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The challenge to anatomically proper placement of precordial leads V1 and V2. (A) Format of typical instructional diagram depicting correct location of V1 and V2, parasternally at the fourth intercostal space, in relation to an underlying rib cage. (B) Real-world target for placement of precordial leads V1 and V2 lacks visual markers of rib cage. The conventional approach to overcoming this perceptual gap involves searching by palpation for a horizontal bony ridge, the sternal angle (panel A), to help demarcate the second intercostal space, from which one can then count downward to the fourth intercostal space.
Source publication
Misplacement of right precordial electrocardiogram (ECG) electrodes superiorly is a prevalent procedural error that may lead to false findings of T-wave inversion or QS complexes in V2-possibly triggering wasteful utilization of health care resources. Standard technique for proper placement of V1-V2 entails initial palpation for the sternal angle,...
Contexts in source publication
Context 1
... diagramming the anatomically precise positions for V1 and V2 commonly depict the loci for these electrodes in relation to an underlying rib cage, as generically illustrated in Figure 1A (37)(38)(39)(40)(41)(42)(43)(44)(45)(46). In a real live patient, however, one encounters a torso typically devoid of any visual markers for ribs or interspaces ( Figure 1B). ...
Context 2
... diagramming the anatomically precise positions for V1 and V2 commonly depict the loci for these electrodes in relation to an underlying rib cage, as generically illustrated in Figure 1A (37)(38)(39)(40)(41)(42)(43)(44)(45)(46). In a real live patient, however, one encounters a torso typically devoid of any visual markers for ribs or interspaces ( Figure 1B). Although not widely described in standard texts, the traditional technique for overcoming this perceptual gap entails searching by palpation for the horizontal bony ridge between the manubrium and body of the sternum, that is, the sternal angle (of Louis), serving as anatomic landmark for the second ICS ( Figure 1A), from which one can then count downward to the fourth ICS to affix leads V1 and V2 (36,(46)(47)(48)(49). ...
Context 3
... a real live patient, however, one encounters a torso typically devoid of any visual markers for ribs or interspaces ( Figure 1B). Although not widely described in standard texts, the traditional technique for overcoming this perceptual gap entails searching by palpation for the horizontal bony ridge between the manubrium and body of the sternum, that is, the sternal angle (of Louis), serving as anatomic landmark for the second ICS ( Figure 1A), from which one can then count downward to the fourth ICS to affix leads V1 and V2 (36,(46)(47)(48)(49). It is acknowledged that execution of this technique can be challenging (10,49). ...
Citations
... A má colocação dos eletrodos de ECG precordial superiormente é um erro de procedimento prevalente. (Lehmann, 2012). As derivações V1 e V2 do ECG precordial costumam estar mal colocadas. ...
Objetivo: Analisar o registro eletrocardiográfico diante da intervenção no posicionamento dos eletrodos no tórax comparada ao método standard. Método: Ensaio clínico controlado, simples cego, realizado com 41 pacientes, que compuseram o grupo controle e intervenção, gerando registros que foram laudados por dois profissionais de saúde, proficientes em cardiologia. Resultados: Foram analisados 82 eletrocardiogramas, tendo como direcionamento os protocolos controle e intervenção, nos quais constavam a descrição das técnicas correta e incorreta, respectivamente. A maioria das variáveis estudadas não apresentou diferença estatística significativa quanto aos laudos analisados diante da comparação entre os protocolos aplicados. A exceção foi referente à onda P, apresentando-se negativa em V1 quando deveria estar positiva, evidenciada na comparação entre 14 pares de eletrocardiogramas (P = 0,003). Conclusão: O posicionamento incorreto dos eletrodos afetou o registro da derivação V1. Considerando-se o eletrocardiograma de doze derivações usualmente realizado na prática clínica, salienta-se quanto ao possível confundimento devido aos marcos anatômicos base de outros procedimentos, como, por exemplo, os focos de ausculta cardíaca. Sugere-se o desenvolvimento de critérios adicionais e tecnológicos para o reconhecimento e detecção de erros de localização do eletrodo, bem como a capacitação profissional ser condição sine qua non para a realização do exame de eletrocardiografia. (ReBEC - NCT: RBR-9h4tp3).
... The studies [12,29] indicated, next to the optimal location of ECG electrodes, an important aspect affecting the Se of the proposed diagnostic methods. It is the precision of placing the ECG electrodes on the thoracic surface, which significantly affects the diagnosis [27,30,31]. In the proposed optimal ECG electrode systems, the most attention should be paid to the correct placement of electrodes located near the precordial electrode V 4 , for which small ECG electrode displacements significantly affect the morphology changes of the registered ECG signal [12,29]. ...
The diagnostic value of an ECG exercise test in diagnosis of ischemic heart disease (IHD) is limited. We investigated whether it is possible to develop a method for diagnosis of IHD which uses a low number of optimal ECG leads and has a higher diagnostic efficiency than conventional exercise ECG. This study was carried out on 43 patients. The 67-lead high-resolution ECG was recorded at rest and during exercise. The diagnostic value of ST segment depression (ΔST60) and T-wave morphology change (δT) determined in optimized ECG lead configurations was higher than for the standard 12-lead ECG. The best results were obtained for δT determined from 6 ECG electrode locations where sensitivity and specificity were 70% and 69% whereas for the standard exercise ECG were 63% and 62%, respectively. The small number of ECG leads used allows for easy hardware implementation of the methods for use in clinical settings.
... Fuente: Errores y artefactos comunes en el EKG. García Niebla.Existen otros métodos como la "maniobra HN" que proporciona un enfoque visual para identificar el segundo EI descrita por Lehmann et al10 . Los libros de texto de electrocardiografía contienen poca o ninguna información sobre los efectos de la mala colocación de los electrodos. ...
INTRODUCCIÓN: una correcta técnica de realización del electrocardiograma es fundamental para evitar errores diagnósticos. Un amplio porcentaje de los profesionales sanitarios son incapaces de identificar la ubicación correcta de los electrodos V1 y V2. Esto puede dar lugar a morfologías y patrones electrocardiográficos que no son reales provocando sobre el paciente procedimientos que no son necesarios.
MATERIAL Y MÉTODOS: presentamos el caso de un paciente de 37 años que fue traído en UVI móvil a nuestro Servicio de Urgencias por dolor torácico y palpitaciones. El paciente padece este episodio con frecuencia debido a una miopericarditis recidivante. En esta ocasión se solicitó el ingreso en la unidad de cuidados intensivos por presentar un patrón de bloqueo de rama derecha de nueva aparición.
RESULTADOS: tras comparar el electrocardiograma de la UVI móvil con uno previo y el nuestro actual (ambos con colocación correcta de electrodos) se concluyó que el nuevo patrón de bloqueo de rama derecha fue provocado por una mala colocación de electrodos. Finalmente el paciente ingresó en Hospitalización.
DISCUSIÓN - CONCLUSIONES: es importante que el profesional sanitario que realiza los electrocardiogramas identifique de manera correcta el cuarto espacio intercostal tomando como referencia el ángulo de Louis. Si los electrodos precordiales se colocan de manera incorrecta pueden aparecer alteraciones en el voltaje de las ondas y 3 patrones electrocardiográficos descritos que afectan a las derivaciones V1 y V2.
... T wave memory [25], and subtle differences in positioning the precordial electrodes, i.e. ECG reproducibility [26]. Anatomic predisposition, particularly in women, may affect lead positioning, and thus alter the presence and distribution of leads with TWI ( Figure 3). ...
Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is considered a progressive cardiomyopathy. However, data on the clinical features of disease progression are limited. The aim of this study was to assess 12-lead surface electrocardiographic (ECG) changes during long-term follow-up, and to compare these findings with echocardiographic data in our large cohort of patients with ARVC/D.
Baseline and follow-up ECGs of 111 patients from three tertiary care centers in Switzerland were systematically analyzed with digital calipers by two blinded observers, and correlated with findings from transthoracic echocardiography.
The median follow-up was 4 years (IQR 1.9-9.2 years). ECG progression was significant for epsilon waves (baseline 14% vs. follow-up 31%, p = 0.01) and QRS duration (111 ms vs. 114 ms, p = 0.04). Six patients with repolarization abnormalities according to the 2010 Task Force Criteria at baseline did not display these criteria at follow-up, whereas in all patients with epsilon waves at baseline these depolarization abnormalities also remained at follow-up. T wave inversions in inferior leads were common (36% of patients at baseline), and were significantly associated with major repolarization abnormalities (p = 0.02), extensive echocardiographic right ventricular involvement (p = 0.04), T wave inversions in lateral precordial leads (p = 0.05), and definite ARVC/D (p = 0.05).
Our data supports the concept that ARVC/D is generally progressive, which can be detected by 12-lead surface ECG. Repolarization abnormalities may disappear during the course of the disease. Furthermore, the presence of T wave inversions in inferior leads is common in ARVC/D.
... To date, no comparison of the static supine 12-lead ECG to the semi-recumbent and upright-position ECGs in the clinical setting has been reported. 15 When an abnormality appears on a preoperative ECG, it may lead to cancellation or delay in scheduled surgery. In clinical settings, the false diagnosis can trigger unnecessary and possibly expensive non-invasive procedures intended to characterize the extent of cardiac disease. ...
... Lehman et al. 15 had a positive outcome in their study. The hand-to-neck (H/N) manoeuvre technique might have merit as an educational tool to reduce the likelihood of ECG procedure-related misdiagnosis of heart disease. ...
Background
Coronary heart disease (CHD) patients require monitoring through ECGs; the 12-lead electrocardiogram (ECG) is considered to be the non-invasive gold standard. Examples of incorrect treatment because of inaccurate or poor ECG monitoring techniques have been reported in the literature. The findings that only 50% of nurses and less than 20% of cardiologists correctly place leads V1 and V2 of a standard 12-lead ECG is of great concern.
Objective
The review discusses the evidence base underpinning the use of 12-lead ECG electrode placement on patients with suspected heart disease and summarizes the results of 10 research papers.
Methods
The Cumulative Index to Nursing and Allied Health Literature (CINAHL), the British Nursing Index (BNI), Embase and Medline were searched, from 2000 up to May 2012 using the key words ‘electrocardiography’, ‘positioning’, ‘electrodes’, ‘electrocardiogram’, ‘lead placement’ and ’12-lead ECG’. The search was limited to studies in the English language. The quality of each study was rated against set inclusion and exclusion criteria.
Results
All the studies found that the incorrect connection of the electrode cables can alter ECG patterns simulating or concealing abnormalities, such as myocardial infarction (MI). Adherence to correct anatomical precordial lead placement methodology continues to be limited, especially with respect to leads V1 and V2 at the fourth intercostal space (ICS), which can potentially yield recorded waveforms that mimic the ECG diagnosis of septal MI.
Conclusions
False ECG diagnosis of MI resulting from improper lead placement has the potential to trigger the wasteful use of healthcare resources and even cause harm to patients.
More than 1 million ECGs are recorded every day. This literature review examined the accuracy of electrode placement (EP) when acquiring a standard 12-lead electrocardiograph recording (STLER), and the consequences of inaccuracy. The findings showed that EP accuracy varies from 16–90%, and standards and guidelines on EP are not being adhered to. Poor EP can mean under- or overdiagnosis, which can increase morbidity and mortality, or mean that patients receive unnecessary treatment or hospitalisation. Mandatory, appropriate training and assessment, including before an operator is allowed to acquire a STLER and refresher training for ECG operators, are recommended.
Objectives:
To verify accurate placement of the precordial ECG leads by identifying the 4th and 5th intercostal spaces as a function of the length of the sternum. This should decrease the percentage of lead misplacement leading to misdiagnoses.
Methods:
The population consisted of patients and healthy volunteers. The proposed method compared palpation of the 4th and 5th intercostal spaces to a percentile of the sternal length. Location of the 4th and 5th intercostal space using a simple device was evaluated to assist in proper placement of the precordial leads to obtain accurate diagnosis.
Results:
The location of the 4th and 5th intercostal space is related to the length of the sternum. It is 77% of the sternal length that measures 15cm for the 4th intercostal space. The position of the V1 and V2 electrodes decreases to 57% when the sternal length is 26cm. Similar data was obtained to locate the 5th intercostal space with proper position of V4-V6 electrodes. Tables are provided to facilitate this process. An instrument was designed to measure the 4th and 5th intercostal space as a function of the sternal length.
Conclusions:
The location of the 4th and 5th intercostal space is identified based on the length of the sternum.
Awareness of the problem of false electrocardiographic diagnosis of septal infarction due to cranially misplaced precordial leads V1 and V2, a common technical error, is important because this pseudo-pathologic finding can trigger unnecessary medical procedures and have other adverse sequelae. The non-trivial nature of this problem is emphasized by the case of a patient in whom the misdiagnosis caused loss of an employment opportunity. We demonstrate how P wave morphology in lead V2 can aid the clinician in suspecting erroneous right precordial lead placement in cases of apparent septal infarction. Ultimately, improved education of health care personnel regarding accurate precordial lead positioning technique is needed to minimize the occurrence of this electrocardiographic misdiagnosis.
