The role of cardiac testing with the 0/1-hour high-sensitivity cardiac troponin algorithm evaluating for acute myocardial infarction.

BACKGROUND: The role of cardiac testing in the 3 zones (rule-out, observation, and rule-in) of the 0/1-hour algorithm to evaluate for acute myocardial infarction (AMI) has not been well studied. This study evaluated the 0/1-hour algorithm with a high-sensitivity cardiac troponin (hs-cTnI) assay and investigated cardiac testing in the 3 zones. METHODS: Patients (n = 552) at a single urban center were enrolled if they were evaluated for AMI. Blood samples were obtained at presentation, 1 hour, and 3 hours for hs-cTnI. Follow-up at 30 to 45 days for death/AMI was done. The results of echocardiograms, stress testing, and coronary angiography were recorded. RESULTS: In total, 45 (8.2%) had AMI (27 Type 1 and 18 Type 2) during the index hospitalization while at follow-up death/AMI occurred in 11 (2.0%) of patients. The rule-out algorithm had a negative predictive value for AMI of 99.6% while the rule-in zone had a positive predictive value of 56.6%. The MACE rate at follow-up was 0.4% for those in the rule-out group. There were 6/95 (6.3%) abnormal stress tests in the rule-out zone and 4 of these were false positives. CONCLUSIONS: The 0/1-hour algorithm had high diagnostic sensitivity and negative predictive value for AMI, and adverse events were very low in patients in the rule-out zone. Noninvasive testing in rule-out zone patients had low diagnostic yield.

Thrombin-receptor antagonist vorapaxar in acute coronary syndromes.

BACKGROUND: Vorapaxar is a new oral protease-activated-receptor 1 (PAR-1) antagonist that inhibits thrombin-induced platelet activation. METHODS: In this multinational, double-blind, randomized trial, we compared vorapaxar with placebo in 12,944 patients who had acute coronary syndromes without ST-segment elevation. The primary end point was a composite of death from cardiovascular causes, myocardial infarction, stroke, recurrent ischemia with rehospitalization, or urgent coronary revascularization. RESULTS: Follow-up in the trial was terminated early after a safety review. After a median follow-up of 502 days (interquartile range, 349 to 667), the primary end point occurred in 1031 of 6473 patients receiving vorapaxar versus 1102 of 6471 patients receiving placebo (Kaplan-Meier 2-year rate, 18.5% vs. 19.9%; hazard ratio, 0.92; 95% confidence interval [CI], 0.85 to 1.01; P=0.07). A composite of death from cardiovascular causes, myocardial infarction, or stroke occurred in 822 patients in the vorapaxar group versus 910 in the placebo group (14.7% and 16.4%, respectively; hazard ratio, 0.89; 95% CI, 0.81 to 0.98; P=0.02). Rates of moderate and severe bleeding were 7.2% in the vorapaxar group and 5.2% in the placebo group (hazard ratio, 1.35; 95% CI, 1.16 to 1.58; P<0.001). Intracranial hemorrhage rates were 1.1% and 0.2%, respectively (hazard ratio, 3.39; 95% CI, 1.78 to 6.45; P<0.001). Rates of nonhemorrhagic adverse events were similar in the two groups. CONCLUSIONS: In patients with acute coronary syndromes, the addition of vorapaxar to standard therapy did not significantly reduce the primary composite end point but significantly increased the risk of major bleeding, including intracranial hemorrhage. (Funded by Merck; TRACER ClinicalTrials.gov number, NCT00527943.).

Pheochromocytoma-Induced Takotsubo Cardiomyopathy.

Pheochromocytoma, a rare catecholamine-secreting tumor, typically manifests itself with paroxysmal hypertension, tachycardia, headache, and diaphoresis. Less often, symptoms related to substantial hemodynamic compromise and cardiogenic shock occur. We report the case of a 66-year-old woman who presented with abdominal pain. Examination revealed a large right adrenal mass, cardiogenic shock, and severe heart failure in the presence of normal coronary arteries. Within days, the patient's hemodynamic status and left ventricular ejection fraction improved markedly. Results of imaging and biochemical tests confirmed the diagnosis of pheochromocytoma-induced takotsubo cardiomyopathy. Medical therapy and right adrenalectomy resolved the patient's heart failure, and she was asymptomatic postoperatively. We recommend awareness of the link between pheochromocytoma and takotsubo cardiomyopathy, and we discuss relevant diagnostic and management principles.

Bundle branch block patterns, age, renal dysfunction, and heart failure mortality.

BACKGROUND: The determinants of bundle block patterns and their relationship to mortality in heart failure patients is not completely understood. METHODS: We evaluated 2907 consecutive patients admitted to an intensive care unit with decompensated heart failure over 8 years. Clinical and echocardiographic factors were analyzed using multivariate techniques. All-cause mortality was available on greater than 99.0% of patients at a median of 23 months after discharge. RESULTS: Right and left bundle branch blocks occurred in 211 (7.3%) and 386 (13.2%), p<0.0001. Older age, decreased left ventricular ejection fraction, and renal dysfunction were all found to be independently associated with bundle branch block patterns. Mortality rates for the subgroups of QRS<120 ms, right bundle branch block and left bundle branch block, over a mean follow-up of 23.4+/-2.6 months were 46.1%, 56.8% and 57.7%, p<0.0001 for comparison of QRS<120 ms versus either bundle pattern. Cox proportional hazards model adjusting for age, sex, ejection fraction, and renal function demonstrated graded decrements in survival in those with QRS<120 ms, right bundle branch block and left bundle branch block, p=0.03. CONCLUSIONS: In patients hospitalized with severe heart failure, age, left ventricular dysfunction, and renal dysfunction are associated with bundle branch block patterns. When controlling for these factors, bundle branch block patterns are independently associated with slightly higher all cause mortality after discharge.

Relationship between obesity and B-type natriuretic peptide levels.

BACKGROUND: The relationships among B-type natriuretic peptide (BNP) levels, body mass index (BMI), and congestive heart failure (CHF) as an emergency diagnosis are unknown. METHODS: Of 1586 participants in the Breathing Not Properly Multinational Study who had acute dyspnea, 1369 (86.3%) had BNP values and self-reported height and weight. Two independent cardiologists masked to the BNP results adjudicated the final diagnosis. RESULTS: Congestive heart failure was found in 46% of participants. Individuals with higher BMIs were younger and had more frequent edema on examination but were equally as likely to have CHF vs noncardiac sources of dyspnea. A nearly 3-fold difference was seen in mean +/- SD BNP values at the low and high extremes of the BMI groupings (516.7 +/- 505.9 vs 176.3 +/- 270.5 pg/mL, respectively; P< .001). The correlations between BMI and log BNP among those with and without CHF were r = -0.34 and r = -0.21, respectively (P< .001 for both). Multivariate analysis for the outcome of log BNP among a small subset with CHF (n = 62) found that Framingham score (P = .002), estimated glomerular filtration rate (P = .007), female sex (P = .03), New York Heart Association functional class (P = .09), and third heart sound (P = .08) were independent predictors. However, BMI was not found to be independently related to log BNP (P = .59). CONCLUSIONS: In patients with and without CHF, BNP levels are inversely related to BMI. When considering demographics, severity of disease, and renal function, BMI is not independently related to BNP levels in a small subgroup when detailed information about CHF severity is known.

Benefits of aspirin and beta-blockade after myocardial infarction in patients with chronic kidney disease.

BACKGROUND: There have been no randomized trials of cardioprotective therapy after acute myocardial infarction in patients with chronic kidney disease who should be largely eligible for aspirin (acetylsalicylic acid; ASA) and beta-blockers (BB) as a base of therapy. METHODS: We analyzed a prospective coronary care unit registry of 1724 patients with ST-segment elevation myocardial infarction. RESULTS: Usage rates were 52.3%, 19.0%, 15.2%, and 13.5% for ASA and BB (ASA+BB), BB alone, ASA alone, and no ASA or BB therapy. Patients who received ASA+BB were more likely to be male, free of earlier cardiac disease, and recipients of thrombolysis. Conversely, the absence of ASA+BB was observed in patients with heart failure on admission, left bundle branch block, atrial and ventricular arrhythmias, and shock. The combination of ASA+BB was used in 63.9%, 55.8%, 48.2%, and 35.5% of patients with corrected creatinine clearance values of >81.5, 81.5 to 63.1, 63.1 to 46.2, and <46.2 mL/min/72 kg (P <.0001). ASA+BB was used in 40.4% of patients undergoing dialysis. The age-adjusted relative risk reduction for the inhospital mortality rate was similar among all renal groups and ranged from 64.3% to 80.0% (all P <.0001). CONCLUSION: ASA+BB is an underused therapy in patients with acute myocardial infarction who have underlying kidney disease.

Implications of elevated cardiac troponin T in ambulatory patients with heart failure: a prospective analysis.

BACKGROUND: Elevated concentrations of cardiac troponin T (TnT) have been reported in patients hospitalized for decompensated heart failure (HF). We assessed whether elevated TnT levels are associated with the severity, etiology, and prognosis of HF in stable, ambulatory patients. METHODS: From 1998-1999, we prospectively collected data from 136 ambulatory patients with HF, New York Heart Association functional class II to IV, ejection fraction < or =35%, and no recent unstable angina, myocardial infarction, surgery, or coronary revascularization. Blood was obtained and analyzed by immunoassay for TnT, and patients were followed for 14.0 +/- 4.3 months for death or HF hospitalization (primary end point) and other adverse cardiovascular outcomes. RESULTS: Thirty-three patients (24%) had an elevated TnT level (> or =0.02 ng/mL). Mean TnT concentration did not differ by etiology of HF (0.002 +/- 0.03 ng/mL vs 0.02 +/- 0.04 ng/mL for ischemic and nonischemic etiologies, P =.25). Compared with patients with normal (undetectable) levels of TnT, patients with elevated TnT were significantly older, had worse functional class, and had poorer renal function. Elevated TnT concentrations were associated with increased relative risks (RR) of death or HF hospitalization (RR 2.7, 95% CI 1.7-4.3, P =.001) and death alone (RR 4.2, 95% CI 1.8-9.5, P =.001) during follow-up. Elevated TnT and New York Heart Association class were significant, independent predictors of death or HF hospitalization. Increased age and serum creatinine concentrations were significant independent predictors of death alone. CONCLUSIONS: Nearly one fourth of ambulatory patients with chronic HF have ongoing myocardial necrosis as shown by abnormal TnT values, which are associated with increased mortality and morbidity.

A change in serum myoglobin to detect acute myocardial infarction in patients with normal troponin I levels.

We sought to determine the sensitivity of a change in myoglobin for acute myocardial infarction (AMI) in patients who had normal levels of troponin I at presentation. Myoglobin increases as soon as 1 to 2 hours after symptom onset in AMI. The change in myoglobin may help identify AMI in patients with normal cardiac levels of troponin I on admission. A total of 817 consecutive patients who were examined in the emergency department for possible AMI were studied. In patients whose electrocardiograms were nondiagnostic, we measured levels of myoglobin and cardiac troponin I at presentation, at 90 minutes, and at 3 and 9 hours. Patients whose initial levels of myoglobin (<200 ng/ml) and cardiac troponin I (<0.4 ng/ml) were normal underwent receiver-operating characteristic curve analysis to determine the best cutpoint for a myoglobin increase from 0 to 90 minutes. Overall, 75 patients (9%) were diagnosed with AMI, including 27 patients with normal cardiac levels of troponin I at presentation. An increase of 20 ng/ml of myoglobin from 0 to 90 minutes provided maximal diagnostic utility in patients who did not have increased levels of myoglobin or cardiac troponin I at presentation. In the absence of an increased level of cardiac troponin I or myoglobin at presentation in the emergency department, a change >or=20 ng/ml of myoglobin at 90 minutes produced 83.3% sensitivity, 88.6% specificity, and 99.5% negative predictive value for AMI. The combined sensitivity of levels of cardiac troponin I and myoglobin and a change >or=20 ng/ml of myoglobin over 90 minutes was 97.3%. In emergency department patients with normal cardiac levels of troponin I at presentation, a change in myoglobin provides a highly accurate diagnosis of AMI within 90 minutes.

Transcutaneous ultrasound-facilitated coronary thrombolysis during acute myocardial infarction.

In preclinical experiments, the combination of transcutaneous, low-frequency ultrasound and thrombolytic therapy has shown improved patency rates over thrombolytics alone. A total of 25 patients with myocardial infarction were treated with a thrombolytic agent and adjunctive transcutaneous ultrasound. No unanticipated major adverse events were observed.

The independent association of renal dysfunction and arrhythmias in critically ill patients.

STUDY OBJECTIVES: The purpose of this study was to quantify the impact of baseline renal dysfunction on incidence and occurrence of cardiac arrhythmias in the coronary ICU. BACKGROUND: Renal dysfunction is an established predictor of all-cause mortality in the ICU setting. We set out to evaluate the independent contributory effect of renal dysfunction to arrhythmias and mortality in this population. DESIGN AND SETTING: We analyzed a prospective coronary care unit registry of 12,648 admissions by 9,557 patients over 8 years at a single, tertiary center. An admission serum creatinine level was available for 9,544 patients. Those patients not receiving long-term dialysis were classified into quartiles of corrected creatinine clearance with cutpoints of 46.2 mL/min/72 kg (group 1), 63.1 mL/min/72 kg, and 81.5 mL/min/72 kg. Dialysis patients (n = 527) were considered as a fifth comparison group (group 5). MEASUREMENTS AND RESULTS: Baseline characteristics including older age, African-American race, diabetes, hypertension, history of previous coronary disease, and heart failure were incrementally more common with increasing renal dysfunction strata. There were graded, independent increased risks for accelerated idioventricular rhythm (relative risk [RR], 2.43; 95% confidence interval [CI], 1.40 to 4.20; p = 0.002), sustained ventricular tachycardia (RR, 2.07; 95% CI, 1.02 to 4.22; p = 0.04), ventricular fibrillation (RR, 2.42; 95% CI, 1.13 to 5.15; p = 0.02), and complete heart block (RR, 3.64; 95% CI, 1.77 to 7.48; p = 0.0004, group 5 vs group 1). CONCLUSIONS: We conclude that baseline renal function is a powerful, independent predictor of cardiac arrhythmias in the coronary ICU population.

Mortality benefit of angiotensin-converting enzyme inhibitors after cardiac events in patients with end-stage renal disease.

UNLABELLED: HYPOTHESIS/INTRODUCTION: The risks and benefits of angiotensin-converting enzyme (ACE) inhibitors in patients with end-stage renal disease (ESRD) after cardiac events are unknown. We sought to determine the independent effect of ACE inhibitors (ACE-I) on long-term mortality in ESRD patients after cardiac events. MATERIALS AND METHODS: We analysed a prospective coronary care unit registry and identified 527 ESRD patients, 368 with complete data on medications prescribed, over eight years at a single, tertiary centre. RESULTS: The overall mean age was 64.4+13.8 years with 54.9% men, and 59.2% African-American. A total of 143/386 (37.0%) were prescribed ACE-I during the hospital stay for cardiac reasons, including congestive heart failure (CHF) 52.8% and acute coronary syndromes (ACS) 47.2%. There were no significant differences in the rates of hypotension or arrhythmias in those who were treated with ACE-I versus those who were not. Survival analysis over three years, adjusted for known confounders, demonstrated a 37% reduction in all-cause mortality in those who received ACE-I, (p=0.0145). CONCLUSIONS: In the setting of coronary care unit admission for CHF and ACS, ESRD patients selected for ACE-I, did not have increased rates of adverse haemodynamic or arrhythmic complications. The use of ACE-I conferred an independent mortality reduction over long-term follow-up.

Dyslipidemia in patients with angiographically confirmed coronary artery disease--an opportunity for improvement.

BACKGROUND: There are few data about lipid profiles in unselected patients with angiographically confirmed coronary artery disease (CAD). HYPOTHESIS: The study was undertaken to investigate the demographics, clinical characteristics, angiographic findings, and baseline lipid status of 1,000 consecutive unselected patients with angiographically confirmed CAD. METHODS: Between April 2001 and July 2002, we obtained informed consent and prospectively collected clinical characteristics, fasting lipid profiles, and angiographic results from 1,000 sequential patients with CAD confirmed by angiography. RESULTS: In these patients with confirmed CAD, 78% had history of hyperlipidemia. Although 62% were receiving lipid-lowering therapy, only 46% had a low-density lipoprotein target of < 100 mg/dl, and only 20% had achieved all four National Cholesterol Education Program-recommended lipid targets. CONCLUSIONS: Better strategies to ensure optimal lipid levels are required. One such method using computerized workflow is being evaluated in this population.

Paraganglioma as a rare cause of left ventricular thrombus in the setting of preserved ejection fraction: discussing the literature.

Paragangliomas and pheochromocytomas are catecholamine-secreting tumours which if remain undiagnosed may cause severe morbidity and mortality. In rare circumstances these tumours can cause left ventricular (LV) thrombi to form by inducing cardiomyopathy and subsequent embolic complications. After a thorough literature review, six previous cases were found that presented the formation of an LV thrombus in the setting of a pheochromocytoma or paraganglioma. A majority of these cases were associated with significant wall motion abnormalities and their cardiac ejection fraction (EF) was compromised. This is a rare case of a patient developing LV thrombi in the setting of a paraganglioma with normal cardiac EF. We present this case to compare the similarities and differences of our case with previously reported cases and emphasise the importance of suspecting these LV thrombi in patients with these neuroendocrine tumours.

The relationship between chest pain duration and the incidence of acute myocardial infarction among patients with acute chest pain.

OBJECTIVE: Eight to ten million individuals are evaluated for chest pain (CP) in Emergency Departments (ED) in the United States each year. CP characteristics are an important factor used to help determine a diagnosis. We studied the relationship between the duration of CP and the diagnosis of acute myocardial infarction (AMI) in patients evaluated in the ED. METHODS: The study population consisted of a sub-group analysis of a previously published study. The survey population consisted of 1024 consecutive encounters of patients who were evaluated for possible ACS in the ED of Henry Ford Hospital between January and May of 1999, CP duration could be obtained in 426 who were included in this analysis. RESULTS: Of the 426 patients included in the study, 38 (8.9%) had a final diagnosis of AMI, with a median CP duration of 120 minutes (interquartile range, 30-240 minutes), compared with 40 minutes (interquartile range, 6-180 minutes) in patients without AMI (p =0.003). In patients with CP duration less than 5 minutes, there were no AMIs and no deaths at 30 days. There were 10 patients dead at 30 days, with a median CP duration of 180 minutes (interquartile range, 120-1440 minutes) compared to 40 minutes (interquartile range, 10-180 minutes) in patients alive at 30 days (p = 0.011). A longer CP duration and ST depression of 1 mm of less were independently associated with a final diagnosis of AMI. CONCLUSION: Patients with AMI have longer duration of CP than those without AMI; patients with CP of short duration, less than 5 minutes, are unlikely to have AMI and have a good prognosis at 30 days.

Mortality implications of primary percutaneous coronary intervention treatment delays: insights from the Assessment of Pexelizumab in Acute Myocardial Infarction trial.

BACKGROUND: Prior studies demonstrate a direct relationship between treatment delays to primary percutaneous intervention and mortality in patients with ST-segment elevation myocardial infarction (STEMI). This analysis compared the relationship of symptom onset-to-balloon time and door-to-balloon time on mortality in patients with STEMI. METHODS AND RESULTS: We analyzed different treatment delays (symptom onset-to-balloon time, door-to-balloon time) and mortality in 5745 STEMI patients. Baseline characteristics, flow grade, 90-day mortality, and clinical outcomes were compared in patients stratified by treatment delay. Multivariable logistic regression modeling was performed to assess the independent and relative effect of each treatment delay on 90-day mortality. Female sex, increased age, and worse thrombolysis in myocardial infarction flow grade were significantly associated with longer symptom onset-to-balloon times and door-to-balloon times. Longer symptom onset-to-balloon time was significantly associated with worse 90-day mortality (3.7%, 4.2%, and 6.5% for time delays <3 hours, 3 to 5 hours, and >5 hours, respectively, P<0.0001). Similarly, longer door-to-balloon times were significantly associated with worse 90-day mortality (3.2%, 4.0%, 4.6%, and 5.3% for delays <60 minutes, 60 to 90 minutes, 90 to 120 minutes, and ≥120 minutes respectively, P<0.0001). In a multivariate model of 90-day mortality, door-to-balloon time (χ(2) 6.0, P<0.014), and symptom onset-to-hospital arrival (χ(2) 9.8, P<0.007) remained independent determinants. CONCLUSIONS: Both symptom onset-to-balloon time and hospital door-to-balloon time are strongly associated with 90-day mortality following STEMI. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00091637.

The recognition of acute coronary ischemia in the outpatient setting.

BACKGROUND: The missed diagnosis of acute myocardial infarction has been studied in the Emergency Department, but few studies have investigated how often coronary ischemia is correctly identified in the outpatient setting. METHODS: This was a single center retrospective observational study of patients with Health Alliance Plan medical insurance hospitalized at a US tertiary center with acute myocardial infarction in 2004. Outpatient encounters in the 30 days preceding acute myocardial infarction were reviewed by two independent cardiologists for presenting symptoms and diagnostic decision-making in order to classify patient presentations as acute coronary ischemia, stable angina or neither. RESULTS: There were 331 patients with acute myocardial infarction, including 190 (57%) with a primary diagnosis of AMI and evaluated by a physician in the preceding 30 days. This group included 68 patients with 95 documented outpatient encounters by a primary care physician, cardiologist, or other internal medicine specialist which formed the final study population. Mean interval between these encounters and AMI was 17 +/- 11 days. Of these patients, 7 (10%) had symptoms of acute coronary ischemia, 5 (7%) had stable angina symptoms, and 56 (83%) had no symptoms of coronary ischemia at their outpatient encounters. Of the 7 patients with acute coronary ischemic symptoms, 5 were correctly identified and 2 were misidentified. CONCLUSION: A majority of patients with subsequent AMI visit an outpatient provider in the month preceding AMI. However, few present with symptoms of coronary ischemia in the outpatient setting (10%) and these symptoms are not always identified as such.

Baseline Q-wave surpasses time from symptom onset as a prognostic marker in ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention.

OBJECTIVES: We assessed the incremental value of baseline Q waves over time from symptom onset as a marker of clinical outcome in ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Time from symptom onset is a central focus in STEMI patients. The presence of Q waves on the baseline electrocardiogram (ECG) has been suggested to be of incremental value to time from symptom onset in evaluating clinical outcomes. METHODS: We evaluated baseline Q waves and ST-segment resolution 30 min after primary percutaneous intervention (PCI) ECGs in 4,530 STEMI patients without prior infarction. Additionally, peak biomarkers; 90-day mortality; and the composite of death, congestive heart failure (CHF), or cardiogenic shock were assessed. RESULTS: Fifty-six percent of patients had baseline Q waves: they were older, more frequently male and diabetic, and had a more advanced Killip class. Patients with baseline Q waves had greater mortality and a higher composite rate of death, CHF, and shock versus patients without baseline Q waves at 90 days (5.3% vs. 2.1% and 12.1% vs. 4.8%, respectively, both p < 0.001). Complete ST-segment resolution was highest, whereas 90-day mortality and the composite outcome were lowest among those randomized < or =3 h without baseline Q waves. After multivariable adjustment, baseline Q-wave but not time from symptom onset was significantly associated with a 78% relative increase in the hazard of 90-day mortality and a 90% relative increase in the hazard of death, shock, and CHF. CONCLUSIONS: Baseline Q waves in STEMI patients treated with primary PCI provide an independent prognostic marker of clinical outcome. These data might be useful in designing future clinical trials as well as in evaluating patients for triage and potential transfer for planned primary PCI. (Pexelizumab in Conjunction With Angioplasty in Acute Myocardial Infarction [APEX-AMI]; NCT00091637).

Modified thrombolysis in myocardial infarction (TIMI) risk score to risk stratify patients in the emergency department with possible acute coronary syndrome.

OBJECTIVE: To assess the prognostic utility of the Thrombolysis in Myocardial Infarction (TIMI) risk score in patients in the emergency department (ED) evaluated for possible acute coronary syndrome (ACS). BACKGROUND: The ability of the TIMI risk score to risk stratify patients at initial presentation in the ED with chest pain of unclear etiology is uncertain. METHODS: We investigated the prognostic utility of the TIMI risk score in 947 consecutive patients evaluated in the ED for possible ACS. A multivariate analysis was done to evaluate the independent predictive power of the individual components of the TIMI risk score to predict an adverse event at 30 days (all-cause death, myocardial infarction, and coronary revascularization). RESULTS: There were 151 (16%) patients diagnosed with ACS. At 30 days there were 48 (5%) deaths, 84 (9%) myocardial infarctions, and 49 (5%) coronary revascularization procedures. The mean TIMI risk score was significantly higher in patients with an adverse event compared with those without (2.6 +/- 1.3 vs. 1.7 +/- 1.2, P < 0.0001). Four of the 7 TIMI risk factors (age > or = 65 years, ST segment deviation > or = 0.5 mm elevated troponin I, and coronary stenosis > or = 50%) were independently associated with adverse events. A simplified TIMI risk score was computed and was found to have similar prognostic ability as the 7 variable TIMI risk score. CONCLUSION: A modified TIMI risk score may simplify risk stratification of ED patients with undifferentiated chest pain.