Ecg lead placement

Capturing clear ECG/EKG signals is vital in gaining accurate insights and results. It can be a real challenge to record clean signals, especially when performing a 12 lead ECG. There are numerous elements to get right: the data recording equipment needs to be set up correctly, the subject needs to be comfortable, and you need to position the surface electrodes on the subject's torso and limbs precisely in order to get results that you can interpret accurately. Related: Here is our simple guide for correctly placing surface electrodes when performing a 12 lead ECG: Simple steps for correct 12 lead ECG placement: Prepare the skin Before placing your ECG electrodes, it is very important to prepare the subject's skin by wiping the chest area thoroughly with skin cleansing (alcohol) swabs. This removes any oil that may be on the skin and which can cause drift in your ECG/EKG signals. Once the skin is clean, find and mark the placements for the electrodes... Find and mark the placements for the electrodes: First, identify V1 and V2 Find the correct placement for the chest leads, starting with V1 and V2. It is especially important to correctly place V1 and V2 because the remaining chest leads are placed in relation to these. To determine the placement of V1 and V2, feel to identify the top of your subject's sternum. Approximately 4 centimeters below this, there is a ridge. This identifies the second intercostal space. Feeling down, you will come across the third and fourth interc...

• Gabriel M Khan • Dr Gabriel M Khan MB, BCh, MD (Queen's Belfast), FRCP (London) FRCP C, FACP, FACC, Associate Professor, Department of Medicine and Division of Cardiology, University of Ottawa, The Ottawa Hospital, Ottawa, Ontario, Canada • Correspondence to Dr Gabriel M Khan; DrKhanBooksgmail.com Objective Worldwide, more than 50 million ECGs are carried out annually. Studies show that the standard wrist–ankle placement method may produce poor quality ECGs. Factors including limb movement, tremor, anxiety, cold extremities cause artefacts (distortions of the baseline and ECG waveforms). A problem exists. Physicians face a challenge interpreting poor quality ECGs. Diagnostic delays occur. Patients are subjected to recalls; compassion initiated this study. Torso (modified) leads are favoured as they provide rapid acquisition of better quality ECGs, but cause erroneous electrocardiography. Investigators have not attempted to correct these errors. This study analyses the errors and aims to rectify them. Methods Our pilot and other studies indicated that torso electrodes placed close to the heart cause an increase in R wave amplitude >3 mm in inferior leads that results in disappearance of inferior infarcts; a decrease >3 mm in 1 and aVL may cause false lateral infarcts. We hypothesised that finding electrode placements that do not cause alterations in R wave amplitude should correct these problems. Several electrode placements were assessed to obtain ECGs identical with the...

Misplacement of V1 and V2: Don’t let this mistake mess up your ECG interpretation! The proper location of V1 and V2 have not changed in many decades. They are located in the 4 th intercostal space, just right and left, respectively, of the sternum. It is fairly easy to determine this spot using the angle of Louis as a landmark. However, V1 and V2 were being misplaced pretty much right after being invented. This error in lead positioning usually produces trivial changes in the QRS pattern in those leads, and thus no real change in ECG interpretation. But certain erroneous ECG patterns can be generated, and it is important to recognize lead misplacement as a potential cause. Figure 1: V1 and V2 placed too high (1a) with resolution (1b) Figure 1a: V1 and V2 are placed too high, the P wave in V1 is fully negative (red arrow), and the P wave in V2 is biphasic (red star). Figure 1b: The leads are placed at their proper location, V1 shows a mostly-upright biphasic P (green arrow) and a fully upright P in V2 (green star). Figure 3: Young woman with atypical chest pain. Young woman presents with atypical chest pain. Negative D-dimer, but clinician noted the IRBBB in first ECG (figure 3a), raising suspicion for a PE, and a CTA was ordered. However, V1 and V2 had been placed in the 2nd intercostal space. When the ECG was repeated with V1 and V2 in 4th intercostal space (figure 3b) the IRBBB pattern resolved. Note that the P wave in V2 is fully positive when leads are correctly locate...

• • Paediatric ECG lead placement • • Placement of paediatric ECG leads In young children, the right ventricle normally extends to the right side of the sternum. To appropriately display right ventricular potentials, ECGs for children in the under five-year age group must include an alternate lead ( ‘V4R’) on the right side of the chest, at a point analogous to the left-sided V4. Precordial leads: • V1: 4th intercostal space, right sternal border • V2: 4th intercostal space, left sternal border • V3: midway between V2 and the placement of V4 in adults (5th intercostal space, left mid-clavicular line) • V4R: 5th intercostal space, right mid-clavicular line. Use this lead for V4R, must label as such on ECG. • V5: anterior axillary line, same horizontal plane as V4 • V6: mid-axillary line, same horizontal line as V4 Limb leads: • Place on top part of arm or leg (less muscle interference)

1. The Standard 12 Lead ECG The standard 12-lead electrocardiogram is a representation of the heart's electrical activity recorded from electrodes on the body surface. This section describes the basic components of the ECG and the lead system used to record the ECG tracings. Topics for study: • • ECG Waves and Intervals: What do they mean? • P wave: the sequential activation (depolarization) of the right and left atria • QRS complex: right and left ventricular depolarization (normally the ventricles are activated simultaneously) • ST-T wave: ventricular repolarization • U wave: origin for this wave is not clear - but probably represents "afterdepolarizations" in the ventricles • PR interval: time interval from onset of atrial depolarization (P wave) to onset of ventricular depolarization (QRS complex) • QRS duration: duration of ventricular muscle depolarization • QT interval: duration of ventricular depolarization and repolarization • RR interval: duration of ventricular cardiac cycle (an indicator of ventricular rate) • PP interval: duration of atrial cycle (an indicator of atrial rate) Orientation of the 12 Lead ECG It is important to remember that the 12-lead ECG provides spatial information about the heart's electrical activity in 3 approximately orthogonal directions: • Right ⇔ Left • Superior ⇔ Inferior • Anterior ⇔ Posterior Each of the 12 leads represents a particular orientation in space, as indicated below (RA = right arm; LA = left arm, LL = left foot): Bipolar...

• Gabriel M Khan • Dr Gabriel M Khan MB, BCh, MD (Queen's Belfast), FRCP (London) FRCP C, FACP, FACC, Associate Professor, Department of Medicine and Division of Cardiology, University of Ottawa, The Ottawa Hospital, Ottawa, Ontario, Canada • Correspondence to Dr Gabriel M Khan; DrKhanBooksgmail.com Objective Worldwide, more than 50 million ECGs are carried out annually. Studies show that the standard wrist–ankle placement method may produce poor quality ECGs. Factors including limb movement, tremor, anxiety, cold extremities cause artefacts (distortions of the baseline and ECG waveforms). A problem exists. Physicians face a challenge interpreting poor quality ECGs. Diagnostic delays occur. Patients are subjected to recalls; compassion initiated this study. Torso (modified) leads are favoured as they provide rapid acquisition of better quality ECGs, but cause erroneous electrocardiography. Investigators have not attempted to correct these errors. This study analyses the errors and aims to rectify them. Methods Our pilot and other studies indicated that torso electrodes placed close to the heart cause an increase in R wave amplitude >3 mm in inferior leads that results in disappearance of inferior infarcts; a decrease >3 mm in 1 and aVL may cause false lateral infarcts. We hypothesised that finding electrode placements that do not cause alterations in R wave amplitude should correct these problems. Several electrode placements were assessed to obtain ECGs identical with the...

• • Paediatric ECG lead placement • • Placement of paediatric ECG leads In young children, the right ventricle normally extends to the right side of the sternum. To appropriately display right ventricular potentials, ECGs for children in the under five-year age group must include an alternate lead ( ‘V4R’) on the right side of the chest, at a point analogous to the left-sided V4. Precordial leads: • V1: 4th intercostal space, right sternal border • V2: 4th intercostal space, left sternal border • V3: midway between V2 and the placement of V4 in adults (5th intercostal space, left mid-clavicular line) • V4R: 5th intercostal space, right mid-clavicular line. Use this lead for V4R, must label as such on ECG. • V5: anterior axillary line, same horizontal plane as V4 • V6: mid-axillary line, same horizontal line as V4 Limb leads: • Place on top part of arm or leg (less muscle interference)

Misplacement of V1 and V2: Don’t let this mistake mess up your ECG interpretation! The proper location of V1 and V2 have not changed in many decades. They are located in the 4 th intercostal space, just right and left, respectively, of the sternum. It is fairly easy to determine this spot using the angle of Louis as a landmark. However, V1 and V2 were being misplaced pretty much right after being invented. This error in lead positioning usually produces trivial changes in the QRS pattern in those leads, and thus no real change in ECG interpretation. But certain erroneous ECG patterns can be generated, and it is important to recognize lead misplacement as a potential cause. Figure 1: V1 and V2 placed too high (1a) with resolution (1b) Figure 1a: V1 and V2 are placed too high, the P wave in V1 is fully negative (red arrow), and the P wave in V2 is biphasic (red star). Figure 1b: The leads are placed at their proper location, V1 shows a mostly-upright biphasic P (green arrow) and a fully upright P in V2 (green star). Figure 3: Young woman with atypical chest pain. Young woman presents with atypical chest pain. Negative D-dimer, but clinician noted the IRBBB in first ECG (figure 3a), raising suspicion for a PE, and a CTA was ordered. However, V1 and V2 had been placed in the 2nd intercostal space. When the ECG was repeated with V1 and V2 in 4th intercostal space (figure 3b) the IRBBB pattern resolved. Note that the P wave in V2 is fully positive when leads are correctly locate...

Capturing clear ECG/EKG signals is vital in gaining accurate insights and results. It can be a real challenge to record clean signals, especially when performing a 12 lead ECG. There are numerous elements to get right: the data recording equipment needs to be set up correctly, the subject needs to be comfortable, and you need to position the surface electrodes on the subject's torso and limbs precisely in order to get results that you can interpret accurately. Related: Here is our simple guide for correctly placing surface electrodes when performing a 12 lead ECG: Simple steps for correct 12 lead ECG placement: Prepare the skin Before placing your ECG electrodes, it is very important to prepare the subject's skin by wiping the chest area thoroughly with skin cleansing (alcohol) swabs. This removes any oil that may be on the skin and which can cause drift in your ECG/EKG signals. Once the skin is clean, find and mark the placements for the electrodes... Find and mark the placements for the electrodes: First, identify V1 and V2 Find the correct placement for the chest leads, starting with V1 and V2. It is especially important to correctly place V1 and V2 because the remaining chest leads are placed in relation to these. To determine the placement of V1 and V2, feel to identify the top of your subject's sternum. Approximately 4 centimeters below this, there is a ridge. This identifies the second intercostal space. Feeling down, you will come across the third and fourth interc...

1. The Standard 12 Lead ECG The standard 12-lead electrocardiogram is a representation of the heart's electrical activity recorded from electrodes on the body surface. This section describes the basic components of the ECG and the lead system used to record the ECG tracings. Topics for study: • • ECG Waves and Intervals: What do they mean? • P wave: the sequential activation (depolarization) of the right and left atria • QRS complex: right and left ventricular depolarization (normally the ventricles are activated simultaneously) • ST-T wave: ventricular repolarization • U wave: origin for this wave is not clear - but probably represents "afterdepolarizations" in the ventricles • PR interval: time interval from onset of atrial depolarization (P wave) to onset of ventricular depolarization (QRS complex) • QRS duration: duration of ventricular muscle depolarization • QT interval: duration of ventricular depolarization and repolarization • RR interval: duration of ventricular cardiac cycle (an indicator of ventricular rate) • PP interval: duration of atrial cycle (an indicator of atrial rate) Orientation of the 12 Lead ECG It is important to remember that the 12-lead ECG provides spatial information about the heart's electrical activity in 3 approximately orthogonal directions: • Right ⇔ Left • Superior ⇔ Inferior • Anterior ⇔ Posterior Each of the 12 leads represents a particular orientation in space, as indicated below (RA = right arm; LA = left arm, LL = left foot): Bipolar...