Recognition of fetal arrhythmias by echocardiography

Abstract

Fetal arrhythmias were detected in 33/198 high risk pregnancies from 21 weeks to term. Using the two-dimensional echocardiographic image of the fetal heart as a guide, the M-mode beam was directed to define the motion of the ventricular and atrial walls and atrioventricular valve or semilunar valves. Atrial contraction was defined either by the atrial wall motion or from the A-point of the atrioventricular valve. Ventricular contraction was defined by closure of the atrioventricular valve (C-point), the onset of ventricular wall contraction, or from the semilunar valve opening. Ladder diagrams of the sequence of atrial and ventricular activation were constructed to define the temporal sequence of these events. Premature atrial contractions were present in 12. In one fetus this arrhythmia converted into supraventricular tachycardia while in the other 11 fetuses the course was benign. Two fetuses had premature ventricular contractions. Supraventricular tachycardia was noted in five fetuses. One with hydrops at 29 weeks returned to sinus rhythm following maternal administration of procainamide. A second hydropic fetus with paroxysmal atrial tachycardia and hydrops failed to respond to digitalis, propranolol, procainamide, verapamil, or amiodarone, and died shortly after cesarean section. Two mature fetuses had tachycardia close to term and were treated after cesarean section. One fetus with runs of atrial tachycardia died in utero. Three fetuses had complete heart block, two of whom were from mothers with connective tissue diseases. In four fetuses, there was bradycardia of less than 100/minute lasting more than 30 seconds, but these episodes disappeared in 2 minutes.(ABSTRACT TRUNCATED AT 250 WORDS)

Transient Non-Autoimmune Fetal Heart Block

“…Furthermore, bradycardia was observed on two consecutive occasions (at referral and at evaluation at our center) in 3 of the 4 patients. Patient 4 presented with heart block at 16 weeks' GA, PACs are only rarely observed so early during pregnancy Breur/Oudijk/Stoutenbeek/Visser/ Meijboom [11]. Fetal magnetocardiography, a technique that records the magnetic field in a location near the maternal abdomen and in this way reflects the electric activity within the fetal heart, offers beat-to-beat measurements and morphological analysis of the fetal heart beat [12].…”

Fetoscopic Transesophageal Electrocardiography and Stimulation in Fetal Sheep

“…Whereas tachycardia conversion is generally achieved in nonhydropic fetuses, fetuses with supraventricular tachycardia and hydrops respond less well to empirical antiarrhythmic therapy. 1,[21][22][23][24][25][26] Premature delivery of this subgroup of patients results in additional complications. 4,5 Therefore, the mortality in this group has been considerable, 1 and accurate definition of the underlying mechanism by fetal transesophageal electrocardiography and stimulation may be helpful.…”

Atrial Fibrillation in Children

“…Depending on the report, fetal atrial flutter or fibrillation accounts for somewhere between 20-33% of all fetal tachyarrythmias (Azancot-Benistry et al, 1992;Belhassen et al, 1982;Silverman et al, 1985;Simpson et al, 1998)and may be detected on routine obstetrical examination as an irregular or rapid fetal heart rate. In general, any congenital heart disease may predispose to development of atrial fibrillation in this period, but several specific entities are generally considered higher risk.…”

“…Atrial septal defects, ventricular septal defects, atrioventricular canal, Ebstein anomaly, cor triatriatum and any single ventricular anatomy (most prominently hypoplastic left heart) are all felt to be higher than average risk for fetal atrial tachyarrythmia. The most common arrythmia defined in several series is premature atrial contractions, which is most often benign, but has the potential to convert to an atrial tachyarrythmia (Belhassen et al, 1982;Silverman et al, 1985). Detection of fetal arrhythmia is primarily done clinically using ultrasound in most settings, and is well validated in multiple reports.…”