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Long-term efficacy and safety of phrenic nerve stimulation for the treatment of central sleep apnea.Sleep Oct 2019To evaluate long-term efficacy and safety of phrenic nerve stimulation (PNS) in patients with moderate-to-severe central sleep apnea (CSA) through 3 years of therapy.
STUDY OBJECTIVE
To evaluate long-term efficacy and safety of phrenic nerve stimulation (PNS) in patients with moderate-to-severe central sleep apnea (CSA) through 3 years of therapy.
METHODS
Patients in the remedē System Pivotal Trial were observed every 3 months after implant until US Food and Drug Administration approval. At the time of approval and study closure, all patients completed 24 months of follow-up; 33 patients had not reached the 36-month visit. Sleep metrics (polysomnography) and echocardiographic parameters are reported at baseline, 12, 18, and 24 months, in addition to available 36-month sleep results from polygraphy. Safety was assessed through 36 months; however, analysis focused through 24 months and available 36-month results are provided.
RESULTS
Patients were assessed at 24 (n = 109) and 36 (n = 60) months. Baseline characteristics included mean age 64 years, 91% male, and mean apnea-hypopnea index 47 events per hour. Sleep metrics (apnea-hypopnea index (AHI), central apnea index, arousal index, oxygen desaturation index, rapid eye movement sleep) remained improved through 24 and 36 months with continuous use of PNS therapy. At least 60% of patients in the treatment group achieved at least 50% reduction in AHI through 24 months. Serious adverse events (SAEs) related to the remedē System implant procedure, device, or therapy through 24 months were reported by 10% of patients, no unanticipated adverse device effects or deaths, and all events resolved. No additional related SAEs were reported between 24 and 36 months.
CONCLUSION
These data suggest beneficial effects of long-term PNS in patients with CSA appear to sustain through 36 months with no new safety concerns.
TRIAL REGISTRATION
NCT01816776.
Topics: Aged; Electric Stimulation Therapy; Female; Follow-Up Studies; Humans; Longitudinal Studies; Male; Middle Aged; Phrenic Nerve; Polysomnography; Prospective Studies; Quality of Life; Sleep Apnea, Central; Treatment Outcome
PubMed: 31634407
DOI: 10.1093/sleep/zsz158 -
The Journal of Physiological Sciences :... Mar 2020Respiratory disturbances present in Parkinson's disease (PD) are not well understood. Thus, studies in animal models aimed to link brain dopamine (DA) deficits with...
Respiratory disturbances present in Parkinson's disease (PD) are not well understood. Thus, studies in animal models aimed to link brain dopamine (DA) deficits with respiratory impairment are needed. Adult Wistar rats were lesioned with injection of 6-hydroxydopamine (6-OHDA) into the third cerebral ventricle. Two weeks after hypoxic test was performed in whole-body plethysmography chamber, phrenic (PHR) and hypoglossal (HG) nerve activities were recorded in normoxic and hypoxic conditions in anesthetized, vagotomized, paralyzed and mechanically ventilated rats. The effects of activation and blockade of dopaminergic carotid body receptors were investigated during normoxia in anesthetized spontaneously breathing rats. 6-OHDA injection affected resting respiratory pattern in awake animals: an increase in tidal volume and a decrease in respiratory rate had no effect on minute ventilation. Hypoxia magnified the amplitude and minute activity of the PHR and HG nerve of 6-OHDA rats. The ratio of pre-inspiratory to inspiratory HG burst amplitude was reduced in normoxic breathing. Yet, the ratio of pre-inspiratory time to total time of the respiratory cycle was increased during normoxia. 6-OHDA lesion had no impact on DA and domperidone effects on the respiratory pattern, which indicate that peripheral DA receptors are not affected in this model. Analysis of monoamines confirmed substantial striatal depletion of dopamine, serotonin and noradrenaline (NA) and reduction of NA content in the brainstem. In bilateral 6-OHDA model changes in activity of both nerves: HG (linked with increased apnea episodes) and PHR are present. Demonstrated respiratory effects could be related to specific depletion of DA and NA.
Topics: Adrenergic Agents; Animals; Brain; Disease Models, Animal; Dopamine; Hypoglossal Nerve; Hypoxia; Male; Norepinephrine; Oxidopamine; Parkinson Disease; Parkinson Disease, Secondary; Phrenic Nerve; Rats; Rats, Wistar; Respiration
PubMed: 32160868
DOI: 10.1186/s12576-020-00743-4 -
International Journal of Chronic... 2022This review summarizes the characteristics, assessment methods, and targeted rehabilitation therapies of diaphragm dysfunction in patients with chronic obstructive... (Review)
Review
PURPOSE
This review summarizes the characteristics, assessment methods, and targeted rehabilitation therapies of diaphragm dysfunction in patients with chronic obstructive pulmonary disease (COPD).
METHODS
Extensive literature was searched in PubMed, the Cochrane Library, Web of Science, Chinese National Knowledge Infrastructure Database, Wanfang, and SinoMed.
RESULTS
Under the influence of oxidative stress, inflammation, and other factors, the diaphragm function of patients with COPD changes in mobility, muscle strength, thickness, and thickening. In patients with COPD, diaphragm mobility can be assessed using ultrasound, X-ray fluoroscopy, and magnetic resonance imaging. Diaphragmatic strength can be measured by transdiaphragmatic pressure and maximal inspiratory pressure. Diaphragmatic thickness and thickening can be assessed using ultrasound. Rehabilitation therapies targeting the diaphragm include diaphragmatic breathing, diaphragm-related manual therapy, and phrenic nerve electrical stimulation. Diaphragmatic breathing is safe, simple, and not limited by places. Diaphragmatic manual therapies, which require patient cooperation and one-on-one operation by a professional therapist, are effective. Phrenic nerve electrical stimulation is suitable for patients with severe conditions. These therapies improve the diaphragmatic function, lung function, dyspnea, and exercise capacity of patients with COPD.
CONCLUSION
The diaphragmatic function is commonly assessed in terms of mobility, strength, thickness, and thickening. Diaphragmatic targeted rehabilitation therapies have proven to be efficient, which are recommended to be included in the pulmonary rehabilitation strategy for patients with COPD.
Topics: Diaphragm; Dyspnea; Humans; Phrenic Nerve; Pulmonary Disease, Chronic Obstructive; Ultrasonography
PubMed: 35273448
DOI: 10.2147/COPD.S338583 -
Sleep & Breathing = Schlaf & Atmung Dec 2021Positive airway pressure (PAP) therapy for central sleep apnea (CSA) is often poorly tolerated, ineffective, or contraindicated. Transvenous phrenic nerve stimulation... (Randomized Controlled Trial)
Randomized Controlled Trial
STUDY OBJECTIVE
Positive airway pressure (PAP) therapy for central sleep apnea (CSA) is often poorly tolerated, ineffective, or contraindicated. Transvenous phrenic nerve stimulation (TPNS) offers an alternative, although its impact on previously PAP-treated patients with CSA has not been examined.
METHODS
TPNS responses among PAP-naïve and prior PAP-treated patients from the remedē System Pivotal Trial were assessed. Of 151, 56 (37%) used PAP therapy before enrolling in the trial. Patients were implanted with a TPNS device and randomized to either active or deferred (control) therapy for 6 months before therapy activation. Apnea-hypopnea index (AHI) and patient-reported outcomes (PRO) were assessed at baseline, and 6 and 12 months following active therapy.
RESULTS
Patients had moderate-severe CSA at baseline, which was of greater severity and more symptomatic in the PAP-treated vs. PAP-naïve group (median AHI 52/h vs. 38, central apnea index (CAI) 32/h vs. 18, Epworth Sleepiness Scale 13 vs. 10, fatigue severity scale 5.2 vs. 4.5). Twelve months of TPNS decreased AHI to <20/h and CAI to ≤2/h. Both groups showed reductions in daytime sleepiness and fatigue, improved well-being by patient global assessment, and high therapeutic acceptance with 98% and 94% of PAP-treated and PAP-naïve patients indicating they would undergo the implant again. Stimulation produced discomfort in approximately one-third of patients, yet <5% of prior PAP-treated participants discontinued therapy.
CONCLUSION
Polysomnographic and clinical responses to TPNS were comparable in PAP-naïve and prior PAP-treated CSA patients. TPNS is a viable therapy across a broad spectrum of CSA patients.
TRIAL REGISTRATION
ClinicalTrials.gov Identifier NCT01816776; March 22, 2013.
Topics: Aged; Continuous Positive Airway Pressure; Electric Stimulation Therapy; Female; Humans; Implantable Neurostimulators; Male; Middle Aged; Patient Reported Outcome Measures; Phrenic Nerve; Quality of Life; Sleep Apnea, Central; Sleep Quality
PubMed: 33745107
DOI: 10.1007/s11325-021-02335-x -
Medicina (Kaunas, Lithuania) Sep 2023Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects both the upper and lower motor neurons in the nervous system, causing muscle...
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects both the upper and lower motor neurons in the nervous system, causing muscle weakness and severe disability. The progressive course of the disease reduces the functional capacity of the affected patients, limits daily activities, and leads to complete dependence on caregivers, ultimately resulting in a fatal outcome. Respiratory dysfunction mostly occurs later in the disease and is associated with a worse prognosis. Forty-six participants were included in our study, with 23 patients in the ALS group and 23 individuals in the control group. The ultrasound examination of the phrenic nerve (PN) was performed by two authors using a high-resolution "Philips EPIQ 7" ultrasound machine with a linear 4-18 MHz transducer. Our study revealed that the phrenic nerve is significantly smaller on both sides in ALS patients compared to the control group ( < 0.001). Only one significant study on PN ultrasound in ALS, conducted in Japan, also showed significant results ( < 0.00001). These small studies are particularly promising, as they suggest that ultrasound findings could serve as an additional diagnostic tool for ALS.
Topics: Humans; Amyotrophic Lateral Sclerosis; Phrenic Nerve; Neurodegenerative Diseases; Prognosis; Muscle Weakness
PubMed: 37893463
DOI: 10.3390/medicina59101745 -
Respiratory Physiology & Neurobiology Sep 2022To evaluate the phrenic nerve compound muscle action potential (CMAP) in rats after diabetes mellitus (DM) induction.
PURPOSE
To evaluate the phrenic nerve compound muscle action potential (CMAP) in rats after diabetes mellitus (DM) induction.
METHODS
Twenty DM animals (intravenous streptozotocin, 45 mg.kg) and 25 controls underwent CMAP analysis before and 30, 60 and 90 days after DM induction.
RESULTS
Amplitude (mV) progressively declined in DM group after 30 (Mean difference (MD): -0.915, 95 % Confidence interval (CI) -1.580 to -0.250, p < 0.01), 60 (MD: -1.122, 95 % CI -1.664 to -0.581, p < 0.001) and 90 days (MD: -2.226, 95 % CI -3.059 to -1.393, p < 0.001); as well as the area (mV.ms) after 30 (MD: -3.19, 95 % CI -5.94 to -0.44, p < 0.05), 60 (MD: -3.94, 95 % CI -6.24 to -1.64, p < 0.001) and 90 days (MD: -8.64, 95 % CI -12.08 to -5.21, p < 0.001). Transient differences were observed in latency and duration at 60 days.
CONCLUSIONS
The progressive changes in phrenic nerve CMAP observed during DM suggest a decrement in axonal function rather than substantial demyelination.
Topics: Action Potentials; Animals; Diabetes Mellitus, Experimental; Muscles; Neural Conduction; Phrenic Nerve; Rats; Streptozocin
PubMed: 35654367
DOI: 10.1016/j.resp.2022.103923 -
COPD Aug 2020In patients with moderate-to-severe Chronic Obstructive Pulmonary Disorder (COPD), pulmonary hyperinflation can occur at rest and increase during episodes of...
In patients with moderate-to-severe Chronic Obstructive Pulmonary Disorder (COPD), pulmonary hyperinflation can occur at rest and increase during episodes of exacerbation. Among other mechanical constraints, changes in position and configuration of the diaphragm are also induced by increased end-expiratory lung volume. Both descent and flattening of diaphragm might damage the phrenic nerves by stretching their fibers. The study aimed to investigate the phrenic nerve conduction in COPD patients in stable conditions and during COPD exacerbation. In a group of 11 COPD patients without relevant comorbidities in stable conditions and subsequently in another group of 10 COPD patients during in-hospital COPD exacerbation and recovery, measurements of functional respiratory parameters and assessment of phrenic nerves motor conduction by bilateral electric stimulation were performed concurrently. Significant increase in phrenic nerves latency ( < 0.05), but similar amplitude of motor compound muscle action potential (cMAP) was observed in stable COPD patients vs. matched controls ( < 0.05). However, in COPD patients with resting pulmonary hyperinflation as reliably detected by substantial Inspiratory Capacity reduction (<80% pred.), the mean bilateral latency was longer vs. COPD patients without pulmonary hyperinflation ( < 0.02). During COPD exacerbation, in contrast with mean latency, the mean amplitude of phrenic nerves cMAP improved at discharge when compared with in-hospital admission ( < 0.05). In stable COPD patients the velocity of phrenic nerve conduction was impaired mostly in the presence of pulmonary hyperinflation, while during COPD exacerbation where dynamic pulmonary hyperinflation abruptly occurs, the reversible decrease of cMAP amplitude does suggest a temporary, acute axonal damage of phrenic nerves, potentially contributing to diaphragmatic dysfunction in these circumstances.
Topics: Aged; Aged, 80 and over; Diaphragm; Disease Progression; Female; Humans; Inspiratory Capacity; Lung Volume Measurements; Male; Middle Aged; Neural Conduction; Phrenic Nerve; Pulmonary Disease, Chronic Obstructive; Reaction Time; Recovery of Function; Respiratory Mechanics
PubMed: 32586145
DOI: 10.1080/15412555.2020.1779680 -
Thoracic Surgery Clinics May 2024An elevated diaphragm may be due to eventration or paralysis. Diaphragm elevation is often asymptomatic and found incidentally on imaging. Fluoroscopic testing can be...
An elevated diaphragm may be due to eventration or paralysis. Diaphragm elevation is often asymptomatic and found incidentally on imaging. Fluoroscopic testing can be used to differentiate eventration (no paradoxic motion) from paralysis (paradoxic motion). Regardless of etiology, a diaphragm plication is indicated in all symptomatic patients with an elevated diaphragm. Plication can be approached either from a thoracic or abdominal approach, though most thoracic surgeons perform minimally invasive thoracoscopic plication. The goal of plication is to improve lung volumes and decrease paradoxic elevation of the hemidiaphragm. Diaphragm plication is safe, has excellent outcomes, and is associated with symptom improvement.
Topics: Humans; Diaphragm; Diaphragmatic Eventration; Respiratory Paralysis
PubMed: 38705666
DOI: 10.1016/j.thorsurg.2024.01.006 -
World Neurosurgery May 2022Traumatic brachial plexus injuries are devastating lesions, and neurotization is an usually elected surgical therapy. The phrenic nerve has been harvested as a motor...
BACKGROUND
Traumatic brachial plexus injuries are devastating lesions, and neurotization is an usually elected surgical therapy. The phrenic nerve has been harvested as a motor fibers donor in brachial plexus neurotization, showing great results in terms of motor reinnervation. Unfortunately, these interventions lack solid evidence regarding long-term safety and possible late respiratory function sequelae, raising crescent concerns after the COVID-19 pandemic onset and possibly resulting in reduced propensity to use this technique. The study of the distal anatomy of the phrenic nerves may lead to a better understanding of their branching patterns, and thus the proposition of surgical approaches that better preserve patient respiratory function.
METHODS
Twenty-one phrenic nerves in 10 formalized cadavers were scrutinized. Prediaphragmatic branching patterns were inspected through analysis of the distance between the piercing site of the nerve at the diaphragm and the cardiac structures, number of divisions, and length from the point where the main trunk emits its branches to the diaphragm.
RESULTS
The main trunk of the right phrenic nerve reaches the diaphragm near the inferior vena cava and branches into 3 major divisions. The left phrenic nerve reaches the diaphragm in variable locations near the heart, branching into 2-5 main trunks. Moreover, we noticed a specimen presenting 2 ipsilateral parallel phrenic nerves.
CONCLUSIONS
The right phrenic nerve presented greater consistency concerning insertion site, terminal branching point distance to this muscle, and number of rami than the left phrenic nerve.
Topics: COVID-19; Diaphragm; Humans; Nerve Transfer; Pandemics; Phrenic Nerve
PubMed: 35077891
DOI: 10.1016/j.wneu.2022.01.061 -
Heart and Vessels May 2023Preventing phrenic nerve injury (PNI) during balloon-based ablation is essential. The superior vena cava-right atrial (SVC-RA) junction is located just opposite the...
Comparison of phrenic nerve injury and its effect on the extrapulmonary vein structures with cryoballoon and hot-balloon ablation systems: considering the lesion created on the superior vena cava as a surrogate marker.
Preventing phrenic nerve injury (PNI) during balloon-based ablation is essential. The superior vena cava-right atrial (SVC-RA) junction is located just opposite the balloon position during right superior pulmonary vein (RSPV) ablation, and the phrenic nerve runs nearby on the lateral side. We compared the occurrence of PNI between the two balloon-based ablation systems and also the lesions created at the SVC-RA junction, which were expected to represent the effect on extra-PV structures. Cryoballoon ablation (CBA, n = 110) and hot-balloon ablation (HBA, n = 90) were performed in atrial fibrillation patients. High-density maps of the SVC-RA junction were created in 93 patients (CBA = 53, HBA = 40), and the damaged area (< 1.0 mV) was determined as an "SVC lesion". CBA had a higher occurrence of transient PNI (7.3% vs 1.1%, p = 0.035), but all recovered during the 6-month follow-up. An apparent SVC lesion was documented in 43% of the patients (40/93), and all patients with PNI had this lesion. CBA created a frequent (CBA vs HBA = 55% vs 28%, p = 0.008) and wider (0.8[0.4-1.7] cm vs 0.5[0.3-0.7] cm, p = 0.005) SVC lesion than HBA. A multivariate analysis revealed that the use of a CBA system was a predictive factor of the occurrence of SVC lesions. CBA had a higher occurrence of transient PNI but not a permanent form. Every patient with PNI had lesions on the SVC-RA junction, and CBA revealed more substantial ablation effects at the SVC-RA junction than HBA. This may be caused by the different characteristics of the two balloon-based ablation systems and their balloon positions.
Topics: Humans; Vena Cava, Superior; Phrenic Nerve; Cryosurgery; Atrial Fibrillation; Pulmonary Veins; Biomarkers; Catheter Ablation; Treatment Outcome
PubMed: 36446927
DOI: 10.1007/s00380-022-02210-z