Canine AV nodal artery: anatomical variations and a detailed description of cannulation technique

1987 ◽  
Vol 253 (4) ◽  
pp. H968-H973
Author(s):  
T. Mitsuoka ◽  
A. Pelleg ◽  
E. L. Michelson ◽  
L. S. Dreifus
Keyword(s):  
Conduction Block ◽  
Anatomical Variations ◽  
High Rate ◽  
Anatomical Location ◽  
Av Node ◽  
Pharmacological Agents ◽  
Artery Cannulation ◽  
Successful Cannulation ◽  
Selective Perfusion ◽  
Improved Technique

Cannulation of the atrioventricular (AV) nodal artery for selective perfusion of the AV node is a useful physiological method for evaluating the direct effects of pharmacological agents on the AV node. However, previous reports have not included a detailed description of the technique for AV nodal artery cannulation. Furthermore, successful cannulation is dependent on familiarity with the anatomical variations of the AV nodal artery [i.e., the most superior posterior septal artery (PSA)], which supplies blood to the AV nodal region and the posterior descending artery (PDA). The purpose of this report is to describe in detail the technique for cannulation of the AV nodal artery as well as the common anatomical variations of this artery. The anatomy of the PDA and PSA was studied at postmortem examination with ink injection in 30 dogs. Verification of the anatomical location of the AV nodal artery was aided by the induction of transient AV nodal conduction block following intracoronary administration of acetylcholine in the beating heart, as was done in previous studies. Two main variations and two subtypes of PDA anatomy and three main variations of AV nodal artery were found. Based on the present findings, an improved technique for cannulation of the AV nodal artery was established. Using this technique, we achieved a high rate of successful cannulation.

Effect of stimulation with light on synthesis and release of acetylcholine by an isolated mammalian retina

1976 ◽  
Vol 39 (6) ◽  
pp. 1210-1219 ◽  
Author(s):  
R. H. Masland ◽  
C. J. Livingstone
Keyword(s):  
Initial Rate ◽  
Horizontal Cells ◽  
High Rate ◽  
Cholinergic Synapse ◽  
Pharmacological Agents ◽  
Choline Incorporation ◽  
Rate Acceleration ◽  
Mammalian Retina ◽  
Release Of Acetylcholine ◽  
Stimulation Of

1. Acetylcholine synthesis and release were studied in rabbit retinas isolated from the eye and incubated under conditions in which their electrophysiological function is maintained. ACh synthesized from exogenous [14C] choline appeared in the retina at an initial rate of 16 nmol/g wet wt-h. Incorporation of labeled choline into ACh was accelerated by stimulation of the retina with light. 2. Retinas incubated for 40 min in the presence of labeled choline and then superfused with a medium containing an anticholinesterase released radioactive ACh into the perfusate. The rate of release increased approximately fourfold during stimulation with light. 3. When retinas were incubated with labeled choline and then superfused with medium containing no pharmacological agents, stimulation with light caused an increased release of choline into the perfusate. The recovery of labeled choline following stimulation was enhanced by hemicholinium 3. 4. Neither the light-induced release of ACh (in perfusate containing anticholinesterase) nor the light-induced release of choline (in perfusate containing no anticholinesterase) occurred if the perfusate contained 20 mM Mg2+ and 0.2 mM Ca2+. 5. Synthesis of ACh by the retina at a high rate, acceleration of choline incorporation by stimulation, and Ca2+-dependent release of ACh by stimulation are each presumptive evidence that the retina contains a cholinergic synapse. If this presumption is correct, one such synapse mayx be of an amacrine or bipolar cell since these cells can depolarize during illumination, whereas the predominant response of receptor and horizontal cells is hyperpolarization.

Inadvertent subclavian artery cannulation and options for management

Vascular ◽  
2014 ◽  
Vol 23 (2) ◽  
pp. 132-137 ◽  
Author(s):  
Albeir Y Mousa ◽  
Shadi Abu-Halimah ◽  
Aravinda Nanjundappa ◽  
Ali F AbuRahma
Keyword(s):  
Subclavian Artery ◽  
Central Line ◽  
Covered Stent ◽  
Closure Device ◽  
Anatomical Location ◽  
Daily Routine ◽  
Balloon Inflation ◽  
Artery Cannulation ◽  
Line Placement ◽  
Select Group

Central line placement is an integral part of our daily routine and although it is necessary in a select group of patients, serious complications may occur in up to 10% of cases. Inadvertent placement in the subclavian artery is considered to be one of the most challenging complications to the vascular specialist, which is mainly due to its deep anatomical location. Several endovascular options are available and should be tailored to fit each scenario. Herein, we present different approaches for the management of three cases of inadvertent subclavian artery cannulation. The first patient was treated with a covered stent, the second with prolonged balloon inflation, and the third with a closure device.

scholarly journals Cerebrospinal fluid fistula management – border pathology ENT-neurosurgery

2015 ◽  
Vol 62 (3) ◽  
pp. 303-306
Author(s):  
Corneliu Toader ◽  
◽  
Mioriţa Toader ◽  
Mircea Drăghici ◽  
Alina Oprea ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Intracranial Pressure ◽  
Dominant Role ◽  
Diagnostic Methods ◽  
High Rate ◽  
Anatomical Location ◽  
Cerebrospinal Fluid Fistula ◽  
Csf Fistula ◽  
Rate Of Success ◽  
Fluid Fistula

The authors of this article mention the diagnostic methods, the surgery techniques and the postoperative care for the patients diagnosed with fistula of cerebrospinal fluid (CSF). The surgery cure depends on many factors, including here the etiology of the rhino-basis defect, intracranial pressure, anatomical location of the rhino-basis defect and it is strictly individualized, which depends on the success of all surgery procedures. ENT physicians, together with the neurosurgeons, were able to have a dominant role in the diagnostic evaluation and in the treatment of skull base pathology can give us a CSF fistula. Nasal endoscopy has revolutionized the treatment of CSF fistula, with a high rate of success.

Application of Erythropoietin in Chronic Heart Failure Treatment

2020 ◽  
Vol 20 ◽  
Author(s):  
Atena Pourtaji ◽  
Vajiheh Jahani ◽  
Amirhossein Sahebkar ◽  
Thozhukat Sathyapalan ◽  
Amir Hooshang Mohammadpour
Keyword(s):  
Heart Failure ◽  
Animal Studies ◽  
Heart Function ◽  
The Elderly ◽  
Developed Countries ◽  
High Rate ◽  
Health Concern ◽  
Erythroid Progenitors ◽  
Traditional Role ◽  
Pharmacological Agents

: Heart failure (HF) is recognized as an important public health concern worldwide, especially in the developed countries, due to its high rate of morbidity and mortality. Although new pharmacological and non-pharmacological agents have improved the clinical sequelae of HF in patients, its mortality remains high, especially among the elderly. Erythropoietin (EPO), a glycoprotein, besides its traditional role in promoting erythropoiesis and production of erythroid progenitors, its beneficial role in reducing infarct area and improving heart function through EPO-induced anti-apoptotic and antioxidant effects have been increasingly recognized. This review gathers the evidence to date about the effectiveness of EPO in HF patients. In addition to the growing evidence of EPO in treatment of HF in the animal studies for improving cardiac function and infarct size, more clinical studies are needed to assess the role of EPO treatment in the management of HF.

scholarly journals A case of infra-nodal Wenckebach conduction block with alternating bundle branch block

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Pichmanil Khmao ◽  
Chun Hwang ◽  
Hui-Nam Pak
Keyword(s):  
Conduction Block ◽  
Conduction Delay ◽  
Av Node ◽  
Bundle Branch Block ◽  
Case Presentation ◽  
Short Cycle ◽  
Purkinje System ◽  
Av Conduction ◽  
Premature Beats ◽  
Decremental Conduction

Abstract Background Atrioventricular (AV) node normally has decremental conduction property and a longer refractory period than His-Purkinje system (HPS). This results in AV conduction delay or block at the level of AV node in response to short-coupled atrial premature beats. Prolonged refractoriness in HPS can produce unusual physiological patterns of AV conduction such as conduction delay or infra-nodal block in the distal elements of HPS. Case presentation We present a case in which atrial premature stimulation produces infra-nodal Wenckebach conduction block which initiates long-short cycle sequence within the bundle branches resulted in alternating bundle branch block and atypical pattern of Ashman phenomenon. Conclusions This case highlights the importance of recognizing the unusual physiological AV conduction patterns of HPS. The long-short cycle sequence in the bundle branches of distal HPS and linking phenomenon can result in alternating bundle branch block without the presence of HPS disease.

Morphology and electrophysiology of the mammalian atrioventricular node

1988 ◽  
Vol 68 (2) ◽  
pp. 608-647 ◽  
Author(s):  
F. L. Meijler ◽  
M. J. Janse
Keyword(s):  
Mammalian Species ◽  
Conduction Block ◽  
Atrioventricular Node ◽  
Conduction Delay ◽  
Conduction Time ◽  
Av Node ◽  
Crista Terminalis ◽  
His Bundle ◽  
Transitional Cells ◽  
Av Bundle

The AV node of those mammalian species in which it has been thoroughly investigated (rabbit, ferret, and humans) consists of various cell types: transitional cells, midnodal (or typical nodal cells), lower nodal cells, and cells of the AV bundle. There are at least two inputs to the AV node, a posterior one via the crista terminalis and an anterior one via the interatrial septum, where atrial fibers gradually merge with transitional cells. The role of a possible third input from the left atrium has not been investigated. Since the transition from atrial fibers to nodal fibers is gradual, it is very difficult to define the "beginning" of the AV node, and gross measurements of AV nodal length may be misleading. Histologically, the "end" of the AV node is equally difficult to define. At the site where macroscopically the AV node ends, at the point where the AV bundle penetrates into the membranous septum, typical nodal cells intermingle with His bundle cells. A conspicuous feature, found in all species studied, is the paucity of junctional complexes, most marked in the midnodal area. The functional counterpart of this is an increased coupling resistance between nodal cells. An electrophysiological classification of the AV nodal area, based on transmembrane action potential characteristics during various imposed atrial rhythms (rapid pacing, trains of premature impulses), into AN (including ANCO and ANL), N, and NH zones has been described by various authors for the rabbit heart. In those studies in which activation patterns, transmembrane potential characteristics, and histology have been compared, a good correlation has been found between AN and transitional cells, N cells and the area where transitional cells and cells of the beginning of the AV bundle merge with midnodal cells, and NH cells and cells of the AV bundle. Dead-end pathways correspond to the posterior extension of the bundle of lower nodal cells and to anterior overlay fibers. During propagation of a normal sinus beat, activation of the AN zone accounts for at least 25% of conduction time from atrium to His bundle, the small N zone being the main source of AV nodal delay. Cycle length-dependent conduction delay is localized in the N zone. Conduction block of premature atrial impulses can occur both in the N zone and in the AN zone, depending on the degree of prematurity. Several factors determining AV nodal conduction delay have been identified.(ABSTRACT TRUNCATED AT 400 WORDS)

Nodal recovery, dual pathway physiology, and concealed conduction determine complex AV dynamics in human atrial tachyarrhythmias

2012 ◽  
Vol 303 (10) ◽  
pp. H1219-H1228 ◽  
Author(s):  
Michela Masè ◽  
Leon Glass ◽  
Marcello Disertori ◽  
Flavia Ravelli
Keyword(s):  
Wide Spectrum ◽  
Surrogate Data ◽  
High Rate ◽  
Intermediate Step ◽  
Av Node ◽  
Atrial Tachyarrhythmias ◽  
Wide Range ◽  
Ventricular Activation ◽  
Dual Pathway ◽  
Nodal Properties

The genesis of complex ventricular rhythms during atrial tachyarrhythmias in humans is not fully understood. To clarify the dynamics of atrioventricular (AV) conduction in response to a regular high-rate atrial activation, 29 episodes of spontaneous or pacing-induced atrial flutter (AFL), covering a wide range of atrial rates (cycle lengths from 145 to 270 ms), were analyzed in 10 patients. AV patterns were identified by applying firing sequence and surrogate data analysis to atrial and ventricular activation series, whereas modular simulation with a difference-equation AV node model was used to correlate the patterns with specific nodal properties. AV node response at high atrial rate was characterized by 1) AV patterns of decreasing conduction ratios at the shortening of atrial cycle length (from 236.3 ± 32.4 to 172.6 ± 17.8 ms) according to a Farey sequence ordering (conduction ratio from 0.34 ± 0.12 to 0.23 ± 0.06; P < 0.01); 2) the appearance of high-order alternating Wenckebach rhythms, such as 6:2, 10:2, and 12:2, associated with ventricular interval oscillations of large amplitude (407.7 ± 150.4 ms); and 3) the deterioration of pattern stability at advanced levels of block, with the percentage of stable patterns decreasing from 64.3 ± 35.2% to 28.3 ± 34.5% ( P < 0.01). Simulations suggested these patterns to originate from the combined effect of nodal recovery, dual pathway physiology, and concealed conduction. These results indicate that intrinsic nodal properties may account for the wide spectrum of AV block patterns occurring during regular atrial tachyarrhythmias. The characterization of AV nodal function during different AFL forms constitutes an intermediate step toward the understanding of complex ventricular rhythms during atrial fibrillation.

scholarly journals Morphological Variations in the Anatomy of Caecum and Appendix - A Cadaveric Study

2012 ◽  
Vol 01 (01) ◽  
pp. 030-035 ◽  
Author(s):  
Arindom Banerjee ◽  
I. Anil Kumar ◽  
Arunabha Tapadar ◽  
M Pranay
Keyword(s):  
Emergency Surgery ◽  
Average Length ◽  
Iliac Fossa ◽  
Anatomical Variations ◽  
Vermiform Appendix ◽  
Anatomical Location ◽  
Morphological Variations ◽  
Clinical Presentations ◽  
Abdominal Operations ◽  
The Right

Abstract Background : Appendicitis is one of the most common clinical conditions that require emergency surgery. Variations in anatomical location of appendix can result in different clinical presentations. Anatomical and topographical variations of the caecum are also known to occur. Anatomical variations in caecum have been observed along with the appendix in this study. Aims: To study the variations in the size, shape, position and arterial supply of the caecum and appendix in individuals of different sex and age, a thorough knowledge of which will aid surgeons in performing various abdominal operations in adults and children. Material and methods: The study was carried out on 25 adult cadavers over a period of 3 years. The anatomy of caecum and appendix was studied in detail. Results : The normal position of caecum and appendix in adult cadavers was found to be in the right iliac fossa. In all specimens the shape of caecum was adult (ampullary) type and it was supplied normally in all cases from a branch of the superior mesenteric artery. The appendix was found in the retro-caecal position in majority of cases with a complete meso-appendix in four and an additional blood supply via the artery of Sesachalam was found in two cases. Conclusions: Vermiform appendix is characterized by variability of its location and morphology. The ultimate position of the appendix is influenced by the changes in position and shape which the caecum undergoes during development and growth. The present study observed the appendix and caecum to be found in their normal positions in majority of cases. The average length of caecum and appendix was found to be more in males as compared with females. Appendicitis is one of the most common diseases that need emergency surgery. Variations in anatomical position cause different clinical presentations. A thorough knowledge of normal anatomy and variations of the caecum and appendix is very important to the surgeon performing abdominal operations in adults, children and infants as it helps them to make optimal diagnosis of various pathological conditions related to these organs and treat accordingly.

scholarly journals Scale Ultrasound-guided Radial Artery Cannulation in infant: A Randomized Controlled Trial

2020 ◽  
Author(s):  
Fei Yang ◽  
Shangyingying Li ◽  
Hang Chen ◽  
Rui Jiang ◽  
Xuanqin Wang ◽  
...  
Keyword(s):  
Success Rate ◽  
Radial Artery ◽  
Arterial Puncture ◽  
Arterial Cannulation ◽  
Ultrasound Guided ◽  
Radial Artery Cannulation ◽  
Artery Cannulation ◽  
Successful Cannulation ◽  
Ultrasound Group ◽  
Initial Success Rate

Abstract BackgroundCannulation of the radial artery can be extremely challenging in infants. Scale ultrasound can provide accurate arterial location and guidance for operators. We hypothesized that scale ultrasound helps increase the initial success rate of radial artery cannulation in this population.MethodThis is a double-blinded, parallel-group trial prospective study. Seventy-six infants aged 0–3 months who needed arterial puncture after general anesthesia were randomly divided into two groups (1:1 ratio): the scale ultrasound group and the traditional ultrasound group. Patients in the traditional ultrasound group underwent conventional ultrasound-guided radial artery puncture, whereas radial artery puncture was guided by scale ultrasound in the scale ultrasound group. The primary endpoints were the success rate of the first attempt and the total success rate of arterial cannulation. The secondary endpoints were the time of ultrasound location, the time of the needle entering the radial artery, the time of successful cannulation, times of the arterial puncture and the incidence of vascular complications. Data analysis was performed with Minitab 18.0 (Minitab Inc., USA).Main ResultsThe success rate of the first attempt and the total success rate of arterial cannulation were 92.1% (35/38) and 100% (38/38) in the scale ultrasound group and 50% (19/38) and 86.8% (33/38) in the traditional ultrasound group (p < 0.005), respectively. The median time to ultrasound location, needle entry into the radial artery and successful cannulation in the scale ultrasound group were significantly shorter than those in the traditional ultrasound group: 10 (8.0, 17.2) s, 15 (11.7, 20) s and 65 (53.8, 78.5) s vs 30 (26.5, 43.5) s, 35 (23, 51) s and 224.5 (123.5, 356) s (p < 0.001), respectively. The incidence of hematoma was higher in the traditional group (p < 0.005).ConclusionsScale ultrasound-guided radial arterial cannulation can significantly improved initial success rate and overall success rate, shorten puncture time in infant,compared with that achieved with the use of traditional ultrasound guidance.

Intra-Operative Phlebography of the Short Saphenous Vein

1987 ◽  
Vol 2 (4) ◽  
pp. 241-247 ◽  
Author(s):  
Leonardo Corcos ◽  
Giampiero Peruzzi ◽  
Vincenzina Romeo ◽  
Carlo Fiori
Keyword(s):  
Saphenous Vein ◽  
Anatomical Variations ◽  
High Rate ◽  
Surgical Trauma ◽  
Negative Effects ◽  
Cosmetic Results ◽  
Technical Developments ◽  
Short Saphenous Vein

The short saphenous vein is more and more often held responsible for the onset and development of varicose conditions and post-operative recurrence. In order to perform complete posterior saphenectomy account must be taken of the frequent anatomical variations in the outflow of this vein. A method of intra-operative phlebography of the short saphenous vein has been developed. The results confirm the high rate of the anatomical variations. Intra-operative phlebography facilitates complete posterior saphenectomy without negative effects in terms of surgical trauma and cosmetic results, thanks to the new technical developments.

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