Materials and Methods:
A retrospective study was conducted at the Prenatal Diagnostic and Intervention center in the Department of Obstetrics and Gynecology at Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), a tertiary referral Institute of National Importance in Puducherry, South India, from June 2016 to July 2022. During the hospital visit, patients are required to sign a form granting consent for the analysis of their pregnancy data for scientific purposes, in accordance with the existing ethical guidelines. As this study involved a retrospective review of data collected for clinical purposes, formal approval from an ethics committee was not sought. A total of 55 cases of reported intermittent or sustained fetal arrhythmias were identified during the study period of 7 years, with review of the medial records and Fetal Echocardiography images and cine-loops. The cases of non-sustained rhythm abnormalities were excluded and the 40 cases with sustained rhythm abnormalities were included in the study. Pregnancy and cardiac outcomes were acquired from the system data base and case files.
The analysis involved the examination of fetal arrhythmia types, clinical characteristics, and outcomes, as well as outlining a management approach. Fetal arrhythmias were categorized into irregular rhythms, tachyarrhythmia, and bradyarrhythmia, with definitions5 provided in Table 1 . A fetal medicine expert re-evaluated the images and cine loops to confirm and assign final diagnoses. The study utilized detailed transabdominal fetal echocardiography, performed by a single professional using the Voluson E8 from General Electronics. M-mode and Doppler studies complemented 2-D assessments. Management decisions were made considering gestational period, type, and severity of rhythm disturbance, and the presence of structural abnormalities. Descriptive analysis was presented for numerical variables as mean, standard deviation, or median, while categorical variables were expressed in numbers and percentages. Due to the small sample size, statistical and multivariate analyses were not conducted.