Predicting outcome after thrombolysis in acute myocardial infarction according to ST-segment resolution at 90 minutes: a substudy of the GUSTO-III trial. Global Use of Strategies To Open occluded coronary arteries

Background Resolution of ST-segment elevation after thrombolysis for acute myocardial infarction has been shown to have prognostic significance 3 hours (180 minutes) after the initiation of therapy. Whether prognostically useful information can be achieved as early as 90 minutes after thrombolysis is unknown. Methods An electrocardiographic substudy of 2352 patients from the Global Use of Strategies To Open occluded coronary arteries (GUSTO-III) trial was undertaken to compare outcomes according to ST-segment resolution at 90 minutes versus 180 minutes after administration of thrombolytic therapy. Results Of 2352 patients in the substudy, 2241 had a baseline and 90-minute electrocardiogram, and 2218 had a baseline and 180-minute ECG. Complete ST-segment resolution occurred in 44.2% of patients at 90 minutes and 56.5% of patients at 180 minutes. ST-segment resolution at both 90 and 180 minutes was associated with lower 30-day and 1-year mortality. Multivariate analysis revealed ST-segment resolution at 90 minutes to be an equally strong predictor of 30-day mortality as resolution at 180 minutes. Patients who were at particularly high risk for mortality were those aged >70 years, those who presented with Killip class >1, and those with anterior infarctions. Conclusions The presence of ST-segment resolution on standard 12-lead electrocardiographic monitoring 90 minutes after thrombolysis is a useful independent predictor of mortality at 30 days and 1 year. The potential for obtaining prognostic results as early as 90 minutes after thrombolysis sets a new precedent for optimum electrocardiographic monitoring times in these patients. (Am Heart J 2002;144:81-8.)     

Pharmacodynamic profile of the direct thrombin antagonist bivalirudin given in combination with the glycoprotein IIb/IIIa antagonist eptifibatide

Background Because of the adverse characteristics associated with heparin, direct antagonists of thrombin have been investigated as anticoagulants during percutaneous coronary interventions. However, the hematologic and clinical interactions between direct thrombin antagonists and inhibitors of platelet glycoprotein IIb-IIIa are incompletely explored. Methods Forty-two patients who underwent elective percutaneous coronary intervention were randomized to receive a bivalirudin 1.0 mg/kg bolus followed by a 4-hour infusion at 2.5 mg/kg/h; a bivalirudin 0.75 mg/kg bolus followed by a 4-hour infusion at 1.75 mg/kg; or a heparin 60 U/kg bolus. All the patients also received eptifibatide, given as 2 sequential boluses of 180 μg/kg followed by a 2 μg/kg/min infusion for 18 to 24 hours, and aspirin. Results After the bolus dose of the study drug, turbidimetric platelet aggregation in response to 5 μmol/L adenosine diphosphate increased in patients assigned to heparin but not those assigned to bivalirudin. After eptifibatide, platelet aggregation was eliminated in all 3 treatment groups. The effect of heparin and the effects of both bivalirudin regimens on the formation of thrombin antithrombin complexes and prothrombin fragment 1.2 were comparable. Neither agent affected the formation of platelet-monocyte complexes or expression of CD 63 lysosomal antigen. There were no major bleeding events, and a single non-Q-wave myocardial infarction (MI) occurred in a patient treated with bivalirudin. Conclusion These findings show the feasibility of combining the direct thrombin antagonist bivalirudin with a potent antagonist of platelet glycoprotein IIb-IIIa. Clinical trials are needed to assess the safety and efficacy of this combination. (Am Heart J 2002;143:585-93.)     

Primary coronary angioplasty compared with intravenous thrombolytic therapy for acute myocardial infarction: six-month follow up and analysis of individual patient data from randomized trials

Background Overviews of trials suggest that percutaneous transluminal coronary angioplasty (PTCA) may be more effective than thrombolysis. However, whether these effects are sustained beyond hospital discharge, and the extent to which the results are applicable to a broad cross section of patients and the wider community are unknown. We compared the effectiveness of primary PTCA and thrombolysis in acute myocardial infarction during a 6-month follow-up period.Methods Detailed individual patient data were collected from randomized trials commenced from 1989 to 1996 that compared primary PTCA with thrombolysis. Data were combined to produce estimates of relative reduction in events at 30 days and 6 months for the group and for predefined clinical subgroups. Treatment effects were also assessed in relation to several study-related factors.Results Eleven trials were identified. The mortality rate at 30 days was 4.3% for 1348 patients randomized to undergo PTCA, and 6.9% for 1377 patients assigned to thrombolytic therapy (relative risk [RR] 0.62, 95% CI 0.44-0.86, P = .004). At 6 months, the mortality rate was 6.2% for PTCA and 8.2% for thrombolysis (RR 0.73, 95% CI 0.55-0.98, P = .04). Combined death and reinfarction rates at 30 days were 7.0% for PTCA and 12.9% for thrombolysis, with a sustained effect at 6 months (RR 0.60, 95% CI 0.48-0.75, P < .0001). The risk of hemorrhagic stroke at 30 days was lower in the PTCA group (RR 0.06, 95% CI 0.0-0.50, P = .009). The relative treatment effect did not vary across clinically important subgroups, but the absolute benefit varied according to baseline risk. The relative treatment effect varied across the trials and according to the thrombolytic comparator used, the delay in performing PTCA, and the recruitment rate.Conclusion In the context of these trials, primary PTCA was more effective than thrombolytic therapy in reducing death, reinfarction, and stroke, with the greatest absolute benefit in patients who were at the highest risk. These benefits appear to be sustained for 6 months. The effect of treatment varied significantly across the trials, and this raises issues about how widely the results can be applied. (Am Heart J 2003;145:47-57.)     

Heart failure after myocardial infarction: prevalence of preserved left ventricular systolic function in the community

Background Studies have reported that a large proportion of the cases of congestive heart failure (CHF) with mixed etiologies have preserved left ventricular systolic function. Whether this is the case in subjects with CHF after myocardial infarction (MI) is not known. This study was undertaken to examine the prevalence and characteristics associated with CHF in patients who had preserved ejection fraction (LVEF) after MI. Methods Clinical characteristics and LVEF were ascertained in a population-based cohort of patients with CHF after incident MI in Olmsted County, Minn. All MIs were validated by use of standardized epidemiological criteria, and all episodes of CHF were validated by use of Framingham criteria. Results Between 1979 and 1994, 1658 patients had an MI, and 644 of these patients (38%) had CHF during 7.4 ± 5.4 years of follow-up. Of these patients, 395 (61%) underwent LVEF assessment. Preserved LVEF (ie, ≥50%) was present in 30% of cases, and this proportion did not change with time. The proportion of women with CHF and preserved LVEF (37%) was greater than the proportion of men (23%, P = .002). The positive association between female sex and preserved LVEF remained significant after adjustment (odds ratio 1.97, 95% CI 1.26-3.07, P = .003). The highest tertile of peak creatinine phosphokinase level was negatively associated with preserved LVEF (odds ratio 0.51, 95% CI 0.29-0.89). Conclusion A notable proportion of cases of CHF after MI have preserved LVEF. This underscores the burden of CHF with preserved LVEF in a well-defined group of patients with documented coronary disease. CHF with preserved LVEF after MI is associated with female sex and smaller MI size. (Am Heart J 2003;145:742-8.)     

Randomized comparison of enoxaparin with unfractionated heparin for the prevention of venous thromboembolism in medical patients with heart failure or severe respiratory disease

Background We compared the efficacy and safety of the low-molecular weight heparin enoxaparin with unfractionated heparin (UFH) for the prevention of venous thromboembolic disease in patients with heart failure or severe respiratory disease. Methods This was a multicenter, controlled, randomized, open study in which patients received either enoxaparin (40 mg once daily) or UFH (5000 IU 3 times daily) for 10 ± 2 days in 64 medical departments in Germany. Patients were stratified and enrolled according to their underlying disease: severe respiratory disease or heart failure. The primary efficacy parameter was a thromboembolic event up to 1 day after the treatment period. Results Of the 665 patients enrolled, 451 patients were able to be evaluated in the primary efficacy analysis. The incidence of thromboembolic events was 8.4% with enoxaparin and 10.4% with UFH. Enoxaparin was at least as effective as UFH, with a 1-sided equivalence region of −4% (90% CI −2.5-6.5, P = .015). Enoxaparin was associated with fewer deaths, less bleeding, and significantly fewer adverse events (45.8% vs 53.8%, P = .044). Conclusions Enoxaparin is at least as effective as UFH in the prevention of thromboembolic events in patients with heart failure or severe respiratory disease. Its beneficial safety profile and once-daily administration is advantageous for inpatient and outpatient use. (Am Heart J 2003;145:614-21.)     

Assessment of the safety and efficacy of the DUETT vascular hemostasis device: final results of the safe and effective vascular hemostasis (SEAL) trial

Objective We sought to determine the safety and efficacy of the novel DUETT vascular hemostasis device in comparison with standard manual compression after diagnostic and interventional coronary procedures. Background Vascular hemostasis devices are increasingly used to improve patient comfort and speed mobilization after coronary and peripheral vascular procedures. Currently available devices have certain limitations, however. Methods At 16 clinical sites, 630 patients who underwent diagnostic or interventional coronary procedures were randomized 5:3 to the DUETT sealing device or standard manual compression. The primary study end points were time to hemostasis and ambulation and the incidence of major vascular complications at 30 days. Results Time to hemostasis from the completion of the procedure (catheter removal; median) was 14 minutes (interquartile range [IQR], 10, 17 minutes) in the DUETT group and 195 minutes (IQR, 46, 351 minutes) in the standard compression group (P <.001), and time from sheath removal (median) was 7 minutes (IQR, 6, 8 minutes) and 20 minutes (IQR, 15, 30 minutes) for the 2 groups, respectively (P <.001). Time to ambulation from catheter removal (median) was 338 minutes (IQR, 223, 526 minutes) in the DUETT group and 705 minutes (IQR, 400, 1120 minutes) in the standard compression group (P <.001). Major complications occurred in 3.6% of the DUETT group and 1.7% of the standard compression group (P = .22), with a diminishing risk of complications in the DUETT group as experience was accrued. Similar benefits from DUETT use were seen in patients who underwent both diagnostic and interventional procedures. Conclusion The DUETT sealing device allows immediate arterial sheath removal after both diagnostic and interventional procedures, dramatically reducing time to hemostasis and patient ambulation without compromising patient safety in comparison with standard compression techniques. (Am Heart J 2002;143:612-9.)     

Serum glucose and lipid levels in adult congenital heart disease patients

Atherosclerosis has been correlated with known cardiovascular risk factors such as serum glucose or lipid levels. Because congenital heart disease patients tend to survive until adulthood, atherosclerosis has also become a matter of concern in these patients. One hundred fifty-eight congenital heart disease patients and 152 patients selected at random from the population were studied and compared to determine serum glucose, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein cholesterol, and triglycerides levels. Both groups had similar socioeconomic status levels and the same environmental influences. Significant differences were seen between congenital heart disease patients and the control group, after sex, age, and body mass index adjustment, in fasting plasma glucose (97.7 [94.2-101.2] vs 86.9 [83.2-90.7], P < .001), total cholesterol (171.5 [165.7-177.3] vs 199.8 [90.7-206.0], P < .001), LDL cholesterol (103.9 [98.8-108.8] vs 123.8 [118.5-129.1], P < .001), and high-density lipoprotein cholesterol (48.1 [46.2-50.0] vs 54.2 [52.1-56.2], P < .001) levels. Nonsignificant differences were seen in triglycerides concentrations. Those patients with ventricular septal defect, coarctation of the aorta, and cyanosis had the lowest total cholesterol and LDL cholesterol concentrations. Congenital heart disease patients have lower plasma cholesterol concentrations and higher serum glucose levels than noncongenital ones.     

Perceptions of chest pain differ by race

Background African American patients are less likely to receive thrombolytic therapy and coronary revascularization than are white patients. Delay and clinical presentation may be keys to understanding differences in care. Objective To determine how symptom recognition and perception influence clinical presentation as a function of race, we characterized symptoms and care-seeking behavior in African American and white patients seen in the ED with chest pain. Methods The prospective study was conducted from April 1999 to September 1999 among patients who were seen in the ED and were admitted or observed in the ED Chest Pain Unit (n = 215). Interviews were conducted within 48 hours with a structured set of questions. Results Thirty-one percent of white patients and 8.9% of African American patients were admitted with a diagnosis of acute myocardial infarction (P = .001). African American patients were as likely as white patients to report “typical” objective symptoms but were more likely to attribute their symptoms to a gastrointestinal source rather than a cardiac source (P = .05). Of those patients with the final diagnosis of myocardial infarction (n = 45), 61% of African American patients attributed symptoms to a gastrointestinal source and 11% to a cardiac source, versus 26% and 33%, respectively, for white patients. The median prehospital delay for African American patients was 263 minutes (interquartile range, 120 to 756 minutes), similar to the 247 minutes for white patients (interquartile range, 101 to 825 minutes, P = .72), despite African American patients (80%) being more likely than white patients (66%) to perceive their symptoms as severe/life-threatening at onset (P = .05). Conclusion Racial differences in symptom perception exist. Although the proportion of objectively defined typical symptoms were similar, self-attribution was more often noncardiac in African American patients than in white patients. Self-attribution, in addition to objective clinical findings, is likely to influence caregiver diagnostic approaches and therefore therapeutic approaches, and merits further study. (Am Heart J 2002;144:51-9.)     

Long-term outcome of primary percutaneous transluminal coronary angioplasty for low-risk acute myocardial infarction in patients older than 80 years: a single-center, open, randomized trial

Background Although coronary reperfusion therapy with thrombolytic agents or percutaneous transluminal coronary angioplasty (PTCA) immediately after acute myocardial infarction (AMI) has survival benefits for younger patients, the effect of coronary reperfusion therapy for very elderly (aged 80 years and older) patients with AMI remains controversial. Methods and Results We studied 120 patients aged 80 years and older at relatively low risk with AMI. The patients were randomized into a primary PTCA group (n = 61) or a “conservative” no-PTCA group (n = 59). Long-term follow-up examination was conducted with regard to endpoints, which included all causes of death, cardiac death, nonfatal re-MI, the development of congestive heart failure, and cerebral vascular accident. End-diastolic volume index and end-systolic volume index were significantly increased in both groups at follow-up examination 6 months after AMI. However, left ventricular ejection fraction, end-diastolic volume index, and end-systolic volume index were similar between both groups. With endpoints of all causes of death, cardiac death, reinfarction, congestive heart failure, and cerebral vascular accident, a 3-year Kaplan-Meier event-free survival rate analysis revealed no significant benefits in the PTCA group. Anteroseptal MI, multivessel disease, and left ventricular ejection fraction were significantly associated with the combined events with multivariate Cox proportional hazards analysis results. Conclusion First, primary PTCA for very elderly patients with AMI appears to have few beneficial effects on combined events during a 3-year period. Second, early PTCA did not prevent left ventricle remodeling after AMI in patients with AMI at relatively low risk. (Am Heart J 2002;143:497-505.)     

Abciximab improves 6-month clinical outcome after rescue coronary angioplasty

Background Few data are available concerning the effects on clinical outcome and left ventricular function of abciximab administration in patients undergoing rescue percutaneous transluminal coronary angioplasty (PTCA) after failed thrombolysis for acute myocardial infarction. The aim of the study was to investigate such effects. Methods Eighty-nine consecutive patients referred to our laboratory from other hospitals for rescue PTCA within 24 hours from the onset of chest pain were prospectively randomized before the procedure to abciximab treatment (44 patients) or placebo (45 patients). No significant differences in baseline characteristics were observed between the 2 groups. Study end points were the occurrence of major adverse cardiac events (MACE) such as death, reinfarction, congestive heart failure, target lesion revascularization, or recurrent ischemia at 30-day and 6-month follow-up and the occurrence of periprocedural bleeding. Results Mean time from symptom onset to reperfusion was 8.5 ± 5.4 hours; rescue PTCA was successful in 96% of patients. The incidence of major, moderate, and minor bleeding was similar in the 2 groups. At 30-day follow-up, the echocardiographic left ventricular wall motion score index showed a significantly higher improvement in the abciximab group versus the placebo group (P < .001). At 6-month follow-up, the incidence of MACE was 11% in the abciximab group versus 38% in the placebo group (P = .004). Abciximab administration (P = .003) and cardiogenic shock (P = .005) were the only independent predictors of the occurrence of MACE at multivariable analysis. Conclusion Treatment with abciximab during rescue PTCA positively affects clinical outcome at 6-month follow-up without increasing periprocedural bleeding. (Am Heart J 2002;143:334-41.)     

Use patterns of low-molecular weight heparin and the impact on length of stay in patients hospitalized for atrial fibrillation

Background Low-molecular weight heparin, although unproven as a protective anticoagulant in atrial fibrillation, is not uncommonly used in this clinical setting. This investigation sought to assess the prevalence of its use for atrial fibrillation and its impact on length of hospital stay. Methods A retrospective analysis of patients admitted to the cardiology service at a university hospital with the primary diagnosis of atrial fibrillation was conducted for a 6-month interval in 3 consecutive years. Baseline demographic and clinical information, anticoagulation status, and length of hospital stay were compared. Results A total of 213 patients were identified and divided into 2 groups (before and after low-molecular weight heparin availability). Low-molecular weight heparin use increased with time (0% in 1997, 16.9% in 1998, 24.1% in 1999) and was associated with a significant reduction in length of hospital stay, from 3.3 ± 2.8 days to 2.4 ± 2.1 days (P = .03), and a trend toward a decreased international normalized ratio. Conclusions This investigation noted the increasing trend toward the use of low-molecular weight heparin as a protective anticoagulant for atrial fibrillation, despite the lack of controlled data about its efficacy. The observed reduction in length of hospital stay is implicated as a potential reason for the use of low-molecular weight heparin. (Am Heart J 2003;145:665-9.)     

Relationship between initial white blood cell counts,stage of acute myocardial infarction evolution at presentation,and incidence of Thrombolysis In Myocardial Infarction-3 flow after streptokinase

Background The initial white cell counts in patients with acute myocardial infarction (AMI) may reflect the stage of AMI evolution, and may also be related to the efficacy of thrombolytic agents in recanalizing occluded epicardial arteries.Methods In 312 patients with a first AMI, we divided the initial white cell counts into quartiles and investigated their relationship with the time to treatment and the incidence of Thrombolysis In Myocardial Infarction (TIMI)-3 flow at 90 minutes after commencement of streptokinase.Results A longer time from symptom onset to treatment was independently associated with a higher neutrophil count and a lower non-neutrophil count. These times were 2.6, 2.9, and 3.8 hours, respectively, in the lowest, combined second and third (ie, middle), and highest neutrophil quartiles (P = .003), and 4.3, 3, and 1.9 hours, respectively, in the lowest, combined middle, and highest non-neutrophil quartiles (P < .0001). TIMI-3 flow was achieved in 44% of the lowest total white cell quartile, 41% of the combined middle quartile, and 60% of the highest quartile (P = .05). The corresponding figures were 47%, 49%, and 46% (P = .657) for the neutrophil quartiles, and 32%, 46%, and 68% for the non-neutrophil quartiles (P = .001). On multivariable analysis, the incidence of TIMI-3 flow was independently and positively associated with the initial non-neutrophil count. Patients with non-neutrophil counts in the highest quartile had a higher incidence of TIMI-3 flow than those in the lowest quartile (odds ratio 2.86, 95% CI 1.32-6.23, P = .008).Conclusions A longer time from symptom onset to thrombolysis for AMI is associated with a higher neutrophil count and a lower non-neutrophil count at presentation. A higher neutrophil count is not associated with worse epicardial blood flow at 90 minutes after streptokinase, and a higher non-neutrophil count predicts a greater likelihood of achieving TIMI-3 flow. (Am Heart J 2003;145:95-102.)     

Cardiac troponin I: a potential marker of exercise intolerance in patients with moderate heart failure

Background In severe heart failure, increased values of cardiac troponins have been detected during decompensation. In this study, we investigated whether an increase of cardiac troponin I can be observed after symptom-limited exercise and after an exercise training session in patients with moderate heart failure. Methods Twenty-seven patients with moderate heart failure (New York Heart Association II-III, ejection fraction 31% ± 8%) were compared with 9 patients with mild heart failure and 10 subjects without heart failure. They underwent a symptom-limited exercise test and a bicycle exercise training session at >80% of maximal heart rate over 20 to 30 minutes. Plasma cTnI levels were measured at baseline, after symptom-limited exercise (hourly for 5 hours), and after training (4 and 10 hours). Results Patients with moderate heart failure showed an increase of cTnI from 37 ± 49 pg/mL to 73 ± 59 pg/mL (P < .001) after symptom-limited exercise. Four patients with moderate and 1 with mild heart failure and normal cTnI values at rest showed an increase of cTnI above 100 pg/mL after acute exercise but not after training. Subjects without heart failure had lower cTnI levels at rest and significantly lower values after symptom-limited exercise and training (P < .05 for each). Conclusion Patients with symptomatic heart failure reveal an increase of cTnI after symptom-limited exercise at levels that indicate minor myocardial damage. The prognostic impact of this finding should, therefore, be further investigated. (Am Heart J 2002;144:351-8)     

Comparative fibrinolytic activity of front-loaded alteplase and the single-bolus mutants tenecteplase and lanoteplase during treatment of acute myocardial infarction

Background Quantification of fibrinolytic activity (FAct) in clinical practice has been abandoned because of the complexity of existing assays. The relationship between thrombolytic drug concentration and FAct is complex. FAct profiles of currently used thrombolytic drugs were not characterized. Methods By use of a system that quantifies FAct by shortening of clot lysis onset time (LOT), we measured LOT in vitro with incremented concentrations of alteplase (t-PA) and tenecteplase (TNK-tPA) and ex vivo in patients with acute myocardial infarction who were receiving front-loaded t-PA (n = 31), 30 to 40 mg TNK-tPA (n = 19), and 120 kU/kg lanoteplase ([n-PA] n = 23). Results In vitro, FAct depended on drug concentration by means of a double exponential model revealing 2 distinct activity zones (weak/strong). Ex vivo, no FAct was detected before agent administration (LOT > 1200 seconds). Ten minutes after a bolus was given, FAct was sharply increased in all patients, but it increased more with TNK-tPA than with t-PA or n-PA (mean LOT of 109, 125, and 130 seconds, respectively, P < .05). At 90 minutes, accelerated infusion of t-PA resulted in FAct that remained stronger than that observed for TNK-tPA (P < .0001) or n-PA (P = .011). At 180-minutes, significant FAct (LOT <600 seconds) was only observed in patients who received n-PA. Conclusion This study provides the first direct comparison of FAct between t-PA, TNK-tPA, and n-PA by use of the LOT test, the results of which are reliably related to drug concentration. The ideal FAct profile would combine an immediate strong FAct of relatively short duration, as seen with TNK-tPA, that may contribute to its better efficacy/safety profile in the Assessment of Safety and Efficacy of a New Thrombolytic Agent-2 (ASSENT-2) trial. Prolonged FAct after n-PA may contribute to increased hemorrhagic complications, as seen in the Intravenous n-PA for Treatment of Infarcting Myocardium Early-2 (InTIME-2) trial. Thus, characterizing FAct profiles might provide insights in developing more efficient thrombolytic regimens. (Am Heart J 2003;145:217-25)     

Bivalirudin with planned or provisional abciximab versus low-dose heparin and abciximab during percutaneous coronary revascularization: results of the Comparison of Abciximab Complications with Hirulog for Ischemic Events Trial (CACHET)

Background The direct thrombin inhibitor bivalirudin has previously been associated with better efficacy and lower hemorrhage risk than heparin during balloon angioplasty. This agent has not yet been tested with stenting or in combination with platelet glycoprotein IIb/IIIa antagonists. Methods and Results In a pilot trial, 268 patients who underwent coronary intervention were randomized in 3 sequential phases to treatment with bivalirudin (with or without abciximab) or the control regimen of low-dose weight-adjusted heparin with abciximab. Patients in the bivalirudin arms received bivalirudin (1.0 mg/kg bolus, infusion of 2.5 mg/kg/h for 4 hours) plus abciximab in phase A, bivalirudin (0.5 mg/kg bolus, infusion of 1.75 mg/kg/h for the procedure duration) plus provisional (“rescue”) abciximab in phase B, or bivalirudin (0.75 mg/kg bolus, infusion of 1.75 mg/kg/h for the procedure duration) plus provisional abciximab in phase C. Abciximab was necessitated on a provisional basis in 24% of the patients in the bivalirudin arms of phases B and C. A composite clinical endpoint of death, myocardial infarction, repeat revascularization, or major bleeding by 7 days occurred in 3.3%, 5.9%, 0, and 10.6% of the patients in the bivalirudin phase A, bivalirudin phase B, bivalirudin phase C, and heparin plus planned abciximab arms, respectively (P = .018 for the pooled bivalirudin groups versus the heparin group). Conclusion Bivalirudin with planned or provisional abciximab may be at least as safe and effective as low-dose heparin plus abciximab during percutaneous coronary intervention. (Am Heart J 2002;143:847-53.)     

A score predicts failure of reperfusion after fibrinolytic therapy for acute myocardial infarction

Background A rapid, accurate, noninvasive means of predicting the likelihood of failure to achieve Thrombolysis In Myocardial Infarction (TIMI) grade 3 flow within 90 minutes after the start of fibrinolysis with streptokinase could help to identify patients who might benefit from additional therapies that aim to preserve myocytes. Methods We measured ST recovery, which was assessed as the sum of ST deviation on a 12-lead electrocardiogram, and blood levels of the myocardial proteins, troponin T, creatine kinase myocardial band (CK-MB), and myoglobin before and 60 minutes after commencing streptokinase infused for 30 to 60 minutes in 107 patients, who presented within 12 hours of symptom onset and underwent angiography at 90 minutes. Results At 90 minutes, 56% of patients (95% CI 46-66) had TIMI-3 flow. The baseline levels of troponin T, CK-MB, and myoglobin were more commonly below the discrimination values in patients with TIMI-3 flow than in patients without TIMI-3 flow (all P < .005). On multivariate analysis, the factors associated with failure to achieve TIMI-3 flow were ST recovery of <70% (P = .009), a 60-minute/baseline troponin T ratio of ≤5 (P = .0004), a baseline CK-MB level of >4 μg/L (P = .039), or a baseline myoglobin level of >85 μg/L (P = .048). Age and a history of myocardial infarction were added into the multivariate model, and a risk score was developed to predict the likelihood of failure to achieve TIMI-3 flow. A score of ≤2 excluded failure to achieve TIMI-3 flow with 96% accuracy, and a score of ≥7 predicted failure to achieve TIMI-3 flow with 90% accuracy. Conclusion Failure to achieve TIMI-3 flow in the infarct-related artery within 90 minutes after the start of fibrinolysis can be accurately predicted at approximately 60 minutes by a score incorporating clinical variables, ST recovery, and the 60-minute/baseline ratios of troponin T, CK-MB, and/or myoglobin levels. This score may facilitate triage of patients at 60 minutes after fibrinolysis to additional reperfusion therapies. (Am Heart J 2003;145:508-14.)     

Comparison of 2-dimensional echocardiography and myocardial perfusion imaging for diagnosing myocardial infarction in emergency department patients

Background Both 2-dimensional echocardiography and myocardial perfusion imaging (MPI) with technetium-99m based agents have been used to identify patients in the emergency department with myocardial infarction (MI). However, the inclusion of small numbers of patients in prior studies limits the accurate assessment of sensitivity of the 2 techniques. Methods Gated MPI was used as part of the initial triage process in patients initially considered at low to moderate risk for acute coronary syndromes (no ST elevation or depression). Patients diagnosed with MI also underwent echocardiography. MPI results were considered positive if there was a perfusion defect associated with abnormal wall motion or thickening, and echocardiographic results were considered positive if there were segmental wall motion abnormalities or ejection fraction of less than 40%. Results Both tests were performed on 141 patients. The sensitivities for MI for echocardiography (91%; 95% CI, 86%-95%) and MPI (89%; 95% CI, 83%-94%) were similar. Patients who had either negative echocardiographic results (peak creatine kinase level [CK], 325 ± 206 vs 582 ± 614 U/L; P = .003) or negative MPI results (peak CK, 313 ± 227 vs 590 ± 620 U/L; P = .001) had smaller MIs as estimated with peak CK values. Ejection fraction was highly correlated between the 2 techniques (r = 0.82; P <.001). Conclusion Both echocardiography and MPI have a high sensitivity for identifying patients in the emergency department who have MI. False negative studies with either technique were associated with small MIs. (Am Heart J 2002;143:659-67.)     

CD14 gene -159C/T polymorphism is not associated with coronary artery disease and myocardial infarction

Background Monocyte differentiation antigen CD14 is considered an important cell-activating mediator of inflammatory responses that may result in atherosclerosis, coronary artery disease (CAD), thrombus formation, and myocardial infarction (MI). We assessed the possibility that a C → T nucleotide substitution polymorphism in the promoter (position −159) of the gene encoding CD14 constitutes a risk factor for CAD and MI. Methods Consecutive patients with significant, angiographically documented coronary stenoses but without symptoms or signs of old or acute MI constituted the group with CAD (n = 998). Consecutive patients with angiographic examination with old or acute MI constituted the group with MI (n = 793). Subjects matched with patients for age and gender but without angiographic evidence of CAD and without symptoms or signs of MI (n = 340) and a group of healthy blood donors (n = 104) served as controls. Results Genotype distributions of the −159C/T polymorphism were similar across the groups; CC:CT:TT was 26.9%:51.0%:22.1% in blood donors, 25.9%:52.0%:22.1% in matched control subjects, 27.4%:49.9%:22.7% in patients with CAD, and 29.2%:49.2%:21.6% in patients with MI. The lack of association persisted also after adjustment for the presence of conventional cardiovascular risk factors. In addition, no significant differences were found between genotype distributions of control subjects and selected subgroups of patients with CAD or MI. Conclusion These findings indicate that, in the sample of patients examined in this study, the −159C/T polymorphism of the CD14 gene is not related to CAD or MI. (Am Heart J 2002;143:971-6.)     

Acute myocardial infarction in the young— The University of Michigan experience

Background The purpose of this study was to assess frequency, risk factors, treatment, and complications of very young patients with acute myocardial infarction (MI) at the University of Michigan Medical Center (UMMC). Methods From a database of 976 consecutive patients admitted to the UMMC with acute MI between 1995 and 1998, we compared care and outcomes of patients divided into 3 age categories: <46 years, 46-54 years, and >54 years. Risk factors, presenting symptoms, type of MI, management, complications, and hospital outcomes of the 3 groups were evaluated. Results Young patients represented >10% of all patients with acute MI, and >25% of these individuals were women, a number considerably higher than seen in previous studies. This group of young patients was more likely to have Q-wave MI and risk factors such as family history and tobacco use and less likely to have a history of angina. Although all 3 groups received similar inpatient treatment, there was more attention paid to risk factor modification such as smoking cessation and referral to cardiac rehabilitation in younger individuals. Young patients had fewer in-hospital complications and a lower mortality rate. Conclusions At the University of Michigan, >1 in 10 with acute MI is <46 years old. Data suggest that current management and aggressive risk factor modification are quite good in this particular group, and overall the mortality rate is very low. (Am Heart J 2002;143:56-62.)     

Left ventricular remodeling in the first year after acute myocardial infarction and the predictive value of N-terminal pro brain natriuretic peptide

Background Left ventricular (LV) remodeling after myocardial infarction (MI) has received much attention because of its severe impact on morbidity and mortality rates. However, the incidence and extent of LV remodeling in a modern infarct population who were offered antiremodeling treatment in compliance with daily clinical practice is unknown. The purpose of this study was to clarify this issue and to evaluate the predictive value of N-terminal pro brain natriuretic peptide (NT-proBNP). Methods Forty-two patients with a first transmural MI were examined after 1 week, 1 month, 3 months, 6 months, and 1 year with blood samples and magnetic resonance imaging. Results In 12 patients (29%), LV end-diastolic volume index (LVEDVI) and LV end-systolic volume index (LVESVI) increased by 24% and 22% (P <.0001; P = .01). In 12 patients (29%), LVEDVI and LVESVI decreased by 19% and 23% (P <.0001; P = .0005), whereas the remaining 18 patients (43%) had stable conditions regarding these LV measures. LV ejection fraction at baseline was significantly reduced in all patient categories but was unchanged over time. Elevated NT-proBNP level at baseline was identified as an independent predictor of increase in LVEDVI during follow-up examination (P = .007). A baseline level of NT-proBNP >115 pmol/L identified patients who later had LV dilatation develop with a sensitivity and specificity of 89% and 68% (area under curve = 0.77). Conclusion In this 1-year follow-up study of patients with a first transmural MI, approximately 30% had significant increments develop in LVEDVI and LVESVI, and LV ejection fraction remained unchanged. Patients in whom LV dilatation developed could be identified early after the MI with elevated plasma levels of NT-proBNP. (Am Heart J 2002;143:696-702.)