Introduction: Compared to tachyarrhythmias, little information is available regarding familial bradyarrhythmias.
Cases report: Case 1: A 52-year-old woman (proband) was referred because of repeated syncope. At the time of electrophysiological study 5.4sec pause by sinus arrest with chest discomfort was documented. After permanent pacemaker (PPM) implantation, she did not suffer from syncope at all. Case 2: A 27-year-old man (proband’s son) experienced fainting and syncope for few years. He experienced these symptoms especially during bating or hot days. 2 months after implantable loop recorder (ILR) implantation, he suffered from syncope during bathing and he was almost drowned. 10.2sec pause related with sinus arrest was recorded. He did not have any syncope after PPM implantation. Case 3: A 25-year-old woman (proband’s daughter) had repeated fainting and syncope following nausea. Baseline systolic BP was around 90mmHg. Head-up tilt test revealed no obvious abnormality except mild decreasing BP (<10mmHg). Because ILR did not record any ECG abnormalities even during spontaneous fainting, she is treated medically .
Conclusions: Though any genetic abnormalities were not detected in this family, familial neurally mediated syncope is mostly suspected.