Feasibility of combining serial smartphone single-lead electrocardiograms for the diagnosis of ST-elevation myocardial infarction.

BACKGROUND: The rate-limiting step in STEMI diagnosis often is the availability of a 12-lead electrocardiogram (ECG) and its interpretation. The potential may exist to speed the availability of 12-lead ECG information by using commonly available mobile technologies. We sought to test whether combining serial smartphone single-lead ECGs to create a virtual 12-lead ECG can accurately diagnose STEMI. METHODS: Consenting patients presenting with symptoms consistent with a possible STEMI had contemporaneous standard 12-lead and smartphone '12-lead equivalent' ECG (produced by electronically combining serial single-lead ECGs) recordings obtained. Matched ECGs were evaluated qualitatively and quantitatively by a panel of blinded readers and classified as STEMI/STEMI equivalent (LBBB), Not-STEMI, or uninterpretable. Interpretable ECG pairs were graded as showing good, fair, or poor correlation. RESULTS: Two hundred four subjects (age = 60 years, males = 57%, STEMI activation = 45%) were enrolled from 5 international sites. Smartphone ECG quality was graded as good in 151 (74.0%), fair in 32 (15.7%), poor in 8 (3.9%), and uninterpretable in 13 (6.4%). A STEMI/STEMI equivalent diagnosis was identified by standard 12-lead ECG in 57/204 (27.9%) recordings. For all interpretable pairs of smartphone ECGs compared with standard ECGs (n = 190), the sensitivity, specificity, and positive and negative predictive values for STEMI/STEMI equivalent by smartphone were 0.89, 0.84, 0.70 and 0.95, respectively. CONCLUSIONS: A '12-lead equivalent' ECG obtained from multiple serial single-lead ECGs from a smartphone can identify STEMI with good correlation to a standard 12-lead ECG. This technology holds promise to improve outcomes in STEMI by enhancing the reach and speed of diagnosis and thereby early treatment.

Smartphone ECG for evaluation of ST-segment elevation myocardial infarction (STEMI): Design of the ST LEUIS International Multicenter Study.

In patients experiencing an ST-elevation myocardial infarction (STEMI), rapid diagnosis and immediate access to reperfusion therapy leads to optimal clinical outcomes. The rate-limiting step in STEMI diagnosis is the availability and performance of a 12-lead ECG. Recent technology has provided access to a reliable means of obtaining an ECG reading through a smartphone application (app) that works with an attachment providing all 12-leads of a standard ECG system. The ST LEUIS study was designed to validate the smartphone ECG app and its ability to accurately assess the presence or absence of STEMI in patients presenting with chest pain compared with the gold standard 12-lead ECG. We aimed to support the diagnostic utility of smartphone technology to provide a timely diagnosis and treatment of STEMI. The study will take place over 12months at five institutions. Approximately 60 patients will be enrolled per institution, for a total recruitment of 300 patients.

Smartphone ECG for evaluation of STEMI: results of the ST LEUIS Pilot Study.

BACKGROUND: 12-lead ECG is a critical component of initial evaluation of cardiac ischemia, but has traditionally been limited to large, dedicated equipment in medical care environments. Smartphones provide a potential alternative platform for the extension of ECG to new care settings and to improve timeliness of care. OBJECTIVE: To gain experience with smartphone electrocardiography prior to designing a larger multicenter study evaluating standard 12-lead ECG compared to smartphone ECG. METHODS: 6 patients for whom the hospital STEMI protocol was activated were evaluated with traditional 12-lead ECG followed immediately by a smartphone ECG using right (VnR) and left (VnL) limb leads for precordial grounding. The AliveCor™ Heart Monitor was utilized for this study. All tracings were taken prior to catheterization or immediately after revascularization while still in the catheterization laboratory. RESULTS: The smartphone ECG had excellent correlation with the gold standard 12-lead ECG in all patients. Four out of six tracings were judged to meet STEMI criteria on both modalities as determined by three experienced cardiologists, and in the remaining two, consensus indicated a non-STEMI ECG diagnosis. No significant difference was noted between VnR and VnL. CONCLUSIONS: Smartphone based electrocardiography is a promising, developing technology intended to increase availability and speed of electrocardiographic evaluation. This study confirmed the potential of a smartphone ECG for evaluation of acute ischemia and the feasibility of studying this technology further to define the diagnostic accuracy, limitations and appropriate use of this new technology.

Identifying Barriers and Practical Solutions to Conducting Site-Based Research in North America: Exploring Acute Heart Failure Trials As a Case Study.

Although the prognosis of ambulatory heart failure (HF) has improved dramatically there have been few advances in the management of acute HF (AHF). Despite regional differences in patient characteristics, background therapy, and event rates, AHF clinical trial enrollment has transitioned from North America and Western Europe to Eastern Europe, South America, and Asia-Pacific where regulatory burden and cost of conducting research may be less prohibitive. It is unclear if the results of clinical trials conducted outside of North America are generalizable to US patient populations. This article uses AHF as a paradigm and identifies barriers and practical solutions to successfully conducting site-based research in North America.

Cardiac injury due to accidental discharge of nail gun.

BACKGROUND: Since 1991, the incidence of injuries associated with pneumatic and explosive powered nail guns has steadily been rising due to increasing use of these devices by the untrained consumer. The vast majority of injuries involve the extremities, but injuries have been reported to occur in virtually every area of the body. OBJECTIVE: Discuss the epidemiology, pathophysiology, and management of penetrating cardiac nail gun injuries. CASE REPORT: A 33-year-old man sustained a penetrating cardiac injury from accidental discharge of a nail gun. The patient had successful repair of a laceration to his right ventricle. CONCLUSIONS: Penetrating cardiac injuries from pneumatic nail guns are rare and have mortality similar to stab wounds. Improved safety mechanisms and training are the keys to prevention. Consideration also should be given to implementing legislation restricting the sale of nail guns.

Use of pulse co-oximetry as a screening and monitoring tool in mass carbon monoxide poisoning.

Carbon monoxide (CO) poisoning remains a common cause of poisoning in the United States. We describe a case where responding fire department personnel encountered a sick employee with a headache at an automotive brake manufacturing plant. Using both atmospheric CO monitoring and pulse CO-oximetry technology, fire department personnel were able to diagnose the cause of the patient's illness and later identify the source of CO in the plant.

The Effect of Emergency Medicine Residents on Clinical Efficiency and Staffing Requirements.

OBJECTIVES: The effect of emergency medicine (EM) residents on the clinical efficiency of attending physicians is controversial. The authors hypothesized that implementing a new EM residency program would result in an increase in relative value units (RVUs) generated per hour by attending physicians and decrease staffing requirements. METHODS: This was a retrospective observational analysis of an emergency department before, during, and after the establishment of a new EM residency program. We analyzed the change in RVUs billed, patients seen, and hours worked by attending physicians, midlevel providers (MLPs), and residents, and addressed potential confounding factors. RESULTS: The clinical efficiency of attending physicians increased by 70%, or 4.98 RVUs/hour (from 7.12 [SD ± 1.4] RVUs/hour to 12.1 [SD ± 2.2] RVUs/hour, p < 0.001) with the implementation of an EM residency program. Overall, net department RVU generation rose by 32%, even as attending physician coverage decreased by 6.3% (p < 0.05), and MLP coverage dropped by 60% (p < 0.05). We estimated that the implementation of the residency saved 4,860 hours of attending physician coverage and 5,828 hours of MLP coverage per year. This represents an estimated $1,741,265 in annual staffing savings, comparable to the residency program's annual operating cost of $1,821,108. CONCLUSIONS: The implementation of an EM residency program had a positive effect on the clinical efficiency of attending physicians and decreased staffing requirements.

Changes in Medical Therapy and Lifestyle After Anatomical or Functional Testing for Coronary Artery Disease.

BACKGROUND: Diagnostic testing in the care of patients newly presenting with symptoms suggestive of coronary artery disease may influence risk factor management, independent of test type or test results. However, little is known about changes in medications and lifestyle after anatomical or functional testing. METHODS AND RESULTS: We examined what factors influenced preventive medical therapy and lifestyle practices at 60 days among 10 003 symptomatic patients (53% women; mean age 61 years) randomly assigned to anatomical testing with coronary computed tomographic angiography or functional testing (NCT01174550). We also assessed the association of preventive changes with major cardiovascular events. There were no differences in medications/lifestyle at baseline. At 60 days, relative to baseline, the computed tomographic angiography strategy was associated with a higher proportion of patients newly initiating aspirin (11.8% versus 7.8%), statins (12.7% versus 6.2%), and ß-blockers (8.1% versus 5.3%), compared to functional testing (P<0.0001 for each). No significant differences between computed tomographic angiography and functional testing strategies were observed for initiation of exercise, quitting smoking, or weight loss in overweight/obese patients, though overall prevalence of healthy eating was higher after computed tomographic angiography (P=0.002) while obese/overweight status was lower (P=0.040). Positive initial test results and revascularization demonstrated stronger associations with preventive medications and lifestyle than test type. Medication initiation was not associated with fewer cardiovascular events. CONCLUSIONS: Positive initial test results and revascularization are primary drivers of changes in preventive medical and lifestyle practices, with test type making secondary contributions. However, substantial opportunities exist to further reduce cardiovascular risk. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01174550.

Mass-casualty victim "surge" management. Preparing for bombings and blast-related injuries with possibility of hazardous materials exposure.

Bombings and other blast-related events place severe demands on pre-hospital and in-hospital systems. The resulting surge of victims can overwhelm the resources of any facility not prepared for such an event. The September 11 terrorist attacks underscore the urgency of our need for preparedness. The challenges become even more daunting when there is possible hazmat exposure as well; this means that adequate and rapid disposition of victims is even more critical in order to avoid contamination of hospitals systems or whole communities. Federal agencies have been designated and federal mandates have been issued to address mass casualty events, but federal or even regional systems cannot respond in time to address the massive and immediate needs generated by an explosion. Local communities must take the lead in developing incident command systems for initial management of such events. Hospital and pre-hospital providers play a key role in such planning. Ultimate management and disposition of large numbers of casualties, especially if contaminated, cannot follow standard patient management protocols; new protocols are needed. To avoid a total, overwhelming break down of in-hospital resources, hospitals need to assume a lead role in addressing such issues in their local communities.

Risk stratification in chest pain patients undergoing nuclear stress testing: the Erlanger Stress Score.

BACKGROUND: Studies have individually reported the relationship of age, cardiac risk factors, and history of preexisting coronary artery disease (CAD) for predicting acute coronary syndromes in chest pain patients undergoing cardiac stress testing. In this study, we investigate the interplay of all these factors on the incidence of acute coronary syndromes to develop a tool that may assist physicians in the selection of appropriate chest pain patients for stress testing. METHODS: Retrospective analysis of a prospectively acquired database of consecutive chest pain patients undergoing nuclear stress testing. Backward stepwise logistic regression was used to develop a model for predicting risk of 30-day acute coronary events (ACE) using information obtained from age, sex, cardiac risk factors, and history of preexisting CAD. RESULTS: A total of 800 chest pain patients underwent nuclear stress testing. ACE occurred in 74 patients (9.3%). Logistic regression analysis found only 6 factors predictive of ACE: age, male sex, preexisting CAD, diabetes, and hyperlipidemia. Area under the receiver operator characteristic curve of this model for predicting ACE was 0.767 (95% confidence interval, 0.719-0.815). There were no cases of ACE in the 173 patients with predicted probability estimates ≤2.5% (95% confidence interval, 0%-2.1%). CONCLUSIONS: A regression model using age, sex, preexisting CAD, diabetes, and hyperlipidemia is predictive of 30-day ACE in chest pain patients undergoing nuclear stress testing. Prospective studies need to be performed to determine whether this model can assist physicians in the selection of appropriate low-to-intermediate risk chest pain patients for nuclear stress testing.

Ice storm-related carbon monoxide poisonings in North Carolina: a reminder.

Severe winter weather, such as ice storms, that results in loss of electrical power, is frequently mentioned as a contributing factor in acute carbon monoxide (CO) poisoning. However, in our literature review, such events are infrequently reported. This article reports on such an event in which more than 200 patients were evaluated and treated at a single facility because of the crippling effects of an ice storm leading to prolonged loss of power and subsequent catastrophes with alternative heating and cooking sources. One hundred seventy-six patients were treated and subsequently released after Emergency Department-based treatment for CO exposure, and three patients were admitted. Eighteen patients were treated with hyperbaric treatments and discharged. Three others left before treatment was completed. Three cases representing varying levels of severity at presentation leading to differing treatment algorithms are discussed to demonstrate a suggested clinical decision pathway in the treatment of unintentional CO poisoning.