Supported in part by Magnetecs Inc. (Inglewood, California, USA) in collaboration with the Comunidad de Madrid and La Paz University Hospital. We thank Iv&aacute;n Filgueiras-Rama and Jaime Palomo-Cousido for their help in the illustration of the figures and video editing.

Patients who underwent ablation of a right or left atrium flutter substrate were included (Table 1). The presence of decompensated or severe systemic disease, thrombus within the left atrium, renal failure, age &lt;18 years, body mass index &gt;40 and pregnancy were the exclusion criteria. This protocol is part of the initial safety and feasibility protocol approved by the Institution Research and Ethics Committee. No atrial fibrillation procedures were included in this protocol. All patients gave informed consent. 
1. Description of the Robotic Magnetic Navigation System
The Catheter Guidance Control and Imaging (CGCI) system employs eight powerful electromagnets to produce a highly agile magnetic field (to 0.16 Tesla) within an effective control area optimized to focus and contain the magnetic field almost entirely within the magnetic chamber. The magnetic chamber operates silently, has no moving parts and cools the electromagnet coils with non-toxic mineral oil. Current-regulated amplifiers provide the power to the magnetic chamber coils. The system produces magnetic fields 10 to 20 times less in intensity than Magnetic Resonance Imaging and no magnetic fields are generated when it is not in magnetic guidance mode. The magnetic field generators provide torque and force for moving, positioning and directing the tip of a catheter equipped with three permanent magnet pellets attached to its distal end. 
The Robotic system includes an Operation Console, the CGCI Controller computer and a motorized linear catheter advancement mechanism. The system uses a standard 3-axis joystick, which is used to rotate the magnetic field and manually advance or retract the catheter. A 3D Controller is used to push the catheter in any screen-oriented direction. The X-Ray C-Arm may be rotated or extracted at the Operation Console using the X-Ray Dialog. The Operation Console unifies the display of the CGCI system, electroanatomical mapping system, EP recording system, intracardiac ultrasound (ICE), and X-Ray. It allows the direct keyboard and mouse control over the electroanatomical mapping system and EP recording system. Typically, the center screen is used for the electroanatomical mapping system screen and the CGCI overlay graphics. 
2. Patient's Preparation
 Admit the patient to the hospital the same day or the day before the procedure. Overnight fasting state is required. 
<ol>
 <li>Position the patient on the operation table, where the nursing staff cannulates a peripheral intravenous catheter before the procedure.</li>
 <li>Outside of the magnetic chamber, the medical staff obtains right and left vein femoral access under local anesthesia with lidocaine. Place sheath introducers into the right and left femoral veins. We recommend guiding left atrium substrates using intracardiac echocardiography, which probe is introduced through a 9 French (Fr) left femoral vein sheath and positioned into the right atrium. </li>
 <li>For left atrium substrates, administer an initial intravenous bolus and repeated doses of heparin to maintain an activated clotting time of 250-300 s.</li>
 <li>Administer an initial bolus of 2 mg of midazolam followed by continuous intravenous propofol sedation and intermittent intravenous bolus of morphine hydrochloride during the procedure. </li>
</ol>
3. Conventional Electrophysiological Study
<ol>
 <li>Position standard catheters through the femoral sheath introducers into the right cardiac chambers for conventional diagnostic electrophysiological study. Use fluoroscopy guidance during manually positioning.</li>
 <li>Position a decapolar catheter into the coronary sinus and a screw-in catheter in the right atrial septum. </li>
 <li>Introduce a special steerable sheath with 3 electrodes along its distal end through the right femoral vein (Figure 1A) and place it in the inferior vena cava or the lower right atrium. </li>
 <li>Introduce a 7 Fr magnetized catheter into the cardiac chambers through the special sheath (Figure 1A, 1B). Next, perform conventional work up of the arrhythmia mechanism. </li>
 <li>If necessary (e.g. left atrium flutter mechanism), trans-septal access to the left atrium is achieved using a trans-septal sheath and continuous ICE monitoring. For left atrial flutter procedures also place a multipolar catheter into the left atrium through the trans-septal puncture. </li>
</ol>
4. Preparing for Remote Navigation. Catheter, Sheath, and Catheter Advancement Mechanism Assembly 
<ol>
 <li>The motorized linear catheter advancement mechanism consists of a sterilizable wheel drive gearbox and a motor base. It also includes a disposable sheath clip and leg mount (Figure 2A). The device adds or removes catheter slack.</li>
 <li>Mount the sheath in the clip and insert the catheter into the sheath, and manually advance it into the right/left atrium. The latter is confirmed by the mapping system and fluoroscopy. For left atrial substrates position the sheath in the right atrium in close proximity to the interatrial septum.</li>
 <li>Next, place catheter's shaft between the rollers of the wheel drive gearbox by pulling back on the thumb lever.</li>
 <li>The X-Ray C-Arm is moved to its operational position within the magnetic chamber. Patient's table is now advanced to localize the thorax within the magnetic field. </li>
 <li>The operator leaves the operation room and takes control from the operation console. </li>
 <li>The Magnetic catheter and the special sheath with electrodes are now shown on the center screen. All CGCI and electroanatomical mapping system operational functions are available at the CGCI operation Console.</li>
</ol>
 5. Remote Navigation and Mapping 
<ol>
 <li>Perform catheter contact calibration of the electrical coupling index system. Maximum and minimum contact values are set up on the control panel.</li>
 <li>Full integration with the electroanatomical mapping system and a closed-loop servo system allow remote navigation and 3D geometrical reconstruction of the right/left cardiac chambers, which allows the procedure to continue with minimal X-ray exposure. </li>
 <li>Use a right hand 3D Controller to steer the catheter to specific sites within the right/left atrium by changing the direction of the magnetic field (Figure 2B). A yellow magnetic arrow indicates the direction of the magnetic field. Use a left hand 3-axis joystick to control the amount of catheter slack (Figure 2C). The motorized device placed at the patient's leg allows the addition and retraction of catheter slack (Figure 2A). </li>
 <li>Rapid changes in the magnetic field magnitude, direction, and gradient yield push/pull and/or torque (bend) movements in the distal portion of the catheter. Real-time remote navigation is assessed based on field vector adjustments and subsequent response in the tip of the catheter. A magnetic icon displays the coil power values as colors. Green indicates a strong positive field, and red indicates a strong negative field (Figure 3). </li>
 <li>The catheter tip is aligned parallel to the vector direction of the magnetic flux density. The magnetic field gradient generated for force control of the catheter is up to 0.7T/meter, with a maximal perpendicular force exerted of 25 g. </li>
 <li>Perform geometrical point acquisitions from the 4 poles of the magnetized catheter while slowly moving the catheter all around the atrial chambers. A 3D EAM reconstruction can be obtained after few minutes (Figure 3A, 3B).</li>
 <li>Remote navigation with the steerable sheath positioned in the right atrium allows reaching the right inferior pulmonary vein by either directly deflecting the catheter upon crossing the interatrial septum or after making a loop in the opposite wall and then pointing the catheter towards the right inferior pulmonary vein. </li>
 <li>Generate activation, voltage and first post-pacing interval maps to characterize the reentrant circuit (Figure 4A, 4B). Identify ablation targets and localize them on the 3D geometry. </li>
</ol>
6. Ablation. Manual and Automated Catheter Positioning in the Target Sites
<ol>
 <li>In Automated Magnetic Guidance mode, the operator can automatically guide the catheter to specific targets by double-clicking on an electroanatomical mapping system label. This represents an essential feature to create remote and automatic ablation lines. </li>
 <li>For each individual target and with the CGCI system operating in the automated mode, drive the catheter to the target points (Figure 4C). In Automated mode, the system displays a targeting dialog. This indicates the intended target, range, time and targeting search status.</li>
 <li>Accuracy to automatically position the catheter on the target is also measured by the distance of the final location of the catheter to the initial manual positioning. The distance is measured in mm and considered significant if larger than 3 mm. Catheter navigation accuracy requires using the field-scaling tool of the electroanatomical mapping system. </li>
 <li>Manual intervention of an automatic search is possible by using the joystick or 3D Controller. </li>
 <li>To terminate the arrhythmia deliver radiofrequency energy to specific sites labeled as target points, either manually or automatically guided. The arrhythmia terminates and sinus rhythm is restored upon interruption of the reentrant circuit (Figure 4C, 4D). No re-induction by fast atrial pacing confirms the elimination of the arrhythmia. </li>
</ol>
The safety of the CGCI system is evaluated for each one of the experimental steps.

<ol>
	<li>Evans, G. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Percutaneous+Cardiac+Mapping+and+Ablation+Registry:+final+summary+of+results.">The Percutaneous Cardiac Mapping and Ablation Registry: final summary of results.</a> Pacing Clin. Electrophysiol. 11, 1621-1626 (1988).</li><li>Cappato, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Updated+worldwide+survey+on+the+methods,+efficacy,+and+safety+of+catheter+ablation+for+human+atrial+fibrillation.">Updated worldwide survey on the methods, efficacy, and safety of catheter ablation for human atrial fibrillation.</a> Circ. Arrhythm. Electrophysiol. 3, 32-38 (2010).</li><li>Lafuente-Lafuente, C., Mouly, S., Longas-Tejero, M. A., Mahe, I., Bergmann, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antiarrhythmic+drugs+for+maintaining+sinus+rhythm+after+cardioversion+of+atrial+fibrillation:+a+systematic+review+of+randomized+controlled+trials.">Antiarrhythmic drugs for maintaining sinus rhythm after cardioversion of atrial fibrillation: a systematic review of randomized controlled trials.</a> Arch. Intern. Med. 166, 719-728 (2006).</li><li>Reddy, V. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Catheter+ablation+of+atrial+fibrillation+without+the+use+of+fluoroscopy.">Catheter ablation of atrial fibrillation without the use of fluoroscopy.</a> Heart Rhythm. 7, 1644-1653 (2010).</li><li>Knackstedt, C., Schauerte, P., Kirchhof, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electro-anatomic+mapping+systems+in+arrhythmias.">Electro-anatomic mapping systems in arrhythmias.</a> Europace. 10, iii28-iii34 (2008).</li><li>Merino, J. L., Guzman, G., Fernandez-Cuadrado, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atrial+fibrillation+ablation+guided+by+computed+tomography.">Atrial fibrillation ablation guided by computed tomography.</a> Rev. Esp. Cardiol. 62, 13133308 (2009).</li><li>Merino, J. L., Refoyo, E., Peinado, R., Cuesta, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Real-time+representation+of+multielectrode+ablation+catheters+by+integration+of+computed+tomographic+geometry+with+three-dimensional+electroanatomic+mapping+of+left+atrium+and+pulmonary+veins.">Real-time representation of multielectrode ablation catheters by integration of computed tomographic geometry with three-dimensional electroanatomic mapping of left atrium and pulmonary veins.</a> Heart Rhythm. 5, 628-629 (2008).</li><li>Piorkowski, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Computed+tomography+model-based+treatment+of+atrial+fibrillation+and+atrial+macro-re-entrant+tachycardia.">Computed tomography model-based treatment of atrial fibrillation and atrial macro-re-entrant tachycardia.</a> Europace. 10, 939-948 (2008).</li><li>Ernst, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+and+robotic+navigation+for+catheter+ablation:+"joystick+ablation".">Magnetic and robotic navigation for catheter ablation: "joystick ablation".</a> J. Interv. Card. Electrophysiol. 23, 41-44 (2008).</li><li>Nguyen, B. L., Merino, J. L., Gang, E. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Remote+Navigation+for+Ablation+Procedures+-+A+New+Step+Forward+in+the+Treatment+of+Cardiac+Arrhythmias.">Remote Navigation for Ablation Procedures - A New Step Forward in the Treatment of Cardiac Arrhythmias.</a> European Cardiology. 6, 50-56 (2010).</li><li>Schmidt, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Remote+navigation+systems+in+electrophysiology.">Remote navigation systems in electrophysiology.</a> Europace. 10, iii57-iii61 (2008).</li><li>Al-Ahmad, A., Grossman, J. D., Wang, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+experience+with+a+computerized+robotically+controlled+catheter+system.">Early experience with a computerized robotically controlled catheter system.</a> J. Interv. Card. Electrophysiol. 12 (3), 199-202 (2005).</li><li>Ray, I. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Initial+experience+with+a+novel+remote-guided+magnetic+catheter+navigation+system+for+left+ventricular+scar+mapping+and+ablation+in+a+porcine+model+of+healed+myocardial+infarction.">Initial experience with a novel remote-guided magnetic catheter navigation system for left ventricular scar mapping and ablation in a porcine model of healed myocardial infarction.</a> J. Cardiovasc. Electrophysiol. 18, 520-525 (2007).</li><li>Ernst, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Initial+experience+with+remote+catheter+ablation+using+a+novel+magnetic+navigation+system:+magnetic+remote+catheter+ablation.">Initial experience with remote catheter ablation using a novel magnetic navigation system: magnetic remote catheter ablation.</a> Circulation. 109, 1472-1475 (2004).</li><li>Nguyen, B. L., Farkas, L., Marx, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Heart Rhythm Society's 30th Annual Scientific Sessions. , (2009).</li><li>Nguyen, B. L., Merino, J. L., Gang, E. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Remote+Navigation+for+Ablation+Procedures+-+A+New+Step+Forward+in+the+Treatment+of+Cardiac+Arrhythmias.">Remote Navigation for Ablation Procedures - A New Step Forward in the Treatment of Cardiac Arrhythmias.</a> European Cardiology. 6, 50-56 (2010).</li><li>Gang, E. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamically+shaped+magnetic+fields:+initial+animal+validation+of+a+new+remote+electrophysiology+catheter+guidance+and+control+system.">Dynamically shaped magnetic fields: initial animal validation of a new remote electrophysiology catheter guidance and control system.</a> Circ. Arrhythm. Electrophysiol. 4, 770-777 (2011).</li><li>Bernabei, M. A., Ugarte, R. C., Martin, D. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Heart Rhythm Society's 30th Annual Scientific Sessions. , (2009).</li><li>Saliba, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atrial+fibrillation+ablation+using+a+robotic+catheter+remote+control+system:+initial+human+experience+and+long-term+follow-up+results.">Atrial fibrillation ablation using a robotic catheter remote control system: initial human experience and long-term follow-up results.</a> J. Am. Coll. Cardiol. 51, 2407-2411 (2008).</li><li>Hlivak, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Robotic+navigation+in+catheter+ablation+for+paroxysmal+atrial+fibrillation:+midterm+efficacy+and+predictors+of+postablation+arrhythmia+recurrences.">Robotic navigation in catheter ablation for paroxysmal atrial fibrillation: midterm efficacy and predictors of postablation arrhythmia recurrences.</a> J. Cardiovasc. Electrophysiol. 22, 534-540 (2011).</li></ol>

Dr. Jos&eacute; L. Merino received grants for clinical research from Magnetecs Inc. and Boston Scientific. Dr. Jos&eacute; L. Merino served as a speaker for St. Jude Medical. Dr. Gang and Yehoshua Shachar have equity interest in Magnetecs Corp.

This is the first clinical report using the CGCI remote navigation system. It shows important technical features that might facilitate both navigation and ablation in right and left atrial substrates. The system may potentially overcome some of the limitations of the former magnetic-based Niobe system.10 Thus, endocardial contact force and navigation inside the cardiac chambers may substantially improve by increasing the strength of the magnetic field magnitude up to 0.16 Tesla compared with 0.08 Tesla in the Niobe system. Continuous and rapid shaping and reshaping of the magnetic field, rather than moving external magnets to change the magnetic field,13,14 provides instantaneously transmitted changes to the tip of the magnetized catheter leading to almost real&#x2010;time remote navigation. In automated mode the CGCI system also provides a true closed-loop servo system that has the ability to keep the catheter tip on a desired anatomic target by continuously adjusting the direction and intensity of the magnetic fields.17 
The Sensei system, based on steerable sheaths manipulated within the heart by a mechanical robotic arm, allows real-time catheter movements.12 However, the use of mechanical forces to drive the catheter does not represent a technological advance over manual manipulation. Initial reports using the Sensei system had raised the concern of higher rate of cardiac tamponade than conventional manual radiofrequency delivery,18,19 which might have been related to remote manipulation of the stiff steerable Artisan catheter (Hansen Medical, Mountain View, CA, USA). Further experience and introduction of a special feature of the system to indirectly estimate catheter contact force on the tissue (IntelliSense) have shown that tamponade rates are not superior to conventional manual approach and may be more related to different temperature and power radiofrequency settings.20 
The CGCI system does not require a lab with specific magnetic isolation since the magnetic field is highly focused on patient&#x2019;s torso. In addition, the electrophysiology room can be used either as a conventional electrophysiology lab or as a magnetic lab by moving patient's table from its regular position towards the magnetic chamber. The latter can be done either manually or by remote control. Although no major complications have been present in this initial experience, in case of serious complications, such as pericardial effusion and tamponade, it would be possible to remove the patient from the magnetic chamber in &asymp;15 sec.
General demerits such as lack of real-time contact force monitoring or lesion visualization still apply to the CGCI system. Combining robotic navigation with real-time contact force catheters and direct visualization of the atrial cavities may be a future feasible approach to increase long-term success of ablation lesions and decrease the risk of complications. To date, experimental data using the CGCI system in pigs have demonstrated reproducible navigation and accurate and rapid catheter positioning on the selected ablation targets within the atrial chambers.17 Once the ablation target is localized, the system has the ability to navigate the catheter tip to the selected target despite the cardiac motion and anatomical irregularities. Furthermore, necropsy studies in the same animals revealed that the majority of radiofrequency lesions were transmural.17 In this first report in humans the system also shows reproducible navigation and accurate and rapid catheter positioning on the selected ablation targets within the right or left atrial chambers. The use of rapid magnetic field adjustments might enhance catheter tip stability and result in fewer radiofrequency applications as well as fewer major complications. Although the results and follow up in this initial experience are encouraging, future large and randomized clinical trials in patients undergoing complex catheter-guided ablation procedures are needed to demonstrate these potential benefits.

Catheter ablation of cardiac arrhythmias has become an effective treatment for different types of cardiac arrhythmias.1,2 Antiarrhythmic drugs have limited efficacy and often need to be withdrawn due to secondary effects or pro-arrhythmia.3 Thus, ablation is the only chance for a definitive treatment in many patients. Ablation procedures require moving catheters inside the vascular system and cardiac chambers to further identify the arrhythmia substrate before ablation. Proper catheter manipulation requires a skilled electrophysiologist working under fluoroscopic guidance. This may result in significant X-ray exposure, which is a risk for both patients and medical staff. In the last two decades, different navigation systems able to create electro-anatomical maps (EAM) have led to a decrease in X-ray exposure4 and to a better understanding of the substrate of cardiac arrhythmias.5-8 However, moving and placing catheters into specific regions of the heart still requires manual guidance, which makes these procedures highly dependent on operator skills. In addition, the constant beating of the heart makes stability one of the main problems of radiofrequency delivery in certain target cardiac regions. New remote navigation systems have been recently developed with the objective of overcoming such limitations and allowing the operators to be away from the X-ray source while they are moving the catheters inside the cardiovascular system.9-11 Two remote navigation systems are currently commercially available; the robotic catheter control system (Sensei system, Hansen Medical)12 and the magnetic catheter navigation system (Niobe system, Stereotaxis).13,14 The former is based on two steerable sheaths, through which any conventional catheter can be introduced for further manipulation via a pull-wire mechanism by a robotic arm fixed at a standard fluoroscopy table. The second system is based on two permanent magnets positioned on each side of the patient's body to create a uniform magnetic field. Special catheters with magnets affixed to their distal end can be navigated within the cardiac chambers by changing the orientation of the external magnetic fields. Shortcomings such as safety and similar to manual navigation or weak tissue contact force and lack of real time catheter response are present in Sensei and Niobe, respectively. 
In this report, we describe the features and potential ablation capabilities of a recently developed navigation system, the Catheter Guidance, Control and Imaging (CGCI).15,16

<table border="1">
<tbody>
 <tr>
 <td>Name of Reagent/ Equipment</td>
 <td>Company</td>
 <td>Catalog Number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>Radiofocus Introducer II 7 Fr.</td>
 <td>Terumo</td>
 <td>RS*R70N10MQ</td>
 <td></td>
 </tr>
 <tr>
 <td>Radiofocus Introducer II 6 Fr.</td>
 <td>Terumo</td>
 <td>RS*R60N10MQ</td>
 <td></td>
 </tr>
 <tr>
 <td>Avanti+ Introducer 9 Fr.</td>
 <td>Cordis, Johnson &amp; Johnson</td>
 <td>504-609X</td>
 <td></td>
 </tr>
 <tr>
 <td>Pecutaneous Transeptal Catheter Introducer Set 8 Fr.</td>
 <td>Medtronic</td>
 <td>008591</td>
 <td></td>
 </tr>
 <tr>
 <td>Brockenbrough Curved Needle</td>
 <td>Medtronic</td>
 <td>003994</td>
 <td></td>
 </tr>
 <tr>
 <td>Percutaneuos Transeptal Catheter Introducer Agilis ES</td>
 <td>St. Jude Medical</td>
 <td>3271521</td>
 <td></td>
 </tr>
 <tr>
 <td>BRK Transeptal Curved Needle</td>
 <td>St. Jude Medical</td>
 <td>407205;</td>
 <td></td>
 </tr>
 <tr>
 <td>Extension Set</td>
 <td>Sendal</td>
 <td>L-303/100</td>
 <td></td>
 </tr>
 <tr>
 <td>Extension Tube (25 cm)</td>
 <td>Iberhospitex S.A</td>
 <td>0044402</td>
 <td></td>
 </tr>
 <tr>
 <td>BD Eclipse Needle 25G x 5/8 (0.5 mm x 16 mm)</td>
 <td>BD</td>
 <td>305760</td>
 <td></td>
 </tr>
 <tr>
 <td>BD Eclipse Needle 21G x 1 1/2 TW (0.8 mm x 40 mm)</td>
 <td>BD</td>
 <td>305895</td>
 <td></td>
 </tr>
 <tr>
 <td>Surgical Gloves Sterile</td>
 <td>Semperit Technische Produkte Gesellschaft m. b. H. Division Sempermed</td>
 <td>826054720</td>
 <td></td>
 </tr>
 <tr>
 <td>Adult Cannula with 2.1 m Tubing</td>
 <td>Wolfram Droh GmbH</td>
 <td>MDRNC-03N</td>
 <td></td>
 </tr>
 <tr>
 <td>Oxygen Mask</td>
 <td>Carburos Medica Grupo Air Products</td>
 <td>75098</td>
 <td></td>
 </tr>
 <tr>
 <td>Saline</td>
 <td>Baxter S.L.</td>
 <td>PE1324</td>
 <td></td>
 </tr>
 <tr>
 <td>Saline </td>
 <td>Laboratorios Grifols</td>
 <td>3033986</td>
 <td></td>
 </tr>
 <tr>
 <td>Sterile Disposable Scalpel</td>
 <td>Sovereign </td>
 <td>D16390</td>
 <td></td>
 </tr>
 <tr>
 <td>I.V. Set for Gravity Infusion</td>
 <td>Sendal</td>
 <td>NT-820-ELL180</td>
 <td></td>
 </tr>
 <tr>
 <td>Sterile Banded Bag</td>
 <td>Barrier</td>
 <td>705845</td>
 <td></td>
 </tr>
 <tr>
 <td>Sterile Gauzes</td>
 <td>Ortopedia y Cirug&iacute;a, S.L.</td>
 <td>0323</td>
 <td></td>
 </tr>
 <tr>
 <td>Sterile Syringe</td>
 <td>BD Plastipak</td>
 <td>302188</td>
 <td></td>
 </tr>
 <tr>
 <td>Infusion Set. Anti-Siphon Valve 15 &mu;m Filter</td>
 <td>Alaris</td>
 <td>273-002</td>
 <td></td>
 </tr>
 <tr>
 <td>Infusion Pump (x4)</td>
 <td>CardinalHealth</td>
 <td>25042ESD1</td>
 <td></td>
 </tr>
 <tr>
 <td>Povidone-iodine (antiseptic for topical application) </td>
 <td>Lainco, S.A.</td>
 <td>619791.2 EFP</td>
 <td></td>
 </tr>
 <tr>
 <td>Morfine Hydrochloride 1%</td>
 <td>B. Braun</td>
 <td>451062</td>
 <td></td>
 </tr>
 <tr>
 <td>Propofol </td>
 <td>Fresenius Kani</td>
 <td>600514</td>
 <td></td>
 </tr>
 <tr>
 <td>Heparin</td>
 <td>Hospira Productos Farmac&eacute;uticos y Hospitalarios, S.L.</td>
 <td>Q63004</td>
 <td></td>
 </tr>
 <tr>
 <td>Lidocaine 1%</td>
 <td>B. Braun</td>
 <td>645598</td>
 <td></td>
 </tr>
 <tr>
 <td>Midazolam</td>
 <td>B. Braun</td>
 <td>602567</td>
 <td></td>
 </tr>
 <tr>
 <td>Iodixanol Injection 320 mgI/mL</td>
 <td>GE Healthcare</td>
 <td>687251.2</td>
 <td></td>
 </tr>
 <tr>
 <td>Pre-gelled Electrosurgical Plate</td>
 <td>Blayco</td>
 <td>2125-5</td>
 <td></td>
 </tr>
 <tr>
 <td>Single Patient Use ECG Electrodes</td>
 <td>Ambu</td>
 <td>SP-00-S/50</td>
 <td></td>
 </tr>
 <tr>
 <td>Irrigated Magnetic Navigation Catheter MagnoFlush Gold Tip 4 mm.</td>
 <td>MedFact Engineering GmbH</td>
 <td>100-002</td>
 <td></td>
 </tr>
 <tr>
 <td>Screw-in Catheter. Temporary Transcenous Pacing Lead System</td>
 <td>Medtronic</td>
 <td>6416-200</td>
 <td></td>
 </tr>
 <tr>
 <td>Extension Cable</td>
 <td>Medtronic</td>
 <td>9670560</td>
 <td></td>
 </tr>
 <tr>
 <td>Extension Cable (Number of pins 10) (x2)</td>
 <td>Bard Electrophysiology</td>
 <td>560004A</td>
 <td></td>
 </tr>
 <tr>
 <td>Extension Cable (Number of pins 4)</td>
 <td>Bard Electrophysiology</td>
 <td>560002P</td>
 <td></td>
 </tr>
 <tr>
 <td>Extension Cable </td>
 <td>St. Jude Medical</td>
 <td>ESI-42-04644-001</td>
 <td></td>
 </tr>
 <tr>
 <td>Extension Cable </td>
 <td>St. Jude Medical</td>
 <td>SJM 100011418</td>
 <td></td>
 </tr>
 <tr>
 <td>Connection Cable from IBI-Generator to MedFact RF-Ablation Catheter</td>
 <td>MedFact Engineering GmbH</td>
 <td>100-013</td>
 <td></td>
 </tr>
 <tr>
 <td>Decapolar Catheter Bard Viking 6F Josephson 115 cm</td>
 <td>Bard Electrophysiology</td>
 <td>400034</td>
 <td></td>
 </tr>
 <tr>
 <td>Multipolar (24 poles) Woven Diagnostic Electrode Catheter</td>
 <td>Bard Electrophysiology</td>
 <td>6FMC00798</td>
 <td></td>
 </tr>
 <tr>
 <td>Ensite NavX System (Version 8.1)</td>
 <td>St. Jude Medical</td>
 <td>100022310</td>
 <td></td>
 </tr>
 <tr>
 <td>Ensite System Patient Interface Unit</td>
 <td>St. Jude Medical</td>
 <td>75-05049-001</td>
 <td></td>
 </tr>
 <tr>
 <td>Ensite NavX Surface Electrode Kit</td>
 <td>St. Jude Medical</td>
 <td>EN0010-002</td>
 <td></td>
 </tr>
 <tr>
 <td>Irrigation Qiona Pump</td>
 <td>MollerMedical GmbH. Biotronik SE &amp; Co.</td>
 <td>363270</td>
 <td></td>
 </tr>
 <tr>
 <td>External Defibrillator/Monitor LifePaK12</td>
 <td>Medtronic </td>
 <td>073-20719-10</td>
 <td></td>
 </tr>
 <tr>
 <td>X-Ray C-Arm Ziehm Vision2 FD Vario</td>
 <td>Ziehm Imaging</td>
 <td>TS04_001a</td>
 <td></td>
 </tr>
 <tr>
 <td>Cardiac Ablation Generator. Software Version V3.0</td>
 <td>Irvine Biomedical, Inc. A St. Jude Medical Company</td>
 <td>IBI-1500T11</td>
 <td></td>
 </tr>
 <tr>
 <td>IBI-1500T11 Remote Control</td>
 <td>Irvine Biomedical, Inc. A St. Jude Medical Company</td>
 <td>85524</td>
 <td></td>
 </tr>
 <tr>
 <td>Dispersive Electrode Filter </td>
 <td>St. Jude Medical</td>
 <td>3183417</td>
 <td></td>
 </tr>
 <tr>
 <td>Stimulus Generator Unit for EPS 320 Cardiac Stimulator Models</td>
 <td>Micropace Pty. Ltd.</td>
 <td>MP3008</td>
 <td></td>
 </tr>
 <tr>
 <td>Lab System Pro EP Recording System</td>
 <td>Bard Electrophysiology</td>
 <td></td>
 <td>The system includes several components provided by the company</td>
 </tr>
 <tr>
 <td>NEC Multisync LCD Screen</td>
 <td>Micropace Pty. Ltd.</td>
 <td>3892D240</td>
 <td></td>
 </tr>
 <tr>
 <td>Whole Blood Microcoagulation System. Hemochron Jr.</td>
 <td>International Technidyne Corporation (ITC)</td>
 <td>HJ7023</td>
 <td></td>
 </tr>
 <tr>
 <td>Cuvettes for ACT for performance on the Hemochron</td>
 <td>International Technidyne Corporation (ITC)</td>
 <td>FB5033</td>
 <td></td>
 </tr>
 <tr>
 <td>Ultrasound Catheter ViewFlex PLUS 9 Fr.</td>
 <td>St. Jude Medical</td>
 <td>VF-PM</td>
 <td></td>
 </tr>
 <tr>
 <td>ViewFlex Catheter Interface Module</td>
 <td>St. Jude Medical</td>
 <td>20-1783-0000</td>
 <td></td>
 </tr>
 <tr>
 <td>HD11 Digital Ultrasound Machine</td>
 <td>Philips</td>
 <td>US30975460</td>
 <td></td>
 </tr>
 <tr>
 <td>CGCI, Magnetic Navigation System, Catheter Guidance, Control and Imaging System</td>
 <td>Magnetecs Corporation</td>
 <td></td>
 <td>The system includes several components provided by the company. Further support and information may be obtained at: 
 <ul>
 	<li> EU Service and Technical Support: support@magnetecs.com </li>
 <li>USA Service and Technical Support: support@magnetecs.com USA Tel. 310-649-9000</li>
 </ul>
 </td>
 </tr>
 </tbody>
</table>

remote magnetic navigation for accurate, real-time catheter positioning and ablation in cardiac electrophysiology procedures

New remote navigation systems have been developed to improve current limitations of conventional manually guided catheter ablation in complex cardiac substrates such as left atrial flutter. This protocol describes all the clinical and invasive interventional steps performed during a human electrophysiological study and ablation to assess the accuracy, safety and real-time navigation of the Catheter Guidance, Control and Imaging (CGCI) system. Patients who underwent ablation of a right or left atrium flutter substrate were included. Specifically, data from three left atrial flutter and two counterclockwise right atrial flutter procedures are shown in this report. One representative left atrial flutter procedure is shown in the movie. This system is based on eight coil-core electromagnets, which generate a dynamic magnetic field focused on the heart. Remote navigation by rapid changes (msec) in the magnetic field magnitude and a very flexible magnetized catheter allow real-time closed-loop integration and accurate, stable positioning and ablation of the arrhythmogenic substrate.

This new remote magnetic navigation system allows real-time remote catheter navigation inside the right and left atrial chambers, either in the operator or automated mode. The latter is obtained after almost instantaneous field vector adjustments of direction and intensity of torque, bending, rotating, and field gradient for axial push-pull movement (See video for illustration).
The system allows arrhythmia termination upon radiofrequency delivery in the absence of major complications (cardiac tamponade, pulmonary embolism or major hemorrhages) during this initial ablation experience (Figure 4).
The automated catheter remote navigation is highly reproducible, accurate, and rapid to position and keeps the catheter tip on the desired target. Based on five initial experimental procedures the navigation was 95.7 % reproducible, the average accuracy was 1.9&plusmn;0.9 mm and the average time to reach the target was 23.28&plusmn;14.8 sec. We considered nine targets in the right atrium (coronary sinus, 2 locations at the high right atrium, 3 locations at the tricuspid annulus, His, superior vena cava and inferior vena cava), nine targets in the left atrium (2 locations at the left atrial appendage, 3 locations at the mitral annulus and one location at each one of the pulmonary veins), six target sites in the right ventricle (2 locations at the right ventricular outflow tract, apex, right ventricle free wall, inferior wall and septum) and five more targets in the left ventricle (apex, anterior wall, lateral wall, septum and left ventricular outflow tract). Neither time, accuracy nor reproducibility to reach a target site were significantly different between chambers and targets.
<table border="1">
<tbody>
 <tr>
 <td>Type of Arrhythmia</td>
 <td>Atrial Substrate</td>
 <td>Type of ablation</td>
 <td>Acute Success</td>
 <td>Procedure-derived Complications***</td>
 <td>Recurrences</td>
 </tr>
 <tr>
 <td rowspan="3">LA flutter (n=3)</td>
 <td>Right PVs</td>
 <td>Posterior wall line</td>
 <td>Yes</td>
 <td>None</td>
 <td>No. 6 months FU</td>
 </tr>
 <tr>
 <td>Left PVs</td>
 <td>Roof line</td>
 <td>Yes*</td>
 <td>None</td>
 <td>No. 4 months FU</td>
 </tr>
 <tr>
 <td>Inferior lateral wall</td>
 <td>Focal RF delivery</td>
 <td>Yes**</td>
 <td>None</td>
 <td>No. 3 months FU</td>
 </tr>
 <tr>
 <td rowspan="2">RA flutter (N=2)</td>
 <td rowspan="2">Counterclockwise cavo-tricuspidIsthmus dependent RA flutter</td>
 <td rowspan="2">Cavo-tricuspidIsthmus line</td>
 <td>Yes</td>
 <td>None</td>
 <td>No. 10 months FU</td>
 </tr>
 <tr>
 <td>Yes</td>
 <td>None</td>
 <td>No. 11 months FU</td>
 </tr>
 </tbody>
</table>
Table 1. Atrial substrates and ablation results using the CGCI system. FU: follow up. LA: left atrium. RF: radiofrequency. RA: right atrium. PV: pulmonary vein.*Induction of 2 more non sustained and non clinical LA flutter morphologies.**LA flutter no longer re-inducible. Induction of atrial fibrillation at the end of the study.***The presence of pericardial effusion was assessed by intracardiac echocardiography throughout the procedure.
<img src="/files/ftp_upload/3658/3658fig1.jpg" alt="Figure 1" /> 
Figure 1. Agilis ES sheath (A) and MedFact magnetized and irrigated gold tip catheter (B) used for geometrical reconstruction and ablation in the right and left atrial chambers.
<img src="/files/ftp_upload/3658/3658fig2.jpg" alt="Figure 2" /> 
Figure 2. Components for remote navigation. A, motorized linear catheter advancement mechanism with a sterilizable wheel drive gearbox and a motor base. It includes a disposable sheath clip and leg mount. The magnetized catheter is inserted into the sheath and manually advanced into the right/left atrium. B, right hand 3D Controller used to steer the catheter to specific sites within the atrial chambers by changing the direction of the magnetic field. C, left hand 3-axis joystick to control the amount of catheter slack.
<img src="/files/ftp_upload/3658/3658fig3.jpg" alt="Figure 3" /> 
Figure 3. 3D electro-anatomical mapping geometry of the left atrium and pulmonary veins. A, geometrical point acquisitions within the left atrium using the magnetized catheter, which is represented with the white tip and the overlaying yellow arrow. The magnetic icon displays the coil power values as colors: green indicates a strong positive field, and red indicates a strong negative field. In blue a catheter into the coronary sinus. In red a screw-in catheter positioned in the right atrial septum. The multipolar catheter is shown in yellow. B, final view of the 3D anatomical reconstruction of the left atrium. MA; mitral annulus.
<img src="/files/ftp_upload/3658/3658fig4.jpg" alt="Figure 4"/> 
Figure 4. Interruption of a left atrial flutter circuit around the right pulmonary veins after automatically guided radiofrequency energy delivered to specific sites in the posterior wall of the left atrium. A, voltage map shows a dense scar in the posterior wall of the left atrium (grey color). B, first post-pacing interval map generated to characterize the reentrant circuit, which is localized around the right pulmonary veins (posterior view is shown). White and red indicate first post-pacing intervals &lt;30 msec. C and D, in automated mode the catheter is driven to the target points and the arrhythmia terminates after completing a line in the posterior wall of the left atrium, which interrupts the reentrant circuit. <a href="https://www.jove.com/files/ftp_upload/3658/3658fig4large.jpg" target="_blank">Click here to view larger figure</a>.

Watch this Scientific Journal Video about Remote Magnetic Navigation for Accurate, Real-time Catheter Positioning and Ablation in Cardiac Electrophysiology Procedures at JoVE.com

Remote Magnetic Navigation for Accurate, Real-time Catheter Positioning and Ablation in Cardiac Electrophysiology Procedures

This report provides a detailed description of a new remote navigation system based on magnetic driven forces, which has been recently introduced as a new robotic tool for human cardiac electrophysiology procedures.

New remote navigation systems have been developed to improve current limitations of conventional manually guided catheter ablation in complex cardiac ...

remote-magnetic-navigation-for-accurate-real-time-catheter

Research

JoVE Journal

Medicine

27.7K visualizações.  La Paz University Hospital. Este relatório fornece uma descrição detalhada de um novo sistema de navegação remota baseada em forças orientadas magnéticos, que foi recentemente introduzida como uma nova ferramenta de robótica para os procedimentos de eletrofisiologia cardíaca humanos.

Vídeo: Remote Magnetic Navigation for Accurate, Real-time Catheter Positioning and Ablation in Cardiac Electrophysiology Procedures

Neuronavigation-guided Repetitive Transcranial Magnetic Stimulation for Aphasia

Repetitive transcranial magnetic stimulation (rTMS) is widely used for several neurological conditions, as it has gained acknowledgement for its potential therapeutic effects. Brain excitability is non-invasively modulated by rTMS, and rTMS to the language areas has proved its potential effects on treatment of aphasia. In our protocol, we aim to artificially induce virtual aphasia in healthy subjects by inhibiting Brodmann area 44 and 45 using neuronavigational TMS (nTMS), and F3 of the International 10-20 EEG system for conventional TMS (cTMS). To measure the degree of aphasia, changes in reaction time to a picture naming task pre- and post-stimulation are measured and compare the delay in reaction time between nTMS and cTMS. Accuracy of the two TMS stimulation methods is compared by averaging the Talairach coordinates of the target and the actual stimulation. Consistency of stimulation is demonstrated by the error range from the target. The purpose of this study is to demonstrate use of nTMS and to describe the benefits and limitations of the nTMS compared to those of cTMS.

This study is designed to test the hypothesis that neuronavigational system-guided transcranial magnetic stimulation has higher accuracy for targeting the intended target as demonstrated by eliciting a greater degree of virtual aphasia in healthy subjects, measured by delay in reaction time to picture naming.

Repetitive transcranial magnetic stimulation (rTMS) is widely used for several neurological conditions, as it has gained acknowledgement for its potential ...

Behavior

Magnetically-Assisted Remote Controlled Microcatheter Tip Deflection under Magnetic Resonance Imaging

X-ray fluoroscopy-guided endovascular procedures have several significant limitations, including difficult catheter navigation and use of ionizing radiation, which can potentially be overcome using a magnetically steerable catheter under MR guidance.
	The main goal of this work is to develop a microcatheter whose tip can be remotely controlled using the magnetic field of the MR scanner. This protocol aims to describe the procedures for applying current to the microcoil-tipped microcatheter to produce consistent and controllable deflections.
	A microcoil was fabricated using laser lathe lithography onto a polyimide-tipped endovascular catheter. In vitro testing was performed in a waterbath and vessel phantom under the guidance of a 1.5-T MR system using steady-state free precession (SSFP) sequencing. Various amounts of current were applied to the coils of the microcatheter to produce measureable tip deflections and navigate in vascular phantoms.
	The development of this device provides a platform for future testing and opportunity to revolutionize the endovascular interventional MRI environment.

Current applied to an endovascular microcatheter with microcoil tip made by laser lathe lithography can achieve controllable deflections under magnetic resonance (MR) guidance, which may improve speed and efficacy of navigation of vasculature during various endovascular procedures.

X-ray fluoroscopy-guided  endovascular procedures have several significant limitations, including  difficult catheter navigation and use of ionizing ...

Bioengineering

Robotic Ablation of Atrial Fibrillation

Background: Pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). During PVI an electrical conduction block between pulmonary vein (PV) and left atrium (LA) is created. This conduction block prevents AF, which is triggered by irregular electric activity originating from the PV. However, transmural atrial lesions are required which can be challenging. Re-conduction and AF recurrence occur in 20 - 40% of the cases. Robotic catheter systems aim to improve catheter steerability. Here, a procedure with a new remote catheter system (RCS), is presented. Objective of this article is to show feasibility of robotic AF ablation with a novel system. Materials and Methods: After interatrial trans-septal puncture is performed using a long sheath and needle under fluoroscopic guidance. The needle is removed and a guide wire is placed in the left superior PV. Then an ablation catheter is positioned in the LA, using the sheath and wire as guide to the LA. LA angiography is performed over the sheath. A circular mapping catheter is positioned via the long sheath into the LA and a three-dimensional (3-D) anatomical reconstruction of the LA is performed. The handle of the ablation catheter is positioned in the robotic arm of the Amigo system and the ablation procedure begins. During the ablation procedure, the operator manipulates the ablation catheter via the robotic arm with the use of a remote control. The ablation is performed by creating point-by-point lesions around the left and right PV ostia. Contact force is measured at the catheter tip to provide feedback of catheter-tissue contact. Conduction block is confirmed by recording the PV potentials on the circular mapping catheter and by pacing maneuvers. The operator stays out of the radiationfield during ablation. Conclusion: The novel catheter system allows ablation with high stability on low operator fluoroscopy exposure.

Pulmonary vein isolation (PVI) with an ablation catheter is a curative treatment for atrial fibrillation (AF). Robotic catheter systems aim to improve catheter steerability. Here, a procedure with a new robotic catheter system is presented. The goal of the procedure is electrical block between pulmonary vein and left atrium.

Background: Pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). During PVI an electrical conduction block between ...

Non-fluoroscopic Catheter Tracking for Fluoroscopy Reduction in Interventional Electrophysiology

A technological platform (MediGuide) has been recently introduced for non-fluoroscopic catheter tracking. In several studies, we have demonstrated that the application of this non-fluoroscopic catheter visualization system (NFCV) reduces fluoroscopy time and dose by 90-95% in a variety of electrophysiology (EP) procedures. This can be of relevance not only to the patients, but also to the nurses and physicians working in the EP lab. Furthermore, in a subset of indications such as supraventricular tachycardias, NFCV enables a fully non-fluoroscopic procedure and allows the lab staff to work without wearing lead aprons. With this protocol, we demonstrate that even complex procedures such as ablations of atrial fibrillation, that are typically associated with fluoroscopy times of &#62;30 min in conventional settings, can safely be performed with a reduction of &#62;90% in fluoroscopy exposure by the additional use of NFCV.

Radiation exposure is an underestimated risk in complex ablation procedures. Here, we describe a protocol to significantly decrease fluoroscopy time and dosage for both the patient and the lab staff by using a novel non-fluoroscopic catheter visualization system.

A technological platform (MediGuide) has been recently introduced for non-fluoroscopic catheter tracking. In several studies, we have demonstrated that ...

Ablation of Ischemic Ventricular Tachycardia Using a Multipolar Catheter and 3-dimensional Mapping System for High-density Electro-anatomical Reconstruction

Ventricular tachycardia (VT) in patients with ischemic cardiomyopathy mainly results from endocardial scars after myocardial infarction; those scars represent zones of slow conduction that allow the occurrence and maintenance of reentrant circuits. Catheter ablation enables substrate modification of those low voltage areas and thus can help to alter the scar tissue in such a way that arrhythmias cannot appear anymore. Hospitalizations of concerned patients decrease, quality of life and outcome rise. Consequently, VT ablation represents a growing field in electrophysiology, especially for patients with endocardial scars in ischemic heart disease after myocardial infarction. However, ablation of ventricular tachycardia remains one of the most challenging procedures in the electrophysiology lab. Precise scar definition and localization of abnormal potentials are critical for ablation success. The following manuscript describes the use of a multipolar mapping catheter and 3-dimensional (3D) mapping system to create a high density electro-anatomical map of the left ventricle including a precise scar representation as well as mapping of fractionated and late potentials in order to allow a highly accurate substrate modification.

With the following protocol, we provide an approach to Ventricular Tachycardia (VT) ablation using high density mapping with a multipolar catheter and 3D mapping system enhancing the success of the procedure.

Ventricular tachycardia (VT) in patients with ischemic cardiomyopathy mainly results from endocardial scars after myocardial infarction; those scars ...

Electromagnetic Navigation Transthoracic Nodule Localization for Minimally Invasive Thoracic Surgery

The increased use of chest computed tomography (CT) has led to an increased detection of pulmonary nodules requiring diagnostic evaluation and/or excision. Many of these nodules are identified and excised via minimally invasive thoracic surgery; however, subcentimeter and subsolid nodules are frequently difficult to identify intra-operatively. This can be mitigated by the use of electromagnetic transthoracic needle localization. This protocol delineates the step-by-step process of electromagnetic localization from the pre-operative period to the postoperative period and is an adaptation of the electromagnetically guided percutaneous biopsy previously described by Arias et al. Pre-operative steps include obtaining a same day CT followed by the generation of a three-dimensional virtual map of the lung. From this map, the target lesion(s) and an entry site are chosen. In the operating room, the virtual reconstruction of the lung is then calibrated with the patient and the electromagnetic navigation platform. The patient is then sedated, intubated, and placed in the lateral decubitus position. Using a sterile technique and visualization from multiple views, the needle is inserted into the chest wall at the prechosen skin entry site and driven down to the target lesion. Dye is then injected into the lesion and, then, continuously during needle withdrawal, creating a tract for visualization intra-operatively. This method has many potential benefits when compared to the CT-guided localization, including a decreased radiation exposure and decreased time between the dye injection and the surgery. Dye diffusion from the pathway occurs over time, thereby limiting intra-operative nodule identification. By decreasing the time to surgery, there is a decrease in wait time for the patient, and less time for dye diffusion to occur, resulting in an improvement in nodule localization. When compared to electromagnetic bronchoscopy, airway architecture is no longer a limitation as the target nodule is accessed via a transparenchymal approach. Details of this procedure are described in a step-by-step fashion.

Presented here is a protocol for lung nodule localization using dye marking via electromagnetically navigated transthoracic needle access. The technique described here can be accomplished in the peri-operative period to optimize nodule localization and to successful resection when performing minimally invasive thoracic surgery.

The increased use of chest computed tomography (CT) has led to an increased detection of pulmonary nodules requiring diagnostic evaluation and/or ...

Real-Time Magnetic Resonance Guided Focused Ultrasound for Painful Bone Metastases

Bones are one of the most common sites of cancer metastasis, which usually causes pain and impairs quality of life. Radiation therapy combined with opioids is the standard treatment for painful bone metastases. This treatment achieves effective pain control in 60&#8722;74% of patients, but limited treatment choices with limited benefits are available for recurrent or residual painful bone metastases after radiotherapy. More than 40% of patients still experience moderate to severe bone pain after reirradiation. Magnetic resonance-guided focused ultrasound (MRgFUS) combines high-intensity focused ultrasound, which achieves thermal ablation of bone metastases and subsequent pain reduction, with real-time magnetic resonance (MR) thermometry to monitor the temperature of anatomic MR images, with an accuracy of 1 &#176;C, spatial resolution of 1 mm, and temporal resolution within 3 s. As well as being increasingly used clinically for controlling metastatic bone pain, the use of MRgFUS for other diseases has also been tested. However, the use of MR software as a thermometer is the only technique available to verify the accuracy of the software and assure energy delivery. Here, we describe an efficient method of quality assurance we developed for thermal detection and energy delivery before each MRgFUS treatment and also propose a modified workflow to expedite the treatment course as well as to reduce patients&#39; pain during the procedure.

Magnetic resonance could offer real-time monitoring of the position and temperature of focused ultrasound in thermal ablation for painful bone metastases, regardless of cancer type or previous local treatments. Our innovative method of quality assurance could facilitate the application of this effective and safe treatment.

Bones are one of the most common sites of cancer metastasis, which usually causes pain and impairs quality of life. Radiation therapy combined with ...

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing

It is now well recognized that heart failure (HF) patients with left bundle branch block (LBBB) derive substantial clinical benefits from cardiac resynchronization therapy (CRT), and LBBB has become one of the important predictors for CRT response. The conventional tachypacing-induced HF model has several major limitations, including absence of stable LBBB and rapid reversal of left ventricular (LV) dysfunction after cessation of pacing. Hence, it is essential to establish an optimal model of chronic HF with isolated LBBB for studying CRT benefits. In the present study, a canine model of asynchronous HF induced by left bundle branch (LBB) ablation and 4 weeks of rapid right ventricular (RV) pacing is established. The RV and right atrial (RA) pacing electrodes via the jugular vein approach, together with an epicardial LV pacing electrode, were implanted for CRT performance. Presented here are the detailed protocols of radiofrequency (RF) catheter ablation, pacing leads implantation, and rapid pacing strategy. Intracardiac and surface electrograms during operation were also provided for a better understanding of LBB ablation. Two-dimensional speckle tracking imaging and aortic velocity time integral (aVTI) were acquired to validate the chronic stable HF model with LV asynchrony and CRT benefits. By coordinating ventricular activation and contraction, CRT uniformed the LV mechanical work and restored LV pump function, which was followed by reversal of LV dilation. Moreover, the histopathological study revealed a significant restoration of cardiomyocyte diameter and collagen volume fraction (CVF) after CRT performance, indicating a histologic and cellular reverse remodeling elicited by CRT. In this report, we described a feasible and valid method to develop a chronic asynchronous HF model, which was suitable for studying structural and biologic reverse remodeling following CRT.

The establishment of a chronic asynchronous heart failure (HF) model by rapid pacing combined with left bundle branch ablation is presented. Two-dimensional speckle tracking imaging and aortic velocity time integral are applied to validate this stable HF model with left ventricular asynchrony and the benefits of cardiac resynchronization therapy.