Fetal arrhythmias: Diagnosis and management

Uterine sacrifice in obstetric emergencies case series: Complex cases of fetal distress, labor challenges, and life-saving interventions

This study highlights the complexities and challenges in managing obstetric emergencies, detailing critical interventions and outcomes in various high-risk cases. A retrospective analysis was conducted on four high-risk obstetric cases, each characterized by distinct complications necessitating immediate medical interventions. The study specifically examined cases involving: Fetal Distress cases where fetal health was compromised, necessitating interventions such as emergency cesarean sections. Complex Labor Dynamics detailed examinations of labor complications such as obstructed labor, precipitate labor, or labor complicated by malpresentation. Early pregnancy complications analysis focused on emergencies arising in the first trimester or early second trimester, including ectopic pregnancies and complications in pregnancies with a history of multiple cesarean sections. Severe postpartum hemorrhage investigations into cases of significant blood loss post-delivery, which required interventions ranging from pharmacological management to surgical procedures like hysterectomy. The first case concerned a 28-year-old primigravida with fetal bradycardia and thick meconium, requiring an emergency cesarean section. Postoperative complications included gestational thrombocytopenia and anemia, necessitating a total abdominal hysterectomy for severe sepsis. The newborn showed good recovery, indicated by Apgar scores. In Case 2, the need for a hysterectomy following complications during the third stage of labor was likely due to the presence of Placenta Accreta Spectrum, specifically placenta accreta or increta. While a retained placenta typically can be managed with less invasive methods, the situation escalates when the placenta is abnormally adherent to, or deeply invasive into, the uterine muscle. This can lead to uncontrollable bleeding, making a hysterectomy necessary and justified as a life-saving measure to control the severe hemorrhage while the histology confirms the diagnosis for the placenta accreta. In the third case, the decision to perform a dilation and curettage over manual vacuum aspiration was influenced by several factors. Given the severity of the patient's hemorrhage and the presence of a suspicious echogenic structure, a dilation and curettage provided a more controlled environment for thorough evacuation and immediate bleeding control. This approach was also supported by the combination technique using both Karman aspiration and a curette, allowing for effective management of complicated cases, particularly in patients with a history of multiple cesareans and potential scar tissue. The fourth case involved a 37-year-old multipara with severe postpartum hemorrhage from uterine atony, treated with surgery and managed for diabetic ketoacidosis, leading to discharge on the fourth day. This underscores the urgency and complexity of managing obstetric emergencies effectively.

Fetal bradycardia in open versus fetoscopic prenatal repair of spina bifida

OBJECTIVE

To compare the occurrence of fetal bradycardia in open versus fetoscopic fetal spina bifida surgery.

METHODS

This is a single-institution retrospective cohort study of patients undergoing open (n = 25) or fetoscopic (n = 26) spina bifida repair between 2017 and 2022. From October 2017 to June 2020, spina bifida repairs were performed via an open classical hysterotomy, and from November 2020 to June 2022 fetoscopic repairs were performed following transition to this technique. Fetal heart rate (FHR) in beats per minute (bpm) was recorded via echocardiography every 15 min during the procedure. Cohort characteristics, fetal bradycardia and maternal physiologic parameters were compared between the groups.

RESULTS

Fetuses undergoing an open repair more frequently developed bradycardia defined as <110 bpm (32% vs. 3.8%, p = 0.008), and a trend was observed for FHR decreases more than 25 bpm from baseline (20% vs. 3.8%, p = 0.073). Profound bradycardia less than 80 bpm was rare, occurring in only three operations (two in open, one in fetoscopic repair) with two fetuses (one in each group) requiring emergency cesarean delivery.

CONCLUSION

When compared to open fetal surgery, fetal bradycardia occurred less frequently in fetoscopic surgery despite a significantly greater anesthetic exposure and the use of the intraamniotic carbon dioxide insufflation.

Hierarchical online contrastive anomaly detection for fetal arrhythmia diagnosis in ultrasound

Arrhythmia is a major cardiac abnormality in fetuses. Therefore, early diagnosis of arrhythmia is clinically crucial. Pulsed-wave Doppler ultrasound is a commonly used diagnostic tool for fetal arrhythmia. Its key step for diagnosis involves identifying adjacent measurable cardiac cycles (MCCs). As cardiac activity is complex and the experience of sonographers is often varied, automation can improve user-independence and diagnostic-validity. However, arrhythmias pose several challenges for automation because of complex waveform variations, which can cause major localization bias and missed or false detection of MCCs. Filtering out non-MCC anomalies is difficult because of large intra-class and small inter-class variations between MCCs and non-MCCs caused by agnostic morphological waveform variations. Moreover, rare arrhythmia cases are insufficient for classification algorithms to adequately learn discriminative features. Using only normal cases for training, we propose a novel hierarchical online contrastive anomaly detection (HOCAD) framework for arrhythmia diagnosis during test time. The contribution of this study is three-fold. First, we develop a coarse-to-fine framework inspired by hierarchical diagnostic logic, which can refine localization and avoid missed detection of MCCs. Second, we propose an online learning-based contrastive anomaly detection with two new anomaly scores, which can adaptively filter out non-MCC anomalies on a single image during testing. With these complementary efforts, we precisely determine MCCs for correct measurements and diagnosis. Third, to the best of our knowledge, this is the first reported study investigating intelligent diagnosis of fetal arrhythmia on a large-scale and multi-center ultrasound dataset. Extensive experiments on 3850 cases, including 266 cases covering three typical types of arrhythmias, demonstrate the effectiveness of the proposed framework.

Medication and ECG Patterns That May Hinder SPECT Myocardial Perfusion Scans

Coronary artery disease (CAD) is the leading cause of death followed by cancer, in men and women. With risk factors being endemic and the increasing costs of healthcare for management and treatment, myocardial perfusion imaging (MPI) finds a central role in risk stratification and prognosis for CAD patients, but it comes with its limitations in that the referring clinician and managing team must be aware of and use at their advantage. This narrative review examines the utility of myocardial perfusion scans in the diagnosis and management of patients with ECG alterations such as atrioventricular block (AVB), and medications including calcium channel blockers (CCB), beta blockers (BB), and nitroglycerin which may impact the interpretation of the exam. The review analyzes the current evidence and provides insights into the limitations, delving into the reasons behind some of the contraindications to MPI.

A rare case with fetal autoimmune heart block and KNCH2 variant-induced long QT syndrome: a controversial opinion on prenatal management strategy

BACKGROUND

Among all fetal heart block patients, > 50% cases are associated with maternal autoimmune diseases, and such patients should receive treatment. However, nearly half of fetal heart block cases involve a mother with negative results following autoimmune antibody screening. A few studies have reported long QT syndrome (LQTS) can also present as a severe fetal bradycardia, which does not respond to fetal treatment. Herein, we reported a rare case of an infant who presented with high-degree autoimmune-mediated fetal atrioventricular block (AVB) with LQTS induced by a novel KCNH2 variant. This case led us to review our prenatal therapeutic strategy.

CASE PRESENTATION

A 1-year-old boy presented to our heart center having experienced syncope 5 times in the past year. He had previously presented with fetal bradycardia during the fetal stage from 27 + 3 gestational weeks. The fetal echocardiography demonstrated AVB (2:1 transmission). As the maternal autoimmune antibody results were positive, his mother had received dexamethasone treatment during pregnancy; subsequently, the fetal AVB had changed from 2:1 to 4:3 transmission with elevated ventricular beating rates. However, this patient was identified to have complete AVB after birth. The initial electrocardiogram and Holter measurements at hospital administration showed complete AVB, pleomorphic ventricular tachycardia, a prolonged QT interval (QT = 602 ms, corrected QT = 538 ms), and wide and deep inverted T-waves. Meanwhile, torsades de pointes could be observed in several transit ventricular tachycardias based on Holter monitoring review. Genetic testing revealed KCNH2 c.2483G > A variant-induced LQTS. An implantable cardioverter defibrillator device and permanent pacemaker were both considered as therapeutic alternations; his parents ultimately accepted the implantation of a permanent pacemaker.

CONCLUSIONS

For fetuses with autoimmune-mediated AVB, intrauterine treatment should still be pursued immediately. However, once the treatment outcomes are deemed unacceptable or unexpected, other genetic variant-related channelopathies should be highly suspected. If the fetus lacks a positive family history, fetal genetic testing should be recommended to improve the prognosis of such patients by introducing integrative therapeutic strategies between the prenatal and postnatal phases.

Perinatal outcomes of intrauterine fetal arrhythmias: A 10-year retrospective cohort study

Sustained fetal arrhythmia can produce life-threatening fetal distress, fetal hemodynamic compromise, hydrops fetalis, or even fetal death. Survivors may subsequently possess severe neurologic deficits. We conducted a retrospective observational study of pregnant women hospitalized with fetal arrhythmias from January 2011 to May 2020 at West China Second University Hospital, and fetal arrhythmias were diagnosed by specialists in cardiac ultrasonography. Of 90 cases of fetal arrhythmias, 14 (15.6%) were complicated by fetal congenital heart disease (CHD), 21 (23.33%) by fetal-hydrops, 15 (16.67%) cases by intrauterine therapy, and 6 (6.67%) by maternal auto-immune disease. In the fetal-hydrops group, the intrauterine therapy rate was significantly higher (47.62% vs 7.24%, P < .001) and the survival rate significantly lower (47.62% vs 92.75%, P < .001) than in the nonfetal hydrops group. A fetus whose arrhythmia was complicated by fetal-hydrops and CHD was delivered earlier and exhibited a lower cardiovascular profile score at diagnosis and birth, lower birth weight, and a higher rate of pregnancy termination than cases without hydrops and CHD (P < .05). Among the cases with maternal auto-immune disease, 71.43% (5/7) manifested fetal atrioventricular block. Multiple linear regression analysis revealed that 3 variables - fetal-hydrops (P < .001), body mass index (P = .014), and gestational age at diagnosis of fetal arrhythmia (P = .047) - were correlated with the gestational delivery age of arrhythmic fetuses. Parents should be counseled by the multidisciplinary team regarding the individualized management and prognosis of the arrhythmic fetus, and individualized fetal intrauterine therapy should be performed if necessary.

Case Report: A novel KNCH2 variant-induced fetal heart block and the advantages of fetal genomic sequencing in prenatal long-term dexamethasone exposure

Background: Fetal bradycardia is a common but severe condition. In addition to autoimmune-mediated fetal heart block, several types of channelopathies induce high-degree atrioventricular block (AVB). Long QT syndrome (LQTS) is a major cause of non-autoimmune-mediated fetal heart block. Due to the limitations of prenatal diagnostic technologies, LQTS is seldom identified unless fetal genetic screening is performed. Thus, long-term prenatal dexamethasone (DEX) exposure can become a challenge for these patients. We report on a rare case of a novel KCNH2 variant related to LQTS and associated with high-degree fetal AVB with long-term DEX exposure. This case led us to review our prenatal administration strategy for such patients.

Case Presentation: A fetus was identified with high-degree AVB (2:1 transduction at 28 + 2 gestational weeks). Typical tests of immune function in the pregnant woman were conducted including tests for thyroid function, rheumatic screening, autoimmune antibodies (such as anti-Ro/SSA and anti-La/SSB), and anti-nuclear antibodies (anti-ANA). Following the recommended protocol, the pregnant patient received DEX (0.75 mg/day) during pregnancy. Subsequently, the fetal AVB changed from 2:1 to prolonged AV intervals with ventricular tachycardia, which suggested a therapeutic benefit of DEX in some respects. However, a high-degree AVB with a significantly prolonged QTc interval was identified in the neonate following birth. Genetic testing revealed that a KCNH2 c.1868C&gt;A variant induced LQTS. The body length remained approximately -3.2 SD from the reference value after prenatal long-term DEX exposure, which indicated a developmental restriction. Additionally, the functional validation experiments were performed to demonstrate the prolonged duration of calcium transit both in depolarization and repolarization with the KCNH2 c.1868C&gt;A variant.

Conclusion: Genetic screening should be recommended in fetuses with autoimmune antibody negative high-degree AVB, especially for 2:1 transduction AVB and in fetuses with changes in fetal heart rhythm following initial DEX treatment. Genetic screening may help identify genetic variant–related channelopathies and avoid unexpected prenatal exposure of DEX and its possible long-term adverse postnatal complications.

Management of Implantable Cardioverter-Defibrillators during Pregnancy-A Systematic Review

Background: With the advent of implantable cardioverter-defibrillator (ICD) technology in recent decades, patients with inherited or congenital cardiomyopathy have a greater chance of survival into adulthood. Women with ICDs in this group are now more likely to reach reproductive age. However, pregnancy represents a challenge for clinicians, as no guidelines for the treatment of pregnant women with an ICD are currently available. Methods: To analyze this issue, we performed a systematic screening of the literature using the keywords: pregnancy with ICD, lead fracture in pregnancy, lead thrombi in pregnancy, ventricular tachycardia in pregnancy, inappropriate shocks in pregnancy, ICD discharge in pregnancy and ICD shock in pregnancy. Of 1101 publications found, 27 publications were eligible for further analysis (four retrospective trials and 23 case reports). Results: According to physiological changes in pregnancy, resulting in an increase in heart rate and cardiac output, a vulnerability for malignant arrhythmias and device-related complications in ICD carriers might be suspected. While the literature is limited on this issue, maternal complications including arrhythmia burden with following ICD therapies, thromboembolic events and lead complications as well as inappropriate shock therapy have been reported. According to the limited available studies, associated risk seems not to be more frequent than in the general population and depends on the underlying cardiac pathology. Furthermore, worsening of heart failure and related cardiovascular disease have been reported with associated risk of preterm delivery. These observations are exaggerated by restricted applications of diagnostics and treatment due to the risk of fetal harm in this population. Conclusions: Due to limited data on management of ICDs during pregnancy, further scientific investigations are required. Consequently, careful risk assessment with individual risk evaluation and close follow ups with interdisciplinary treatment are recommended in pregnant ICD carriers.