Correspondence: “Electrocardiography in a Patient with Deep Brain Stimulation”

Dear Editor, We read with great interest the image published by Mirg and Rajan regarding the electrocardiogram (ECG) artefacts in a patient with deep brain stimulation (DBS).1 DBS delivers high-frequency electrical stimulation to specific brain sites through implanted electrodes. The electrical stimulation leads to the generation of electromagnetic fields (EMFs), which can interfere with other electrical recording devices such as ECG and electroencephalogram, generating artefacts, which may lead to misinterpretation of normal findings. With the number of DBS surgeries rising, it is pertinent for general physicians, neurologists, and cardiologists to know about the different artefacts related to DBS. The authors have reported a case of a 61-year-old with DBS in the subthalamic nucleus with ECG artefacts. However, they have neither described the artefact nor have they marked it in the image. The artefacts mentioned most likely represent the atrial flutter-like changes noticed in lead I, III, aVF, aVR, aVL, V1, V2, and V3 leads. Another limitation of the article is the absence of a possible explanation for the cause of artefacts. The EMF generated by neurostimulation acts as a cause of the generation of artefacts in the ECG.2 The extent of field generation depends on the configuration of the DBS electrodes. In a monopolar setup, the EMF extends from the implanted electrode to the IPG, affecting the precordial region and causing artifacts that interfere with nearby stimulation and recording devices. Bipolar configuration confines the EMF more locally, seldom reaching the precordial area and thus producing far fewer artifacts and interferences. In their prospective analysis of 4096 ECG leads in 33 DBS patients, Mruk et al.3 found monopolar configuration to be significantly associated with the presence of artifacts. Correct interpretation of ECG is important, and physicians need to be aware of the artifacts associated with DBS. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.