scholarly journals Pulsed Field Ablation Using a Lattice Electrode for Focal Energy Delivery

2020 ◽  
Vol 13 (6) ◽  
Author(s):  
Hagai Yavin ◽  
Ayelet Shapira-Daniels ◽  
Michael Barkagan ◽  
Jakub Sroubek ◽  
David Shim ◽  
...  
Keyword(s):  
Phrenic Nerve ◽  
Histological Analysis ◽  
Esophageal Injury ◽  
Acute Effects ◽  
Histological Changes ◽  
Pulsed Field ◽  
Esophageal Lumen ◽  
Energy Delivery ◽  
Focal Ablation ◽  
The Right

Background: Pulsed field ablation (PFA) is a nonthermal energy that may provide safety advantages over radiofrequency ablation (RFA). One-shot PFA catheters have been developed for pulmonary vein isolation, but they do not permit flexible lesion sets. This study investigated a novel lattice-tip catheter designed for focal RFA or PFA ablation. Methods: The effects of PFA (biphasic, 24 amperes) were investigated in 25 swine using a lattice-tip catheter and system (Affera Inc). Step 1 (n=14) examined the feasibility to create atrial line of block and described its acute effects on the phrenic nerve and esophagus. Step 2 (n=7) examined the subacute effects of PFA on block durability, phrenic nerve, and esophagus ≥2 weeks. Step 3 compared the effects of PFA and RFA on the esophagus using a mechanical deviation model approximating the esophagus to the right atrium (n=4) and by direct ablation within its lumen (n=4). The effects of endocardial PFA and RFA on the phrenic nerve were also compared (n=10). Histological analysis was performed. Results: PFA produced acute block in 100% of lines, achieved with 2.1 (1.3–3.2) applications/cm line. Histological analysis following (35 [18–37]) days showed 100% transmurality (thickness range 0.4–3.4 mm) with a lesion width of 19.4 (10.9–27.4 mm). PFA selectively affected cardiomyocytes but spared blood vessels and nervous tissue. PFA applied from the posterior atria (23 [21–25] applications) to the approximated esophagus (6 [4.5–14] mm) produced transmural lesions without esophageal injury. PFA (16.5 [15–18] applications) applied inside the esophageal lumen produced mild edema compared with RFA (13 [12–14] applications) which produced epithelial ulcerations. PFA resulted in no or transient stunning of the phrenic nerve (<5 minutes) without histological changes while RFA produced paralysis. Conclusions: PFA using a lattice-tip ablation catheter for focal ablation produced durable atrial lesions and showed lower vulnerability to esophageal or phrenic nerve damage compared with RFA.

Acute detection of optical tissue changes in real-time during pulsed field ablation (PFA)

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
K.L Hong ◽  
O Amirana ◽  
T Ransbury ◽  
B Glover
Keyword(s):  
Real Time ◽  
Right Atrium ◽  
Optical Mapping ◽  
Energy Levels ◽  
Optical Signal ◽  
Lesion Formation ◽  
Pulsed Field ◽  
Tissue Changes ◽  
Rf Energy ◽  
The Right

Abstract Background It has been established in previous animal and human studies that it is possible to assess lesion formation in real-time using optical means during the application of radiofrequency (RF) energy in cardiac ablation procedures. The optical interrogation was accomplished using a novel catheter and instrument system whereby the catheter has embedded optical fibers that transmit and receive light from the instrument. Purpose The aim of this study was to see if there are similar indications of lesion formation, detected by the same optical means, during the application of pulsed field ablation (PFA) energy to cause lesions through electroporation. Methods A series of 3 anesthetized pigs underwent PFA in the right atrium. An 8-electrode circular catheter was placed high in the right atrium, near the superior vena cava, to simulate pulmonary vein isolation as part of an AF ablation procedure. The optical catheter was placed adjacent to the circular catheter between stimulation electrode pairs. A bolus of adenosine was administered to create a window of asystole to avoid stimulation on the T-wave. Bipolar PFA was delivered immediately post drug infusion and the optical signature from the catheter was recorded and displayed in real-time. Electrograms were recorded and the mapping of the lesion was performed with the optical catheter at the following time intervals post PFA delivery: 0 min, 15 min, 1 hour, and 3 hours. Necropsy and histology followed the procedure. Results The optical signal is distinctly higher in intensity during the PFA pulse train. The optical signal showed an immediate significant decrease and a slow but steady decay over the mapping interval. Electrogram reduction accompanied PFA application and also showed a marked reduction over the mapping interval. The optical signal amplitudes were markedly lower when on the lesion compared to healthy non-ablated myocardium as predicted. Conclusions Preliminary results indicate that optical mapping detects immediate tissue changes during PFA at these energy levels and hence could be is a viable method of evaluating lesion formation during and after PFA energy application. The optical signal indicates that cell damage occurs immediately at these energy levels and continues to progress slowly in lesions made by PFA energy compared to those made by RF energy. The findings also suggest that optical mapping can identify acute lesions made with PFA energy in real-time implying that optical mapping could evolve as a PFA gap detector. Funding Acknowledgement Type of funding source: None

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.

PS01.103: THE UNUSUAL CAUSES OF ODYNOPHAGIA

2018 ◽  
Vol 31 (Supplement_1) ◽  
pp. 78-78 ◽  
Author(s):  
Kheng Tian Lim
Keyword(s):  
Complete Resolution ◽  
Conflicts Of Interest ◽  
Fish Bone ◽  
Esophageal Injury ◽  
Mediastinal Infection ◽  
Inflammatory Processes ◽  
History Of ◽  
Fish Ingestion ◽  
The Right ◽  
Esophageal Ulcers

Abstract Background Odynophagia can be caused by infective and non-infective inflammatory processes, benign and malignant esophageal disorders such as achalasia, gastro-esophageal reflux disease and carcinoma. Methods We described two unusual cases of odynophagia and their individual management. Results Case 1 is a 21 year-old Indian man presented with 2 days history of odynophagia after taking doxycycline capsules indicated for acne. An esophagogastroduodenoscopy (OGD) was performed and showed multiple mid esophageal ulcers. Esophageal biopsy taken showed inflammatory ulcer slough with no fungal infection, dysplasia or malignancy. Doxycycline was stopped and patient recovered with complete resolution of odynophagia. Case 2 is a 55 year-old Chinese man presented with 1 day history of odynophagia and severe chest pain after eating a bowl of hot fish soup. A CT Thorax was performed which showed a localised perforation of the right wall of the esophagus with extraluminal gas posterior to the trachea. An urgent OGD was performed and an L-shaped fish bone was removed successfully and an endoclip was applied to close the puncture hole of esophagus. Patient made a full recovery without any mediastinal infection. Conclusion Odynophagia from mid esophageal ulcers secondary to doxycycline intake should be recognized and can be easily managed by stopping the antibiotics with complete resolution of the symptom. Fish ingestion leading to sharp bone induced penetrating esophageal injury can be safely managed by endoscopic removal and endoclip application. Disclosure All authors have declared no conflicts of interest.

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

scholarly journals Atypical, polyarticular lipoma arborescens in a child

2016 ◽  
Vol 144 (11-12) ◽  
pp. 650-653
Author(s):  
Robert Semnic ◽  
Radoje Simic ◽  
Slavisa Djuricic ◽  
Oto Adjic ◽  
Filip Vanhoenacker
Keyword(s):  
Magnetic Resonance ◽  
Mr Imaging ◽  
Open Surgery ◽  
Literature Search ◽  
Histological Analysis ◽  
Rare Tumor ◽  
Rare Entity ◽  
Lipoma Arborescens ◽  
Diagnostic Protocol ◽  
The Right

Introduction. Lipoma arborescens is a rare, tumor-like lesion commonly involving synovial joints and less commonly bursae and synovial tendon sheaths. Case Outline. We report a case of a 12-year-old boy with symmetric involvement of the bicipitoradial bursae, synovial sheaths of extensor compartments of both hands and medial ankles. The diagnosis of polyarticular lipoma arborescens was proposed on magnetic resonance (MR) imaging and this diagnosis was histologically proven after biopsy of the bursae and later by open surgery of the synovial sheath of the right ankle tendons. Literature search was performed and twelve cases with polyarticular involvement were analyzed. Lipoma arborescens commonly involves suprapatellar recess of the knee and very rarely other joints or bursae. Histological analysis revealed an accompanying non-necrotizing granulomatous synovial inflammation. Conclusion. Polyarticular lipoma arborescens is a rare entity and symmetrical involvement of the joints other than the knees is exceedingly rare. MR imaging plays a significant role in the diagnostic protocol, and the characteristic fatty signal on MR imaging is highly suggestive of lipoma arborescens.

scholarly journals Histopathological evaluation of most frequent liver diseases in cats

2009 ◽  
Vol 63 (1-2) ◽  
pp. 103-112 ◽  
Author(s):  
Branislav Kureljusic ◽  
Darko Marinkovic ◽  
Jelena Obadovic ◽  
Milena Djordjevic ◽  
Vladimir Kukolj
Keyword(s):  
Liver Diseases ◽  
Histological Analysis ◽  
Final Diagnosis ◽  
Clinical Findings ◽  
Histological Changes ◽  
Histopathological Evaluation ◽  
Precise Diagnosis ◽  
Close Cooperation ◽  
The University ◽  
Age And Sex

Histological analysis was performed on the liver of 27 cats of different breeds, age and sex, autopsied at the Department of Pathological Morphology of the Faculty of Veterinary Medicine of the University of Belgrade, and findings showed lymphoplasmocytic cholangiohepatitis, different degrees of fibrosis, passive hyperemia, fatty changes, cholestase, and neoplasms. The mentioned entities occurred very rarely as individual morphological manifestations, because the liver has different functions so that one morphological change often causes others to follow. Thus, for example, fibrosis was often followed by intrahepatic cholestase. Histopathological evaluation of liver disease is important not only in the autopsied samples, but also in diagnostics of liver diseases, in samples obtained by biopsy, which is important for making a precise diagnosis. The interpretation of the established histological changes in the liver requires close cooperation between clinicians and pathologists, because the final diagnosis is made on the grounds of morphological, biochemical and clinical findings.

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.

Abstract 17710: Phrenic Nerve Injury Despite High-Output Pacing in Patients Undergoing Radiofrequency Catheter Ablation of Atrial Fibrillation

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Brett Izzo ◽  
Miki Yokokawa ◽  
Krit Jongnarangsin ◽  
Hamid Ghanbari ◽  
Rakesh Latchamsetty ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Phrenic Nerve ◽  
Maximum Output ◽  
Radiographic Findings ◽  
Long Duration ◽  
Mapping System ◽  
3D Mapping System ◽  
Rf Energy ◽  
The Right ◽  
High Output

Introduction: High-output pacing has been advocated as a strategy to avoid injury to the phrenic nerve (PN) during antral pulmonary vein (PV) isolation. We assessed the hypothesis that pacing does not prevent PN injury in patients undergoing radiofrequency (RF) ablation of atrial fibrillation (AF). Methods: The medical records of 198 consecutive patients (age=63±12 years, 129 men, ejection fraction=57±10%, LA=44±6mm, paroxysmal=49%) undergoing their first ablation procedure for AF were reviewed. All patients underwent antral PV isolation using a 3D mapping system (CARTO XP or CARTO 3) and a 3.5 mm irrigated-tip ablation catheter (maximum power, 25 W). Prior to RF energy delivery, high-output pacing (20 mA @ 10 ms, maximum output) was performed to asses for PN capture. Sites that afforded PN capture were avoided and RF energy was delivered at adjacent sites without PN capture. The 3-D maps were reviewed to identify the prevalence and sites of PN capture. Results: High-output pacing along the anterior right antrum resulted in PN capture in 35 patients (18%). The most common site with a positive response was the crux between the upper and lower PVs (60%), followed by the right superior PV (43%), and the right inferior PV (20%). Of the patients with PN capture, 49% had only one site of capture, 20% with two sites, and 31% had 3 or more sites. All PVs were isolated at the end of the procedure. Two patients (1%) developed PN injury (symptom onset on the day after the procedure), which was confirmed on radiography. In neither case was there evidence of PN capture during the procedure. Symptoms resolved in both patients within 3 months, with normalization of radiographic findings. Conclusions: High-output pacing along the anterior right PV antrum yields PN capture in roughly one-fifth of the patients undergoing PV isolation. Despite a negative response to pacing and alteration of the lesion set, PN injury may occur. The reason for this discordance is unknown, but may include the possibility that the capture threshold of the PN exceeds the maximum output of the stimulator, or that RF energy may injure the pericardiophrenic artery, which accompanies the PN. Avoiding high-power or long-duration lesions and high contact force in this region may minimize the risk of PN injury.

Dissection of the specimen from the right phrenic nerve and the pericardium, clipping and division of the thymic and lower thyroid veins

ASVIDE ◽  
2018 ◽  
Vol 5 ◽  
pp. 566-566
Author(s):  
Marcin Zieliński ◽  
Pawel Gwozdz ◽  
Katarzyna Solarczyk-Bombik ◽  
Michal Wilkojc ◽  
Wojciech Czajkowski ◽  
...  
Keyword(s):  
Phrenic Nerve ◽  
The Right

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.

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