Sleep-disordered breathing and effectiveness of cardiac resynchronization therapy in heart failure patients: gender differences?

Objectives: This study evaluated heart failure (HF) patients who underwent cardiac resynchronization therapy (CRT) and who had device-documented sleep-disordered breathing (SDB). We found gender differences in acute changes in SDB due to CRT impact.

Background: SDB typically occurs in HF patients. However, the role of SDB and its response to CRT in HF patients, as well as the relation with gender are currently not fully researched.

Methods: Among 63 consecutive patients who received CRT with an SDB algorithm, 23 patients documented SDB at one-month cardiac device interrogation and represented our population. We defined a Sleep apnoea Severity SCore(SSSC), and consequently, patients were categorized to have mild, moderate, and severe sleep apnoea syndrome divided into two groups: Group-1: 18 males (78%); Group-2: 5 females (22%). We evaluated the variation of apnoea burden and CRT response based on gender differences.

Results: A significantly higher proportion of patients in the male group were non-responders to CRT at 12-months follow-up (p = 0.076) while in the female population 5/5 patients (100%) were responders to CRT at the same follow-up time (p = 0.021). Among Group-2 subjects, we documented a significant linear decrease in SSSC(p > 0,01) while in Group-1 the CRT effect on SSSC was variable. At 12-months follow-up, the difference in SSSC between the two groups was statistically significant (p < 0.001).

Conclusions: Our study reports a correlation between CRT response and sleep apnoea burden considering gender differences. In particular, HF-women responders to CRT demonstrate a significant linear decrease in sleep apnoea burden determined through a device algorithm, when compared to a similar male population. Further research is needed to confirm these findings.