Abstract 60: Inducible Arrythmogenicity of Direct Current Electroporation Ablation: Insight from a Series of Acute Canine Studies

2017 ◽  
Vol 121 (suppl_1) ◽  
Author(s):  
Alan Sugrue ◽  
Chance Witt ◽  
Christopher V DeSimone ◽  
Deepak Padnanabhan ◽  
Ammar Killu ◽  
...  
Keyword(s):  
Direct Current ◽  
Superior Vena ◽  
Pulmonary Veins ◽  
Pulse Length ◽  
Experimental Studies ◽  
Tissue Destruction ◽  
Ecg Gating ◽  
Actual Mechanism ◽  
Membrane Poration ◽  
Current Energy

Background: The use of direct current electroporation has the potential for significant utility because of its non-thermal approach to tissue destruction. However, the fear of inducibility of cardiac arrhythmias (particular ventricular fibrillation) when using electroporation remains of concern due to membrane poration and ion flux during periods of vulnerability occurring in ventricular repolarization. Objectives: Critically examine the incidence of arrhythmias in a series of acute canine studies to retrospectively determine cause and safe electoporative dosing margins. Methods: We performed electroporation ablation in 6 acute canine studies. These were experimental studies performed at sites critical in arrhytmogenesis. Sites included the pulmonary veins, left atrial appendage, superior vena cavae, right atrium and ventricle. Electroporation was delivered using an ECG gating algorithm so that QRS complexes are tagged and direct current energy is not delivered during the vulnerable portion of the T wave. Results: In 6 acute canine experiments, we delivered a total of 62 electroporation applications for ablation purposes. The average electroporation dosage delivered involved an average of 1427 Volts (range 750-3000 V), Pulse length of 100 ms, and number of pulses of 20.2 (range 10-100). AF was induced in 27.4% of electroporiatve applications. Atrial flutter/tachycardia occurred in 8.1%. VF occurred in only one application at a location of the left superior pulmonary vein. Conclusion: These data suggest that induction of VF is relatively uncommon with ECG gating and highlight its importance when using this modality. However, the induction of AF occurs with higher frequency. The actual mechanism as to why this occurs requires further systematic study.

Single-Patch Fold-Back Technique for Augmentation of the Superior Vena Cava in Sinus Venosus Atrial Septal Defect Associated with Partial Anomalous Pulmonary Venous Return

2015 ◽  
Vol 17 (6) ◽  
pp. 282
Author(s):  
Suguru Ohira ◽  
Kiyoshi Doi ◽  
Takeshi Nakamura ◽  
Hitoshi Yaku
Keyword(s):  
Atrial Septal Defect ◽  
Superior Vena Cava ◽  
Septal Defect ◽  
Venous Return ◽  
Superior Vena ◽  
Pulmonary Veins ◽  
Vena Cava ◽  
Sinus Venosus ◽  
Right Atrial ◽  
Anomalous Pulmonary Venous Return

Sinus venosus atrial septal defect (ASD) is usually associated with partial anomalous pulmonary venous return (PAPVR) of the right pulmonary veins to the superior vena cava (SVC), or to the SVC-right atrial junction. Standard procedure for repair of this defect is a patch roofing of the sinus venosus ASD and rerouting of pulmonary veins. However, the presence of SVC stenosis is a complication of this technique, and SVC augmentation is necessary in some cases. We present a simple technique for concomitant closure of sinus venosus ASD associated with PAPVR and augmentation of the SVC with a single autologous pericardial patch.

Congenital Horner and Scimitar syndrome in a newborn: a previously unreported combination

2020 ◽  
Vol 13 (11) ◽  
pp. e238018
Author(s):  
Joana Carvalho ◽  
Mariana Maia ◽  
Ágata Mota ◽  
Teresa Martins
Keyword(s):  
Multidisciplinary Approach ◽  
Septal Defect ◽  
Inferior Vena ◽  
Superior Vena ◽  
Pulmonary Veins ◽  
Vena Cava ◽  
Scimitar Syndrome ◽  
Left Superior Vena Cava ◽  
Dilated Coronary Sinus ◽  
Rule Out

Here we report a case of a term newborn presenting with left palpebral ptosis, anisocoria and heterochromia as well as cleft palate and heart murmur. Congenital Horner syndrome was suspected and a thoracoabdominal CT scan was performed to rule out neuroblastoma. This revealed an anomalous drainage of right pulmonary veins to a collector that drains to the inferior vena cava, leading to the diagnosis of Scimitar syndrome. Echocardiogram showed an ostium secundum atrial septal defect, enlarged right chambers and a dilated coronary sinus due to a persistent left superior vena cava. The combination of Horner and Scimitar syndrome has never been described before. This case should encourage clinicians to use a multidisciplinary approach in order to guarantee an adequate diagnosis and management.

scholarly journals The effects of transcranial direct current stimulation on gait in patients with Parkinson’s disease: a systematic review

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Fateme Pol ◽  
Mohammad Ali Salehinejad ◽  
Hamzeh Baharlouei ◽  
Michael A. Nitsche
Keyword(s):  
Systematic Review ◽  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Randomized Clinical Trials ◽  
Cortical Excitability ◽  
Experimental Studies ◽  
Gait Rehabilitation ◽  
Direct Current Stimulation

Abstract Background Gait problems are an important symptom in Parkinson’s disease (PD), a progressive neurodegenerative disease. Transcranial direct current stimulation (tDCS) is a neuromodulatory intervention that can modulate cortical excitability of the gait-related regions. Despite an increasing number of gait-related tDCS studies in PD, the efficacy of this technique for improving gait has not been systematically investigated yet. Here, we aimed to systematically explore the effects of tDCS on gait in PD, based on available experimental studies. Methods Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) approach, PubMed, Web of Science, Scopus, and PEDro databases were searched for randomized clinical trials assessing the effect of tDCS on gait in patients with PD. Results Eighteen studies were included in this systematic review. Overall, tDCS targeting the motor cortex and supplementary motor area bilaterally seems to be promising for gait rehabilitation in PD. Studies of tDCS targeting the dorosolateral prefrontal cortex or cerebellum showed more heterogeneous results. More studies are needed to systematically compare the efficacy of different tDCS protocols, including protocols applying tDCS alone and/or in combination with conventional gait rehabilitation treatment in PD. Conclusions tDCS is a promising intervention approach to improving gait in PD. Anodal tDCS over the motor areas has shown a positive effect on gait, but stimulation of other areas is less promising. However, the heterogeneities of methods and results have made it difficult to draw firm conclusions. Therefore, systematic explorations of tDCS protocols are required to optimize the efficacy.

scholarly journals P649 Before and after: sinus venosus atrial septal defect

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
I Marco Clement ◽  
R Eiros ◽  
R Dalmau ◽  
T Lopez ◽  
G Guzman ◽  
...  
Keyword(s):  
Atrial Septal Defect ◽  
Left Atrium ◽  
Atrial Flutter ◽  
Superior Vena Cava ◽  
Right Atrium ◽  
Septal Defect ◽  
Superior Vena ◽  
Pulmonary Veins ◽  
Vena Cava ◽  
The Right

Abstract Introduction The diagnosis of sinus venosus atrial septal defect (SVASD) is complex and requires special imaging. Surgery is the conventional treatment; however, transcatheter repair may become an attractive option. Case report A 60 year-old woman was admitted to the cardiology department with several episodes of paroxysmal atrial flutter, atrial fibrillation and atrioventricular nodal reentrant tachycardia. She reported a 10-year history of occasional palpitations which had not been studied. A transthoracic echocardiography revealed severe right ventricle dilatation and moderate dysfunction. Right volume overload appeared to be secondary to a superior SVASD with partial anomalous pulmonary venous drainage. A transesophageal echocardiography confirmed the diagnosis revealing a large SVASD of 16x12 mm (Figure A) with left-right shunt (Qp/Qs 2,2) and two right pulmonary veins draining into the right superior vena cava. Additionally, it demonstrated coronary sinus dilatation secondary to persistent left superior vena cava. CMR and cardiac CT showed right superior and middle pulmonary veins draining into the right superior vena cava 18 mm above the septal defect (Figures B and C). After discussion in clinical session, a percutaneous approach was planned to correct the septal defect and anomalous pulmonary drainage. For this purpose, anatomical data obtained from CMR and CT was needed to plan the procedure. During the intervention two stents graft were deployed in the right superior vena cava. The distal stent was flared at the septal defect level so as to occlude it while redirecting the anomalous pulmonary venous flow to the left atrium (Figure D). Control CT confirmed the complete occlusion of the SVASD without residual communication from pulmonary veins to the right superior vena cava or the right atrium (Figure E). Anomalous right superior and middle pulmonary veins drained into the left atrium below the stents. Transthoracic echocardiographies showed progressive reduction of right atrium and ventricle dilatation. The patient also underwent successful ablation of atrial flutter and intranodal tachycardia. She is currently asymptomatic, without dyspnea or arrhythmic recurrences. Conclusions In this case, multimodality imaging played a key role in every stage of the clinical process. First, it provided the diagnosis and enabled an accurate understanding of the patient’s anatomy, particularly of the anomalous pulmonary venous connections. Secondly, it allowed a transcatheter approach by supplying essential information to guide the procedure. Finally, it assessed the effectiveness of the intervention and the improvement in cardiac hemodynamics during follow-up. Abstract P649 Figure.

Characterization of an Improved dc Plasma Excitation Source

1980 ◽  
Vol 34 (1) ◽  
pp. 24-30 ◽  
Author(s):  
G. N. Coleman ◽  
W. P. Braun ◽  
A. M. Allen
Keyword(s):  
Thermal Conductivity ◽  
Direct Current ◽  
Direct Evidence ◽  
Plasma Jet ◽  
Sample Introduction ◽  
Direct Current Plasma ◽  
Actual Mechanism ◽  
Improved Stability ◽  
Plasma Excitation

Several modifications of the direct current plasma jet have resulted in significantly enhanced analysis capabilities. Reducing the electrode angle, decreasing the aerosol chimney size, and operating in a diffuse mode with helium have provided improved stability, sensitivity, freedom from interferences, and detection limits. While the actual mechanism of the helium enhancement is not clear, no direct evidence was found which supports participation in the excitation step. Rather, improved desolvation, vaporization and possibly sample introduction result from the thermal conductivity of helium being much greater than that of argon.

scholarly journals Comparison of catheter ablation using radiofrequency versus direct current energy: Biophysical, electrophysioiogic and pathologic observations

1991 ◽  
Vol 18 (4) ◽  
pp. 1091-1097 ◽  
Author(s):  
Shoei K.Stephen Huang ◽  
Anna R. Graham ◽  
Michael A. Lee ◽  
Michael E. Ring ◽  
Grace D. Gorman ◽  
...  
Keyword(s):  
Catheter Ablation ◽  
Direct Current ◽  
Current Energy

ANOMALIES OF THE PULMONARY VEINS AND THEIR SURGICAL SIGNIFICANCE

PEDIATRICS ◽  
1952 ◽  
Vol 9 (2) ◽  
pp. 152-166
Author(s):  
HARRY G. PARSONS ◽  
ANN PURDY ◽  
BRUCE JESSUP
Keyword(s):  
Superior Vena Cava ◽  
Clinical Symptoms ◽  
Superior Vena ◽  
Pulmonary Veins ◽  
Vena Cava ◽  
Ductus Venosus ◽  
Return Flow ◽  
Right Heart ◽  
Surgical Measures ◽  
The Right

The successful operations upon abnormalities of the outflow tracts of the heart suggest that surgical measures may also be applied to the correction of abnormal inflow tracts. Technically the anastomosis of veins to the auricle has been proved feasible in the experimental animal. Therefore, it should be possible to correct abnormally placed pulmonary veins in man. A wide variety of such anomalies occur. In 55 of 136 reported cases, all the oxygenated blood from the lungs was returned to the right heart through anomalous vessels. Thirty-five per cent of these cases of complete diversion were accompanied by other major cardiac defects. It is estimated that 50% or more of the return flow from the lungs must reach the right heart to produce clinical symptoms. Two cases are presented of persistence of the left superior vena cava which transmitted all the freshly oxygenated blood to the right auricle, by way of the left innominate and the right superior vena cava. The clinical picture was that of growth retardation, minimal cyanosis, a huge hyperactive heart, a loud left mesocardial systolic murmur, pulsating shadows in both upper pulmonary fields, and nearly identical oxygen-saturation of blood obtained from the right heart and femoral artery. One case is reported in which all the oxygenated blood from the lungs is carried to the right auricle by way of the ductus venosus. Surgical correction of the abnormality of these cases by transplantation of one or more of the veins would have been possible. However, no case known to the authors has yet been successfully corrected.

TYPES OF CORRECTION OF THE SUPRACARDIAC FORM OF PARTIAL ABNORMAL DRAINAGE OF THE PULMONARY VEINS. WARDEN PROCEDURE

2021 ◽  
pp. 28-31
Author(s):  
Inkar Sagatov ◽  
Nurzhan Dosmailov
Keyword(s):  
Left Atrium ◽  
Superior Vena Cava ◽  
Right Atrium ◽  
Superior Vena ◽  
Pulmonary Veins ◽  
Vena Cava ◽  
Artificial Circulation ◽  
The Right

The article describes the types of correction of the supracardial form of abnormal drainage of the pulmonary veins. One of the methods of correcting this defect is the Warden operation, which includes: after sternotomy, connection of artificial circulation, cardioplegia, the superior vena cava is cut off, the proximal end is sutured. Next, a right atriotomy is performed, an anastomosis is formed using an autopericardial patch between the abnormal drainage and the left atrium through the ASD. Then an anastomosis is formed between the auricle of the right atrium and the distal end of the superior vena cava. As a result, blood from the abnormal pulmonary veins begins to drain into the left atrium through the ASD.

Selective parasympathectomy of automatic and conductile tissues of the canine heart

1985 ◽  
Vol 248 (1) ◽  
pp. H61-H68 ◽  
Author(s):  
W. C. Randall ◽  
J. L. Ardell
Keyword(s):  
Vagal Stimulation ◽  
Superior Vena ◽  
Sympathetic Innervation ◽  
Pulmonary Veins ◽  
Vena Cava ◽  
Dorsal Surface ◽  
Atrial Pacing ◽  
Canine Heart ◽  
Surgical Interventions ◽  
The Right

From right thoracotomy (T4-T5), the canine heart was suspended in its pericardium to expose its major venous inputs. Vagal and sympathetic trunks were prepared for electrical stimulation (10-20 Hz, 5.0 ms, 3-5 V) before and after each separate denervation procedure. Vagal stimulation was instituted with and without concurrent atrial pacing. The following surgical interventions were performed. 1) The superior vena cava was cleared of connective and nervous tissues from the pericardial reflection caudally to the level of the right pulmonary artery. 2) The azygos vein was cleared, tied, and sectioned. 3) The right pulmonary veins were isolated and cleared intrapericardially. 4) The dorsal surface of the atria was dissected between the right and left pulmonary veins and painted with phenol. Each step in the procedure elicited successive stepwise deletion of parasympathetic influences on sinoatrial tissues of the canine heart with only minor ablation of sympathetic inputs. 5) Dissection of the triangular fat pad at the junction of the inferior vena cava and inferior left atrium eliminated the remaining parasympathetic efferent input to the heart with dramatic deletion of atrioventricular block during either left or right vagal stimulation, again with preservation of most of the sympathetic innervation. These experiments clearly demonstrate differential and selective inputs of parasympathetic pathways to sinoatrial (SAN) and atrioventricular (AVN) regions of the dog heart but relatively little interference with sympathetic distributions.(ABSTRACT TRUNCATED AT 250 WORDS)

Cor Triatriatum in Association With a Unique Form of Partial Anomalous Pulmonary Venous Connection

2021 ◽  
pp. 215013512110469
Author(s):  
Lou Capecci ◽  
Richard D. Mainwaring ◽  
Inger Olson ◽  
Frank L. Hanley
Keyword(s):  
Superior Vena Cava ◽  
Superior Vena ◽  
Pulmonary Veins ◽  
Vena Cava ◽  
Venous Drainage ◽  
Cor Triatriatum ◽  
Unique Form ◽  
Elective Repair ◽  
The Right ◽  
Anomalous Pulmonary Venous Connection

Cor triatriatum may be associated with abnormalities of pulmonary venous anatomy. This case report describes a unique form of partial anomalous pulmonary venous connection. The patient presented at 5 weeks of age with symptoms of tachypnea and poor feeding. Echocardiography demonstrated cor triatriatum and partial anomalous pulmonary venous drainage of the right upper lung. The patient underwent urgent repair of cor triatriatum. It was elected to not address the partial anomalous pulmonary venous connection at that time. The patient returned at age 19 months for elective repair of the anomalous pulmonary venous connection. There was also a large vein connecting the right lower pulmonary veins to the superior vena cava. This was repaired by dividing the superior vena cava along a vertical axis to redirect the flow of the anomalous pulmonary veins through the connecting vein to the left atrium. This report describes the anatomy and surgical approach to a unique form of anomalous pulmonary venous connection.

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