Increased Cardiac Arrhythmia After Pregnancy‐Induced Hypertension: A South Korean Nationwide Database Study

Background Although pregnancy‐induced hypertension (PIH) is associated with an elevated cardiovascular risk, long‐term studies or prepregnancy baseline data are scarce. Therefore, using a large nationwide cohort with prepregnancy periodic health screening data, we investigated whether clinically significant arrhythmia incidence increases after PIH. Methods and Results Data were extracted from the Korea National Health Insurance database and combined with the National Health Screening Examination database; women who gave birth between 2007 and 2015 and underwent the national health screening test within a year before pregnancy were followed up until 2016. We excluded women who had a diagnosis of arrhythmia within 1 year before pregnancy. The primary outcome was significant arrhythmia during the year after delivery. Secondary analysis included only specific diagnostic codes of arrhythmia with clinical significance. Additionally, the risk of arrhythmia was stratified by the use of magnesium sulfate. Of 2 035 684 women (PIH; n=37 297 versus normotensive pregnancy; n=1 998 387), the PIH group had a higher prepregnancy risk profile and showed a higher incidence of arrhythmia than women with normotensive pregnancies within 1 year. Women with PIH had a significantly higher risk of atrial flutter/fibrillation and atrioventricular block, but not lethal arrhythmias. Other predictors of arrhythmia development included advanced maternal age and cesarean section. Stratified analysis showed a higher risk of arrhythmia with magnesium sulfate use. Conclusions PIH was significantly associated with the development of arrhythmia within 1 year after delivery. Nevertheless, the incidence of lethal arrhythmias was not increased by PIH. Arrhythmia, especially atrial fibrillation, may largely contribute to increasing the future cardiovascular risk in women with a PIH history.

Increased Risk of Meconium-Related Ileus in Extremely Premature Infants Exposed to Antenatal Magnesium Sulfate

<b><i>Introduction:</i></b> We experienced an increased incidence of meconium-related ileus (MRI) in extremely premature infants (EPIs) while adopting the antenatal magnesium sulfate (MgSO₄) protocol for fetal neuroprotection in our neonatal intensive care unit. This study aimed to test whether antenatal MgSO₄ use was associated with increased risk of MRI in EPIs. <b><i>Methods:</i></b> The incidences of complicated MRI requiring aggressive enema or surgical intervention and other intestinal complications were compared among period 1 (January 2012–December 2013, <i>n</i> = 79), before adoption of the antenatal MgSO₄ protocol for fetal neuroprotection; period 2 (January 2014–March 2016, <i>n</i> = 72), when the protocol was adopted; and period 3 (April 2016–September 2018, <i>n</i> = 75), when the protocol was temporarily withdrawn due to concern regarding intestinal complications in EPIs. <b><i>Results:</i></b> Despite similar baseline clinical characteristics among infants across the study periods, the MRI and MRI with surgical treatment incidences were higher in period 2 than those in periods 1 and 3 (13% vs. 8% and 6%, <i>p</i> = 0.391, and 11% vs. 0% and 1%, <i>p</i> = 0.001, respectively). In multivariable analysis, exposure to antenatal MgSO₄ independently increased the risk of MRI (adjusted odds ratio, 3.8; 95% confidence interval, 1.4, 10.6). <b><i>Conclusion:</i></b> Antenatal MgSO₄ may increase the risk of MRI, frequently requiring surgical intervention, in EPIs with a gestational age of 25 weeks or less.