Arrhythmia and structural abnormalities of the fetal heart.

Abstract

suMMARY Thirty fetuses with cardiac arrythmias were referred for ultrasonography. This included cross sectional and M mode echocardiography and pulsed Doppler analysis of the fetal heart. Three types of arrhythmias were observed: ectopic beats, tachyarrhythmias, and bradycardia. Ectopic beats were associated with cardiac structural abnormalities in two cases, resulting in fetal death in one. Tachycardia was not associated with structural defect, but death from cardiac failure occurred in one patient. Transplacental treatment for tachyarrhythmia was not successful in our experience. In the group with bradycardia four cases had congenital cardiac abnormalities and the mortality rate was 50%.When a fetal cardiac arrhythmia has been established careful structural and rhythm analysis is of vital importance in facilitating prognosis, planning of time and mode of delivery, and monitoring of transplacental treatment where indicated.

Intrauterine therapy of fetal tachyarrhythmias: Intraperitoneal administration of antiarrhythmic drugs to the fetus in fetal tachyarrhythmias with severe hydrops fetalis

“…On the one hand, when the latter antiarrhythmic agents are used, undesirable effects in the fetus may occur, particularly with already existing cardiac insufficiency due to the negative inotropic effects of some of these antiarrhythmic agents. It is still relatively unclear whether and to what extent these drugs cross the placenta [1,2,5,11,12,13].…”

“…If there are contraindications to immediate delivery, such as fetal immaturity, transplacental therapy of the fetus can be achieved by administering antiarrhythmic agents that can cross the placenta to the mother. This has proven to be successful in a number of cases [1,2,9,11,13].…”

Fetal cardiac structure and function as studied by ultrasound

“…Increasing attention has been paid to the prenatal diagnosis of fetal congenital heart disease and cardiac dysrhythmias by means of two-dimensional real-time ultrasound (Allan et al, 1981;Filkins et al, 1981 ;McCallum et al, 1981;Stewart et al, 1983a, b) and Mmode recordings (Kleinman et al, 1980;Stewart et al , 1983b;Wladimiroff et al, 1981). The indications in our ultrasonic unit for structural analysis of the fetal heart are listed in Table I.…”

Prenatal Ultrasound May Predict Fetal Response to Therapy in Non-Hydropic Fetuses with Supraventricular Tachycardia

“…Conversion to sinus rhythm may occur spontaneously. This has been documented in several case reports [8,9] and in a prospective study of 9 non-hydropic fetuses with SVT (7 intermittent, 2 sustained), 8 of whom had spontaneous resolution of SVT within 6 days [10]. However, fetal drug treatment via the mother is usually advocated, mainly to prevent the occurrence of secondary hydrops [1].…”