Charlotte S Roberts

Comprehensive Strategy for the Evaluation and Triage of the Chest Pain Patient

STUDY OBJECTIVE To evaluate the safety and efficacy of a systematic evaluation and triage strategy including immediate resting myocardial perfusion imaging in patients presenting to the emergency department with chest pain of possible ischemic origin. METHODS We conducted an observational study of 1,187 consecutive patients seen in the ED of an urban tertiary care hospital with the chief complaint of chest pain. Within 60 minutes of presentation, each patient was assigned to one of five levels on the basis of his or her risk of myocardial infarction (MI) or unstable angina (UA): level 1, MI; level 2, MI/UA; level 3, probable UA; level 4, possible UA; and level 5, noncardiac chest pain. In the lower risk levels (3 and 4), immediate resting myocardial perfusion imaging was used as a risk-stratification tool alone (level 4) or in combination with serial markers (level 3). RESULTS Acute MI, early revascularization indicative of acute coronary syndrome, or both were consistent with risk designations: level 1: 96% MI, 56% revascularization; level 2: 13% MI, 29% revascularization; level 3: 3% MI, 17% revascularization; level 4: .7% MI; 2.5% revascularization. Sensitivity of immediate resting myocardial perfusion imaging for MI was 100% (95% confidence interval [CI], 64% to 100%) and specificity 78% (74% to 82%). In patients with abnormal imaging findings, risk for MI (7% versus 0%, P < .001; relative risk [RR], 50; 95% CI, 2.8 to 889) and for MI or revascularization (32% vs 2%, P < .001; RR, 15.5; 95% CI, 6.4 to 36) were significantly higher than in patients with normal imaging findings. During 1-year follow-up, patients with normal imaging findings (n = 338) had an event rate of 3% (revascularization) with no MI or death (combined events: negative predictive value, 97%; 95% CI, 95% to 98%). Patients with abnormal imaging findings (n = 100) had a 42% event rate (combined events: RR, 14.2; 95% CI, 6.5 to 30; P < .001), with 11% experiencing MI and 8% cardiac death. CONCLUSION This strategy is a safe, effective method for rapid triage of chest pain patients. Rapid perfusion imaging plays a key role in the risk stratification of low-risk patients, allowing discrimination of unsuspected high risk patients who require prompt admission and possible intervention from those who are truly at low risk.

Interleukin-1 Blockade With Anakinra to Prevent Adverse Cardiac Remodeling After Acute Myocardial Infarction (Virginia Commonwealth University Anakinra Remodeling Trial [VCU-ART] Pilot Study)

Acute myocardial infarction (AMI) initiates an intense inflammatory response in which interleukin-1 (IL-1) plays a central role. The IL-1 receptor antagonist is a naturally occurring antagonist, and anakinra is the recombinant form used to treat inflammatory diseases. The aim of the present pilot study was to test the safety and effects of IL-1 blockade with anakinra on left ventricular (LV) remodeling after AMI. Ten patients with ST-segment elevation AMI were randomized to either anakinra 100 mg/day subcutaneously for 14 days or placebo in a double-blind fashion. Two cardiac magnetic resonance (CMR) imaging and echocardiographic studies were performed during a 10- to 14-week period. The primary end point was the difference in the interval change in the LV end-systolic volume index (LVESVi) between the 2 groups on CMR imaging. The secondary end points included differences in the interval changes in the LV end-diastolic volume index, and C-reactive protein levels. A +2.0 ml/m(2) median increase (interquartile range +1.0, +11.5) in the LVESVi on CMR imaging was seen in the placebo group and a -3.2 ml/m(2) median decrease (interquartile range -4.5, -1.6) was seen in the anakinra group (p = 0.033). The median difference was 5.2 ml/m(2). On echocardiography, the median difference in the LVESVi change was 13.4 ml/m(2) (p = 0.006). Similar differences were observed in the LV end-diastolic volume index on CMR imaging (7.6 ml/m(2), p = 0.033) and echocardiography (9.4 ml/m(2), p = 0.008). The change in C-reactive protein levels between admission and 72 hours after admission correlated with the change in the LVESVi (R = +0.71, p = 0.022). In conclusion, in the present pilot study of patients with ST-segment elevation AMI, IL-1 blockade with anakinra was safe and favorably affected by LV remodeling. If confirmed in larger trials, IL-1 blockade might represent a novel therapeutic strategy to prevent heart failure after AMI.

Comparative safety of interleukin-1 blockade with anakinra in patients with ST-segment elevation acute myocardial infarction (from the VCU-ART and VCU-ART2 pilot studies).

Two pilot studies of interleukin-1 (IL-1) blockade in ST-segment elevation myocardial infarction (STEMI) showed blunted acute inflammatory response and overall favorable outcomes at 3 months follow-up. We hereby present a patient-level pooled analysis with extended follow-up of 40 patients with clinically stable STEMI randomized to anakinra, a recombinant IL-1 receptor antagonist, 100 mg/day for 14 days or placebo in a double-blinded fashion. End points included death, cardiac death, recurrent acute myocardial infarction (AMI), stroke, unstable angina, and symptomatic heart failure. Median follow-up was 28 (interquartile range 3 to 38) months. Sixteen patients (40%) had a total of 22 adverse cardiovascular events: 1 cardiac death, 4 recurrent AMI, 5 episodes of unstable angina pectoris requiring hospitalization and/or urgent revascularization, and 11 new diagnoses of heart failure. Treatment with anakinra was associated with a hazard ratio of 1.08 (95% confidence interval 0.31 to 3.74, p = 0.90) for the combined end point of death, recurrent AMI, unstable angina pectoris, or stroke and a hazard ratio of 0.16 (95% confidence interval 0.03 to 0.76, p = 0.008) for death or heart failure. In conclusion, IL-1 blockade with anakinra for 2 weeks appears, therefore, to have a neutral effect on recurrent ischemic events, whereas it may prevent new-onset heart failure long term after STEMI.

An evaluation of the accuracy of emergency physician activation of the cardiac catheterization laboratory for patients with suspected ST-segment elevation myocardial infarction.

STUDY OBJECTIVE Current recommendations indicate that emergency physicians should activate cardiac catheterization laboratory personnel by a single page for ST-segment elevation myocardial infarction (STEMI) patients. We assessed the accuracy of emergency physician cardiac catheterization laboratory activations, angiographic findings, outcomes, and treatment times among patients with and without STEMI. METHODS We classified the appropriateness and outcomes of consecutive emergency physician STEMI pages between June 2006 and September 2008. Emergency physician activations of the cardiac catheterization laboratory were classified according to the findings of the initial ECG compared with cardiology interpretation for the presence of STEMI and presence of coronary disease. RESULTS During a 27-month period, emergency physician activation of the cardiac catheterization laboratory occurred 249 times. There were 188 (76%) patients with a true STEMI, of whom 13 did not receive emergency angiography. Of the 37 (15%) patients who had ECG findings meeting STEMI criteria and who ultimately did not have myocardial necrosis and underwent emergency angiography, 12 had significant disease and 5 had revascularization performed. Eleven patients had ECGs concerning for but not meeting STEMI criteria; all had emergency angiography (n=11) or received a diagnosis of non-STEMI (n=6). Only 13 patients were considered as having received unnecessary cardiac catheterization laboratory activations (5.2%) in which emergency angiography was not performed and myocardial infarction was excluded. CONCLUSION A significant number of emergency physician STEMI cardiac catheterization laboratory activations are for patients who did not meet standard STEMI criteria. However, most had ECG findings and symptoms that lead to emergency angiography, had significant disease, or were diagnosed with non-STEMI. Only a small percentage of patients received unnecessary cardiac catheterization laboratory activations. Our findings support current recommendations for emergency physician cardiac catheterization laboratory activation for potential STEMI patients.

Outcomes in patients with chronicity of left bundle- branch block with possible acute myocardial infarction

INTRODUCTION Guidelines derived from patients in clinical trials indicate that emergency department patients with likely myocardial infarction (MI) who have new left bundle-branch block (LBBB) should undergo rapid reperfusion therapy. Whether this pertains to lower risk emergency department patients with LBBB is unclear. METHODS A total of 401 consecutive patients with LBBB undergoing an MI rule-out protocol were included. Left bundle-branch blocks were classified as chronic; new; or, if no prior electrocardiogram (ECG) was available, as presumably new. Left bundle-branch blocks were considered concordant if there was ≥1 mm concordant ST elevation or depression. Rates of MI, peak MB values in MI patients, and 30-day mortality were compared across groups. RESULTS A majority of patients (64%) had new (37%) or presumably new LBBB (27%). A total of 116 patients (29%) had MI, with no significant difference in prevalence or size of MI among the 3 ECG groups. Myocardial infarction was diagnosed in 86% of patients with concordant ECG changes versus 27% of patients without concordant ECG changes (P < .01). Peak MB was >5× normal in 50% who had concordant ST changes compared to none of those who did not. Concordant ST changes were the most important predictor of MI (odds ratio 17, 95% CI 3.4-81, P < .001) and an independent predictor of mortality (odds ratio 4.3, 95% CI 1.3-15, P < .001); new or presumably new LBBB was neither. CONCLUSIONS Most patients with possible MI with new or presumably new LBBB do not have MI. Concordant ECG changes were an important predictor of MI and death. Current guidelines regarding early reperfusion therapy for patients with LBBB should be reconsidered.

Emergency physician-initiated cath lab activation reduces door to balloon times in ST-segment elevation myocardial infarction patients

OBJECTIVES We evaluated the impact of emergency physician (EP)-initiated primary percutaneous coronary intervention (PCI) via a single-group page on door to balloon (D2B) interval times in patients with ST-segment elevation myocardial infarction. METHODS Consecutive ST-segment elevation myocardial infarction patients presenting to the emergency department between February 2004 and September 2008 were divided into 4 groups: group 1, PCI performed on an ad hoc basis after cardiology consultation; group 2, primary PCI activated via a single-group page only on-call cardiology consultation; group 3, primary PCI with EP cardiac catheterization laboratory (CCL) activation via the same page strategy; group 4, prehospital CCL activation based on prehospital diagnostic electrocardiogram. Composite D2B and relevant time intervals were measured for each time group. RESULTS A total of 295 consecutive patients undergoing emergent angiography were included. Times decreased for most time intervals from groups 1 to 4. Although there was no significant change in composite D2B or any measured interval time with the introduction of PCI after emergent cardiology consultation, each decreased significantly after implementing an EP-initiated PCI strategy except CCL2B (D2B 95 to 77 minutes, D2E 14 to 10 minutes, D2CCL 71 to 50 minutes). Further significant reductions in D2B time were achieved among all patients after the institution of emergency medicine services activation of the CCL (D2B 77 to 64 minutes, D2CCL 50 to 38 minutes, CCL2B 28 to 22 minutes). CONCLUSIONS A systematic process of initiating D2B recommendations, including EP-initiated CCL activation via a single-group page, significantly reduces D2CCL and D2B times.

Mortality based on the presenting electrocardiogram in patients with myocardial infarction in the troponin era

BACKGROUND Studies reporting short-term mortality in patients with myocardial infarction (MI) based on the initial electrocardiogram (ECG) are often limited by requiring an ischemic ECG for inclusion. Because few patients with normal or nonspecific findings were included, outcomes in these patients are less clear, especially in the troponin era. METHODS Consecutive patients diagnosed as having MI using troponin I (TnI) over a 6-year period were included and classified into 8 mutually exclusive groups based on the initial ECG using standard criteria. Patients were included in only 1 group. The MI size was estimated using multiples of peak creatine kinase-MB (CK-MB), and 30-day mortality rate was assessed. RESULTS Among 1641 patients with MI, patients with ST elevation represented only 22% of all MIs. Patients with ST elevation had the largest MI size, with 2 of 3 having a peak CK-MB greater than 10 times normal. In contrast, most of the patients representing all the other ECG groups had a peak CK-MB less than 5 times normal, with approximately 1 of 3 having no CK-MB elevation and were diagnosed by TnI elevation alone. Patients could be separated into a high-risk group (ST elevation, ischemia, other, or left bundle-branch block), in which mortality rate exceeded 9% (mean, 14%), and a lower-risk group (prior MI, left ventricular hypertrophy, nonspecific changes, and normal), in which the 30-day mortality rate averaged 6% (P < .001; range, 5.23%-7.1%). CONCLUSIONS Specific ECG findings other than ischemia portend poor outcomes in patients with MI. Once MI is diagnosed, patients are no longer low risk.

Life-saving systemic thrombolysis in a patient with massive pulmonary embolism and a recent hemorrhagic cerebrovascular accident.

Massive pulmonary embolism is associated with mortality rates exceeding 50%. Current practice guidelines include the immediate administration of thrombolytic therapy in the absence of contraindications. However, thrombolysis for pulmonary embolism is said to be absolutely contraindicated in the presence of recent hemorrhagic stroke and other conditions. The current contraindications to thrombolytic therapy have been extrapolated from data on acute coronary syndrome and are not specific for venous thromboembolic disease. Some investigators have proposed that the current contraindications be viewed as relative, rather than absolute, in cases of high-risk pulmonary embolism. We present the case of a 60-year-old woman in whom massive pulmonary embolism led to cardiac arrest with pulseless electrical activity. Eight weeks earlier, she had sustained a hemorrhagic cerebrovascular accident-a classic absolute contraindication to thrombolytic therapy. Despite this practice guideline, we administered tissue plasminogen activator systemically in order to save the patients life. This therapy did not evoke intracranial bleeding, and the patient was eventually discharged from the hospital. Until guidelines specific to venous thromboembolic disease are developed, we think that the current contraindications to thrombolysis should be considered on an individual basis in patients who are at high risk of death from massive pulmonary embolism.

Implication of the New Low-Density Lipoprotein Goals in Dyslipidemia Management of Patients With Acute Coronary Syndrome

OBJECTIVE To assess the ability of patients with an acute coronary syndrome (ACS) to meet the recommended low-density lipoprotein cholesterol (LDL-C) goal of 100 mg/dL and optional aggressive lowering to 70 mg/dL. PATIENTS AND METHODS Patients diagnosed as having ACS who had lipid levels measured within 24 hours of admission from January 1, 1998, through December 31, 2002, were assessed for the ability to meet the 2 target LDL-C levels. Patients were considered to have ACS if they were diagnosed as having myocardial infarction, had significant disease on angiography, or had a history of coronary artery disease. Patients were classified into 1 of 4 groups on the basis of the degree of LDL-C lowering required to meet the 2 different goals: less than 33%, 33% to 39%, 40% to 49%, and 50% or more. Patients with myocardial infarction who had lipid sampling performed more than 24 hours after admission were excluded. RESULTS The mean plus-or-minus SD LDL-C level was 111 plus-or-minus 43 mg/dL in the 1322 patients who met criteria for ACS and had LDL-C levels assessed. On the basis of a target LDL-C value of less than 100 mg/dL, 43% of patients were at goal and did not require treatment, and only 2.5% had an LDL-C level that required a 50% or greater reduction to meet goal. In contrast, using the newer LDL-C target of 70 mg/dL, 85% patients required treatment, and 23% of patients required a 50% or greater decrease in LDL-C level and therefore were likely to require more than 1 lipid-lowering agent. CONCLUSION Decreasing the LDL-C target to less than 70 mg/dL substantially increases the number of patients with ACS who would require treatment. A significant proportion of patients will require a reduction in LDL-C level of 50% or more, which is not easily achievable with current lipid-lowering monotherapy.

An unusual presentation of chest pain: needle perforation of the right ventricle.

Foreign bodies in the heart are a rare occurrence and can result from intravenous drug abuse, trauma or iatrogenic causes. There are no current guidelines for the treatment of a cardiac foreign body. We hereby present a brief review of the available literature and report a case of a woman with chest pain subsequently complicated by cardiogenic shock due to tamponade secondary to a needle fragment perforating her right ventricular free wall.