Author + information
- Received May 10, 2018
- Accepted May 24, 2018
- Published online November 19, 2018.
- aDepartment of Cardiology, Krishna Institute of Medical Sciences, Deemed University, Malakapur, Karad (Dist – Satara), Maharashtra, India
- bDepartment of Arrhythmia and Electrophysiology, CARE Hospital, Hyderabad, Telangana, India
- ↵∗Address for correspondence:
Dr. Calambur Narasimhan, Arrhythmia and Electrophysiology Services, CARE Hospital, Road No. 1, Banjara Hills, Hyderabad-500 034, India.
A 58-year-old female patient presented with monomorphic ventricular tachycardia (right bundle branch block with inferior axis). The baseline electrocardiogram was normal. Her 2-dimensional echocardiogram revealed a hyperechoic septum with preserved left ventricular systolic function (Figure 1A-H). Coronary angiography revealed nonobstructive coronary artery disease. Gadolinium-enhanced cardiac magnetic resonance imaging showed a mid-myocardial scar in the basal septum. Fluorodeoxyglucose-18 positron emission computed tomography (18FDG-PET CT) revealed myocardial (maximum standardized uptake value of 6.7) and mediastinal lymph node inflammation (maximum standardized uptake value of 11.4) (Figures 1C, 1E, and 1G). However, the patient refused to have a tissue biopsy. She was treated as a probable case of cardiac sarcoidosis. A single-coil, single-chamber active fixation lead implantable cardioverter-defibrillator (ICD) (Boston Scientific, Marlborough, Massachusetts) was implanted at the high right ventricular outflow tract due to extensive septal scar and inflammation. Bipolar sensing electrograms showed split potentials at that site (Figure 1A). The R-wave was 5.0 mV, and the pacing threshold was 1 V at 0.4-ms pulse width. The patient was started on steroids 3 weeks after device implantation. Follow-up device interrogation showed no further ventricular tachycardia. A repeat 18FDG-PET CT scan after 4 months of steroid therapy showed a reduction in cardiac inflammation (Figures 1D, 1F, and 1H). Follow-up bipolar sensing electrograms from the ICD lead showed disappearance of split potentials with an R wave of 4.5 mV and threshold of 1.0 V at 0.4-ms pulse width (Figure 1B).
This case highlights that split potentials or late potentials can be a marker of ongoing cardiac inflammation and may resolve with immunosuppressive therapy.
The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
All authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the JACC: Clinical Electrophysiology author instructions page.
- Received May 10, 2018.
- Accepted May 24, 2018.
- 2018 American College of Cardiology Foundation