Pericardial mechanoreceptors with phrenic afferents

1993 ◽  
Vol 264 (6) ◽  
pp. H1836-H1846 ◽  
Author(s):  
D. R. Kostreva ◽  
S. P. Pontus
Keyword(s):  
Phrenic Nerve ◽  
Cardiac Rhythm ◽  
Afferent Activity ◽  
Fibrous Layer ◽  
Anesthetized Dogs ◽  
Anatomic Distribution ◽  
Phrenic Nerves ◽  
The Right

Pericardial mechanoreceptors with afferents in the phrenic nerves were studied in anesthetized dogs. The specific aims determined 1) if pericardial receptors with phrenic afferents exist in the dog; 2) the stimuli needed to activate these receptors; 3) the anatomic distribution of these pericardial receptors; and 4) which pericardial layer contains the receptors. Afferent activity was recorded from the phrenic nerves while the pericardium was probed. In 15 of 18 animals, pericardial receptors were found on the right side. In 12 of 18 animals pericardial receptors were located on the left side. Most of the mechanoreceptors were found in a band that paralleled the pericardiophrenic attachment, in the fibrous layer of the pericardium, overlying the atria and atrioventricular grooves. Some receptors had a cardiac rhythm, whereas others were stimulated by the inflating lung. None of the receptors were chemosensitive to capsaicin, bradykinin, or saline. This study is the first to demonstrate that the pericardium of the dog contains mechanosensitive receptors which are innervated by the phrenic nerve.

P2625Pathophysiology of diaphragm involvement in systolic heart failure: insights from diaphragm ultrasound and phrenic nerve stimulation studies

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
J Spiesshoefer ◽  
I T Tuleta ◽  
A G Giannoni ◽  
M B Boentert
Keyword(s):  
Heart Failure ◽  
Phrenic Nerve ◽  
Systolic Heart Failure ◽  
Exercise Intolerance ◽  
Design Data ◽  
Diaphragm Function ◽  
Phrenic Nerves ◽  
And Gender ◽  
The Right ◽  
Conductive Properties

Abstract Background Diaphragm ultrasound allows for assessment of both diaphragm excursion and thickness. Cervical and cortical magnetic stimulation (CEMS and COMS) with recording of the diaphragmatic compound motor action potential (CMAP) is diagnostically useful to evaluate the conductive properties of the inspiratory pathway. Systolic heart failure (HF) is characterized by a loss of systolic pump function. Diaphragm weakness in HF has been reported to potentially contribute to exercise intolerance Methods 14 patients with systolic HF (11 men, 3 women; 64±12 years, NYHA 2±0.9, LVEF 36.1±5.6%) and 12 healthy controls matched for age and gender (4 men, 8 women; 56±8 years) underwent spirometric lung function testing and assessment of diaphragm excursion (during tidal breathing, TB, voluntary sniff, VS and deep breathing, DB) and thickness of the right hemidiaphragm by ultrasound. COMS and CEMS of the phrenic nerves with simultaneous bilateral recording of the diaphragm CMAP using surface electrodes was performed in 9 patients. Results Compared to controls, HF patients showed reduced forced vital capacity (75.46±18.05% vs. 107.62±17.13%, p<0.05). Diaphragm excursion amplitude was significantly reduced in HF patients (4.29±1.35 cm vs. 7.34±2.10 cm, p<0.05). Diaphragm contractility was impaired too, as reflected by the diaphragm thickening ratio (DTR; 2.01±0.46 vs. 2.53±0.74, p<0.05). Diaphragm CMAP following COMS and CEMS of the phrenic nerves revealed normal latencies in HF patients compared to controls (COMS Latency; 19.05±2.37 msec vs. 18.97±3.59 msec, p= n. s.). Conclusions Diaphragm involvement in systolic HF is reflected by reduced FVC and impaired ultrasound parameters of diaphragm function. Diaphragmatic pathology is likely to be myopathic because magnetic phrenic nerve conduction studies show no abnormalities. Diaphragm ultrasound may be useful as a diagnostic tool for assessment of diaphragm function in systolic HF. Acknowledgement/Funding This study was supported by Sanofi-Genzyme, Neu-Isenburg, Germany. The funders had no role in study design, data collection and analysis, preparation.

Phrenic nerve conduction times and twitch pressures of the human diaphragm

1985 ◽  
Vol 58 (5) ◽  
pp. 1496-1504 ◽  
Author(s):  
D. K. McKenzie ◽  
S. C. Gandevia
Keyword(s):  
Phrenic Nerve ◽  
Simultaneous Recording ◽  
Emg Activity ◽  
Conduction Time ◽  
Transdiaphragmatic Pressure ◽  
Surface Electrodes ◽  
Midclavicular Line ◽  
Phrenic Nerves ◽  
The Mean ◽  
The Right

A multilumen catheter was modified to allow simultaneous recording of transdiaphragmatic pressure (Pdi) and the electromyographic (EMG) activity of the diaphragm. The catheter was used in 20 healthy males to measure the conduction time of the phrenic nerves and the twitch pressure of each hemidiaphragm during single supramaximal shocks delivered to the phrenic nerve in the neck. Diaphragmatic EMG was also recorded with surface electrodes at various sites on the chest wall. The mean conduction time to the crural fibers was 6.82 +/- 0.64 ms on the right and 7.93 +/- 0.85 ms on the left, whereas that to the costal fibers adjacent to the midclavicular line was 7.68 +/- 0.56 ms on the right and 7.92 +/- 0.92 ms on the left. Significant correlations were found between the conduction time of each phrenic nerve and the height and the age of the subjects. Conduction times measured at different EMG recording sites varied by as much as 2 ms. This variability, and that of previously reported values for phrenic conduction time, may be largely accounted for by differences in the conduction distances that were measured to each site in three cadavers. The evoked change in Pdi had a mean rise time of 92 ms and an amplitude of approximately 10 cmH2O.

Asymmetrical action of the canine diaphragm after single-lung inflation

2011 ◽  
Vol 110 (6) ◽  
pp. 1519-1525 ◽  
Author(s):  
André De Troyer ◽  
Dimitri Leduc ◽  
Pierre Alain Gevenois ◽  
Matteo Cappello
Keyword(s):  
Radius Of Curvature ◽  
Lung Inflation ◽  
Endotracheal Tubes ◽  
Computed Tomographic ◽  
Airway Opening ◽  
Anesthetized Dogs ◽  
Radiopaque Markers ◽  
Phrenic Nerves ◽  
The Right ◽  
Phrenic Stimulation

Single-lung transplantation (SLT) in patients with emphysema leads to a cranial displacement of the diaphragm on the transplanted side and a shift of the mediastinum toward the transplanted lung. The objective of the present study was to assess the effect of unilateral lung inflation on the mechanics of the diaphragm. Two endotracheal tubes were inserted in the two main stem bronchi of six anesthetized dogs, and radiopaque markers were attached along muscle fibers in the midcostal region of the two halves of the diaphragm. The animals were then placed in a computed tomographic scanner, the left or the right lung was passively inflated, and the phrenic nerves were stimulated while the two endobronchial tubes were occluded. As lung volume increased, the fall in airway opening pressure (ΔPao) in the inflated lung during stimulation decreased markedly, whereas ΔPao in the noninflated lung decreased only moderately ( P < 0.001). Also, the two hemidiaphragms shortened both during relaxation and during phrenic stimulation, but the ipsilateral hemidiaphragm was consistently shorter than the contralateral hemidiaphragm. In addition, the radius of curvature of the ipsilateral hemidiaphragm during stimulation increased, whereas the radius of the contralateral hemidiaphragm remained unchanged. These observations indicate that 1) in the presence of unilateral lung inflation, the respiratory action of the diaphragm is asymmetric; and 2) this asymmetry is primarily determined by the differential effect of inflation on the length and curvature of the two halves of the muscle. These observations also imply that in patients with emphysema, SLT improves the action of the diaphragm on the transplanted side.

scholarly journals Reinnervation of the diaphragm by the inferior laryngeal nerve to the phrenic nerve in ventilator-dependent tetraplegic patients with C3-5 damage

2017 ◽  
Vol 3 (4) ◽  
pp. 00052-2017 ◽  
Author(s):  
Eric Verin ◽  
Capucine Morelot-Panzini ◽  
Jesus Gonzalez-Bermejo ◽  
Benoit Veber ◽  
Brigitte Perrouin Verbe ◽  
...  
Keyword(s):  
Phrenic Nerve ◽  
Laryngeal Nerve ◽  
Inferior Laryngeal Nerve ◽  
Laryngeal Reinnervation ◽  
Laryngeal Disease ◽  
Cervical Approach ◽  
Phrenic Nerves ◽  
The Right ◽  
High Level ◽  
Automatic Ventilation

The aim of this study was to evaluate the feasibility of unilateral diaphragmatic reinnervation in humans by the inferior laryngeal nerve. This pilot study included chronically ventilated tetraplegic patients with destruction of phrenic nerve motoneurons.Five patients were included. They all had a high level of tetraplegia, with phrenic nerve motor neuron destruction. They were highly dependent on ventilation, without any possibility of weaning. They did not have other chronic pathologies, especially laryngeal disease. They all had diaphragmatic explorations to diagnose the destruction of the motoneurons of the phrenic nerves and nasoendoscopy to be sure that they did not have laryngeal or pharyngeal disease. Then, surgical anastomosis of the right phrenic nerve was performed with the inferior laryngeal nerve, by a cervical approach. A laryngeal reinnervation was performed at the same time, using the ansa hypoglossi.One patient was excluded because of a functional phrenic nerve and one patient died 6 months after the surgery of a cardiac arrest. The remaining three patients were evaluated after the anastomosis every 6 months. They did not present any swallowing or vocal alterations. In these three patients, the diaphragmatic explorations showed that there was a recovery of the diaphragmatic electromyogram of the right and left hemidiaphragms after 1 year. Two patients had surgical diaphragmatic explorations for diaphragmatic pacing 18–24 months after the reinnervation with excellent results. At 36 months, none of the patients could restore their automatic ventilation.In conclusion, this study demonstrated that diaphragmatic reinnervation by the inferior laryngeal nerve is effective, without any vocal or swallowing complications.

Control of breathing in anesthetized dogs by a left-heart baroreflex

1986 ◽  
Vol 61 (6) ◽  
pp. 2095-2101 ◽  
Author(s):  
T. C. Lloyd
Keyword(s):  
Pulmonary Veins ◽  
Vagal Afferents ◽  
Low Flow ◽  
Base Line ◽  
Left Heart ◽  
Breathing Frequency ◽  
Autonomic Ganglion ◽  
Anesthetized Dogs ◽  
The Right ◽  
Vagal Cooling

Anesthetized open-chest dogs on cardiopulmonary bypass were used to test the hypothesis that breathing reflexly responds to distension of the left-heart chambers. Bypass perfusion withdrew systemic flow from the right atrium and returned it to the aorta after gas exchange. Ventricles were fibrillated. The left heart was isolated by tying all pulmonary veins, and it was perfused separately at low flow admitted through one pulmonary vein and withdrawn from the ventricle. Left-heart pressure was intermittently raised abruptly from a nominal base line of 0 by partial occlusion of outflow. Pressures from approximately 10 to 50 cmH2O caused proportional increases in breathing frequency and decreases in expiratory and inspiratory times. Changes occurred immediately, reached a plateau within approximately 20 s, and were sustained for periods of observation as long as 3 min. Recovery to base line followed stimulus removal. Vagal cooling to 8 degrees C prevented responses, but autonomic ganglion blockade with hexamethonium had no effect. I conclude that breathing may be stimulated by left-heart distension and that this is mediated by large myelinated vagal afferents.

Evaluation of β-Adrenerglc Blocking Agents in Presence of Adrenergic Tone

1972 ◽  
Vol 50 (5) ◽  
pp. 381-388
Author(s):  
Victor Elharrar ◽  
Reginald A. Nadeau
Keyword(s):  
Dose Response ◽  
Sinus Node ◽  
Stellate Ganglion ◽  
Sodium Pentobarbital ◽  
Response Curves ◽  
Chronotropic Response ◽  
Blocking Agents ◽  
Sinus Node Artery ◽  
Anesthetized Dogs ◽  
The Right

The importance of the level of adrenergic tone in the determination of the dose–response curve to noradrenaline (NA) and in the evaluation of β-adrenergic blocking agents was studied in open-chest sodium pentobarbital anesthetized dogs by injecting drugs directly into the sinus node artery. Changes in the level of adrenergic tone by stimulating the right stellate ganglion resulted in variation of the observed chronotropic response to NA and of its ED50. The chronotropic responses were corrected by taking into account the underlying adrenergic tone. The negative chronotropic effect of dl-propranolol (1 and 10 μg) appeared to be related to its β-blocking properties and not to its quinidine-like effects as shown by the lack of effect of d-propranolol injected at the same doses. The magnitude of the negative chronotropic effects of 10 μg of propranolol and 100 μg of practolol, oxprenolol, and sotalol was shown to be related to the initial heart rate and consequently to the level of adrenergic tone. The comparison of these four β-blocking agents was carried out on corrected dose-response curves to NA. Their relative potencies were found to be: propranolol > oxprenolol > practolol > sotalol, corresponding to ratios of 1, [Formula: see text], [Formula: see text], and [Formula: see text]

Low vulnerability of the right phrenic nerve to electroporation ablation

Heart Rhythm ◽  
2015 ◽  
Vol 12 (8) ◽  
pp. 1838-1844 ◽  
Author(s):  
Vincent J.H.M. van Driel ◽  
Kars Neven ◽  
Harry van Wessel ◽  
Aryan Vink ◽  
Pieter A.F.M. Doevendans ◽  
...  
Keyword(s):  
Phrenic Nerve ◽  
The Right

Diaphragmatic flutter

2018 ◽  
Vol 18 (3) ◽  
pp. 224-226 ◽  
Author(s):  
Dean Walton ◽  
Michael Bonello ◽  
Malcolm Steiger
Keyword(s):  
Respiratory Distress ◽  
Medical Treatment ◽  
Abdominal Wall ◽  
Phrenic Nerve ◽  
High Frequency ◽  
Rare Disorder ◽  
Nerve Crush ◽  
Irregular Variable ◽  
The Right ◽  
High Index Of Suspicion

A 78-year-old woman presented with involuntary movements of her abdomen, which started after a right hemispheric stroke. She had irregular, variable, hyperkinetic predominantly right-sided abdominal wall movements. MR scan of brain confirmed a recent infarct in the right occipitotemporal lobe and the right cerebellum. Diaphragmatic fluoroscopy confirmed high-frequency flutter as the cause of her abdominal movements and confirmed the diagnosis of van Leeuwenhoek’s disease. Anthonie van Leeuwenhoek first described this condition in 1723 and had the condition himself. He was a Dutch businessman who is often acknowledged as the first microscopist and microbiologist. He disagreed with his physician who attributed his ailment as being of cardiac origin. Diaphragmatic flutter is a rare disorder that requires a high index of suspicion with symptoms including abnormal abdominal wall movements, dyspnoea and respiratory distress. Despite medical treatment, the patient was still highly symptomatic, so she is currently being considered for a phrenic nerve crush.

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