PubMed Health⌕ Search

Biomedical subjects

Deborah B Diercks

Publications and source records attributed to Deborah B Diercks.

At least 19 recordsLinked to original sources

Electrocardiogram differentiation of benign early repolarization versus acute myocardial infarction by emergency physicians and cardiologists.

OBJECTIVES: ST-segment elevation (STE) related to benign early repolarization (BER), a common normal variant, can be difficult to distinguish from acute myocardial infarction (AMI). The authors compared the electrocardiogram (ECG) interpretations of these two entities by emergency physicians (EPs) and cardiologists. METHODS: Twenty-five cases (13 BER, 12 AMI) of patients presenting to the emergency department with chest pain were identified. Criteria for BER required four of the following: 1) widespread STE (precordial greater than limb leads), 2) J-point elevation, 3) concavity of initial up-sloping portion of ST segment, 4) notching or irregular contour of J point, and 5) prominent, concordant T waves. Additional BER criteria were 1) stable ECG pattern, 2) negative cardiac injury markers, and 3) normal cardiac stress test or angiography. AMI criteria were 1) regional STE, 2) positive cardiac injury markers, and 3) identification of culprit coronary artery by angiography in less than eight hours of presentation. The 25 ECGs were distributed to 12 EPs and 12 cardiologists (four in academic medicine, four in community practice, and four in community academics [health maintenance organization] in each physician group). The physicians were informed of the patients' age, gender, and race, and they then interpreted the ECGs as BER or AMI. Undercalls (AMI misdiagnosed as BER) and overcalls (BER misdiagnosed as AMI) were calculated for each physician group. RESULTS: Cardiologists correctly interpreted 90% of ECGs, and EPs correctly interpreted 81% of ECGs. The proportion of undercalls (missed AMI/total AMI) was 2.8% for cardiologists (95% confidence interval [CI] = 0.09% to 5.5%) compared with 9.7% for EPs (95% CI = 4.8% to 14.6%) (p = 0.02). The proportion of overcalls (missed BER/total BER) was 17.3% for cardiologists (95% CI = 11.4% to 23.3%) versus 27.6% for EPs (95% CI = 20.6% to 34.6%) (p = 0.03). The mean number of years in practice was 19.8 for cardiologists (95% CI = 19 to 20.5) and 11 years for EPs (95% CI = 10.5 to 12.0) (p < 0.001). CONCLUSIONS: Although correct interpretation was high in both groups, cardiologists, who had significantly more years of practice, had fewer misinterpretations than EPs in distinguishing BER from AMI electrocardiographically.

Atrial Function↗

The obesity paradox in non-ST-segment elevation acute coronary syndromes: results from the Can Rapid risk stratification of Unstable angina patients Suppress ADverse outcomes with Early implementation of the American College of Cardiology/American Heart Association Guidelines Quality Improvement Initiative.

BACKGROUND: Although obesity is a known risk factor for coronary artery disease, its impact on the presentation, treatment, and outcome of patients with acute coronary syndromes (ACS) has not been well studied. METHODS: Using data from the CRUSADE Initiative, we compared inhospital treatments and clinical outcomes of 80845 patients with high-risk non-ST-segment elevation (NSTE) ACS (positive cardiac markers and/or ischemic ST-segment changes) to determine whether there was an association with body mass index (BMI [kg/m2]). Patient weights were categorized according to World Health Organization classifications: Underweight (BMI <18.5), Normal range (BMI 18.5-24.9), Overweight (BMI 25-29.9), Obese Class I (BMI 30-34.9), Obese Class II (BMI 35-39.9), and Extremely Obese (BMI =40). RESULTS: Most (70.5%) of the CRUSADE patients were classified as overweight or obese; these patients were younger and more likely to present with comorbid conditions, including diabetes mellitus, hypertension, and hyperlipidemia. Medications given during the first 24 hours and invasive cardiac procedures recommended by the American College of Cardiology/American Heart Association guidelines for NSTE ACS were more commonly used in these patients. The incidence of death and death and reinfarction, adjusted for covariates, were generally lower in overweight and obese patients, compared with normal-weight patients, but higher in underweight and extremely obese patients. CONCLUSIONS: Most patients with NSTE ACS are overweight or obese. These patients receive more aggressive treatment, and, except for the extremely obese, have less adverse outcomes compared with underweight and normal-weight patients. Although obesity appears to be a risk factor for developing ACS at a younger age, it also appears to be associated with more aggressive ACS management and, ultimately, improved outcomes.

Aged↗

The impact of emergency department structure and care processes in delivering care for non-ST-segment elevation acute coronary syndromes.

BACKGROUND: We sought to assess the influence of emergency department (ED) structure and care processes on adherence to practice guidelines for the treatment of patients with non-ST-segment elevation acute coronary syndromes. METHODS: We surveyed emergency physicians and nurses from 316 hospitals participating in the CRUSADE Quality Improvement Initiative and used multivariable modeling to correlate ED-specific characteristics with guidelines adherence. RESULTS: Factors that were significantly associated with improved guidelines adherence included collaboration between emergency physicians and hospital administration, northeast region, adequate nursing support, use of locum tenens physicians, an independent ED (not a division of another clinical department), and use of a care algorithm for acute coronary syndromes. CONCLUSIONS: Quality improvement strategies that have the full support of hospital administration, focus on increasing collaboration between emergency physicians and other health care providers, and specified protocol-driven management algorithm may be the most successful methods for improving the care and outcomes of patients with non-ST-segment elevation acute coronary syndromes.

Acute Disease↗

Door-to-ECG time in patients with chest pain presenting to the ED.

OBJECTIVE: To describe time to electrocardiogram (ECG) acquisition, identify factors associated with timely acquisition, and evaluate the influence of time to ECG on adverse clinical outcomes. METHODS: We measured the door-to-ECG time for emergency department patients enrolled in prospective chest pain registry. Clinical outcomes were defined as occurrence of myocardial infarction or death within 30 days of the visit. RESULTS: Among patients with acute coronary syndrome (ACS), 34% and 40.9% of patients with non-ST-elevation ACS and ST-elevation myocardial infarction (STEMI), respectively, had an ECG performed within 10 minutes of arrival. A delay in ECG acquisition was only associated with an increase risk of clinical outcomes in patients with STEMI at 30 days (odds ratio, 3.95; 95% confidence interval, 1.06-14.72; P = .04). CONCLUSION: Approximately one third of patients with ACS received an ECG within 10 minutes. A prolonged door-to-ECG time was associated with an increased risk of clinical outcomes only in patients with STEMI.

Adult↗

ED patients with heart failure: identification of an observational unit-appropriate cohort.

OBJECTIVE: To identify factors that define a low-risk cohort of patients with acute decompensated heart failure who are suitable for management in an observation unit. METHODS: Prospective convenience sample of 538 patients who presented to an ED with a diagnosis of congestive heart failure. Observation unit appropriate was defined as a length of stay less than 24 hours and no adverse events (myocardial infarction, death, arrhythmia, or rehospitalization) during the 30-day follow-up period. RESULTS: Study criteria were met by 499 patients (mean age, 61 +/- 15 years), and 234 (47%) were women. Of these, 133 (27%) met the criteria for observation unit appropriateness. Independent predictors were systolic blood pressure of greater than 160 (odds ratio, 1.8; 95% confidence interval, 1.15-2.7) and normal troponin I (odds ratio, 14.7; 95% confidence interval, 1.9-105). CONCLUSION: Initial blood pressure and troponin I can help identify patients with congestive heart failure at low risk for prolonged hospitalization and adverse events and who are reasonable candidates for observation unit management.

Aged↗

Frequency and consequences of recording an electrocardiogram >10 minutes after arrival in an emergency room in non-ST-segment elevation acute coronary syndromes (from the CRUSADE Initiative).

We sought to determine the frequency of electrocardiographic (ECG) acquisition within 10 minutes of hospital arrival, factors associated with delayed ECG acquisition, and any relation among delayed ECG acquisition, treatment patterns, and clinical outcomes. We therefore analyzed data from 63,478 patients (26,615 women, 42%) with high-risk non-ST-segment elevation acute coronary syndromes (designated by positive cardiac markers and/or ischemic ST-segment changes) who were enrolled in the CRUSADE Quality Improvement Initiative from February 2001 to March 2004. Patients were categorized based on time to electrocardiography as delayed (>10 minutes from hospital arrival) or nondelayed (<10 minutes). Multivariable predictors of delayed ECG acquisition were determined. Overall, median time to electrocardiography was 15 minutes (25th to 75th percentile 7 to 32). ECG acquisition was delayed (median 25 minutes, 25th to 75th percentile 16 to 50) in 41,397 patients (65.2%). In the remaining 34.8%, time to electrocardiography was <10 minutes (median 5 minutes, 25th to 75th percentile 3 to 8). Women were more likely than men to have delayed ECG acquisition (69% vs 62%), and female gender was the most significant predictor of delayed ECG acquisition (odds ratio 1.29, 95% confidence interval 1.25 to 1.34). In conclusion, only 33% of high-risk patients with non-ST-segment elevation acute coronary syndrome had an initial electrocardiogram obtained <10 minutes of arrival as recommended. Women were significantly more likely than men to have delayed ECG acquisition. Emergency departments should focus on decreasing the time to initial ECG acquisition to improve treatment of acute coronary syndrome in this group.

Aged↗

Pretest probability assessment derived from attribute matching.

BACKGROUND: Pretest probability (PTP) assessment plays a central role in diagnosis. This report compares a novel attribute-matching method to generate a PTP for acute coronary syndrome (ACS). We compare the new method with a validated logistic regression equation (LRE). METHODS: Eight clinical variables (attributes) were chosen by classification and regression tree analysis of a prospectively collected reference database of 14,796 emergency department (ED) patients evaluated for possible ACS. For attribute matching, a computer program identifies patients within the database who have the exact profile defined by clinician input of the eight attributes. The novel method was compared with the LRE for ability to produce PTP estimation <2% in a validation set of 8,120 patients evaluated for possible ACS and did not have ST segment elevation on ECG. 1,061 patients were excluded prior to validation analysis because of ST-segment elevation (713), missing data (77) or being lost to follow-up (271). RESULTS: In the validation set, attribute matching produced 267 unique PTP estimates [median PTP value 6%, 1st-3rd quartile 1-10%] compared with the LRE, which produced 96 unique PTP estimates [median 24%, 1st-3rd quartile 10-30%]. The areas under the receiver operating characteristic curves were 0.74 (95% CI 0.65 to 0.82) for the attribute matching curve and 0.68 (95% CI 0.62 to 0.77) for LRE. The attribute matching system categorized 1,670 (24%, 95% CI = 23-25%) patients as having a PTP < 2.0%; 28 developed ACS (1.7% 95% CI = 1.1-2.4%). The LRE categorized 244 (4%, 95% CI = 3-4%) with PTP < 2.0%; four developed ACS (1.6%, 95% CI = 0.4-4.1%). CONCLUSION: Attribute matching estimated a very low PTP for ACS in a significantly larger proportion of ED patients compared with a validated LRE.

Acute Disease↗

Gender disparities in the diagnosis and treatment of non-ST-segment elevation acute coronary syndromes: large-scale observations from the CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes With Early Implementation of the American College of Cardiology/American Heart Association Guidelines) National Quality Improvement Initiative.

OBJECTIVES: We hypothesized that significant disparities in gender exist in the management of patients with non-ST-segment elevation (NSTE) acute coronary syndromes (ACS). BACKGROUND: Gender-related differences in the diagnosis and treatment of ACS have important healthcare implications. No large-scale examination of these disparities has been completed since the publication of the revised American College of Cardiology/American Heart Association guidelines for management of patients with NSTE ACS. METHODS: Using data from the CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of the American College of Cardiology/American Heart Association Guidelines) National Quality Improvement Initiative, we examined differences of gender in treatment and outcomes among patients with NSTE ACS. RESULTS: Women (41% of 35,875 patients) were older (median age 73 vs. 65 years) and more often had diabetes and hypertension. Women were less likely to receive acute heparin, angiotensin-converting enzyme inhibitors, and glycoprotein IIb/IIIa inhibitors and less commonly received aspirin, angiotensin-converting enzyme inhibitors, and statins at discharge. The use of cardiac catheterization and revascularization was higher in men, but among patients with significant coronary disease, percutaneous revascularization was performed in a similar proportion of women and men. Women were at higher risk for unadjusted in-hospital death (5.6% vs. 4.3%), reinfarction (4.0% vs. 3.5%), heart failure (12.1% vs. 8.8%), stroke (1.1% vs. 0.8%), and red blood cell transfusion (17.2% vs. 13.2%), but after adjustment, only transfusion was higher in women. CONCLUSIONS: Despite presenting with higher risk characteristics and having higher in-hospital risk, women with NSTE ACS are treated less aggressively than men.

Acute Disease↗

2004 American College of Cardiology/American Heart Association guidelines for the management of patients with ST-elevation myocardial infarction: implications for emergency department practice.

The American College of Cardiology and the American Heart Association last published evidence-based guidelines for the management of ST-segment elevation myocardial infarction (STEMI) in 1999. In mid-2004, in recognition of the evolution and improvement of many of the most basic tenets of clinical management of STEMI since that time, an updated edition of the STEMI guidelines has been published. These guidelines offer many evidence-based recommendations that are pertinent to the out-of-hospital and emergency department care of STEMI patients, including initial evaluation, risk stratification, stabilizing management, and the choice between pharmacologic and mechanical revascularization. These are presented and discussed here.

Electrocardiography↗

Changes in the numeric descriptive scale for pain after sublingual nitroglycerin do not predict cardiac etiology of chest pain.

STUDY OBJECTIVE: We determine whether the change in numeric descriptive scale for pain after sublingual nitroglycerin use can predict cardiac etiology of chest pain. METHODS: A prospective study of a convenience sample of patients who had chest pain, presented to the emergency department from May 24, 2001, to April 30, 2002, and received sublingual nitroglycerin during their evaluation was performed. The 11-point numeric descriptive scale for chest pain was recorded before and after the initial dose of sublingual nitroglycerin. Cardiac-related pain was defined as chest pain in a patient with a discharge diagnosis of myocardial infarction or the diagnosis of coronary artery disease based on a positive diagnostic study (cardiac catheterization or noninvasive stress imaging). Change in the numeric descriptive scale was divided into 4 categories: (1) significant/complete reduction; (2) moderate reduction; (3) minimal reduction; and (4) no change. RESULTS: The study cohort was composed of 664 patients: 345 women (52%) and 319 men (48%), mean age 52 years (+/-12.4 years). Cardiac-related chest pain was identified in 122 patients (18%). In the overall patient population, 125 (19%) patients had no change in pain, 206 (31%) patients had minimal reduction, 145 (22%) patients had moderate reduction, and 188 (28%) patients had significant or complete reduction in pain. There was no significant difference in any subgroup of numeric descriptive scale response to sublingual nitroglycerin administration in patients with and without a diagnosis of cardiac chest pain. CONCLUSION: In this convenience sample, the response of chest pain to sublingual nitroglycerin was not a reliable indicator of a cardiac etiology.

Administration, Sublingual↗

Chest pain units: management of special populations.

Chest pain units provide an important alternative to traditional hospital admission for patients who present to the emergency department with symptoms compatible with acute coronary syndrome and a normal or inconclusive initial evaluation. Although patient subgroups such as women, diabetics, those with established coronary artery disease,and those with symptoms related to stimulant use present unique challenges,management in a chest pain unit appears to be appropriate in these populations. Judicious application of accelerated diagnostic protocols and current testing methods can promote safe, accurate, and cost-effective risk stratification of special populations to identify patients who can be safely discharged and patients who require hospital admission for further evaluation.

Angina Pectoris↗

Exercise testing in chest pain units: rationale, implementation, and results.

Chest pain units are now established centers for assessment of low-risk patients presenting to the emergency department with symptoms suggestive of acute coronary syndrome. Accelerated diagnostic protocols, of which treadmill testing is a key component, have been developed within these units for efficient evaluation of these patients. Studies of the last decade have established the utility of early exercise testing,which has been safe, accurate, and cost-effective in this setting. Specific diagnostic protocols vary, but most require 6 to 12 hours of observation by serial electrocardiography and cardiac injury markers to exclude infarction and high-risk unstable angina before proceeding to exercise testing. However, in the chest pain unit at UC Davis Medical Center,the approach includes "immediate" treadmill testing without a traditional process to rule out myocardial infarction. Extensive experience has validated this approach in a large, heterogeneous population. The optimal strategy for evaluating low-risk patients presenting to the emergency department with chest pain will continue to evolve based on current research and the development of new methods.

Acute Disease↗

Right precordial and posterior electrocardiographic leads do not increase detection of ischemia in low-risk patients presenting with chest pain.

BACKGROUND: A number of innovative approaches have been investigated for their value in the early detection of acute ischemia or infarction in patients presenting to the emergency department (ED) with chest pain suggestive of a cardiac origin. Prior investigations have demonstrated the utility of adding right precordial and posterior chest leads to the standard 12-lead electrocardiogram (ECG) for identifying right ventricular and posterior wall infarctions in the ED. HYPOTHESIS: To assess the utility of additional ECG leads in low-risk patients presenting to the ED with symptoms suggestive of acute coronary syndromes who are managed in a chest pain evaluation unit (CPEU). METHODS: We studied low-risk patients who presented to the ED with chest pain compatible with myocardial ischemia. Low-risk patients were identified by a normal 12-lead ECG, no arrhythmias or hemodynamic instability, and one negative serum cardiac troponin I. Patients were admitted to the CPEU where a 16-lead ECG was recorded by the addition of 2 right-sided precordial leads (V4R, V5R) and 2 posterior leads (V8, V9) to the standard 12-lead ECG. RESULTS: The 16-lead ECG system was applied to 316 consecutive patients. The study group was a middle-aged population with equal numbers of men and women and an average of 2 cardiac risk factors per patient. The 16-lead ECG demonstrated evidence of myocardial injury in only 1 patient and no evidence of ischemia in any of the 316 patients. CONCLUSION: In patients presenting to the ED with chest pain and evidence of low clinical risk by our criteria, the addition of both right-sided precordial and posterior chest leads to the standard 12-lead ECG did not provide additional information for risk stratification.

Aged↗

Electrocardiographic manifestations: electrolyte abnormalities.

Because myocyte depolarization and repolarization depend on intra- and extracellular shifts in ion gradients, abnormal serum electrolyte levels can have profound effects on cardiac conduction and the electrocardiogram (EKG). Changes in extracellular potassium, calcium, and magnesium levels can change myocyte membrane potential gradients and alter the cardiac action potential. These changes can result in incidental findings on the 12-lead EKG or precipitate potentially life-threatening dysrhythmias. We will review the major electrocardiographic findings associated with abnormalities of the major cationic contributors to cardiac conduction-potassium, calcium and magnesium.

Adult↗

Insurance status and the treatment of myocardial infarction at academic centers.

UNLABELLED: Numerous studies have documented treatment disparities in patients with acute coronary syndromes based on race and gender. Other causes for treatment disparities may exist. OBJECTIVES: To determine if insurance status affects quality of care in patients with acute myocardial infarction (AMI) presenting to academic health centers. METHODS: The Internet Tracking Registry for Acute Coronary Syndromes (i*trACS), a prospective multicenter registry of patients with chest pain presenting to the emergency department who receive an electrocardiogram, was used as the database (N = 17,737). A subset of patients who were diagnosed as having AMI were selected from the database (n = 936). Patients were classified as having either ST-segment elevation MI (n = 178) or non-ST-segment elevation MI (n = 758). Insurance status, age, race, and gender were extracted as predictor variables. The influence of predictor variables on treatment modality was investigated using logistic regression, adjusted for clustering within sites. RESULTS: The odds of a self-pay patient with ST-segment elevation MI receiving fibrinolytics were 3.23 (95% CI = 1.56 to 6.69) times higher than for other patients. Patients with Medicare coverage were less likely to receive fibrinolytics (odds ratio [OR] 0.35, 95% CI = 0.19 to 0.65) and tended to undergo percutaneous coronary intervention less often (OR 0.60, 95% CI = 0.36 to 1.01). The odds of a privately insured patient's receiving coronary artery bypass grafting (OR 2.76, 95% CI = 1.62 to 4.72) or percutaneous coronary intervention (OR 1.47, 95% CI = 1.03 to 2.11) were higher than for other patients. CONCLUSIONS: Insurance coverage appears to affect treatment in patients with AMI, with self-pay patients more likely to receive less-expensive therapies and insured patients more likely to receive invasive treatments.

Academic Medical Centers↗