Utility of continuous electrocardiographic monitoring in pregnant women with cardiovascular disease

Background: Arrhythmias are a common complication in pregnant women with heart disease. While continuous electrocardiographic monitoring is a useful tool for diagnosis, it also has significant associated costs, and identifying which pregnant women are most likely to benefit from monitoring is an important goal. Methods: This is a retrospective observational study of pregnant adult women with heart disease cared for at an academic medical center between 2016 and 2020. Clinical information and ambulatory and inpatient monitoring results were abstracted from the electronic health record and descriptive statistics and T-tests were used to characterize the population. Results: A total of 258 pregnancies in 202 unique women were included. The most common type of cardiovascular disease was congenital heart disease (56.6%), followed by cardiomyopathy (11.2%). An ambulatory monitor was ordered in 26.7% of pregnancies in the antepartum period, and 26.1% of these had clinically significant findings. 46.4% of monitors resulted in a clinical management change, with the most common changes being no recommendation for intrapartum electrocardiographic monitoring (20.3%) and starting a new medication (14.5%). Continuous electrocardiographic monitoring was used in 54.8% of deliveries, and detected a significant arrhythmia in only 2 cases (0.1%). Conclusions: A symptom driven protocol for ambulatory monitoring in pregnancy yields abnormal findings in a significant proportion of patients, and nearly half trigger a change in clinical management. Intrapartum electrocardiographic monitoring has a low yield, with a significant arrhythmia detected in less than 1% of pregnancies in this cohort.