Identification of the optimal electrocardiographic leads for detecting acute epicardial injury in acute myocardial infarction.

Current coronary care electrocardiographic (ECG) monitoring techniques are aimed at detection of cardiac arrhythmias rather than myocardial ischemia. However, in patients with acute myocardial infarction (AMI) who undergo reperfusion therapy, monitoring ST-segment deviation could provide an early noninvasive indicator of coronary artery reocclusion. In this study, the admission 12-lead ECGs of patients with initial AMI were used to propose optimal lead locations for ST-segment monitoring. The study population was selected from consecutive Duke University Medical Center admissions during 1965 to 1981 who met the following inclusion criteria: chest pain for no more than 8 hours, initial AMI documented by ECG and 3 of 4 enzyme criteria, greater than or equal to 0.1 mV (1 mV = 10 mm) of ST elevation in at least 1 of the standard 12 leads (not aVR) on admission ECG, and no ECG evidence of conduction disturbances, ventricular hypertrophy or tachycardia. ST-segment deviation was quantified; AMI location was assigned based on the lead with maximal deviation. Of the 80 patients who had an inferior AMI, lead III was both the most frequent location for ST elevation (94%) and the most common site with maximal ST deviation. Lead V2 had the highest incidence of ST-segment depression (60%). In the 68 patients who had an anterior AMI, lead V2 had the highest frequency of ST elevation (99%). Leads V2 and V3 were the most common sites of maximal elevation. Thus, for monitoring ST deviation, leads III and V2 may be superior to leads II and V1, which are commonly used in arrhythmia monitoring.(ABSTRACT TRUNCATED AT 250 WORDS)

Supporting nursing innovations in a cost-conscious environment.

Our rapidly changing health care environment requires critical care nurses to develop creative and innovative approaches to patient care. Empowering and enabling these nurses are the only ways that health care institutions will be able to meet the challenges of the future. This article describes two examples of innovations that have contributed to cost containment within a coronary care unit.

Heart Center nursing research: a team effort. Heart Center Nursing Research Work Group Members.

Our Heart Center staff identified a need to become more involved in nursing research and evidence based practice. A lack of awareness of the research process and current Heart Center nursing research studies resulted in low patient enrollment. To overcome these challenges a Heart Center Nursing Research Work Group (HCNRWG) was created with support of management. Staff nurses from each unit within the Heart Center participated, and sessions were facilitated by an Assistant Nurse Manager and Clinical Nurse Specialist. Advanced Practice Nurses functioned as consultants. The goal was to support nurses in developing a greater understanding of research and promote nursing research and visibility. Results included the development of research notebooks, inclusive of medical, nursing, and collaborative research projects, "Ask Me About Nursing Research" buttons, and mechanisms for study enrollment for each unit. Writing workshops were held to assist nurses with the preparation of abstracts, manuscripts, and research. A "hot line" was established to answer questions and informational packets and newsletters were distributed to staff and leadership quarterly. An increased awareness of research among the health care team has ensued. Meeting attendance has tripled, more nursing abstracts have been submitted to national conferences and there are ongoing research studies on all heart center units with increased patient enrollment.

New strategies in the management of acute coronary syndromes.

Advances in the understanding of acute coronary syndromes have occurred rapidly in the last 5 years and have dramatically changed the way patients are evaluated, diagnosed, and managed. Medical advances, such as antiplatelet and antithrombin agents and growing databases on interventional outcomes have created a new world of therapeutic options for the spectrum of ischemic heart disease. As more options become available, nurses are under increasing pressure to stay abreast of what these options have to offer patients, and which patients benefit most from each therapeutic approach. The purpose of this article is to review the newest therapies for acute coronary syndromes, including GP IIb/IIIa inhibitors, low molecular weight heparins, and direct thrombin inhibitors, and discuss indications and contraindications for each of these therapies. Changes in diagnostic approach using troponin T and I are also presented.

Experience with the use of tPA in the treatment of acute myocardial infarction.

Early experience with the use of tissue plasminogen activator (tPA) in acute myocardial infarction is reviewed, including comparisons with other thrombolytic agents, a summary of hemorrhagic complications associated with its use, and the rationale for adjunctive therapeutic strategies. The use of tPA has been associated with improvement in left ventricular function, a lower mortality, and a decrease in congestive heart failure signs and symptoms. A protocol for evaluation of patients with possible myocardial infarction for thrombolytic therapy is presented. Consideration must be given to other possible diagnoses, and the ECG must be evaluated carefully to ensure that appropriate criteria are met. Risk factors for hemorrhagic complications include recent trauma, surgery, gastrointestinal and genitourinary bleeding, stroke, and focal neurologic findings. Greater benefit of therapy is expected in patients with larger infarcts who have more marked ST segment changes or evidence of hemodynamic compromise, especially when they are treated early after the onset of symptoms (within the first several hours). Adjunctive measures that can be considered in the emergency department include prophylactic lidocaine, IV nitroglycerin, beta blockade, aspirin, volume replacement and monitoring for dysrhythmias, bleeding, and recurrent ischemia. A comprehensive understanding of these rapidly evolving concepts will assist the emergency physician in the evaluation and management of patients with acute myocardial infarction.