Reduction of sleep-disordered breathing following effective percutaneous mitral valve repair with the MitraClip system

Purpose This study tested the hypothesis that a reduction of pulmonary congestion achieved by a reduction of mitral regurgitation (MR) severity in heart failure (HF) patients is associated with reduced event lengths of sleep-disordered breathing (SDB). Methods We prospectively enrolled 20 consecutive HF patients who underwent MitraClip implantation. Patients underwent cardiorespiratory polygraphic recording prior to and after percutaneous mitral valve repair (PMVR). Beyond routinely established indicators of apneas and hypopneas per hour (respiratory event index), we manually analyzed apnea event lengths. Results MitraClip implantation led to marked reduction of MR severity and a reduction in left atrial pressure. These hemodynamic changes were accompanied by changes in SDB: the subtype of SDB switched from CSA to OSA in 4 patients. Likewise, quantitative indicators of SDB were altered in both forms of SDB with a reduction in circulatory delay (CSA 38 +/- 14 vs. 33 +/- 15 s.; p = 0.002 and OSA 34 +/- 9 vs. 28 +/- 6 s.; p = 0.02) and a corresponding reduction in ventilation lengths in CSA patients (42 +/- 15 vs. 37 +/- 13 s.; p = 0.05). Conclusion A reduction of pulmonary congestion as achieved by a decrease of left atrial pressure through successful MitraClip implantation is associated with a reduction in respiratory event lengths, further pointing towards a relation between SDB and HF.