AIMS: Brugada syndrome is characterized by typical ECG features, ventricular 
arrhythmias and sudden cardiac death (SCD), more frequent during nighttime. 
Autonomic cardiovascular control has been implicated in triggering the 
ventricular arrhythmias. Sleep-disordered breathing (SDB) elicits marked 
autonomic changes during sleep and is also associated with an increased risk of 
nighttime SCD. Brugada patients may have a higher likelihood of SDB compared to 
controls. However, no data are available on cardiac autonomic control in Brugada 
patients, particularly with regard to the comorbidity of SDB.
METHODS: We evaluated autonomic cardiovascular control in Brugada patients with 
SDB (BRU-SDB, n=9), without SDB (BRU, n=9), in controls (CON, n=8) and in 
non-Brugada patients with SDB (n=6), during wakefulness and sleep (N2, N3 and 
REM). Linear spectral and entropy-derived measures of heart rate variability 
(HRV) were performed during apnea-free stable breathing epochs.
RESULTS: Total HRV was attenuated in BRU-SDB compared to CON and BRU. During N2 
and REM, in BRU-SDB patients sympathetic modulation decreased compared to BRU 
and CON, while during REM, they showed an increased parasympathetic modulation, 
compared to the other two groups. BRU-SDB and SDB were similar in terms of 
spectral components. Entropy-derived indices showed preserved dynamic changes in 
Brugada patients compared to controls through the different sleep stages.
CONCLUSION: Brugada syndrome per se does not appear associated with an altered 
autonomic cardiovascular control during wakefulness and sleep. The comorbidity 
with SDB may contribute to disrupted autonomic cardiovascular regulation during 
sleep, possibly predisposing to the increased likelihood of sleep-related 
ventricular tachyarrhythmias and SCD.