12-Lead EKG Electrode Placement and Artifacts
Ten electrodes make a 12-lead EKG: four on the limbs and six across the chest, V1 and V2 in the 4th intercostal space and V4-V6 level with the 5th intercostal space.
Electrode positions with diagram coordinates
| electrode | anatomic location |
|---|---|
| V1 | 4th intercostal space, right sternal border |
| V2 | 4th intercostal space, left sternal border |
| V3 | Halfway between V2 and V4 |
| V4 | 5th left intercostal space, midclavicular line |
| V5 | Same level as V4, left anterior axillary line |
| V6 | Same level as V4 and V5, left midaxillary line |
| RA | Right arm (limb) |
| LA | Left arm (limb) |
Preview only. 2 more rows in this section. The full sheet also covers: US (AHA) limb lead-wire colours; Paper speed and calibration; Common artifacts and fixes.
Sources
- Perez-Riera AR, et al. Main artifacts in electrocardiography. Ann Noninvasive Electrocardiol. 2018;23:e12494 (artifact, lead-reversal and electrode-position sections) · Wiley via PubMed Central
- Abobaker A, Rana RM. V1 and V2 pericordial leads misplacement and its negative impact on ECG interpretation and clinical care. Ann Noninvasive Electrocardiol. 2021;26:e12844 · Wiley via PubMed Central (CC BY 4.0)
- Modified precordial lead ECG SafOne on electrocardiography recordings (artefact discussion) · PubMed Central
- Electrocardiography (ECG; EKG) (full review May 2026): lead system, standard ECG components, additional precordial leads, Holter monitor, event recorders · Merck Manual Professional Version
- Modified Torso vs Distal Limb Electrode Placement for Performing ECGs in Children: A Method Comparison Study (Children's Hospital of Philadelphia) · PubMed Central
- A Study of the Frequency of Lead Reversal at a Tertiary Care Institution (IEC limb-electrode colour convention) · PubMed Central
- ARIC Study Manual 5: Electrocardiography (electrode placement, fault detection, technical quality, AC interference and muscle tremor) · Atherosclerosis Risk in Communities Study (NHLBI) via NCBI dbGaP