of Myocardial Infarction-3 and -4 databases. It has not been tested in a population outside the United States or among non-STEMI patients. METHODS: The TIMI risk index was applied to the Enhanced Feedback for Effective Cardiac Treatment (EFFECT) study cohort of 11,510 acute MI patients from Ontario. The model's discriminatory capacity and calibration were tested in all patients and in subgroups determined by age, sex, diagnosis and reperfusion status. RESULTS: The TIMI risk index was strongly associated with 30-day mortality for both STEMI and non-STEMI patients. The C statistic was 0.82 for STEMI and 0.80 for non-STEMI patients, with overlapping 95% CI. The discriminatory capacity was somewhat lower for patients older than 65 years of age (0.74). The model was well calibrated. CONCLUSIONS: The TIMI risk index is a simple, valid and moderately accurate tool for the stratification of risk for early death in STEMI and non-STEMI patients in the community setting. Its routine clinical use is warranted.     

Mean platelet volume on admission predicts impaired reperfusion and long-term mortality in acute myocardial infarction treated with primary percutaneous coronary intervention

OBJECTIVES: We sought to determine the prognostic value of mean platelet volume (MPV) for angiographic reperfusion and six-month mortality in patients with acute ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). BACKGROUND: Mean platelet volume is predictive of unfavorable outcome among survivors of STEMI when measured after the index event. No data are available for the value of admission MPV in patients with STEMI treated with primary PCI. METHODS: Blood samples for MPV estimation, obtained on admission in 398 consecutive patients presenting with STEMI, were measured before primary PCI. Follow-up up to six months was performed. RESULTS: No-reflow was significantly more frequent in patients with high MPV (> or =10.3 fl) compared with those with low MPV (<10.3 fl) (21.2% vs. 5.5%, p < 0.0001). The MPV was correlated strongly with corrected Thrombolysis In Myocardial Infarction frame count (CTFC) (r = 0.698, p < 0.0001). Kaplan-Meier survival analysis showed six-month mortality rate of 12.1% in patients with high MPV versus 5.1% in low MPV group (log rank = 6.235, p = 0.0125). After adjusting for baseline characteristics, high MPV remained a strong independent predictor of no-reflow (odds ratio [OR] 4.7, 95% confidence interval [CI] 2.3 to 9.9, p < 0.0001), CTFC > or =40 (OR 10.1, 95% CI 5.7 to 18.1, p < 0.0001), and mortality (OR 3.2, 95% CI 1.1 to 9.3, p = 0.0084). Abciximab administration resulted in significant mortality reduction only in patients with high MPV values (OR 0.02, 95% CI 0.01 to 0.48, p = 0.0165). CONCLUSIONS: Mean platelet volume is a strong, independent predictor of impaired angiographic reperfusion and six-month mortality in STEMI treated with primary PCI. Apart from prognostic value, admission MPV may also carry further practical, therapeutic implications.     

Treatment and outcome of myocardial infarction in hospitals with and without invasive capability. Investigators in the National Registry of Myocardial Infarction

OBJECTIVES: We sought to determine the extent to which the capability of a hospital to perform invasive cardiovascular procedures influences treatment and outcome of patients admitted with acute myocardial infarction (AMI). BACKGROUND: Patients with AMI are usually transported to the closest hospital. However, relatively few hospitals have the capability for immediate coronary arteriography, percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass graft surgery (CABG), should these interventions be needed. METHODS: The 1,506 hospitals participating in the National Registry of Myocardial Infarction 2 were classified according to their highest level of invasive capability: 1) none (noninvasive, 28.1%); 2) coronary arteriography (cath-capable, 25.2%); 3) coronary angioplasty (PTCA-capable, 7.4%); and 4) bypass surgery (CABG-capable, 39.2%). Treatment and in-hospital outcomes were assessed for 305,812 patients admitted from June 1994 through October 1996. Follow-up through 90 days was ascertained in a subset of 30,402 patients enrolled simultaneously in both the National Registry of Myocardial Infarction (NRMI) 2 and the Cooperative Cardiovascular Project (CCP). RESULTS: The proportion of patients receiving initial reperfusion intervention was only slightly higher at the more invasive hospitals (noninvasive 32.5%, cath-capable 31.2%, PTCA-capable 32.9% and CABG-capable 35.9%, p < 0.001 by chi-square statistic). Among thrombolytic recipients, median door-to-drug time interval differed little among hospital types and ranged from 42 to 45 minutes. At cath-capable, PTCA-capable and CABG-capable hospitals, coronary arteriography was performed in 32.9%, 37.4% and 64.9%, respectively, and PTCA in 0.0%, 5.1% and 31.4%, both p < 0.001 by chi-square statistic. The proportion of patients transferred out to other facilities was 51.0%, 42.2%, 39.9% and 4.4% (p < 0.0001) among noninvasive, cath-capable, PTCA-capable and CABG-capable hospitals, respectively. Among patients in the combined NRMI and CCP data set, mortality at 90 days postinfarction was similar among patients initially admitted to each of the four hospital types. CONCLUSIONS: Although patients with AMI admitted to hospitals without invasive cardiac facilities have a high likelihood of subsequent transfer to other facilities, their likelihood of receiving a reperfusion intervention at the first hospital, their door to thrombolytic drug intervals and their 90-day survival rates are similar to those of patients initially admitted to more invasively equipped hospitals. These data suggest that a policy of initial treatment of myocardial infarction at the closest medical facility is appropriate medical practice.     

Comparison of bleeding and in-hospital mortality in Asian-Americans versus Caucasian-Americans with ST-elevation myocardial infarction receiving reperfusion therapy

Concern has been raised that Asian-Americans may have a higher bleeding risk than Caucasian-Americans when treated with fibrinolytic and antithrombotic agents. To date there is limited evidence to support or refute this hypothesis or evaluate bleeding risk and its related outcomes in Caucasian-Americans versus Asian-Americans with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary interventions (PPCI). We evaluated Asian-Americans and Caucasian-Americans with STEMI receiving reperfusion therapy in the National Registry of Myocardial Infarction (NRMI) 4 and 5 (n = 90,317). We studied risk-adjusted major bleeding and in-hospital mortality. Major bleeding rates after fibrinolysis were similar in Asian-Americans (n = 705) and Caucasian-Americans (n = 42,243, 11.1% vs 10.3%, adjusted odds ratio [OR] 0.97, 95% confidence interval [CI] 0.69 to 1.36, p = 0.5002). Although the observed major bleeding rate was higher in Asian-Americans (n = 1,037) compared to Caucasian-Americans (n = 46,332) treated with PPCI (10.3% vs 7.8%, p = 0.0036), these rates differed only marginally after adjusting for baseline clinical variables (OR 1.24, 95% CI 0.97 to 1.59). Overall adjusted mortality was similar in Asian-Americans and Caucasian-Americans when treated with fibrinolysis (OR 0.96, 95% CI 0.56 to 1.65) or with PPCI (OR 1.35, 95% CI 0.85 to 2.13). Major bleeding after PPCI or fibrinolysis was associated with similar increased risks for mortality in these ethic groups. In conclusion, despite suggestions to the contrary, Asian-Americans with STEMI treated with fibrinolysis or PPCI had similar bleeding and bleeding-related mortality risks compared to Caucasian-Americans. Given the genotypic and phenotypic differences between the 2 cohorts, similar studies in the rapidly growing Asian-American population are needed to confirm our findings and to understand the safety and effectiveness of newer potent antiplatelet and antithrombotic agents in patients with coronary syndromes.     

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

Accurate risk stratification has an important role in the management of patients with acute coronary syndromes. Even in patients with ST-elevation acute myocardial infarction (STEMI), for whom early therapeutic options are well defined, risk stratification has an impact on early and late therapeutic decision making. We aimed to compare the prognostic value of 4 risk scores used to evaluate patients with STEMI. We conducted a prospective registry of all patients treated with primary percutaneous coronary intervention for STEMI from January 2001 to June 2006. Excluded were patients with cardiogenic shock. A total of 855 consecutive patients were included in the analysis (age 60.5 +/- 13 years, 19% women, 28% with diabetes, and 48% with anterior wall myocardial infarction). For each patient, the Thrombolysis In Myocardial Infarction (TIMI), Controlled Abciximab and Device Investigation to Lower Late Angioplasty complications (CADILLAC), Primary Angioplasty in Myocardial Infarction (PAMI), and Global Registry for Acute Coronary Events (GRACE) risk scores were calculated using specific clinical variables and angiographic characteristics. Thirty-day and 1-year clinical outcomes were assessed. The predictive accuracy of the 4 risk scores was evaluated using the area under the curve or C statistic method. The CADILLAC, TIMI, and PAMI risk scores all had relatively high predictive accuracy for 30-day and 1-year mortality (C statistic range 0.72 to 0.82), with slight superiority of the CADILLAC score. These 3 risk scores also performed well for prediction of reinfarction at 30 days (C statistic range 0.6 to 0.7). The GRACE score did not perform as well and had low predictive accuracy for mortality (C statistic 0.47). In conclusion, risk stratification of patients with STEMI undergoing primary percutaneous coronary intervention using the CADILLAC, TIMI, or PAMI risk scores provide important prognostic information and enables accurate identification of high-risk patients.     

Effect of door-to-balloon time on mortality in patients with ST-segment elevation myocardial infarction.

OBJECTIVES: We sought to determine the effect of door-to-balloon time on mortality for patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). BACKGROUND: Studies have found conflicting results regarding this relationship. METHODS: We conducted a cohort study of 29,222 STEMI patients treated with PCI within 6 h of presentation at 395 hospitals that participated in the National Registry of Myocardial Infarction (NRMI)-3 and -4 from 1999 to 2002. We used hierarchical models to evaluate the effect of door-to-balloon time on in-hospital mortality adjusted for patient characteristics in the entire cohort and in different subgroups of patients based on symptom onset-to-door time and baseline risk status. RESULTS: Longer door-to-balloon time was associated with increased in-hospital mortality (mortality rate of 3.0%, 4.2%, 5.7%, and 7.4% for door-to-balloon times of < or =90 min, 91 to 120 min, 121 to 150 min, and >150 min, respectively; p for trend <0.01). Adjusted for patient characteristics, patients with door-to-balloon time >90 min had increased mortality (odds ratio 1.42; 95% confidence interval [CI] 1.24 to 1.62) compared with those who had door-to-balloon time < or =90 min. In subgroup analyses, increasing mortality with increasing door-to-balloon time was seen regardless of symptom onset-to-door time (< or =1 h, >1 to 2 h, >2 h) and regardless of the presence or absence of high-risk factors. CONCLUSIONS: Time to primary PCI is strongly associated with mortality risk and is important regardless of time from symptom onset to presentation and regardless of baseline risk of mortality. Efforts to shorten door-to-balloon time should apply to all patients.     

Thrombus aspiration before primary angioplasty improves myocardial reperfusion in acute myocardial infarction: the DEAR-MI (Dethrombosis to Enhance Acute Reperfusion in Myocardial Infarction) study.

OBJECTIVES: This study sought to test the hypothesis that thrombus removal, with a new manual thrombus-aspirating device, before primary percutaneous coronary intervention (PPCI) may improve myocardial reperfusion compared with standard PPCI in patients with ST-segment elevation acute myocardial infarction (STEMI). BACKGROUND: In STEMI patients, PPCI may cause thrombus dislodgment and impaired microcirculatory reperfusion. Controversial results have been reported with different systems of distal protection or thrombus removal. METHODS: One-hundred forty-eight consecutive STEMI patients, admitted within 12 h of symptom onset and scheduled for PPCI, were randomly assigned to PPCI (group 1) or manual thrombus aspiration before standard PPCI (group 2). Patients with cardiogenic shock, previous infarction, or thrombolytic therapy were excluded. Primary end points were complete (>70%) ST-segment resolution (STR) and myocardial blush grade (MBG) 3. RESULTS: Baseline clinical and angiographic characteristics were similar in the 2 groups. Comparing groups 1 and 2: complete STR 50% versus 68% (p < 0.05); MBG-3 44% versus 88% (p < 0.0001); coronary Thrombolysis In Myocardial Infarction (TIMI) flow grade 3 78% versus 89% (p = NS); corrected TIMI frame count 21.5 +/- 12 versus 17.3 +/- 6 (p < 0.01); no reflow 15% versus 3% (p < 0.05); angiographic embolization 19% versus 5% (p < 0.05); direct stenting 24% versus 70% (p < 0.0001); and peak creatine kinase-mass band fraction 910 +/- 128 mug/l versus 790 +/- 132 mug/l (p < 0001). In-hospital clinical events were similar in the 2 groups. After adjusting for confounding factors, multivariate analysis showed thrombus aspiration to be an independent predictor of complete STR and MBG-3. CONCLUSIONS: Manual thrombus aspiration before PPCI leads to better myocardial reperfusion and is associated with lower creatine kinase mass band fraction release, lower risk of distal embolization, and no reflow compared with standard PPCI. (Thrombus Aspiration Before Standard Primary Angioplasty Improves Myocardial Reperfusion in Acute Myocardial Infarction; http://clinicaltrials.gov/ct/show/NCT00257153).     

Impact of delay in door-to-needle time on mortality in patients with ST-segment elevation myocardial infarction

Fibrinolytic therapy is the most common reperfusion strategy for patients with ST-segment elevation myocardial infarction (STEMI), particularly in smaller centers. Previous studies evaluated the relation between time to treatment and outcomes when few patients were treated within 30 minutes of hospital arrival and many did not receive modern adjunctive medications. To quantify the impact of a delay in door-to-needle time on mortality in a recent and representative cohort of patients with STEMI, a cohort of 62,470 patients with STEMI treated using fibrinolytic therapy at 973 hospitals that participated in the National Registry of Myocardial Infarction from 1999 to 2002 was analyzed. Hierarchical models were used to evaluate the independent effect of door-to-needle time on in-hospital mortality. In-hospital mortality was lower with shorter door-to-needle times (2.9% for < or =30 minutes, 4.1% for 31 to 45 minutes, and 6.2% for >45 minutes; p <0.001 for trend). Compared with those experiencing door-to-needle times < or =30 minutes, adjusted odd ratios (ORs) of dying were 1.17 (95% confidence interval [CI] 1.04 to 1.31) and 1.37 (95% CI 1.23 to 1.52; p for trend <0.001) for patients with door-to-needle times of 31 to 45 and >45 minutes, respectively. This relation was particularly pronounced in those presenting within 1 hour of symptom onset to presentation time (OR 1.25, 95% CI 1.01 to 1.54; OR 1.54, 95% CI 1.27 to 1.87, respectively; p for trend <0.001). In conclusion, timely administration of fibrinolytic therapy continues to significantly impact on mortality in the modern era, particularly in patients presenting early after symptom onset.     

Thrombolysis in myocardial infarction myocardial perfusion grade in angiography correlates with myocardial salvage in patients with acute myocardial infarction treated with stenting or thrombolysis

OBJECTIVES: We sought to assess the relationship between the Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion (TMP) grade and myocardial salvage as well as the usefulness of TMP grade in comparing two different reperfusion strategies. BACKGROUND: The angiographic index of TMP grade correlates with infarct size and mortality after thrombolysis for acute myocardial infarction (AMI). Its relationship to myocardial salvage and its usefulness in comparing different reperfusion strategies are not known. METHODS: We analyzed the TMP grade on angiograms obtained at one to two weeks after treatment in 267 patients enrolled in two randomized trials that compared stenting with thrombolysis in AMI. Patients were classified into two groups: 159 patients with TMP grade 2/3 and 108 patients with TMP grade 0/1. Two scintigraphic studies were performed: before and one to two weeks after reperfusion. The salvage index was calculated as the proportion of the area at risk salvaged by reperfusion. RESULTS: Patients with TMP grade 2/3 had a higher salvage index (0.49 +/- 0.42 vs. 0.34 +/- 0.49, p = 0.01), a smaller final infarct size (15.4 +/- 15.5% vs. 22.1 +/- 16.2% of the left ventricle, p = 0.001), and a trend toward lower one-year mortality (3.8% vs. 8.3%, p = 0.11) than patients with TMP grade 0/1. The relationship between TMP and salvage index was independent of the form of reperfusion therapy. The proportion of patients with TMP grade 2/3 was significantly higher after stenting than after thrombolysis (70.9% vs. 48.1%, p = 0.001). CONCLUSIONS: These findings show that the TMP grade is a useful marker of the degree of myocardial salvage achieved with reperfusion and a sensitive indicator of the efficacy of reperfusion strategies in patients with AMI.     

The Risk Score Profile: a novel approach to characterising the risk of populations enrolled in clinical studies.

AIMS: Interpreting the results and practice implications of clinical studies requires accurate characterisation of the baseline risk of the population. We evaluated the Thrombolysis in Myocardial Infarction (TIMI) risk score for STEMI as a tool to describe and compare the risk profile of populations enrolled in three clinical trials (InTIME-II, ASSENT-2 and MAGIC) and the National Registry of Myocardial Infarction. METHODS AND RESULTS: The risk score was calculated for each patient (N=121,085) and the frequency distribution plotted for each population. The Risk Score Profiles were compared using the Kolmogorov-Smirnov test. The Risk Score Profile demonstrated a striking concordance between the baseline risk of patients in InTIME-II and ASSENT-2 (median scores in each= 3[1,4], P=0.11). In contrast, the distributions in MAGIC (designed to enroll high risk) and NRMI (registry) were shifted significantly toward higher risk (median scores=4[3,5] for MAGIC and 4[2,6] in NRMI, P < 0.0001 for each vs. InTIME-II). A graded relationship between the risk score and mortality was evident in each study (P<0.0001). CONCLUSIONS: The frequency distribution of the TIMI Risk Score, or similar tools for risk assessment, may be used to quantify and readily compare the risk profile of populations enrolled in clinical studies.     

Effectiveness of primary percutaneous coronary intervention for acute ST-elevation myocardial infarction from a 5-year single-center experience

Primary percutaneous coronary intervention (PCI) is currently viewed as the preferred reperfusion strategy in patients with ST-elevation acute myocardial infarction (STEMI). This method was introduced in our hospital in 2000. From January 1, 2000, to December 31, 2004, a total of 2,393 consecutive patients with STEMI were admitted (27% transferred from 9 non-PCI hospitals and 31 prehospital emergency units/outpatient clinics). Of these patients, 1,666 (70%) underwent urgent coronary angiography and primary PCI. Platelet glycoprotein llb/llla inhibitors were used in 40% and stent placement, in 78%. Postprocedural Thrombolysis In Myocardial Infarction (TIMI) 3 flow was documented in 86%. Intra-aortic balloon counterpulsation was used in 6%; mechanical ventilation, in 8.6%; and inotropic drugs/vasopressors, in 15.8%. Mortality rates in patients with Killip's class I or II ranged from 1% to 4.9% without negative influence of ischemic time. In patients with Killip's class III or IV, mortality rates increased from 18% to 54% with increasing ischemic delay up to 6 hours (p = 0.06) and remained at around 40% afterward. Independent predictors of mortality were age (odds ratio [OR] 1.29, 95% confidence interval [CI] 1.01 to 1.64, p = 0.04), resuscitated cardiac arrest (OR 2.44, 95% CI 1.18 to 5.05, p = 0.02), and postprocedural TIMI flow (OR 0.31, 95% CI 0.16 to 0.59). Overall mortality rates of patients who underwent a primary PCI strategy from 2000 to 2004 were significantly lower than in the control group of 152 consecutive patients who underwent thrombolysis from 1995 to 1996 (6.2% vs 16.4%; p <0.001). In conclusion, introduction of a primary PCI strategy significantly decreased hospital mortality in our unselected group of patients with STEMI compared with the thrombolytic era. Our study further emphasized the importance of shortening myocardial ischemic time, particularly in the presence of severe heart failure on admission.     

Usefulness of the TIMI Risk Index in predicting short- and long-term mortality in patients with acute coronary syndromes

In a cohort of 710 patients with acute coronary syndromes (ACSs), we demonstrated that the Thrombolysis In Myocardial Infarction Risk Index--a predictor of 30-day mortality in clinical trial patients with ST-elevation myocardial infarction (STEMI)--is a strong predictor of short- and long-term mortality with good discrimination ability (c statistics 0.77 to 0.79) among all subtypes of ACSs (STEMI, non-STEMI, and unstable angina pectoris). These results verify the utility of the Risk Index in unselected patients with STEMI, broaden its application to other types of ACSs, and extend its utility to stratification of long-term mortality risk.     

Risk stratification in pre-hospital management of myocardial infarction with ST elevation: value of a risk score profile

The aims of this study were to evaluate new tools of risk stratification in an unselected population of myocardial infarction (MI), usable in a pre-hospital situation, and to compare the risk profile of these patients with those of other clinical trials or myocardial infarction registries. The risk scores of death at 30 days (TIMI score and TIMI risk index) based on data available in the context of coronary emergencies, were applied to the population base of the MI observatory of myocardial infarction in the C?te d'Or (RICO). The risk profile was expressed by the smoothed graph of frequency distribution of each score. The TIMI score applied to the RICO population had a high discriminating power (c = 0.80) for mortality whereas TIMI risk index was less powerful (c = 0.57). The risk profile of the RICO population was comparable to that of InTIME II, ASSENT 2 and the NRMI with reperfusion registry. The NRMI without reperfusion and the MAGIC studies had different profiles characterised by a shift in the graph towards high risk patients. The authors conclude that risk stratification scores, like the TIMI score, are valuable tools for early triage in the management of MI patients. The risk profiles allow comparative analysis of risk levels of populations notably with respect to other registries and also with respect to randomised clinical trials.     

Clinical practice of primary angioplasty for the treatment of acute myocardial infarction in Germany: results from the MITRA and MIR registries

The pooled data of two German AMI registries: the Maximal Individual Therapy in Acute Myocardial Infarction (MITRA) study and the Myocardial Infarction Registry (MIR) were analysed in order to 1) describe current clinical practice of primary angioplasty in Germany, 2) compare the results of primary angioplasty with those of thrombolysis in the "real world" and 3) define subgroups of patients profiting probably most from primary angioplasty. Between 1994 and 1998, 20,306 AMI patients were included in the registries. At the 271 participating hospitals angioplasty facilities were available at 18.5%. Thrombolysis was still the most frequently used reperfusion therapy at hospitals without (96%) as well as hospitals with such facilities (55%). Transfer of AMI patients for angiography was performed in 3.6% of AMI patients admitted to hospitals without angioplasty facilities. A total of 9906 lytic eligible AMI patients with a pre-hospital delay of no more than 12 hours were treated with either primary angioplasty (n = 1327) or thrombolysis (n = 8579). Univariate analysis of hospital mortality showed a more favourable course for patients treated with primary angioplasty: 6.4% versus 11.3%, OR = 0.54, 95% CI: 0.43-0.67, p < 0.0001. This was confirmed by logistic regression analysis: multivariate OR = 0.58, 95% CI: 0.44-0.77, p < 0.0001. Primary angioplasty was associated with a lower mortality in all subgroups analysed. There was a significant correlation between mortality and the absolute risk reduction (r = 0.82, p < 0.0001) in the different subgroups, which showed an increasing absolute benefit of primary angioplasty compared to thrombolysis with increasing mortality risk.     

Prognostic impact of acute beta-blocker therapy on top of aspirin and angiotensin-converting enzyme inhibitor therapy in consecutive patients with ST-elevation acute myocardial infarction

The prognostic effect of beta-blocker treatment on ST-elevation acute myocardial infarction (STEMI) is controversially discussed in the era of reperfusion therapy. From the German multicenter registry Maximal Individual Therapy of Acute Myocardial Infarction PLUS (MITRA PLUS), 17,809 consecutive patients with STEMI treated with a guideline-recommended therapy with aspirin and an angiotensin-converting enzyme inhibitor were investigated; the prognostic effect of additional acute beta-blocker treatment was analyzed. Patients with cardiogenic shock were excluded. Of included patients, 77.6% received additional acute beta-blocker treatment and 22.4% did not. Patients with beta-blocker treatment were younger and more often received reperfusion therapy. Acute beta-blocker treatment was associated with a lower hospital mortality (univariate analysis 4.9% vs 10.8%, p <0.001; multivariate analysis odds ratio [OR] 0.70, 95% confidence interval [CI] 0.61 to 0.81). Acute beta blockade was significantly associated with a lower hospital mortality in patients without (OR 0.66, 95% CI 0.56 to 0.79) and with (OR 0.76, 95% CI 0.60 to 0.98) reperfusion therapy. The greatest benefit of acute beta-blocker treatment, measured by the number needed to treat to save 1 life, was found in patients with anterior MI, a heart rate > or =80 beats/min, no reperfusion therapy, female gender, and age > or =65 years. In conclusion, acute beta-blocker therapy in the clinical practice of treating patients with STEMI, in addition to aspirin and angiotensin-converting enzyme inhibitor therapy, was independently associated with a significant decrease in hospital mortality in patients with and without reperfusion therapy. High-risk patients with STEMI, such as elderly patients and patients without reperfusion therapy, showed a greater benefit of acute beta-blocker therapy than low-risk patients with STEMI.     

Endothelial dysfunction in young patients with acute ST-elevation myocardial infarction

Endothelial dysfunction may be particularly important in the pathogenesis of young patients with acute myocardial infarction (AMI), because they have different clinical characteristics compared with older patients. We investigated endothelial function in relation to AMI in this young age group. From January 2005 to March 2008, 29 of 31 consecutive patients with acute ST-elevation myocardial infarction (STEMI) who were <40 years old and received direct percutaneous coronary intervention (PCI) were enrolled in the study. We compared the coronary risk factors and flow-mediated vasodilation (FMD) in the brachial artery between the acute STEMI patients and 29 age- and gender-matched controls that did not have AMI. Baseline brachial artery diameter and responses to glyceryl trinitrate were similar between the two groups. In contrast, FMD was significantly lower in the young acute STEMI group than in the control (3.47 ± 4.08 vs. 7.45 ± 4.67%, p = 0.001) and correlated with the Thrombolysis in Myocardial Infarction (TIMI) risk score. The impaired FMD in the acute STEMI group was independent of smoking, hyperlipidemia, hypertension, nitrate use, or body mass index. In multiple logistic regression analysis, only FMD and age, not traditional cardiovascular risk factors, were found to be significantly associated with acute STEMI (odds ratio = 0.75, 95% CI 0.63-0.90, p < 0.01). In conclusion, independent of conventional risk factors, severe endothelial dysfunction occurs in young acute STEMI patients and correlates with TIMI score. In addition to age, impaired FMD is the only significant factor associated with acute STEMI in this young population.