Superior Vena Cava-right Atrium Research Articles

Injury to the sinus nodal artery during radiofrequency ablation of atrial fibrillation and atrial tachycardia: its prevalence and treatment with percutaneous coronary intervention

Abstract Background/Introduction Injury to the sinus node artery (SNA) leading to SN dysfunction during radiofrequency catheter ablation (RFCA) of atrial Fibrillation (AF) and atrial tachycardia (AT) has been reported. Purpose The purpose of this study was to elucidate the prevalence and clinical course of SNA injuries during RFCA of AF/AT and examine the efficacy of the percutaneous coronary intervention (PCI) to restore SN function. Methods We retrospectively analyzed data from 6,906 consecutive patients (pts) who underwent RFCA of AF/AT (6,379 pts with AF ablation and 527 pts with AT ablation) in two institutions between January 2013 and December 2022. Results Among 6,906 pts, 9 (0.13%) pts developed SN dysfunction due to SNA injury during RFCA (8 with AF, 1 with AT). Acute SNA injury (total occlusion or severe narrowing of the SNA) was confirmed by coronary angiography (CAG) during the RFCA session in 8/9 pts. In the remaining patient, SNA injury was suspected based on the CT angiography. The culprit sites of the SNA injury were located at the septal site of the superior vena cava-right atrium junction in 4 pts (44%), on the left atrial appendage ridge in 3 (33%), on the roof of the left atrium adjacent to the right superior pulmonary vein in 1 (11%), and in the persistent left superior vena cava in 1 (11%). PCI to the occluded SNA was performed in 8 of the 9 pts: 1) coronary blood flow of the SNA was restored by a 0.014" guidewire advancement into the occluded artery using a micro-catheter followed by direct nitroprusside injection in 4 pts; 2) the direct balloon angioplasty using 0.75-1.5 mm diameter balloons was required to maintain the blood flow of SNA in 3 pts; and 3) CAG revealed spontaneous recovery of the blood flow of SNA in one pt. The remaining patient did not receive the CAG/PCI. All 8 pts who underwent the PCI resulted in restoration of normal sinus rhythm. During a median of 44 months follow-up, all 8 pts who received the PCI maintained normal sinus rhythm, while one patient without PCI demonstrated persistent SN dysfunction. Conclusions SNA injury during RFCA is a rare but critical complication. Prompt recognition by CAG and subsequent PCI effectively restores SN function in pts with unexpected SN dysfunction during RFCA procedures.

Successful catheter ablation of atrial tachycardia initiated with orthodromic capture of superior vena cava potentials.

Acase of successful catheter ablation of paroxysmal atrial fibrillation and atrial tachycardia is reported. After pulmonary vein isolation, atrial tachycardia was induced by the use of isoproterenol and burst pacing from the catheter in the right atrium. An attempt was made to create athree-dimensional (3D) map of the atrial tachycardia, but the atrial tachycardia was terminated in the middle of the mapping. The 3D map was insufficient but indicated that the superior vena cava was involved in the circuit. When the intracardiac electrograms were reviewed, it was found that the atrial tachycardia was initiated with orthodromic capture of superior vena cava potentials and it was considered that the atrial tachycardia involved the superior vena cava-right atrium junction. Accordingly, superior vena cava isolation was performed. After that, atrial fibrillation and atrial tachycardias were not induced by the use of isoproterenol and burst pacing. In this case, an intracardiac electrogram at the time of induction of the tachycardia was helpful for understanding the circuit of the tachycardia.

Reliability of intra-atrial ECG method of insertion of central venous line through right internal jugular vein when compared to formula and radiological landmark method: a prospective randomized study

BackgroundIdeal position of central venous catheter tip should be within 2 cm above and 1 cm below superior vena cava–right atrium (SVC-RA) junction. The objective of the study was to compare intra-atrial ECG method of Central venous catheterization of right internal jugular vein (IJV) with traditional methods. A prospective randomized trial enrolling 90 patients were alternatively allocated to three groups and comparison of intra-atrial electrocardiography, radiological landmark and Pere’s formula method for correct positioning of central venous catheter tip were done and tip position were confirmed with post-procedural TEE (transesophageal echocardiography).ResultsCatheter tip was present at the ideal position in 100% cases in intra-atrial ECG method compared to only 23.4% in formula method and 93.3% in landmark method (p value 0.001). In intra-atrial method group, the central venous catheter tip was placed perfectly in all patients, position of the catheter tip was not acceptable in 71.4% of the patients where formula method is used and not acceptable in 11.1% when landmark method is used (p value 0.001). However, we did not encounter any catheter related complications in any of these groups.ConclusionsIntra-atrial ECG method carries the advantage of ideal positioning of the central venous catheter tip by right IJV route in almost all cases when compared to conventional formula and landmark method to some extent. Also, immediate confirmation and real time verification of central venous catheter (CVC) tip is possible, thereby avoids the need for post-procedural chest X-ray and other methods of central venous placement confirmation like arterial blood gas analysis etc., Hence, intra-atrial ECG method is cost effective and safer for confirmation of CVC tip in all the situations.

Totally Endoscopic Surgery for Repairing Sinus Venosus Atrial Septal Defect Using Double-Patch Technique on Beating Heart.

Minimally invasive cardiac surgery has not been widely applied in repairing sinus venosus atrial septal defect (SV-ASD). Most were minithoracotomy using the single-patch technique for patients with anomalous pulmonary veins (APVs) connecting to the superior vena cava-right atrium (SVC-RA) junction. It is unclear whether patients with APVs draining high to the SVC can be repaired safely and effectively through port access. From May 2019 to October 2022, 11 consecutive SV-ASD patients with APVs connecting high to the SVC were enrolled in this prospective study. One 12 mm port and 2 trocars (5.5 mm and 10 mm) were established. The pleural and pericardial spaces were filled with CO2. The SVC was snared just below the azygos vein. The RA incision was longitudinally extended along the SVC-RA junction to the SVC. The bovine pericardial patches were used to redirect the APV flow to the left atrium through the ASD and to enlarge the SVC and the SVC-RA junction. There were no early or late deaths and no reoperations. The concomitant procedures included 5 patients (45.5%) with patent foramen ovale closure, 2 with ASD extension, and 3 with tricuspid valve repair. No endoscopic failure was recorded. The average cardiopulmonary bypass and operative times were 96 (23) min and 190 (30) min, respectively. No cases of venous stenosis or sinus node dysfunction were noted during follow-up of 16.4 ± 12.2 months. SV-ASD with the APVs draining high to the SVC could be repaired safely and effectively through port access with a double-patch technique.

An unusual cause of chest pain.

A 78-year-old female with a history of lymphoma presented to the emergency department (ED) because of chest discomfort. A chest x-ray was performed and revealed the diagnosis. As shown in Figure 1, the patient's Port-A-Cath fractured and part of it was displaced to the right heart (Figures 1 and 2). The discontinuity was noted at the level of the left first rib and clavicle. The mid and distal portion migrated and was seen within the distal superior vena cava, right atrium, and possibly projecting into the right ventricle. The decision was made to admit the patient to conduct endovascular retrieval. One of the rare complications of a Port-A-Cath placement is its fracture and displacement into the heart. The most common site of displacement is at the superior vena cava-right atrium junction, and it can further embolize into the right ventricle.1 This complication is rare, with a reported incidence of 0.4%–1.8% and 66% of patients developing the fracture within 1 year.2 Some causes that might lead to a port fracture and displacement include the type of port used, the site of placement, and the duration of catheter use.2 An endovascular approach is used to retrieve the fractured catheter.3 Knowledge of this complication can help emergency physicians when evaluating a post-chemotherapy patient because catching it early can prevent fatal complications such as cardiac arrhythmias and septic embolization.3

46 ELECTRO-CATHETER EXTRACTION IN JUGULAR ACCESS:METHODS AND TECHNIQUES

Abstract A significant increase of Pacemaker implantation has resulted in an increase in the number of extractions due to the onset of infections and malfunctions. The transvenous leads extraction by means of a dilator sheath can be difficult for possible fibrotic or calcified adhesions and vegetations along the path of the leads. In 90% of cases the firm adhesions are in the superior vena cava-right atrium, of the tricuspid valve ring of the papillary muscles of the right ventricle and in the lead insertion zone. If standard extraction from the implantation site is difficult along the axis subclavian venous-anonymous vena-superior vena cava, due to the presence of tenacious adhesions along the course of the leads, it is necessary to resort to a right internal jugular approach. During the standard extraction there are particularly delicate points like the anonymous trunk and superior vena cava. At this point the sheath is perpendicular to the vein and there is the possibility of vascular injury. Moreover, the twisting of the sheath doesn't permit a favorable approach at the second part of the lead. In fact, it is very difficult that the force applied during the rotation of the sheaths arrives at the tip of the sheath and is not sufficient to win against the adherences. In this case a right internal jugular approach becomes necessary. This method facilitates the lead extraction because the position of the jugular vein is rectilinear with the superior vein cava and the right part of the heart which permits a better and more precise alignment of the sheath with the vein and hearth cavity. The sheath-lead system has a parallel progress at anonymous vein, the superior vein cava and right atrium. This method reduces vascular injury and makes sheath rotation movement more efficient for resection of adherence, furthermore, for large vegetations it is possible to use big sheaths to simplify the resection. The jugular approach involves the introduction from the femoral vein of a pig tale or a deflectable catheter to take the lead into the right atrium making it intravascular. Furthermore, we proceed with the canalization of the jugular vein in sterile method. Then position an introductory 11 Fr by which a lasso catheter will be introduced. The objective is to capture the lead and bring it out of the jugular vein. Then, the operator will apply the sheath-catheter system and given the good position will proceed with the extraction of the lead, by using rotating movements. The entire procedure is done with a fluoroscopy guide with the use of septums to define the field of view only of area of interest and the exposure of the operators. During the important steps such as the capture of the lead by lasso, the use of ad hoc projections, that help the operator in capturing images, is essential to have a clear reference of the position within the atrium of the catheter itself. During the entire procedure, the modulation of the radiant dose is very important, in fact a Low Dose approach can be chosen at first while doses are increased when needed. Radiation protection in these procedures, which can be challenging from a fluoroscopic point of view, is essential. The success of the procedure is the result of skills and experience of all operators engaged: doctors, nurses, and radiology technicians. Figure 1 Use of pigtail to capture the catheter (left); catheter lasso (center); sheath extraction (right)

Surgical Management of Cardiac Masses in Right Atrium Among Bone Sarcoma Pediatric Patients With Totally Implanted Ports.

IntroductionTotally implanted ports (PORTs) have been widely used among patients with malignancy. Cardiac metastasis secondary to bone sarcoma and catheter-related right atrial thrombosis (CRAT) can be both present as cardiac masses. However, these two cardiac masses share very similar imaging characteristics.MethodsThe features, treatments, and outcomes of 5 bone sarcoma pediatric patients with PORTs who suffered from cardiac masses in the right atrium were analyzed. Clinical data and histological characteristics of cardiac masses were also recorded.ResultsAmong 928 patients with malignancy and PORTs, 5 bone sarcoma pediatric patients were found to have cardiac masses in the right atrium. The catheter tips were located in the right atrium of 4 patients and the superior vena cava-right atrium junction (CAJ) of 1 patient. Four patients with good response to anti-tumor treatment had received surgical lumpectomies for pathologic identification and mass excision, with cardiac metastases among 1 patient and thromboses among 3 patients. The median time from venous access port implantation to cardiac mass detection for CRAT was 6.3 months (range: 4.7–6.8 months) and to diagnosis of or possible cardiac metastasis was 13.3 months (range: 11.2–15.4 months).ConclusionThe placement of a catheter tip into the right atrium should be avoided. The time from PORTs implantation to cardiac mass detection might serve as a potential tool to differentiate cardiac metastasis from CRAT. Surgical management may be an effective treatment for bone sarcoma pediatric patients who had good response to anti-tumor treatment and suffered from cardiac masses in the right atrium.

Percutaneous Retrieval of Dislodged Chemo Port Catheter With Inaccessible Tips by a Simplified Technique

Central venous port catheters (CVPCs) are commonly employed for long-term chemotherapy. One of the rare complications associated with CVPCs is catheter fracture and further embolization of the fragmented segment into the heart. The most common site of embolization is the superior vena cava-right atrium (RA) junction. However, infrequently, the catheter may embolize further distally into the right ventricle (RV) and beyond making the fragmented tips difficult to access directly with a snare. Here, we report a case wherein both the catheter tips were lodged in the RV cavity forming a loop in the RA. This necessitated the use of a modified technique to retrieve the fragment percutaneously.

New Insights into Sinus Venosus Defects from Cross-Sectional Imaging

Sinus venosus defects include two varieties, superior and inferior sinus venosus defects. The superior sinus venosus defect is characterized by abnormal communication between two closely related venoatrial structures: 1) the normally positioned superior vena cava-right atrium complex and 2) the right pulmonary vein-left atrium complex that is displaced leftward, forward and upward. Inferior sinus venosus defects primarily involve the inferior vena cava-right atrial junction while the right pulmonary vein-left atrial junction can also be affected. Because of the rarity and wide variation of the defects, the morphological characterization of sinus venosus defects is inconsistent among investigators and often inaccurate. Modern imaging technologies with high spatial and temporal resolutions have allowed accurate and detailed assessment of the pathological anatomy in larger numbers of cases. In this pictorial essay, we revisit the established and controversial features of the sinus venous defects using two-dimensional (2D) and three-dimensional (3D) images obtained by magnetic resonance (MR) or computed tomography (CT) with brief discussion on imaging and treatment strategies.

Location of sinoatrial artery and atria

Abstract Background Clinically manifested injury to the coronary arteries during catheter ablation procedures for atrial arrhythmias is rare. Injury to sinoatrial artery can cause sinus arrest and lead to permanent pacemaker implantation. Previous studies only described the anatomy of the artery but not the relation with atrium. Objective Our study aims to illustrate the course of the sinoatrial artery in relation to the atrium. Methods The images of coronary computed tomography angiography (CCTA) of 110 patients performed from June to September 2019 were reviewed. Results The sinus node was supplied by either single artery (98.18%) or dual blood supply (1.82%). Sinoatrial artery mostly originates from right coronary artery (56.25%), followed by left circumflex artery (42.85) and the aorta (0.90%). When sinoatrial artery originated from right coronary artery or the aorta, it ran medially to the right atrium which its course vertically lied within 0.35±0.51 cm above and 1.45±0.63 cm below the superior vena cava-right atrium junction. The artery then passed between left atrium and right atrium, which 21.88% of the course ran within 0.5 cm from the right upper pulmonary vein ostium. When sinoatrial artery arises from left circumflex artery, 95.83% of this pathing were anterior to left atrial appendage. Only 4.17% went along anteriorly to the left upper pulmonary vein. Most of sinoatrial artery that arises from left circumflex artery (97.92%) ran pass the upper one-third of left atrium, then ran toward posteroseptum of right atrium. This course vertically lied within 0.51±0.73 cm above and 0.67±0.83 cm below the superior vena cava-right atrium junction. Additionally, we found that 39.58% of sinoatrial artery arises from left circumflex artery course lied within 0.5 cm from right upper pulmonary vein ostium. Conclusion Exceeding precaution while performing radiofrequency ablation at anterior upper one-third left atrium, base of left atrium appendage, upper part septal wall of right atrium and right upper pulmonary vein ostium should be established to prevent sinoatrial artery injury. Funding Acknowledgement Type of funding sources: None.

Chest radiography for simplified evaluation of central venous catheter tip positioning for safe and accurate haemodynamic monitoring: a retrospective observational study

ObjectivesThe tip-to-carina (TC) distance on a simple chest X-ray (CXR) has proven value in the determination of correct central venous catheter (CVC) positioning. However, previous studies have mostly focused on...

P1250 Thymoma invading the right atrium - multimodality imaging and its importance for managing and therapeutics

Abstract Introduction Thymoma is the most common primary neoplasm of the anterior mediastinum. Most invasive thymomas are limited to the pericardium. Only few cases of transcaval extension with intracardiac involvement have been reported. Case report We present the case of a 15-year-old boy with previous history of infectious cerebelitis without neurologic sequelae. He presented with interscapular pain for 6 weeks (not improving with symptomatic therapy) and fever for 3 days. On admission, chest radiograph exhibited an opacification in the right hilum (Figure A). He was discharged with antibiotic prescription for presumptive pneumonia. Due to persistence of complaints he was revaluated after 5 days. Signs of superior vena cava (SVC) syndrome were noted. A computerized tomography showed a large soft tissue mass of the anterior mediastinum, in right antero-lateral topography, measuring 12.5x10x9.5 cm with central calcification and extension to the right lung (Figure B). Transthoracic and transoesophageal echocardiography showed an anterior mass compressing the pulmonary artery branch (PA) and SVC with marginal invasion of the right atrium (RA) (Figure C and D). Cardiac MRI confirmed a large mass of the anterior mediastinum with extension and invasion of the right superior lobe, invasion of the superior vena cava with extension into the RA (Figure E). Transthoracic core-needle biopsy was performed and histopathological diagnosis confirmed an invasive thymoma. The case was discussed at joint cardiothoracic surgery and oncology multidisciplinary meeting and it was agreed to neoadjuvant chemotherapy regimen followed by surgery. Intraoperatively, a large tumor invading the SVC and proximal RA was found, in accordance with the echocardiographic and MRI findings. Due to unforeseen metastatic implants on the adventitia of the main PA and ascending aorta, resection of the tumor was not performed. Palliative decompression of the venous system was performed with interposition of a ringed vascular prosthesis between the left brachiocephalic vein and the right atrial appendage. (Figure F). The patient received postoperative radiotherapy and is asymptomatic without signs of SVC syndrome for 3 months. Discussion and conclusion This report illustrates a rare case of an invasive thymoma with extension to cardiac structures. Multimodality imaging for quality decision-making was imperative in the management and for surgical planning of this case. Transthoracic and transoesophageal echocardiography remain the exams of choice for the diagnosis of intracardiac disease. As demonstrated, a high index of suspicion is needed because clinical symptoms are unspecific and late diagnosis of potentially resectable tumors are associated with a poor prognosis. Abstract P1250 Figure. Multimodality imaging

Pediatric central venous catheterization: The Role of the Aortic Valve in Defining the Superior Vena Cava-Right Atrium Junction.

The aortic valve (AV) has been used as a surrogate marker for the superior vena cava-right atrium (SVC-RA) junction during the placement of central venous catheters. There is a paucity of evidence to determine whether this is a consistent finding in children. Eighty-seven computed tomography scans of the thorax acquired at local children's hospitals from April 2010 to September 2011 were retrospectively collected. The distance between the SVC-RA junction and the AV was measured by dual consensus. The cranio-caudal level of the junction and the AV were referenced to the costal cartilages (CCs) and anterior intercostal spaces (ICSs). The results confirmed that the SVC-RA junction has a variable relationship to the AV. The junction was on average 3.1 mm superior to the AV. This distance increased with age. In the <1-year-old age group, the junction was on average 1.3 mm superior to the AV (range: -6 to 11 mm). In the 1-2 years old age group: 3.5 mm (range: -8 to 15 mm). In the 3-6 years old: 3.8 mm (range: -9 to 13 mm). In the >7 years old age group: 4 mm (range: -11 to 16 mm). The surface anatomy of the SVC-RA junction was variable, ranging from the second ICS to sixth CC. The SVC-RA junction has a predictable relationship to the AV, and this can be used as an adjunct marker for accurate placement of central venous catheters except in the smallest neonates. Clin. Anat. 32:778-782, 2019. © 2019 Wiley Periodicals, Inc.

Percutaneous transvenous retrieval of fractured catheter in cancer patients receiving chemotherapy.

To explore the clinical efficacy and safety of percutaneous transvenous retrieval of intravascular fractured catheter and to evaluate the possible reasons and final results in cancer patients. A dataset of 19 patients was used. Percutaneous transvenous retrieval of intravascular fractured catheter was performed in each patients. Clinical data was retrospectively analyzed with respect to the efficacy, safety and outcome, and chest radiography was performed to verify that no catheter fragments were left. Two cases had peripherally inserted central catheter and 17 had subcutaneous implanted port catheter. The catheter fragments were located in the brachiocephalic vein-superior vena cava (n = 1), superior vena cava (n = 1), superior and inferior vena cava (n = 1), superior vena cava-right atrium (n = 2), brachiocephalic vein-superior vena cava-right atrium (n = 1), superior vena cava-right atrium-right ventricle (n = 6), brachiocephalic vein-superior vena cava-right atrium and right ventricle (n = 1) and pulmonary artery (n = 6), respectively. All of these catheter fragments were retrieved successfully. No complications such as bleeding and thrombosis were found. Percutaneous transvenous retrieval is a safe, minimally invasive and relatively simple procedure for the patients with fractured catheter and should be recommended as the first choice.

Electrocardiographic-Guided Technique for Placement of Ventriculoatrial Shunts: A Valid and Cost-Effective Technical Simplification.

Ventriculoatrial (VA) shunt is a routine technique for the treatment of hydrocephalus. The correct position at the superior vena cava-right atrium junction is generally assessed by radiography. We present the first experience of an alternative, nonradiographic technique to assess the distal end of the VA shunts through an electrocardiographic (EKG) method. The technique has developed from the large experience of central venous catheters (CVC) worldwide; the EKG-guided method is a common and validated alternative to standard radiologic control of the location of the tip of any CVC. Five consecutive patients underwent VA shunt with venous catheter positioned with the EKG-guided technique. The position of the catheter tip was verified by standard chest radiography. Four men and 1 woman (mean age, 45.4 years) underwent VA shunt for hydrocephalus with the EKG-guided technique. The side of internal jugular vein puncture was the right side in 4 cases and the left side in 1 case. As confirmed by radiography, all VA shunt tips were located within the correct range. There was no radiologic evidence of procedure-related complication or catheters that had to be replaced. The EKG-guided technique for VA shunts is as accurate as fluoroscopy, but simpler, more readily available, less expensive, safer, and more cost effective. It reduces the need of radiography and radiologic exposition for both patients and operators. The EKG method may be a valid and cost-effective alternative to standard radiologic control in VA shunts, as for any central venous access device, and could become the preferential method for confirming tip position during VA shunt surgery.

Prediction of the optimal depth for superior vena cava cannulae with cardiac computed tomography during minimally invasive cardiac surgery: a prospective observational cohort study

BackgroundThe determination of the adequate depth of superior vena cava cannulae during minimally invasive cardiac surgery is important for warranting venous drainage and preventing complications during cardiopulmonary bypass. We investigated whether preoperative cardiac computed tomography might be useful for predicting the optimal depth of superior vena cava cannulae.MethodsThe patients who required superior vena cava cannulation and had cardiac tomographic image among those scheduled to undergo a minimally invasive cardiac surgery were evaluated. The distance between the upper border of the clavicular sternal head and the superior vena cava-right atrium junction was measured on cardiac computed tomography. Equivalence test for the difference between the distance measured on cardiac computed tomography and the distance verified by surgeon’s direct inspection in the surgical field was performed. The range −1 cm to 1 cm was predefined as an equivalence region. In addition, the distances between the upper border of the clavicular sternal head and the carina level on chest radiography were measured to compare the relative position of carina with regard to the superior vena cava-right atrium junction.ResultsA total of 46 patients were evaluated. The distance from the upper border of the clavicular sternal head to the superior vena cava-right atrium junction measured on cardiac computed tomography and the distance verified by surgeon’s inspection was equivalent, with the 95% confidence interval for the mean difference within the equivalence region (0.05–0.52, P < 0.0001). The carina level on chest radiography was found at least 2 cm above the superior vena cava-right atrium junction in all patients.ConclusionsPreoperative cardiac computed tomography might be valuable for predicting the adequate depth of superior vena cava cannulae. Additionally, the carina on chest radiography might indicate a useful landmark for proper position of central venous catheter.Trial registrationThis study has been registered at Clinical Research Information Service on 6 July 2012 (KCT0000477).

Confirmation of optimal guidewire length for central venous catheter placement using transesophageal echocardiography

Study objectiveSeveral authors have reported rare, but severe, complications associated with the length of the intravascular guidewire during central venous catheter placement, as the wire tip can cause cardiac arrhythmia or perforation or become trapped within the vessel. Although one report investigated the optimal guidewire length using fluoroscopy, few reports have precisely measured guidewire position using transesophageal echocardiography (TEE). Here, we investigated the appropriate intravascular length of a guidewire for right internal jugular vein approach using TEE during cardiac surgery. DesignA prospective observational study. SettingOperating room. PatientsFifty-two patients undergoing elective cardiac surgery. MeasurementsThe intravascular guidewire distance from the insertion site to the superior vena cava–right atrium (SVC-RA) junction was measured by TEE. Demographic factors (height, weight, age, etc) were recorded. ResultsThe mean distance from the access site to the SVC-RA junction was 17.8±1.3 cm (maximum/minimum =20.0/15.0 cm). There was a greater correlation with height than with weight or age. ConclusionWe confirmed the wire tips at all cases by ultrasonography. The distance using TEE was similar to that by fluoroscopy, but TEE was more precise. Guidewire length was weakly correlated to height. About 15 cm as minimum length should be considered the limit for guidewire length in an adult, in consideration of height, to ensure patient safety during central catheter placement for right internal jugular vein approach.

A comparative study of two techniques (electrocardiogram- and landmark-guided) for correct depth of the central venous catheter placement in paediatric patients undergoing elective cardiovascular surgery.

Background and Aims:The complications of central venous catheterisation can be minimized by ensuring catheter tip placement just above the superior vena cava-right atrium junction. We aimed to compare two methods, using an electrocardiogram (ECG) or landmark as guides, for assessing correct depth of central venous catheter (CVC) placement.Methods:In a prospective randomised study of sixty patients of <12 years of age, thirty patients each were allotted randomly to two groups (ECG and landmark). After induction, central venous catheterisation was performed by either of the two techniques and position of CVC tip was compared in post-operative chest X-ray with respect to carina. Unpaired t-test was used for quantitative data and Chi-square test was used for qualitative data.Results:In ECG group, positions of CVC tip were above carina in 12, at carina in 9 and below carina in 9 patients. In landmark group, the positions of CVC tips were above carina in 10, at carina in 4 and below carina in 16 patients. Mean distance of CVC tip in ECG group was 0.34 ± 0.23 cm and 0.66 ± 0.35 cm in landmark group (P = 0.0001). Complications occurred in one patient in ECG group and in nine patients in landmark group (P = 0.0056).Conclusion:Overall, landmark-guided technique was comparable with ECG technique. ECG-guided technique was more precise for CVC tip placement closer to carina. The incidence of complications was more in the landmark group.

Simple Formula to Place Central Venous Catheter Tip at T6 After Surgical Cutdown in Neonates

The objective of this paper was to develop a generally applicable formula to estimate correct catheter length after surgical cutdown in right internal jugular vein (RIJV) in neonates. The carina has been utilized as an anatomic landmark indicating superior vena cava-right atrium junction (SVC-RA) for the optimal placement of the central venous catheter (CVC) tip position. However, this landmark may not be accurate in neonates. Recent researches noted that the sixth vertebral body (T6) could better serve as a new landmark of SVC-RA in neonates and smaller children. We prospectively performed RIJV cutdown. For a controlled and reproducible surgical procedure, the venous entry site was consistently taken as the point where the omohyoid muscle crosses the RIJV. On intraoperative infantogram, the vertical distance between the venous entry site and T6 was measured and the catheter was inserted to this length. A linear regression model was investigated using the following variables to elicit the best prediction model for catheter length: gestational age, postconceptional age, birth weight, and weight at operation. Weight at operation best correlated with the measured CVC length (R2 = 0.916, P = 0.00), and the following linear equation was derived: estimated CVC length (mm) = 9 × [weight at operation (Kg)] + 30. There was no statistically significant difference between measured and estimated CVC length. With this formula, the optimal catheter length could easily be estimated when considering RIJV cutdown.

Feasibility of creating a novel animal heart model to test transcatheter techniques for a cavocaval connection that mimics a Fontan completion

The objective of this study was to create a novel animal model to foster the future development of interventional techniques for a cavocaval connection that mimics a Fontan completion. Ten sheep were studied. All had the superior vena cava-right atrium junction closed using a polytetrafluoroethylene membrane. A valveless Gore-Tex conduit connecting the terminal portion of the superior vena cava to the right atrium was used to bypass the polytetrafluoroethylene occlusion and to allow normal venous drainage through the right atrium. Radio-opaque nitinol rings were placed around the inferior vena cava near its entry in the right atrium to allow better fluoroscopic visualization and to enhance stent stability during transcatheter cavocaval connection. The first 3 animals died during the learning curve as a result of technical issues. The subsequent 7 surviving sheep showed good flow dynamics on cardiac catheterization. Transcatheter cavocaval connection was performed successfully performed in 6 sheep at 0 to 9 months after the initial surgery. Sacrifice was done electively in all animals at 1 to 9 months per protocol. One animal was euthanized early because of an untreatable infection. One sheep was observed as a control without a transcatheter cavocaval connection and was sacrificed at 12 months. A novel, chronic ovine model to foster development of transcatheter techniques for cavocaval connection to mimic a Fontan completion was created. The successful model is easily reproducible after a short learning curve and shows good survival.