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

Correlation between endothelial dysfunction and occurrence of no-reflow in patients undergoing post-thrombolysis early invasive percutaneous intervention for ST-elevation myocardial infarction

Background

Endothelial dysfunction and no-reflow share microcirculatory obstruction as a common pathophysiological mechanism. This study evaluated the relationship between systemic peripheral endothelial dysfunction assessed by flow-mediated dilatation (FMD) of the brachial artery and no-reflow in patients with ST-segment elevation myocardial infarction (STEMI) who received successful fibrinolysis.

Results

This study included 150 patients managed by the percutaneous coronary intervention (PCI) after successful fibrinolysis. Patients were divided according to coronary angiographic success into normal flow versus no-reflow groups. According to FMD measured through brachial artery ultrasound, patients were divided based on their endothelial function into endothelial dysfunction versus normal endothelial function. No-reflow occurred in 44 patients (29.3%). No-reflow patients had longer pain to door time (6.52 ± 1.82 vs 5.19 ± 1.85 h), more Killip class II (36.4% vs 16%, p = 0.006), and lower FMD (7.26 ± 1.92 vs 8.23 ± 2.76%, p = 0.036). Also, they showed more endothelial dysfunction; however, this difference was statistically nonsignificant (97.7% vs 87.7%, p = 0.055). One hundred and thirty-six patients (90.7%) had endothelial dysfunction. They were older (57.51 ± 5.92 vs 50.86 ± 4.55 years, p value ≤ 0.001), more smokers (41.2% vs 14.3%, p = 0.04). Patients with normal endothelial function had a more myocardial blush grade (MBG) 3 (78.6% vs 26.5%, p value = 0.001) in comparison with more MBG 2 in those with endothelial dysfunction (41.9% vs 14.3%, p value = 0.001). Endothelial dysfunction patients had nonsignificant more no-reflow (31.6% vs 7.1%, p-value: 0.06). There was a significant weak positive correlation between thrombolysis in myocardial infarction (TIMI) flow and FMD (r = 0.174, p = 0.033) and a significant moderate positive correlation between MBG and FMD (r = 0.366, p < 0.001). Patients with TIMI I flow had significantly lower FMD compared with patients with TIMI II and TIMI III flow post-PCI. FMD ≤ 6% could predict post-procedural TIMI I flow.

Conclusions

In STEMI patients who underwent PCI within 24 h after successful fibrinolysis, those who had no-reflow showed worse peripheral systemic endothelial function as they had lower brachial artery FMD. Also, FMD showed a significant positive correlation with the post-procedural angiographic flow (TIMI flow and MBG). FMD ≤ 6% could predict TIMI I flow.

Accuracy of Resolution of ST-Segment Elevation in Electrocardiogram to Determine the Patency of Infarct-Related Artery

Introduction: There is very limited data comparing the accuracy of ECG to angiography in predicting reperfusion status. In this study, we will determine the accuracy of ECG change i.e. resolution of ST-segment elevation in predicting infarct-related artery (IRA) patency after thrombolysis in patients with ST-segment elevated myocardial infarction (STEMI), in comparison to angiography.

Methods: Three hundred and forty-one (n = 341) patients with acute STEMI received streptokinase, a thrombolytic agent within 12 hours of symptoms, and were enrolled in the study via consecutive convenient non-probability sampling. ECG was recorded as soon as the patient arrived in the emergency unit of cardiology. Subsequent ECG was recorded three hours after the administration of streptokinase to look for resolution of ST-segment elevation. ST-segment resolution was classified as greater/equal to 50% resolved or less than 50% resolved. Coronary angiography was performed within 24 hours of hospitalization and flow in the IRA was assessed.

Results: The most common site of myocardial infarction (MI) was the anterior wall (50.1%) and the commonest artery involved was the left anterior descending artery (44.2%). On ECG, ST-resolution of more than 50% was found in 242 (70.9%) participants. Thrombolysis in MI (TIMI) grade III flow in angiography was found in 211 (61.8%) participants. The sensitivity and specificity of ST-resolution to detect TIMI grade III flow was 94.79% and 67.69%, respectively, while accuracy was 84.46%.

Conclusion: ST-resolution on ECG after streptokinase can predict IRA patency on coronary angiography with moderate to good accuracy. ECG can assist in predicting the impact of streptokinase early in the course of management and give an option of monitoring patient prognosis with a non-invasive test in patients not comfortable with angiography.

Clinical Implications of ST-Segment Non-Resolution after Thrombolysis for Myocardial Infarction

Failed reperfusion after thrombolytic therapy for acute myocardial infarction is common and signifies a poor prognosis. We investigated the clinical consequences of non-resolution of the ST segment after thrombolytic therapy for acute ST-elevation myocardial infarction, in 85 consecutive patients admitted to a coronary care unit lacking rapid access to angioplasty. Failed thrombolysis was defined as <50% ST-segment resolution 180 minutes after the start of thrombolytic treatment. Outcomes were measured in terms of in-hospital adverse events, length of hospital stay, and mortality at 6 weeks and 1 year. Thrombolysis was successful, in terms of ST-segment resolution, in 45 patients (53%). After adjustment for other factors, ST resolution was the only independent predictor of an uncomplicated recovery in hospital (odds ratio 6.8, 95% confidence interval 2.3 to 19.9; P<0.001). At 6 weeks and 1 year, overall mortality was lower in the ST resolution group, though these differences became non-significant on multivariate analysis. In patients who survived to hospital discharge, median length of stay was greater in successfully thrombolysed patients (9 days versus 8 days) despite their lower rate of complications. ST-segment resolution is a useful marker of successful thrombolysis and relates to clinical outcome. If assessed routinely it might assist, along with other clinical markers, in the identification of low-risk patients who can be discharged early.

A comparison of rescue and primary percutaneous coronary interventions for acute ST elevation myocardial infarction

Objective

To perform a comparative analysis of in-hospital results obtained from patients with acute ST elevation myocardial infarction (STEMI), who underwent rescue or primary percutaneous coronary intervention (PCI). The aim is to determine rescue PCI as a practical option for patients with no immediate access to primary PCI.

Methods

From the Cardiology PCI Clinic of the National Hospital of Sri Lanka (NHSL), we selected all consecutive patients presenting with acute STEMI </ = 24 h door-to-balloon delay for primary PCI and </ = 72 h door-to-balloon delay, (90 min after failed thrombolysis) for rescue PCI, from March 2013 to April 2015 and their in-hospital results were analyzed, comparing rescue and primary PCI patients.

Results

We evaluated 159 patients; 78 underwent rescue PCI and 81 underwent primary PCI. The culprit left anterior descending (LAD) vessel (76.9% vs. 58.8%; P = 0.015) was more prevalent in rescue than in primary patients. Thrombus aspiration was less frequent in rescue group (19.2% vs. 40.7%; p = 0.004). The degree of moderate-to-severe left ventricular dysfunction reflected by the ejection fraction <40% (24.3% vs. 23.7%; P = 0.927) and prevalence of multivessel disease (41.0% vs. 43.8%; P = 0.729) revealed no significant difference. Coronary stents were implanted at similar rates in both strategies (96.2% vs. 92.6%; P = 0.331). Procedural success (97.4% vs. 97.5%; P = 0.980) and mortality rates (5.1% vs. 3.8%; P = 0.674), were similar in the rescue and primary groups.

Conclusion

In-hospital major adverse cardiac events (MACE) are similar in both rescue and primary intervention groups, supporting the former as a practical option for patients with no immediate access to PCI facilities.

Reperfusion ventricular arrhythmia bursts identify larger infarct size in spite of optimal epicardial and microvascular reperfusion using cardiac magnetic resonance imaging

AIMS

Ventricular arrhythmia (VA) bursts following recanalisation in acute ST-elevation myocardial infarction (STEMI) are related to larger infarct size (IS). Inadequate microvascular reperfusion, as determined by microvascular obstruction (MVO) using cardiac magnetic resonance imaging (CMR), is also known to be associated with larger IS. This study aimed to test the hypothesis that VA bursts identify larger infarct size in spite of optimal microvascular reperfusion.

METHODS

All 65 STEMI patients from the Maastricht ST elevation (MAST) study with brisk epicardial flow (TIMI 3), complete ST recovery post-percutaneous coronary intervention and early CMR were included. Using 24-hour Holter registrations from the time of admission, VA bursts were identified against subject-specific Holter background VA rates using a statistical outlier method. MVO and final IS were determined using delayed enhancement CMR.

RESULTS

MVO was present in 37/65 (57%) of patients. IS was significantly smaller in the group without MVO (median 9.4% vs. 20.5%; p < 0.001). IS in the group with MVO did not differ depending on VA burst ( n = 28/37; median 20.8% vs. 19.7%; p = 0.64). However, in the group without MVO, VA burst was associated with significantly larger IS ( n = 17/28; median 10.5% vs. 4.1%; p = 0.037). In multivariable analyses, VA burst as well as anterior infarct location remained independent predictors of larger infarct size.

CONCLUSION

In the presence of suboptimal reperfusion with MVO by CMR, VA burst does not further define MI size. However, with optimal TIMI 3 reperfusion and optimal microvascular perfusion (i.e. no MVO), VA burst is associated with larger IS, indicating that VA burst is a marker of additional cell death.

The Prehospital Sepsis Project: out-of-hospital physiologic predictors of sepsis outcomes

INTRODUCTION

Severe sepsis and septic shock are common, expensive and often fatal medical problems. The care of the critically sick and injured often begins in the prehospital setting; there is limited data available related to predictors and interventions specific to sepsis in the prehospital arena. The objective of this study was to assess the predictive effect of physiologic elements commonly reported in the out-of-hospital setting in the outcomes of patients transported with sepsis.

METHODS

This was a cross-sectional descriptive study. Data from the years 2004-2006 were collected. Adult cases (≥18 years of age) transported by Emergency Medical Services to a major academic center with the diagnosis of sepsis as defined by ICD-9-CM diagnostic codes were included. Descriptive statistics and standard deviations were used to present group characteristics. Chi-square was used for statistical significance and odds ratio (OR) to assess strength of association. Statistical significance was set at the .05 level. Physiologic variables studied included mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR) and shock index (SI).

RESULTS

Sixty-three (63) patients were included. Outcome variables included a mean hospital length of stay (HLOS) of 13.75 days (SD = 9.97), mean ventilator days of 4.93 (SD = 7.87), in-hospital mortality of 22 out of 63 (34.9%), and mean intensive care unit length-of-stay (ICU-LOS) of 7.02 days (SD = 7.98). Although SI and RR were found to predict intensive care unit (ICU) admissions, [OR 5.96 (CI, 1.49-25.78; P = .003) and OR 4.81 (CI, 1.16-21.01; P = .0116), respectively] none of the studied variables were found to predict mortality (MAP <65 mmHg: P = .39; HR >90: P = .60; RR >20 P = .11; SI >0.7 P = .35).

CONCLUSIONS

This study demonstrated that the out-of-hospital shock index and respiratory rate have high predictability for ICU admission. Further studies should include the development of an out-of-hospital sepsis score.

Anaemia and prognosis in acute coronary syndromes: a systematic review and meta-analysis

OBJECTIVE

This meta-analysis was conducted to summarize the association between anaemia and outcomes in patients with acute coronary syndromes (ACS).

METHODS

MEDLINE®, Cochrane Library, OVID and EMBASE databases were searched to identify studies that examined the effect of anaemia on mortality or other adverse events (heart failure, cardiogenic shock or major bleeding).

RESULTS

Nineteen studies met the final inclusion criteria (total number of patients 241 293). The risks of shortterm mortality (odds ratio [OR] 2.77; 95% confidence interval [CI] 2.09, 3.65), long-term mortality (OR 2.03; 95% CI 1.52, 2.71), heart failure (OR 1.96; 95% CI 1.47, 2.62), cardiogenic shock (OR 1.95; 95% CI 1.04, 2.64) and major bleeding (OR 4.28; 95% CI 1.05, 17.14) were increased in patients with anaemia, compared with patients without anaemia. Anaemia was also associated with a higher risk of mortality (adjusted hazard ratio 1.49, 95% CI 1.24, 1.79).

CONCLUSIONS

These study findings suggest that anaemia can be used to identify patients with ACS who are at a high risk of death or adverse events, and it may become a promising risk stratification factor in ACS.

Value of early risk stratification using hemoglobin level and neutrophil-to-lymphocyte ratio in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention

Complete blood count is the most widely available laboratory datum in the early in-hospital period after ST-elevation myocardial infarction (STEMI). We assessed the clinical utility of the combined use of hemoglobin (Hb) level and neutrophil-to-lymphocyte ratio (N/L) for early risk stratification in patients with STEMI. We analyzed 801 consecutive patients with STEMI treated with primary percutaneous coronary intervention (PCI) within 12 hours of onset of symptoms. Patients with cardiogenic shock or underlying malignancy were excluded, and 739 patients (63 ± 13 years, 74% men) were included in the final analysis. Patients were categorized into 3 groups using the median value of N/L (3.86) and the presence of anemia (Hb <13 mg/dl in men and <12 mg/dl in women); group I had low N/L and no anemia (n = 272), group II had low N/L and anemia, or high N/L and no anemia (n = 331), and group III had high N/L and anemia (n = 136). There were significant differences on clinical outcomes during 6-month follow-up among the 3 groups. Prognostic discriminatory capacity of combined use of Hb level and N/L was also significant in high-risk subgroups such as patients with advanced age, diabetes mellitus, multivessel coronary disease, low ejection fraction, and even in those having higher mortality risk based on Thrombolysis In Myocardial Infarction risk score. In a Cox proportional hazards model, after adjusting for multiple covariates, group III had higher mortality at 6 months (hazard ratio 5.6, 95% confidence interval 1.1 to 27.9, p = 0.036) compared to group I. In conclusion, combined use of Hb level and N/L provides valuable timely information for early risk stratification in patients with STEMI undergoing primary PCI.

Does ST resolution achieved via different reperfusion strategies (fibrinolysis vs percutaneous coronary intervention) have different prognostic meaning in ST-elevation myocardial infarction? A systematic review

OBJECTIVE

We perform a systematic review to discern if ST resolution achieved via percutaneous coronary intervention (PCI) has a different meaning to that achieved via fibrinolysis.

BACKGROUND

Resolution of ST-segment elevation in acute myocardial infarction has been widely used as a surrogate for treatment success. A recent randomized study suggested that after primary PCI, the prognostic significance of ST resolution may have been overemphasized.

METHODS

Using the MEDLINE, COCHRANE, EMBASE, and PUBMED databases to search for the relevant papers, we analyze the data with a new ST-resolution score. ST-resolution groups of <30%, 30% to < 70%, and ≥ 70% are given scores of 1, 2, and 3 respectively, whereas ST-resolution groups reported as < 50% are scored as 1.5, and ≥ 50% scored as 2.5.

RESULTS

We identify 18 fibrinolysis cohorts (32,341 patients) and 5 PCI cohorts (1,913 patients). The mean ST-resolution score weighted for the number of patients in each cohort is 1.87 ± 0.15 for PCI and 1.66 ± 0.20 for fibrinolysis (P < .001). The raw combined 30-day mortality is 4.9% with fibrinolysis and 4.3% with PCI (P = .452 by Poisson regression). There is a linear relationship with lower 30-day mortality associated with higher ST-resolution score. The regression line for the PCI cohorts almost overlaps with that from the fibrinolysis cohorts. On multivariate regression, only ST-resolution score is significant in predicting 30-day mortality. When tested, the interaction term (treatment group × ST resolution score) is never a significant predictor (P > .25 in all models).

CONCLUSION

ST resolution after different reperfusion therapies has similar prognostic meaning.

Prognostic value of lead V1 ST elevation during acute inferior myocardial infarction

BACKGROUND

Lead V(1) directly faces the right ventricle and may exhibit ST elevation during an acute inferior myocardial infarction when the right ventricle is also involved. Leads V(1) and V(3) indirectly face the posterolateral left ventricle, and ST depression ("mirror-image" ST elevation) in V(1) through V(3) may reflect concomitant posterolateral infarction. The prognostic significance of V(1) ST elevation during an acute inferior myocardial infarction may therefore be dependent on V(3) ST changes.

METHODS AND RESULTS

In 7967 patients with acute inferior myocardial infarction in the Hirulog and Early Reperfusion or Occlusion-2 (HERO-2) trial, V(1) ST levels were analyzed with adjustment for lead V(3) ST level for predicting 30-day mortality. V(1) ST elevation at baseline, analyzed as a continuous variable, was associated with higher mortality. Unadjusted, each 0.5-mm-step increase in ST level above the isoelectric level was associated with approximately 25% increase in 30-day mortality; this was true whether V(3) ST depression was present or not. The odds ratio for mortality was 1.21 (95% confidence interval, 1.07 to 1.37) after adjustment for inferolateral ST elevation and clinical factors and 1.24 (95% confidence interval, 1.09 to 1.40) if also adjusted for V(3) ST level. In contrast, lead V(1) ST depression was not associated with mortality after adjustment for V(3) ST level. V(1) ST elevation >or=1 mm, analyzed dichotomously in all patients, was associated with higher mortality. The odds ratio was 1.28 (95% confidence interval, 1.01 to 1.61) unadjusted, 1.51 (95% confidence interval, 1.19 to 1.92) adjusted for V(3) ST level, and 1.35 (95% confidence interval, 1.04 to 1.76) adjusted for ECG and clinical factors. Persistence of V(1) ST elevation >or=1 mm 60 minutes after fibrinolysis was associated with higher mortality (10.8% versus 5.5%, P=0.001).

CONCLUSIONS

V(1) ST elevation identifies patients with acute inferior myocardial infarction who are at higher risk.

ST-segment resolution prior to primary percutaneous coronary intervention is a poor indicator of coronary artery patency in patients with acute myocardial infarction

BACKGROUND

The prognostic value of ST-segment resolution (STR) after initiation of reperfusion therapy has been established by various studies conducted in both the thrombolytic and mechanic reperfusion era. However, data regarding the value of STR immediately prior to primary percutaneous coronary intervention (PCI) to predict infarct-related artery (IRA) patency remain limited. We investigated whether STR prior to primary PCI is a reliable, noninvasive indicator of IRA patency in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

The study population consisted of STEMI patients who underwent primary PCI at our institution between 2000 and 2007. STR was analyzed in 12-lead electrocardiograms recorded at first medical contact and immediately prior to primary PCI and defined as complete (> or =70%), partial (70%- 30%), or absent (<30%).

RESULTS

In 1253 patients with a complete data set, STR was inversely related to the probability of impaired preprocedural flow (P(for trend) < 0.001). Although the sensitivity of incomplete (<70%) STR to predict a Thrombolysis in Myocardial Infarction (TIMI) flow of <3 was 96%, the specificity was 23%, and the negative predictive value of incomplete STR to predict normal coronary flow was only 44%.

CONCLUSIONS

This study establishes the correlation between STR prior to primary PCI and preprocedural TIMI flow in STEMI patients treated with primary PCI. However, the negative predictive value of incomplete STR for detection of TIMI-3 flow is only 44% and therefore should not be a criterion to refrain from immediate coronary angiography in STEMI patients.

Early dynamic risk stratification with baseline troponin levels and 90-minute ST-segment resolution to predict 30-day cardiovascular mortality in ST-segment elevation myocardial infarction: analysis from CLopidogrel as Adjunctive ReperfusIon TherapY (CLARITY)-Thrombolysis in Myocardial Infarction (TIMI) 28

BACKGROUND

Troponin is the preferred biomarker for risk stratification in non-ST elevation ACS. The incremental prognostic use of the initial magnitude of troponin elevation and its value in conjunction with ST-segment resolution (STRes) in ST elevation myocardial infarction (STEMI) is less well defined.

METHODS

Troponin T (TnT) was measured in 1,250 patients at presentation undergoing fibrinolysis for STEMI in CLARITY-TIMI 28. ST-segment resolution was measured at 90 minutes. Multivariable logistic regression was used to examine the independent association between TnT levels, STRes, and 30-day cardiovascular (CV) mortality.

RESULTS

Patients were classified into undetectable TnT at baseline (n = 594), detectable but below the median of 0.12 ng/mL (n = 330), and above the median (n = 326). Rates of 30-day CV death were 1.5%, 4.5%, and 9.5%, respectively (P < .0001). Compared with those with undetectable levels and adjusting for baseline factors, the odds ratios for 30-day CV death were 4.56 (1.72-12.08, P = .002) and 5.81 (2.29-14.73, P = .0002) for those below and above the median, respectively. When combined with STRes, there was a significant gradient of risk, and in a multivariable model both baseline TnT (P = .004) and STRes (P = .003) were significant predictors of 30-day CV death. The addition of TnT and STRes to clinical risk factors significantly improved the C-statistic (from 0.86 to 0.90, P = .02) and the integrated discriminative improvement (7.1% increase) (P = .0009).

CONCLUSIONS

Baseline TnT and 90-minute STRes are independent predictors of 30-day CV death in patients with STEMI. Use of these 2 simple, readily available tools can aid clinicians in early risk stratification.

aVR ST elevation: an important but neglected sign in ST elevation acute myocardial infarction

AIM

This study evaluated the prognostic implications of aVR ST elevation during ST elevation acute myocardial infarction (AMI).

METHODS AND RESULTS

The Hirulog and Early Reperfusion/Occlusion-2 study randomized 17 073 patients with acute ST elevation AMI within 6 h of symptom onset to receive either bivalirudin or heparin, in addition to streptokinase and aspirin. The treatments had no effect on the primary endpoint of 30-day mortality. Electrocardiographic recordings were performed at randomization and at 60 min after commencing streptokinase. aVR ST elevation > or =1 mm was associated with higher 30-day mortality in 15 315 patients with normal intraventricular conduction regardless of AMI location (14.7% vs. 11.2% for anterior AMI, P = 0.0045 and 16.0% vs. 6.4% for inferior AMI, P < 0.0001). After adjusting for summed ST elevation and ST depression in other leads, associations with higher mortality were found with aVR ST elevation of > or =1.5 mm for anterior [odds ratio 1.69 (95% CI 1.16 to 2.45)] and of > or =1 mm for inferior AMI [odds ratio 2.41 (95% CI 1.76 to 3.30)]. There was a significant interaction between aVR ST elevation and infarct location. Thirty-day mortality was similar with anterior and inferior AMI when aVR ST elevation was present (11.5% vs. 13.2%, respectively, P = 0.51 with 1 mm and 23.5% vs. 22.5% respectively, P = 0.84 with > or = 1.5 mm ST elevation). After fibrinolytic therapy, resolution of ST elevation in aVR to <1 mm was associated with lower mortality, while new ST elevation > or =1 mm was associated with higher mortality.

CONCLUSION

aVR ST elevation is an important adverse prognostic sign in AMI.

Impact of anemia on clinical outcomes of patients with ST-segment elevation myocardial infarction in relation to gender and adjunctive antithrombotic therapy (from the HORIZONS-AMI trial)

The aim of this study was to assess the impact of baseline anemia on the outcomes of patients with ST elevation myocardial infarctions who underwent primary percutaneous coronary intervention in relation to contemporary adjunctive antithrombotic therapy and gender. In the Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial, patients were randomized to bivalirudin alone or to unfractionated heparin plus a glycoprotein IIb/IIIa inhibitor before primary percutaneous coronary intervention. Outcomes were assessed at 30 days and 1 year according to anemia and gender. Baseline anemia was present in 331 of 3,153 patients (10.5%). Patients with versus without baseline anemia had a more than twofold increase in major bleeding at 30 days (13.5% vs 6.7%, p <0.0001) and at 1 year (14.8% vs 7.2%, p <0.0001), an association that on multivariate analysis was independent of gender. Mortality was significantly higher in men with versus without baseline anemia (4.6% vs 1.8% at 30 days, p = 0.003; 8.9% vs 3.0% at 1 year, p <0.0001) but not in women (5.3% vs 3.6% at 30 days, p = 0.42; 7.5% vs 5.9% at 1 year, p = 0.54). On multivariate analysis, anemia independently predicted 1-year all-cause mortality in men but not in women. Bivalirudin compared with unfractionated heparin plus a glycoprotein IIb/IIIa inhibitor resulted in twofold lower rates of all-cause and cardiac mortality and major bleeding in patients without but not in those with baseline anemia. In conclusion, baseline anemia was associated with increased major bleeding and death in patients with ST elevation myocardial infarctions who underwent primary PCI but was a stronger predictor of early and late mortality in men than in women. Paradoxically, in this post hoc analysis, the reductions in major bleeding and mortality in ST elevation myocardial infarction afforded by bivalirudin occurred primarily in patients without baseline anemia.

Unexpected mortality in patients discharged from the emergency department following an episode of nontraumatic chest pain

BACKGROUND

Chest pain is the second most common presenting complaint seen in the emergency department. Following evaluation in the emergency department, many of these patients are discharged with a diagnosis of nonspecific chest pain. Our hypothesis is that this group of patients has a high prevalence of ischaemic heart disease.

METHODS

This was a prospective follow-up study of mortality in 786 patients who presented to an emergency department in the UK with an episode of nontraumatic chest pain and were discharged without further inpatient assessment. Observed mortality was compared with expected mortality in age-matched and sex-matched local population.

RESULTS

The observed mortality of the study group was consistently higher than expected throughout the study period. The 5-year mortality rates for men and women under the age of 65 years were more than double the expected rates for the local population [relative risk of 2.1 (95% confidence interval: 1.4-2.8) and 2.6 (1.4-3.8), respectively]. This increase was less marked in male and female patients aged 65 years or more [relative risk of 1.2 (0.9-1.5) and 1.5 (1.2-1.8), respectively]. Ischaemic heart disease accounted for almost 50% of male deaths in the study group. This compared with an expected rate of less than 30% of male deaths in the local population. An excess of cardiac deaths was not seen in women.

INTERPRETATION

Patients discharged from the emergency department following an episode of acute chest pain have significantly reduced 5-year survival. We conclude that further evaluation of this group to establish the prevalence of risk factors is important to support the strategic implementation of appropriate prevention programmes.

Limited prognostic value of noninvasive assessment of reperfusion by continuous vectorcardiography in an unselected cohort of patients with acute ST-elevation myocardial infarction treated with thrombolysis

AIMS

We studied the prognostic value of different reperfusion criteria of short-term continuous vectorcardiography (VCG) in an unselected cohort of 400 patients with ST-elevation myocardial infarction, treated at 4 coronary care units in Stockholm, Sweden, between 1999 and 2002. The main outcome measure was 1-year mortality.

RESULTS

Of 400 study patients, 41 (10.2%) died within 1 year. One-year mortality in patients without reperfusion at 90 minutes, defined as ST resolution below 50% on VCG, was 11.6% compared with 9.0% in patients with reperfusion, (P = 0.4). Ninety-eight (24.5%) patients underwent intervention before discharge and percutaneous coronary intervention or coronary artery bypass grafting or both during the index admission. Percutaneous coronary intervention or coronary artery bypass grafting was related to improved 1-year survival (97 +/- 2% vs 87 +/- 2%, P = .0076). ST-vector magnitude resolution at 90 minutes was lower in patients who underwent intervention (P = .045). None of the reperfusion criteria of VCG was significantly associated with 1-year mortality.

CONCLUSION

Our results show that noninvasive assessment of reperfusion by continuous VCG has limited prognostic value in unselected patients treated with thrombolysis because of ST-elevation myocardial infarction when subsequent revascularizations are performed. However, VCG might be useful in selecting patients for coronary angiography with subsequent revascularization.

ST-segment recovery and prognosis in patients with ST-elevation myocardial infarction reperfused by prehospital combination fibrinolysis, prehospital initiated facilitated percutaneous coronary intervention, or primary percutaneous coronary intervention

Complete ST-segment recovery (STR) is associated with favorable prognosis in ST-elevation myocardial infarction (STEMI). The optimal reperfusion strategy in patients presenting soon after symptom onset is still a matter of debate. STR for patients treated by prehospital combination fibrinolysis or prehospital initiated facilitated percutaneous coronary intervention (PCI) compared with primary PCI has not been assessed. In the Leipzig Prehospital Fibrinolysis Study, patients with STEMI (symptoms <6 hours) were randomized to prehospital combination fibrinolysis (1/2 dose reteplase + abciximab; n = 82, group A) or prehospital initiated facilitated PCI (n = 82, group B). Further, a control group of patients with primary PCI (n = 136, group C) was prospectively assessed. STR at 90 minutes was analyzed by blinded observers as percent resolution. Categorization was performed as complete resolution (>70%), intermediate resolution (70% to 30%), or no resolution (<30%). The percentage of patients with complete STR was highest in group B with 80% versus 52% in group A and 52% in group C (p <0.001, B vs A and C, p = NS; A vs C). Complete STR resulted in lower event rates for the combined clinical end point of death, myocardial reinfarction, and stroke compared with intermediate and no STR in groups A (complete 9.8%, intermediate 23.8%, no STR 36.8%, p = 0.04), B (7.7%, 18.2%, and 50.0%, p = 0.01), and C (8.6%, 18.4%, and 42.9%, p <0.001). In conclusion, prehospital initiated facilitated PCI results in the highest percentage of complete STR compared with prehospital combination fibrinolysis or primary PCI. In addition, STR has been confirmed to predict prognosis in timely optimized reperfusion strategies.

Risk Stratification of Patients With Acute Anterior Myocardial Infarction and Right Bundle-Branch Block

BACKGROUND

Patients with an acute anterior ST-segment elevation myocardial infarction and right bundle-branch block (RBBB) have a high mortality risk, which may be stratified by early ECG changes.

METHODS AND RESULTS

In the Hirulog Early Reperfusion Occlusion (HERO-2) trial, 17 073 patients with acute myocardial infarction (AMI) within 6 hours of symptom onset were treated with streptokinase and randomized to receive bivalirudin or heparin. There was no difference in the primary end point of 30-day mortality. ECGs were recorded at randomization and 60 minutes after fibrinolytic therapy was begun. The 30-day mortality rate was 31.6% in the 415 patients with RBBB and anterior AMI at randomization and 33% in the 100 patients who developed new RBBB at 60 minutes from normal baseline conduction accompanying an anterior AMI. An increase in QRS duration by 20-ms increments was associated with increasing 30-day mortality rate in both RBBB groups on multivariable analyses with covariates of age, Killip class, systolic blood pressure, pulse, and prior infarction. Patients with QRS duration > or = 160 ms had higher 30-day mortality rate than those with QRS duration < 160 ms (37.2% versus 27.2%, P = 0.03, and 46.2% versus 24.5%, P = 0.025, in the 2 groups, respectively). For the patients with RBBB and anterior MI at randomization, RBBB resolved at 60 minutes in 40 patients, but 30-day mortality rate was unchanged. For those with persisting RBBB at 60 minutes, 30-day mortality rate was lower if ST-segment elevation had resolved by > or = 50% (20.4% versus 35.3%, P = 0.006).

CONCLUSIONS

In patients with anterior AMI and RBBB, increasing QRS duration is associated with increasing 30-day mortality. Early ST-segment resolution after fibrinolytic therapy despite persisting RBBB is associated with lower mortality rate.

Prognostic significance of admission heart failure in patients with non-ST-elevation acute coronary syndromes (from the Canadian Acute Coronary Syndrome Registries)

We evaluated the in-hospital and 1-year outcomes and predictors of admission heart failure in patients with non-ST-elevation acute coronary syndromes (NSTE-ACSs) without previous heart failure. We analyzed 4,825 patients with NSTE-ACS without a history of congestive heart failure who were included in the multicenter Canadian ACS Registries. Patients in Killip's class II/III on admission (n = 559, 11.6%) were compared with patients in Killip's class I. Patients with heart failure on admission were older (72 [64, 79] vs 64 [54, 73] years, p < 0.0001), with higher baseline creatinine levels (96 vs 88 mmol/dl, p <0.0001), more diabetes (32.2% vs 22.8%, p < 0.0001), hypertension (58% vs 52.4%, p = 0.014), previous myocardial infarction (MI; 38.9% vs 30.3%, p < 0.0001), previous stroke (13.5% vs 7.4%, p < 0.0001), and had more ST depression on admission (27.7% vs 17.3%, p < 0.0001). In-hospital treatment was similar except for a lower rate of aspirin therapy and fewer coronary interventions. Crude event rates were significantly higher in patients with heart failure (in-hospital death 3.6% vs 1.1%, p < 0.0001; death or MI 7.9% vs 4.7%, p = 0.0011; stroke 1.1% vs 0.4%, p = 0.03). One-year event rates were also higher in patients with heart failure (death 14.6% vs 4.4%, p < 0.0001; MI 9.3% vs 6.6%, p = 0.03; death or MI 21.5% vs 10.3%, p < 0.0001). Variables independently associated with heart failure were age (odds ratio 1.57, 95% confidence interval 1.43 to 1.73), diabetes mellitus (odds ratio 1.53, 95% confidence interval 1.24 to 1.89), admission ST depression (odds ratio 1.52, 95% confidence interval 1.22 to 1.90), previous MI, and baseline creatinine. Heart failure on admission was an independent predictor of in-hospital death, death or MI, and stroke and of 1-year death and death or MI. In conclusion, in patients with NSTE-ACS, heart failure on admission is associated with increased short- and long-term rates of death and MI.

The 12-lead electrocardiogram as a predictive tool of mortality after acute myocardial infarction: current status in an era of revascularization and reperfusion

Many recently published studies established the admission electrocardiogram as an excellent source of prognostic information in patients presenting with acute myocardial infarction. Using our search criteria, we identified a large number of articles but selected only the most relevant in each category. The best predictors of increased short-term mortality are ventricular tachycardia (odds ratio [OR] 6.1, 95% CI 4.6-8.3), ST-segment deviations (OR 5.1, 95% CI 4.6-8.3), high-degree atrioventricular block (OR 5.1, 95% CI 2.1-11.9), and long QRS duration (OR 4.2, 95% CI 1.8-10.4). For increased long-term mortality, the best predictors were ST-segment depression (OR 5.7, 95% CI 2.8-11.6), ST-segment elevation (OR 3.3, 95% CI 2.1-5.1), and left bundle-branch block (OR 2.8, 95% CI 1.8-4.3). In addition, our review discusses electrocardiographic markers of poor outcome that were not independent risk factors on multivariate analysis, conflicting findings, and knowledge gaps that can help plan future research efforts.

Grade 3 ischemia on admission and absence of prior beta-blockade predict failure of ST resolution following thrombolysis for anterior myocardial infarction

BACKGROUND

ST segment resolution (STR) is a strong predictor of outcome following thrombolysis. If failure of STR could be predicted on admission, better selection of treatment may be possible. Among patients given reperfusion, those with terminal QRS distortion (grade 3 ischemia) have larger infarcts, but the mechanism underlying this association is unclear. Whether grade 3 ischemia on admission can predict STR is unknown.

METHODS

We studied 180 consecutive patients given thrombolysis for a first anterior acute myocardial infarction (AMI). Multiple variables available on admission were analyzed as predictors of STR at 1, 2, and 24 h and as predictors of the need for rescue percutaneous coronary intervention (PCI).

RESULTS

Multivariate predictors of failure of STR were: for 1 h: extent of ST elevation (OR: 1.09 [1.01-1.18]); for 2 h: no previous use of beta-blockers (OR: 4.71 [1.56-13.98]) and grade 3 ischemia (OR: 6.77 [3.27-13.95]); for 24 h: previous use of aspirin (OR: 6.70 [1.31-34.01]) and grade 3 ischemia (OR: 29.44 [7.30-118.1]). Grade 3 ischemia had a strong positive predictive value for failure of STR at 1 and 2 h and was the strongest predictor of the need for rescue PCI.

CONCLUSIONS

Grade 3 ischemia on admission is the strongest independent predictor of failure to achieve myocardial reperfusion after thrombolysis. This association may underlie the larger infarcts associated with grade 3 ischemia. Other predictors of reperfusion failure are the extent of ST segment elevation, prior use of aspirin and no prior use of beta-blockers.

Effect of clopidogrel plus aspirin on tissue perfusion and coronary flow in patients with ST-segment elevation myocardial infarction: a new reperfusion strategy

BACKGROUND

Current reperfusion strategies may fail to achieve optimal tissue perfusion in ST-elevation myocardial infarction (STEMI). We investigated the effect of clopidogrel plus aspirin on tissue perfusion and coronary flow in infarct patients treated with fibrinolytic agents.

METHODS

Consecutive 78 patients with STEMI were randomized to receive clopidogrel plus aspirin (clopidogrel group, n = 42) or placebo plus aspirin (placebo group, n = 36) before streptokinase. Maximum and total ST-segment resolutions (sumSTR) were calculated at 90 minutes after fibrinolysis. TIMI flow grade and corrected TIMI frame count in infarct-related artery were evaluated at predischarge. Inhospital ischemic and hemorrhagic events were also analyzed.

RESULTS

Baseline characteristics were comparable in both groups. Both mean maximum ST-segment resolution (54.5 +/- 21.3% vs 44.6 +/- 22.0%, P = .047 ) and sumSTR (52.7 +/- 21.1% vs 42.8 +/- 20.7%, P = .041) were slightly higher in the clopidogrel group than placebo group. The rate of complete sumSTR 70% was significantly higher in the clopidogrel group compared with placebo group (31% vs 11%, P = .021). TIMI flows were similar in both groups, but corrected TIMI frame count was significantly lower in the clopidogrel group compared with placebo group (25.5 +/- 10.5 vs 33.5 +/- 11.8 frames, P = .027). Clinical events were comparable in 2 groups; however, there were 1 death caused by heart failure and moderate bleeding in the clopidogrel group.

CONCLUSION

Our results suggest that clopidogrel plus aspirin compared with aspirin alone may improve myocardial tissue perfusion and coronary flow in STEMI patients receiving streptokinase.

Role of Sam68 as an adaptor protein in signal transduction

Sam68, the substrate of Src in mitosis, belongs to the family of RNA binding proteins. Sam68 contains consensus sequences to interact with other proteins via specific domains. Thus, Sam68 has various proline-rich sequences to interact with SH3 domain-containing proteins. Moreover, Sam68 also has a C-terminal domain rich in tyrosine residues that is a substrate for tyrosine kinases. Tyrosine phosphorylation of Sam68 promotes its interaction with SH2 containing proteins. The association of Sam68 with SH3 domain-containing proteins, and its tyrosine phosphorylation may negatively regulate its RNA binding activity. The presence of these consensus sequences to interact with different domains allows this protein to participate in signal transduction pathways triggered by tyrosine kinases. Thus, Sam68 participates in the signaling of T cell receptors, leptin and insulin receptors. In these systems Sam68 is tyrosine phosphorylated and recruited to specific signaling complexes. The participation of Sam68 in signaling suggests that it may function as an adaptor molecule, working as a dock to recruit other signaling molecules. Finally, the connection between this role of Sam68 in protein-protein interaction with RNA binding activity may connect signal transduction of tyrosine kinases with the regulation of RNA metabolism.

Relation between electrocardiographic ST-segment resolution and early and late outcomes after primary percutaneous coronary intervention for acute myocardial infarction

ST-segment resolution (STR) is a surrogate end point in reperfusion trials of acute myocardial infarction, but there are few data regarding the optimum methods of measurement, clinical predictors, and correlation with late cardiac mortality. Consecutive patients (n = 1,005) who had acute myocardial infarction and >/=2 mm ST-segment elevation controlled with primary percutaneous coronary intervention (PCI) constituted our study group. Follow-up was obtained in 97% of patients at a median of 6.2 years. STR measured as maximum ST-segment elevation after PCI provided better discrimination of late cardiac mortality than did STR measured as percent resolution. Complete STR (<1.0 mm ST-segment elevation after PCI) was achieved in only 42% of patients. Anterior infarction, Killip's class 3 to 4, and Thrombolysis In Myocardial Infarction flow grades <2 before PCI and <3 after PCI were strong independent predictors of partial or poor STR. STR (complete [<1.0 mm] vs partial [1.0 to 2.0 mm] vs poor [>2.0 mm]) correlated with in-hospital mortality (4.0% vs 6.7% vs 11.6%, p = 0.005), reinfarction (1.4% vs 3.4% vs 6.1%, p = 0.01), and late cardiac mortality (17% vs 25% vs 44%, p <0.0001). Correlation with late mortality was stronger for nonanterior than for anterior infarction. Poor STR was a strong independent predictor of late mortality (hazard ratio 1.63, 95% confidence interval 1.06 to 2.50, p = 0.028), even after adjusting for Thrombolysis In Myocardial Infarction flow. These data support the use of STR as a simple method to stratify patients by risk after primary PCI for acute myocardial infarction and support the use of STR as a surrogate end point in reperfusion trials of acute myocardial infarction.

ST resolution in a single electrocardiographic lead: a simple and accurate predictor of cardiac mortality in patients with fibrinolytic therapy for acute ST-elevation myocardial infarction

BACKGROUND

The extent of ST-segment resolution in the 12-lead electrocardiograph (ECG) obtained early after reperfusion therapy in patients with ST-elevation myocardial infarction (MI) has been shown to predict short- and long-term mortalities. To improve the ease of this method in clinical practice, we sought to evaluate the optimal cutoffs and the prognostic value of ST resolution (STR) measured in a single ECG lead.

METHODS

In conjunction with the Intravenous nPA for the Treatment of Infarcting Myocardium Early (InTIME)-2 study, in which patients with an ST-elevation MI of <6 hours' duration were treated with alteplase or lanoteplase, 12-lead ECGs were obtained at baseline and 90 minutes after the start of fibrinolytic therapy in 3030 patients.

RESULTS

There was a close correlation between the extent of the sum STR and single-lead ST-elevation resolution ( r = 0.94). The optimal cutoffs for definition of single-lead complete, partial, and no-STR groups were 70% and 50% for anterior infarcts and 70% and 20% for inferior infarcts. The cardiac 30-day mortality rates for the 2 sets of risk groups by sum or single-lead STR were as follows: no resolution, 9.5% vs 10.3%; partial resolution, 5.0% vs 3.6%; complete resolution, 2.0% vs 1.2%. The predictive power was significantly better for single-lead STR.

CONCLUSIONS

ST resolution obtained in a single lead is an easy and accurate prognosticator of cardiac 30-day mortality in patients with ST-elevation MI. It is therefore useful for early identification of low- and high-risk subgroups after fibrinolysis and as a surrogate end point in clinical trials.

[Prediction of outcome in ST elevation myocardial infarction by the extent of ST segment deviation recovery. Which method is best?]

Simple and rapid measures are needed for timely assessment of the quality of reperfusion therapy early after fibrinolysis in acute STEMI. Sum ST segment elevation resolution (sum STR) categorized into the three groups of low risk (complete ST resolution), medium risk (partial ST resolution), and high risk (no ST resolution) has become an established method to predict infarct size, left ventricular function, epicardial vessel patency, and mortality. However, measurement of the sum of ST elevation from all leads of repeated ECG's is time-consuming. For routine practice more simple measures are needed. This report summarizes recent findings on direct comparisons between different modes of evaluation of ST segment deviation recovery employed for risk stratification in large-scale mortality trials. With respect to predictive accuracy combined with simplicity, two methods were superior to the conventional model of sum STR: 1) ST segment deviation resolution in only the one ECG lead showing the maximal deviation (single lead STR), and 2) the existing ST segment deviation in the single ECG lead of maximum deviation present 90 or 180 min after start of fibrinolysis (max STE). In multivariate analyses the ST segment deviation recovery models including sum STR were significant independent predictors of short- and long-term mortality. In receiver-operating characteristic (ROC) curves for predicting mortality the analysis of single lead STR and max STE performed better than sum STR. After categorization into risk groups patients are best classified by max STE. With an ECG recorded at 90 min in 2719 patients, the proportion of patients of sum STR, single lead STR, and max STE were 40, 34, and 43% in the low risk groups, and 24, 31, and 25% in the high risk groups. Cardiac mortality rates at 30 days were 2.0, 1.2, and 1.0% in low risk versus 9.6, 10.3, and 12.8% in the high risk groups, respectively. Long-term mortality with a followup of 5 years was best predicted by max STE risk groups.

CONCLUSION

Single lead STR and max STE are very simple, inexpensive, non-invasive, and highly reliable measures which provide very strong early prognostic information. The relationship between degree of ST segment deviation recovery and subsequent mortality is remarkably consistent. Both methods perform better than sum STR in predicting mortality. They can be used for very early risk stratification and can form a basis for an individual treatment of patients after fibrinolysis for STEMI within 6 hours of symptom onset. Of the two methods max STE is even simpler to use and has better accuracy in predicting outcome.

Impact of anemia in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention

OBJECTIVES

We sought to investigate the impact of anemia in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI).

BACKGROUND

The prognostic importance of anemia on primary PCI outcomes is unknown.

METHODS

In the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial, 2,082 patients of any age with AMI within 12 h onset undergoing primary PCI were randomized to balloon angioplasty versus stenting, each +/- abciximab. Outcomes were stratified by the presence of anemia at baseline, as defined by World Health Organization criteria (hematocrit <39% for men and <36% for women).

RESULTS

Anemia was present in 260 (12.8%) of 2,027 randomized patients with baseline laboratory values. Patients with versus without baseline anemia more frequently developed in-hospital hemorrhagic complications (6.2% vs. 2.4%, p = 0.002), had higher rates of blood product transfusions (13.1% vs. 3.1%, p < 0.0001), and had a prolonged (median 4.1 vs. 3.5 days, p < 0.0001) and more expensive (median costs $12,434 vs. $11,603, p = 0.002) index hospitalization. Patients with versus without anemia had strikingly higher mortality during hospitalization (4.6% vs. 1.1%, p = 0.0003), at 30 days (5.8% vs. 1.5%, p < 0.0001), and at 1 year (9.4% vs. 3.5%, p < 0.0001). The rates of disabling stroke at 30 days (0.8% vs. 0.1%, p = 0.005) and at 1 year (2.1% vs. 0.4%, p = 0.0007) were also significantly higher in patients with anemia. By multivariate analysis, anemia was an independent predictor of in-hospital mortality (hazard ratio, 3.26; p = 0.048) and one-year mortality (hazard ratio, 2.38; p = 0.016).

CONCLUSIONS

Anemia at baseline in patients with AMI undergoing primary PCI is common, and is strongly associated with adverse outcomes and increased mortality.

Antithrombotic Therapy for Acute Coronary Syndromes

OBJECTIVES

To review the role of antithrombotic therapy for treatment of acute coronary syndromes (ACS) in the hospital setting.

DATA SOURCES

Recent (1995-2003) published scientific literature, as identified by the authors through Medline searches, using the terms acute coronary syndromes, antithrombotic, antiplatelet, clinical trials, and reviews on treatment.

STUDY SELECTION

Recent systematic English-language review articles and reports of controlled randomized clinical trials were screened for inclusion.

DATA SYNTHESIS

For the patient with ST-segment elevation (STE) ACS, nonenteric-coated aspirin should be initiated immediately, if possible before arrival at the emergency department. In-hospital treatment is aimed at rapidly re-establishing coronary patency by means of percutaneous coronary intervention (PCI) or thrombolysis, preventing cardiac complications, and improving survival. Patients undergoing primary PCI should receive a glycoprotein IIb/IIIa receptor inhibitor, unfractionated heparin (UFH), and clopidogrel (Plavix--Bristol-Myers Squibb/Sanofi Pharmaceuticals Partnership) if bypass surgery is not urgently indicated; those undergoing thrombolysis should receive UFH. For the patient with non-ST-segment elevation (NSTE) ACS, beta-blockers, nitrates (also indicated for STE myocardial infarction), antiplatelet agents, and antithrombin therapy (UFH or low-molecular-weight heparin) are provided in standard care. Aspirin should be commenced immediately and continued indefinitely; in addition, clopidogrel is recommended for patients who are medically managed and those undergoing PCI. Glycoprotein IIb/IIIa receptor inhibitors (tirofiban [Aggrastat--Guilford Pharmaceuticals], eptifibatide [Integrilin--Millennium Pharmaceuticals], and abciximab [ReoPro--Lilly]) are of benefit in reducing ischemic complications in patients undergoing PCI.

CONCLUSION

Early reperfusion with thrombolytics or primary PCI is required in patients presenting with STE ACS. Early invasive management is recommended for high-risk patients with NSTE ACS; for lower-risk patients, either early invasive or early conservative therapy is recommended.