The effects of nifedipine and ivabradine on the functionality of the early rat embryonic heart. Are these drugs a risk in early human pregnancy?

Contemporary Management of Cardiomyopathy and Heart Failure in Pregnancy

Cardiovascular disease is the primary cause of pregnancy-related mortality and morbidity in the United States, and maternal mortality has increased over the last decade. Pregnancy and the postpartum period are associated with significant vascular, metabolic, and physiologic adaptations that can unmask new heart failure or exacerbate heart failure symptoms in women with known underlying cardiomyopathy. There are unique management considerations for heart failure in women throughout pregnancy, and it is imperative that clinicians caring for pregnant women understand these important principles. Early involvement of multidisciplinary cardio-obstetrics teams is key to optimizing maternal and fetal outcomes. In this review, we discuss the unique challenges and opportunities in the diagnosis of heart failure in pregnancy, management principles along the continuum of pregnancy, and the safety of heart failure therapies during and after pregnancy.

Ivabradine use in pregnant women-treatment indications and pregnancy outcome: an evaluation of the German Embryotox database

Purpose

Ivabradine has been approved for the treatment of chronic heart failure and chronic stable angina pectoris in Europe. Based on adverse outcomes of reproductive animal studies and the lack of human data, ivabradine is considered contraindicated during pregnancy. The aim of this observational study is to analyse ivabradine use before and during pregnancy.

Methods

We evaluated all ivabradine-related requests to the German Embryotox Institute from 2007 to 2019. Exposed pregnancies were analysed as to their outcome.

Results

Off-label use for supraventricular tachycardia was frequent in women of childbearing age. Of 38 prospectively ascertained pregnancies with ivabradine exposure and completed follow-up, 32 resulted in live births, 3 in spontaneous abortions, and 3 were electively terminated. One neonate presented with major birth defects (atrial septal defect and cleft palate). In 33/38 patients, ivabradine was discontinued after confirmation of pregnancy without cardiac deterioration and 5/38 women continued ivabradine throughout pregnancy. In addition, there were 3 retrospectively reported pregnancies including one major birth defect (tracheal atresia).

Conclusion

This case series represents the largest cohort of ivabradine-exposed pregnancies, published so far. According to our findings, ivabradine appears not to be a major teratogen. However, established drugs of choice with strong evidence of low risk for the unborn should be preferred in women planning pregnancy. After inadvertent exposure during pregnancy or lack of treatment alternatives, fetal ultrasound for structural anomalies and growth restriction is recommended. In addition, close monitoring is necessary in pregnant women with supraventricular arrhythmias or cardiac disease.

Maternal focal atrial tachycardia during pregnancy: A systematic review

INTRODUCTION

The presentation and optimal management of maternal focal atrial tachycardia (AT) during pregnancy are unknown. The objective of this study is to conduct a comprehensive summary of the existing evidence.

METHODS AND RESULTS

A systematic review of all reported cases of maternal focal AT during pregnancy was performed. The primary search queried PubMed using the MeSH terms "supraventricular tachycardia" and "pregnancy." A stepwise ancillary search included article bibliographies, citations listed by the Google internet search engine, and PubMed using the MeSH terms "atrial tachycardia" and "pregnancy." In total, 28 citations that described 32 patients were retrieved. A case from our institution was added. Detailed information was available for 30 patients. Clinical characteristics at presentation included a mean ± standard deviation of 28.3 ± 5.7 years for maternal age and 24.6 ± 7.7 weeks for gestation age. Suspected tachycardia-induced cardiomyopathy was present in 20 of 30 (67%) patients and left ventricular ejection fraction improved in 15 of 15 (100%) patients with follow-up measurements. Medication failure was common. Focal AT resolved spontaneously after delivery in eight of nine (89%) patients treated with only medications. Automaticity was suggested by discrete electrograms at sites of origin and lack of reported inducibility and termination with programmed stimulation in all patients who underwent electrophysiology studies. There were nine cases of successful catheter ablation with zero fluoroscopy since 2010.

CONCLUSIONS

Automaticity is the dominant mechanism for patients with maternal focal AT during pregnancy. Catheter ablation with zero fluoroscopy is an emerging therapy for medically refractory cases.

Pharmacology of Ivabradine and the Effect on Chronic Heart Failure

Chronic Heart Failure (CHF) is a complex clinical syndrome with a high incidence worldwide. Although various types of pharmacological and device therapies are available for CHF, the prognosis is not ideal, for which, the control of increased Heart Rate (HR) is critical. Recently, a bradycardic agent, ivabradine, is found to reduce HR by inhibiting the funny current (If). The underlying mechanism states that ivabradine can enter the Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels and bind to the intracellular side, subsequently inhibiting the If. This phenomenon can prolong the slow spontaneous phase in the diastolic depolarization, and thus, reduce HR. The clinical trials demonstrated the significant effects of the drug on reducing HR and improving the symptoms of CHF with fewer adverse effects. This review primarily introduces the chemical features and pharmacological characteristics of ivabradine and the mechanism of treating CHF. Also, some expected therapeutic effects on different diseases were also concluded. However, ivabradine, as a typical If channel inhibitor, necessitates additional research to verify its pharmacological functions.