Introduction and objective: This problem can be addressed successfully using several different approaches described in this report. Epub 2018 Apr 6. Bidirectional block established at the end of the procedure. The following approaches can be employed to address this problem: CTI ablation with uptitration of power guided by impedance and temperature monitoring, as performed in our case, can counteract the “heat sink” effect. Of the 29 patients, 26 (90%) had an inducible arrhythmia before CTI ablation--AF in 16, typical atrial flutter (AFL) in seven and atypical AFL in three. 2). Ablation of atrial fibrillation: what is the gold standard strategy? CTI ablation was performed in patients who had long-standing AF or atrial flutter episodes during the admission period. PV isolation was achieved by endocardial touch-up in 11 patients in this study. CTI was ablated in patients with long-standing AF (continuous AF lasting for ≥1 year) or those who had AFL episodes during the admission period. J Interv Card Electrophysiol. Epub 2013 Mar 14. The venous drainage of the human myocardium. Ablation index (AI) has been evaluated as guidance quality marker for pulmonary vein isolation, but not for linear ablation of the cavotricuspid isthmus (CTI) for typical right atrial flutter (AFL). Epub 2003 Nov 10. Angiographically determined CTI morphology was classified as either simple or complex due to pouchlike recesses. PV potentials were checked in 33 (52.4%) patients among the 63 patients in the CTI ablation group, and 11 patients showing residual PV potentials underwent additional PV antral ablation. Several additional factors can contribute to inadequate CTI ablation. | A pouchlike recess of the CTI was present in 9.6% of autopsy hearts. The mean age of all patients was 55.8 ± 8.8 years, and the median CHA2DS2VASc score was 1 (1–2) point. Prophylactic CTI ablation at the time of a first PVI does not seem to improve long-term freedom from AF. Prophylactic pulmonary vein isolation during isthmus ablation for atrial flutter: Three-year outcomes of the PREVENT AF I study. As an additional procedure with TTA, however, time and cost may be a concern when employing a staged approach associated with catheter ablation. Presented at the Annual Meeting of the European Heart Rhythm Association Congress, Barcelona, Spain, 19 March 2018. Electrocardiogram showed the same pattern of typical atrial flutter (, A repeat electrophysiologic study was performed. Shah DC, Sunthorn H, Burri H, Gentil-Baron P. J Cardiovasc Electrophysiol. Please enable it to take advantage of the complete set of features! AI guidance vs CF guidance was associated with: higher first‐pass conduction block of CTI (93.0% vs 76.2%, P = .03) with similar ablation time; similar acute spontaneous CTI reconnection 2.3% vs 9.5%, P = .343); fewer radiofrequency (RF) applications (10.1 ± 2.8 vs 11.5 ± 3.0, P = .031) needed to achieve CTI directional block; significantly higher mean ablation time, impedance drop, force time integral and AI and similar mean CF and power of each VisiTag point. NCI CPTC Antibody Characterization Program. Learn about our remote access options, Department of Cardiology, Beijing Anzhen Hospital Affiliated to Capital Medical University, Beijing, China. Prominent crista terminalis and Eustachian ridge in the right atrium: Two dimensional (2D) and three dimensional (3D) imaging. The interindividual anatomic variability can influence the duration and outcome of ablation procedure. PVI is a well-established therapy for patients with drug refractory atrial fibrillation (AF). Kron J, Kasirajan V, Wood MA, Kowalski M, Han FT, Ellenbogen KA. When the rhythm was stable and both atrial activities were restored, antiarrhythmic drugs were discontinued at 3–6 months after TTA. The procedure, although promising, has still scarce data. This might affect the results of this study, but the same limitation is inherent in previous studies using various rhythm monitoring methods and different definitions of success. The primary outcome was survival rate free from ATa recurrence. A more lateral ablation line can be performed that increases the distance from the medial portion of the SCV where the vessel has a large caliber. The additional price of CTI ablation may be offset by the lower recurrence rate, making additional CTI ablation cost-effective compared with TTA alone as shown in a recent study on the cost-effectiveness of a hybrid ablation procedure [18]. Standard definition of CTI morphologic variants is recommended. To the best of our knowledge, this is the first study to investigate the clinical benefit of additional CTI ablation after TTA as a rapid 2-stage hybrid procedure. AFL is often preceded by AF, and sometimes AF is converted to AFL by Class 1c antiarrhythmic drugs. Continuous variables are presented as median (25th–75th percentiles) or mean ± standard deviation based on the assumption of normality, whereas categorical variables are presented as number and percentage. Survival free of AF (Log rank p = .965) and annual relapse rates were similar in the two groups - 10.9%/year vs 10.1%/year (PVI vs PVI + CTI, respectively, p = .97). Based on early experiences of patients showing CTI-dependent AFL after TTA, we began to perform CTI ablation in selected patients. If you do not receive an email within 10 minutes, your email address may not be registered, Among 53 patients with recurrent ATa, 41 had AF (77.4%) whereas the rest had atrial tachycardia or flutter (n = 12, 22.6%). J Cardiovasc Electrophysiol. However, future randomized studies are needed before CTI ablation can be routinely recommended in patients undergoing TTA. Rev Port Cardiol. Correspondence Xuejun Ren, MD, Department of Cardiology, Beijing Anzhen Hospital Affiliated to Capital Medical University, 2 Anzhen Road, Chaoyang District, 100029 Beijing, China. Intracardiac echocardiography from the redo cavotricuspid isthmus ablation procedure. Please check for further notifications by email. Success rates were 83% in patients without and 73% in patients with inducible arrhythmias at the end of the procedure (p=NS). The CTI ablation group showed a significantly higher survival rate free from recurrent ATa than that of the non-CTI ablation group at 5 years (52.5% vs 41.4%, P = 0.046). 2009 Oct;28(10):1043-6. Get the latest research from NIH: https://www.nih.gov/coronavirus. The inferior right atrial isthmus: further architectural insights for current and coming ablation technologies. We conducted this study to verify the effect of CTI ablation on ATa recurrence after TTA of AF. This study had several limitations. The interindividual anatomic variability can influence the duration and outcome of ablation procedure. The Shapiro–Wilks test was used to test the assumption of normality. An intracardiac echocardiography catheter (ICE; ACUNAV, Siemens, Mountain View, CA) was inserted through the right femoral vein (, Below, we discuss common anatomic variants that can interfere with CTI ablation and their applicability in our case (, Ablation line more laterally than usual position, Use of an irrigated ablation catheter and/or contact force–sensing catheters, Circular ablation to isolate the pouch and anchoring to the IVC and tricuspid annulus, Ablation line more medially than usual position, Arching the ablation catheter to prevent contact with the Eustachian ridge, Ablation line more laterally away from the SCV, Temporary obstruction of SCV ostium with a catheter or angioplasty balloon. Minimally invasive surgical techniques have been developed as an alternative to the best-known surgical ablation method, the maze operation. J Interv Card Electrophysiol. A meta-analysis. However, certain aspects of the regional anatomy can pose technical challenges such that bidirectional block across the CTI can be difficult to achieve. It should be noted that a lateral ablation line will not be effective if the “heat sink” phenomenon is due to a prominent RCA, as the caliber of the vessel is in fact larger more laterally on the tricuspid annulus. Epub 2015 May 26. Outcomes of cryoballoon or radiofrequency ablation in symptomatic paroxysmal or persistent atrial fibrillation. In addition, patients in the CTI ablation group were followed up for a longer period than those in the non-CTI ablation group. A cavotricuspid isthmus (CTI) block may be an easier and safer alternative to left atrial lines for this purpose. It also has a potential role in substrate modification in AF [10, 11]. Intravascular blood flow in proximity to the tissue where RF energy is applied may result in convective heat loss and ineffective lesion formation. A prior study of ablation of epicardial accessory pathways in the posteroseptal region reported that coronary injury happened in 50% of cases when RF was performed within 2 mm from the artery. Our results may not represent all the AF patients undergoing TTA because of differences in study populations, ablation techniques and surgical skills. Color flow Doppler ultrasound can be useful to distinguish SCV flow from arterial flow from the RCA and define the spatial relationship of the vessels to the CTI. This site needs JavaScript to work properly. The technique required a bilateral approach with 3 holes: a 5-mm port introduced in the 4th intercostal space at the midaxillary line and 2 ports placed in the 3rd intercostal space at the anterior axillary line and at the 6th intercostal space at the midaxillary line, respectively. In our experience, patients undergoing additional CTI ablation did not develop procedure-related complications or show an extended duration of hospital stay. After pericardial tenting, a lighted dissector (AtriCure Lumitip Dissector, Atricure, Inc., Cincinnati, OH, USA) was used to pass a rubber band under the pulmonary vein (PV) antrum through the oblique sinus. Straka Z, Budera P, Osmančík P, Malý M, Vaněk T. De Maat GE, Pozzoli A, Scholten MF, Van Gelder IC, Blaauw Y, Mulder BA et al. Epub 2017 Jan 9. The Eustachian ridge divides the CTI into an anterior sub-Eustachian portion between the Eustachian ridge and the tricuspid annulus, and a more posterior portion leading from the ridge to the anterior border of the IVC. 2003 Nov 18;108(20):2479-83. doi: 10.1161/01.CIR.0000101684.88679.AB. Get the latest public health information from CDC: https://www.coronavirus.gov. De Sisti A, Leclercq JF, Fiorello P, Palamara A, Attuel P. Romero J, Diaz JC, Di Biase L, Kumar S, Briceno D, Tedrow UB, Valencia CR, Baldinger SH, Koplan B, Epstein LM, John R, Michaud GF, Stevenson WG. All the tests were 2-sided, and a P-value <0.05 was considered statistically significant. https://doi.org/10.1016/j.hrthm.2019.05.030. A prior study demonstrated that the SCV was absent in 31% of cases, smaller (<1 mm) in diameter in 40%, and larger caliber (≥1 mm) in 29%. NIH By continuing you agree to the Use of Cookies. Altman RK, Proietti R, Barrett CD, Paoletti Perini A, Santangeli P, Danik SB et al. Furthermore, TTA has a pitfall that CTI ablation cannot be performed by a single procedure. A meta-analysis. Entrainment maneuvers were consistent with CTI-dependent, counterclockwise atrial flutter. ATa: atrial tachyarrhythmia; CTI: cavotricuspid isthmus. All patients were treated with anticoagulants during the first 3 months, and the treatment was continued at the discretion of cardiologists. In the field of surgical ablation, a minimally invasive procedure is one of the fastest growing methods to replace traditional surgical ablations because favourable long-term outcomes have been reported [12, 13]. Hye Bin Gwag, Dong Seop Jeong, Jin Kyung Hwang, Seung-Jung Park, Kyoung-Min Park, June Soo Kim, Young Keun On, Additional cavotricuspid isthmus ablation may reduce recurrent atrial tachyarrhythmia after total thoracoscopic ablation for persistent atrial fibrillation, Interactive CardioVascular and Thoracic Surgery, Volume 28, Issue 2, February 2019, Pages 177–182, https://doi.org/10.1093/icvts/ivy236. In the present study, we investigated whether CTI ablation would reduce recurrent ATa in patients who underwent TTA for persistent AF. A 3.5-millimeter open irrigated tip radiofrequency (RF) ablation catheter (THERMOCOOL, Biosense Webster, Irvine, CA) was used. Portuguese]. If residual PV potentials were detected, endocardial PV antral ablation was performed. After PV and ganglionated plexus ablation, the ligament of Marshall was dissected and ablated. The sub-Eustachian pouch (pouch of Keith) is a physiologic depression of the CTI just anterior to the Eustachian ridge and laterally to the Thebesian valve at the orifice of the coronary sinus. First-in-children epicardial mapping of the heart: unravelling arrhythmogenesis in congenital heart disease, Development of a porcine model of emergency resternotomy at a low-volume cardiac surgery centre, Donor risk analysis and validation in heart transplants: a single-centre experience, Assessing palliative care need in left ventricular assist device patients and heart transplant recipients, A recurrent lung abscess caused by delayed diagnosis of unique co-infection with, About Interactive CardioVascular and Thoracic Surgery, About the European Association for Cardio-Thoracic Surgery, About the European Board of Cardiovascular Perfusion, https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model, Receive exclusive offers and updates from Oxford Academic. After multivariable adjustment, however, only CTI ablation and smaller left atrial volume index were significant predictors of freedom from ATa recurrence. Radiofrequency (RF) catheter ablation of the cavotricuspid isthmus (CTI) in typical or common atrial flutter (AFL) is recommended for patients who are symptomatic or refractory to pharmacologic rate control. Get the latest research from NIH: https://www.nih.gov/coronavirus. 2017 Apr;48(3):307-315. doi: 10.1007/s10840-016-0211-9. Clipboard, Search History, and several other advanced features are temporarily unavailable. Types of ATa were classified as AF or ATa other than AF (atrial tachycardia or flutter) based on all available data, including 12-lead electrocardiograms and electrophysiological study results. We thus studied the feasibility and effectiveness of AI-guided CTI for AFL. HHS In patients with prominent pectinate muscles ablation can be preferably performed more medially to avoid the pectinates. Introduction. The aim of this study is to assess whether CTI ablation after PV isolation reduces inducibility of … The cavotricuspid isthmus (CTI) in the lower pan of the right atrium, between the inferior caval vein and the tricuspid valve, is considered crucial in producing a conduction delay and. AI‐guided ablation of CTI line for AFL appears feasible and effective with similar ablation time, fewer RF applications, a higher rate of first‐pass conduction block, and no additional complications. Introduction: PVI is a well-established therapy for patients with drug refractory atrial fibrillation (AF). 2018 Jun;29(6):872-878. doi: 10.1111/jce.13485. Our results showed that patients with additional CTI ablation had better outcomes than that of patients without CTI ablation in ATa recurrence. The purpose of this study was to establish complication rates in patients undergoing RF catheter ablation for CTI-dependent AFL, assess the role of CTI morphology in procedural success, and determine the anatomic variability of CTI ex vivo. Wazni O, Marrouche NF, Martin DO, Gillinov AM, Saliba W, Saad E, Klein A, Bhargava M, Bash D, Schweikert R, Erciyes D, Abdul-Karim A, Brachman J, Gunther J, Pisano E, Potenza D, Fanelli R, Natale A. Direct energy deposition occurs within only 0.5–0.8 mm of the catheter electrode surface. Unlike catheter ablation, little is known about the benefits of cavotricuspid isthmus (CTI) ablation in total thoracoscopic ablation (TTA) of atrial fibrillation (AF). Numerical analysis of thermal impact of intramyocardial capillary blood flow during radiofrequency cardiac ablation. In patients with cavotricuspid isthmus (CTI)-dependent atrial flutter, ablation along the CTI is often a routine and straightforward procedure. USA.gov. The AF-free survival rate at 1 year was higher in the CTI ablation group than the non-CTI ablation group (93.7% vs 79.6%, P = 0.02), while the 3-year and 5-year survival rates were not different between the groups (83.0% vs 66.9%, P = 0.10 at 3 years; 61.0% vs 44.6%, P = 0.38 at 5 years). 2017 Apr;48(3):307-315. doi: 10.1007/s10840-016-0211-9. Verma A, Macle L, Cox J, Skanes AC; CCS Atrial Fibrillation Guidelines Committee. PV isolation was confirmed using a Lasso catheter (Biosense Webster, Inc., Diamond Bar, CA, USA) in patients for whom a surgeon acknowledged that PV antrum ablation was insufficient because of anatomical accessibility. Radiofrequency (RF) catheter ablation is one of the most common strategies for the current management of cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL). This study aimed to investigate the incidence of recurrent atrial tachyarrhythmia (ATa) according to additional CTI ablation after TTA in patients with persistent AF. A fluoroscopic image merged with a 3-dimensional image of the reconstructed right atrium shows the catheter positions and point-by-point ablation lesions in cavotricuspid isthmus (B). BACKGROUND: Ablation index (AI) has been evaluated as guidance quality marker for pulmonary vein isolation, but not for linear ablation of the cavotricuspid isthmus (CTI) for typical right atrial flutter (AFL). Three (10%) were non-inducible. Conclusion. However, it remains unclear whether prophylactic cavotricuspid isthmus (CTI) ablation at the time of PVI improves long-term freedom from AF. Epub 2014 Apr 9. Tel: +82-2-34103419; fax: +82-2-34103849; e-mail: Relationship between atrial fibrillation and typical atrial flutter in humans: activation sequence changes during spontaneous conversion, Inter-relationships between atrial flutter and atrial fibrillation, Risk of atrial fibrillation after atrial flutter ablation: impact of AF history, gender, and antiarrhythmic drug medication, Incidence of new-onset atrial fibrillation after cavotricuspid isthmus ablation for atrial flutter, Ablation of atrial fibrillation at the time of cavotricuspid isthmus ablation in patients with atrial flutter without documented atrial fibrillation derives a better long-term benefit, 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on practice guidelines and the Heart Rhythm Society, 2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS, Surgical vs. transcatheter pulmonary vein isolation as first invasive treatment in patients with atrial fibrillation: a matched group comparison, Pulmonary vein isolation to reduce future risk of atrial fibrillation in patients undergoing typical flutter ablation: results from a randomized pilot study (REDUCE AF), Atrial fibrillation ablation: importance of cavotricuspid isthmus block, Surgical ablation as treatment for the elimination of atrial fibrillation: a meta-analysis, Treatment of stand-alone atrial fibrillation with a right thoracoscopic approach employing a microwave or monopolar radiofrequency energy source: long-term results, Long-term results of surgical minimally invasive pulmonary vein isolation for paroxysmal lone atrial fibrillation, Mechanisms of atrial tachyarrhythmias following surgical atrial fibrillation ablation, Management of recurrent atrial arrhythmias after minimally invasive surgical pulmonary vein isolation and ganglionic plexi ablation for atrial fibrillation, Management of refractory atrial fibrillation post surgical ablation, Meta-analysis of ablation of atrial flutter and supraventricular tachycardia, Cost-effectiveness of the convergent procedure and catheter ablation for non-paroxysmal atrial fibrillation, Hybrid ablation for atrial fibrillation: a systematic review, Prolonged rhythm monitoring for the detection of occult paroxysmal atrial fibrillation in ischemic stroke of unknown cause. Supported by the Registry for Cardio-cerebro-vascular Pathology, Veneto Region, Venice, Italy. After multivariable adjustment, CTI ablation (hazard ratio 0.46, 95% confidence interval 0.217–0.971; P = 0.04) and the left atrial volume index (hazard ratio 1.05, 95% confidence interval 1.029–1.070; P < 0.001) were significantly correlated with ATa recurrence (Table 2). ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. Anatomy of the cavotricuspid isthmus for radiofrequency ablation in typical atrial flutter, Registry for Cardio-cerebro-vascular Pathology. Conclusion: © The Author(s) 2018. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (. To compare the outcomes of patients who underwent PVI alone vs. PVI + prophylactic CTI ablation. After excluding those with documented/inducible atrial flutter (n = 233), 1698 individuals were available for matching. Navarrete A, Conte F, Moran M, Ali I, Milikan N. January CT, Wann LS, Alpert JS, Calkins H, Cigarroa JE, Cleveland JCJr et al. The following parameters should be considered: Inadequate power titration is a common reason of incomplete CTI block. A randomized trial of contact force in atrial flutter ablation. 2013 Jul;24(7):742-51. doi: 10.1111/jce.12121. The relationship between AFL and AF has been established for many years. Histomorphometric analysis of the CTI atrial wall demonstrated that the central level was the thinnest in the 3 sectors and the paraseptal level was the thickest. Acute procedure failure or major complications occurred in 3 cases, all with complex CTI anatomy. Patients with CTI ablation showed a better survival rate free from recurrent ATa compared with the non-CTI ablation group. Kirchhof P, Benussi S, Kotecha D, Ahlsson A, Atar D, Casadei B et al. AF: atrial fibrillation; CTI: cavotricuspid isthmus; RFA: radiofrequency ablation; TTA: total thoracoscopic ablation. This study aimed to investigate the incidence of recurrent atrial tachyarrhythmia (ATa) according to additional CTI ablation after TTA in … In the case of CTI ablation, the distal right coronary artery (RCA) and small cardiac vein (SCV) run on the epicardial aspect of the CTI and may cause a “heat sink” effect. J Cardiovasc Electrophysiol. Published by Elsevier B.V. NLM Note that a prominent SCV is present in. Accordingly, the current guidelines for the management of AF indicate that cavotricuspid isthmus (CTI) ablation may be beneficial for some patients. Empirical cavotricuspid isthmus line for atrial fibrillation ablation is futile "Repetita Iuvant". CTI: cavotricuspid isthmus; LAVI: left atrium volume index; LVEF: left ventricular ejection fraction. Results: Before discharge after TTA, confirmation of PV isolation or catheter-based endocardial ablation was performed for selected patients. DOI: https://doi.org/10.1016/j.hrcr.2019.09.004. Patients were considered to have indeterminate recurrence in the presence of missing 24-h Holter monitoring measurements and no symptoms or 12-lead electrocardiograms suggestive of recurrence. Because the detection of intermittent AF depends on the type and the timing of cardiac monitoring, longer-term monitoring, such as 7-day Holter or an implantable loop recorder, could enhance the detection of recurrent ATa [20]. First, this was a retrospective single-centre study. Copyright © 2020 Elsevier Inc. except certain content provided by third parties. NIH There was no difference in the baseline characteristics between the CTI ablation and non-CTI ablation groups, except for a higher proportion of male patients in the CTI ablation group (98.4% vs 89.0%, P = 0.03) (Table 1). We use cookies to help provide and enhance our service and tailor content and ads. Diagnostic catheters were positioned in the high right atrium, annular right atrium across the CTI, coronary sinus, and right ventricle. In patients with a prominent sub-Eustachian pouch, the catheter can be positioned more laterally to allow better tissue contact and avoid rapid temperature and impedance rises. 1). Division of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. However, it remains unclear whether prophylactic cavotricuspid isthmus (CTI) ablation at the time of PVI improves long-term freedom from AF. Find NCBI SARS-CoV-2 literature, sequence, and clinical content: https://www.ncbi.nlm.nih.gov/sars-cov-2/. Bipolar radiofrequency energy was delivered 6 times to the clamps around the PV for isolation. National Center for Biotechnology Information, Unable to load your collection due to an error, Unable to load your delegates due to an error, [Article in We believe that this study drives the need for further investigations into cost-effectiveness and patient selection for this strategy. [The effects of the ablation of atrial flutter in patients with and without a clinical history of paroxysmal atrial fibrillation]. In the univariable analysis, 3 variables including both CTI ablation and PV touch-up were significantly associated with ATa recurrence. However, certain aspects of the regional anatomy can pose technical challenges such that bidirectional block across the CTI can be difficult to achieve. Please check your email for instructions on resetting your password. Total thoracoscopy was defined as a video-assisted thoracoscopic surgical technique without the aid of a Da Vinci system and cardiopulmonary bypass. This approach was also used in our case. Previous studies not only showed that new-onset AF develops in a significant proportion of patients with AFL but also advocated ablation of AF at the time of CTI ablation in patients with AFL [4, 5, 9]. A cavotricuspid isthmus (CTI) block may be an easier and safer alternative to left atrial lines for this purpose. Search for other works by this author on: Department of Thoracic and Cardiovascular Surgery, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. Recommended ablation settings include an initial power of 5 W and slowly uptitrating to 20 W with a maximum temperature setting of 40°C and a flow rate of 17 mL/min. Atrial flutter (AFL) commonly co-exists with atrial fibrillation (AF) in clinical practice, and the inter-relationship between AFL and AF has long been recognized [1, 2]. Macroscopic and histologic examination of the CTI was performed in 104 heart specimens from consecutive autopsies. Characterization of atrial flutter after pulmonary vein isolation by cryoballoon ablation. There are no established guidelines for indication, approach or lesion sets of the procedure. 2). The ventricular beginning point of the ablation was determined by atrial to ventricular electrogram amplitude ratio <1/3, and the ablation catheter was dragged towards the atrial side with a 60-s delay at each ablation point. A definite recommendation for a safe distance between the SCV and the RCA cannot be made. HHS The full text of this article hosted at iucr.org is unavailable due to technical difficulties. Cardiogenic shock resolved and there was no recurrence of arrhythmia (Figure 1E). USA.gov. Get the latest public health information from CDC: https://www.coronavirus.gov. Image, Download Hi-res Although RF catheter ablation is a safe and effective procedure for AFL treatment, CTI anatomic complexity can affect ablation parameters and outcome. En, CI: confidence interval; CTI: cavotricuspid isthmus; LAVI: left atrium volume index; PV: pulmonary vein. By continuing you agree to the use of cookies. In patients with cavotricuspid isthmus (CTI)-dependent atrial flutter, ablation along the CTI is often a routine and straightforward procedure. Placement of a catheter in the ostium of the SCV to temporarily obstruct venous blood flow and reduce the “heat sink” effect can be considered. The recognition of these variations, primarily with the use of intraprocedural ICE, is critical in developing effective and safe troubleshooting approaches.