Diagnosis, clinical features, management, and post-natal follow-up of fetal tachycardias

Abstract

Objective: To evaluate the diagnosis, clinical features, management and post-natal follow-up in consecutive fetuses identified with tachycardia. Methods: We reviewed consecutive fetuses with tachycardia identified in a single tertiary institution between January, 2001, and December, 2008. We considered several options for management, including no treatment but close surveillance, trans-placental antiarrhythmic therapy in fetuses presenting prior to 36 weeks of gestation, and delivery and treatment as a neonate for fetuses presenting after 36 weeks of gestation. Data was gathered by a review of prenatal and postnatal documentation. Results: Among 29 fetuses with tachycardia, 21 had supraventricular tachycardia with 1 to 1 conduction, 4 had atrial flutter, 3 had atrial tachycardia, while the remaining fetus had ventricular tachycardia. Of the group, 8 fetuses (27.6%) were hydropic. Transplacental administration of antiarrhythmic drugs was used in just over half the fetuses, delivery and treatment as a neonate in one-quarter, and no intervention but close surveillance in one-sixth of the case. Twenty-six of 29 fetuses (89.7%) were born alive. Only patients with fetal hydrops suffered mortality, with 37.5% of this group dying, this being statistically significant, with the value of p equal to 0.03, when compared to non-hydropic fetuses. Only 3 patients (11.5%) were receiving antiarrhythmic prophylaxis beyond the first year of life. Conclusion: A significant proportion of fetal tachycardias recognized before 36 weeks of gestation can be treated successfully by transplacental administration of antiarrhythmic drugs. Fetuses presenting after 36 weeks of gestation can be effectively managed postnatally. The long-term prognosis for fetuses diagnosed with tachycardia is excellent, with the abnormal rhythm resolving spontaneously during the first year of life in most of them.

Neonatal atrial flutter: Three cases and review of the literature

“…After 36th gestational week postnatal medications, transesophageal overdrive pacing, or synchronized direct current cardioversion (DCC) might be the choices of treatment. 11 Cardioversion for neonatal AFl is often successful with as little as 0.25-0.5 J/kg with the current biphasic devices. 12 However it is use in neonates has not been approved yet, ibutilide is reported to be effective in some cases of AFl.…”

Rapid control of foetal supraventricular tachycardia with digoxin and flecainide combination treatment

“…In the foetuses who are delivered early, the outcome is often poor, with substantial mortality and morbidity due to inherent problems of prematurity. 12 Therefore, most clinicians would aim to treat the mothers with anti-arrhythmic medication in order to restore sinus rhythm in the foetus. If restoration of sinus rhythm is not achievable, reduction of foetal heart rate to 160 may be targeted to prevent or resolve signs of cardiac failure and to delay delivery of the foetus beyond 34 weeks of gestation or earlier if deemed necessary.…”

“…Uncommonly, some algorithms suggest the wait-and-see approach as long as 1 or 2 weeks before considering a change in the treatment. 1,2,12 Digoxin has been widely used in the treatment of foetal tachycardia as a first-line agent, but results are rather conflicting with varying success rates of 46-62%. 1,2,9,12,16 In case of hydrops, digoxin becomes rather ineffective, with lower success rates of 0-10%.…”

“…The first six foetuses out of 27 were initially treated with either digoxin -in five -or flecainide alone -in one -according to the protocols reported in the literature. 7,8,12 Owing to the fact that there was no change in foetal heart rate after 4-14 days of monotherapy with digoxin or flecainide, in spite of high maternal drug levels, a second anti-arrhythmic medication, either flecainide or digoxin, was later initiated in all six patients. Hence, all 27 patients had received the combination treatment.…”

Importance of Close Follow-Up in the Fetus with Premature Atrial Contractions Accompanied by Atrial Septal Aneurysm: A Case Report

“…Fetal sinus tachycardia is defined as a fetal heart rate not exceeding 210–220 bpm with a well-preserved AV conduction. It is a benign condition not requiring treatment expected to improve spontaneously during the first year of life [10]. In our case, however, fetal bradycardia followed by incessant fetal sinus tachycardia caused gradually increasing tricuspid valve insufficiency and ventricular dysfunction and necessitated early delivery.…”