Haemodynamic assessment of fetal heart arrhythmias

Abstract

Summary. The effects of fetal heart arrhythmias were examined serially in two pregnancies by three non‐invasive methods: fetal ECG, fetal phonocardiography and ultrasonic measurement of fetal blood flow. In a case of supraventricular arrhythmia, there was evidence suggesting that the stroke volume varied with ventricular filling according to the Frank ‐ Starling law. In a case of total atrioventricular block the mean blood flow in the fetal descending aorta and in the umbilical vein was within the normal range. Blood flow velocity in the inferior vena cava of the fetus reflected atrial contractions. In the phonocardiogram, a phenomenon similar to‘bruit de canon’ was found. Both pregnancies had good outcomes and subsequent development of the infants was normal except for the persisting dysrhythmias. The two cases exemplify how fetal heart function can be assessed in utero.

Reference values for fetal tissue velocity imaging and a new approach to evaluate fetal myocardial function

“…We could also confirm the gestational increase in fetal myocardial velocities despite a maturational fall in fetal heart rate [7], and the increase of the e’/a’ ratio, corresponding to a redistribution from A-wave towards E-wave dominance with gestational age. The higher ventricular filling velocities confirming the active Frank-Starling mechanism in the fetal heart [7], which is particularly apparent during fetal arrhythmias [21]. The maturational rate of s’ and e’ was higher in the right ventricular free wall compared to the left ventricular free wall and septum, implying that the differential loading of the ventricles does influence the measures of myocardial maturation, unlike Gardiner et al previously suggested [7].…”

Circulatory effects of fetal cardiac arrhythmias

“…Technical developments in ultrasound technique have made it possible to examine noninvasively cardiac morphology [I] and function [7] in utero. Introduction of the pulsed Doppler technique into fetal studies has further improved hemodynamic evaluation [8,19,22].…”

Evaluation of fetal heart rate artifacts, hemodynamics and digoxin treatment in fetal tachyarrhythmia by Doppler measurement of fetal blood flow — case report of a pre-excitation syndrome

“…Serial pulsed Doppler measurements of fetal aortic blood flow [3,9,10] were performed at 30, 32, 33, 35 and 36 weeks of gestation. Thus imminent fetal heart failure was recognized after discontinued medication and before pericardial effusion occured.…”

“…In this case, pre-excitation with bi-or trigeminal pulse caused severe tachycardia, but on the fetal monitor appeared a "normal" heart rate tracing (figure 2); or during the preceding and intrapartum periods of bi-and trigeminal pulse FHR was numerically normal, but a severe bradycardia was recorded (figures 1, and 4). New monitoring developments and Doppler measurement of fetal blood flow may be of help to verify fetal arrthythmia and to quantify their hemodynamic implications [9,10]. An immiment heart failure can be detected before signs of fetal hydrops occur and the therapeutic effect of medication can be monitored by serial measurements of fetal blood flow [11].…”