Prenatal diagnosis of sustained bradycardia with 1 : 1 atrioventricular conduction

Abstract

Objectives

Fetal arrhythmias: Natural history and management

“…Although, in extrasystoles and tachyarrhythmias, several therapeutic approaches have been proposed with good chances of success, bradyarrhythmias (i.e., bradycardia and complete heart block) have a worse prognosis, also because of the frequent association with cardiac malformations (Maeno et al 2003;Crawford et al 1985;Wladimiroff et al 1998). In our study, we confirm this association because 66% of our cases had cardiac malformations and 16% had other structural anomalies.…”

Guidelines for fetal echocardiography

“…Occasionally, however, sustained bradycardia is identified when the general condition of the fetus is poor . Although rare, cases of sinus bradycardia and sinus node dysfunction manifesting as arrhythmia have been reported …”

“…37 Although rare, cases of sinus bradycardia and sinus node dysfunction manifesting as arrhythmia have been reported. 39,43…”

Fetal cardiac arrhythmia detection and in utero therapy

“…While mild cases of fetal bradycardia were initially believed by many obstetricians to be benign, links have been identified between uncharacterized fetal bradycardia and long QT syndrome,8,18 SSA/Ro or SSB/La antibody isoimmunization,19 noncompaction syndrome,20 and other life-threatening diseases 21,22. Fetal sinus bradycardia and low atrial bradycardia usually demonstrate heart-rate reactivity even in the presence of serious underlying conditions (Supplementary Figure 1); however, this reactivity may be blunted due to a reduction in autonomic influences.…”