P6320Unilateral phrenic nerve stimulation improves functional capabilities in heart failure patients

Abstract

Abstract Introduction Central sleep apnea is highly common in heart failure (HF) patients and often appears as Cheyne-Stokes-respiration (CSR). Presence of CSR in HF has been clearly shown to connote worse prognosis and HF patients with CSR experience increased mortality. Since widely used adaptive servoventilation is now contraindicated in HF with reduced ejection fraction alternative approaches for CSR treatment are needed. Unilateral phrenic nerve stimulation (PNS) is a novel technique to treat CSR and has recently been demonstrated to be safe and effective in HF patients, resulting in its market approval. While PNS has been shown to sufficiently treat CSR nothing is known in regard to functional characteristics in PNS treated HF patients. Therefore, this study investigated standardized six-minute walk test (6MWT) before and during PNS treatment in HF patients assessing functional impact of PNS on HF. Methods We prospectively enrolled 25 HF patients that have been implanted with novel PNS, mean age 67.05±11.22 years, 88% male, showing effective PNS CSR treatment. Adjacent to determine PNS effectiveness on CSR treatment standardized 6MWT was conducted before, at 6 months and at 12 months after PNS implantation. Results 25 (100%) patients had CSR, introduced PNS significantly suppressed respiratory events from 118.33±96.35 before to 34.65±51.41 after PNS therapy onset (p=0.001). Regarding functional improvements 6MWT improved from initial 369.5±163.56 meters before PNS implantation to 410±169.71 meters after 12 months. Hereby, total walking distance increased by 49.5% ± 100.8% (p=0.035). Conclusion PNS treatment is not only a novel technique to allow CSR treatment in HF, but for the first time, we provide comprehensible data illustrating functional improvements in HF in 6MWT, implying significant enhancements in daily physical capability of HF CSR patients treated with PN.