Early Clinical Outcomes and Advantages of a Novel-Size Adjustable Second-Generation Cryoballoon: A Proof-of-Concept Study.

(1) Background/Objective Balloon-guided catheter ablation (CA) has emerged as an alternative option for atrial fibrillation (AF) management. The recent introduction of a novel-size adjustable second-generation cryoballoon (CB) system offers innovations, but clinical outcomes remain unexplored. This study aims to assess the acute performance of the POLARx FIT™ CB system in AFCA. (2) Methods: Consecutive patients undergoing AF ablation with the POLARx FIT™ CB system in our center were included. The primary outcome was the rate of 31 mm balloon-size utilization, with secondary outcomes including acute pulmonary vein isolation (PVI) rate, periprocedural complications, and in-hospital AF recurrences. (3) Results: Twenty-four patients with a mean age of 59.5 years, predominantly male (87.5%), and exhibiting paroxysmal AF (91.7%) were enrolled. Procedural characteristics demonstrated a high acute success rate (100% PV isolation) with a favorable safety profile. Notably, the 31 mm CB configuration was utilized in 51% of applications, showcasing its adaptability in challenging anatomies. No major complications occurred, with two patients experiencing in-hospital self-limiting AF recurrences. (4) Conclusions: This study represents the first comprehensive assessment of the POLARx FIT™ CB system in AF ablation. While acknowledging the study's limitations, this novel CB emerges as a promising tool, warranting further exploration in larger studies with extended follow-up periods.

TriGuard Embolic Protection Device in percutaneous cardiac interventions with intracavitary cardiac thrombosis: A case series.

Embolic cerebral protection devices are not routinely used in clinical practice during electrophysiological interventions. We report a case series of patients with intracardiac thrombosis undergoing a percutaneous left atrial appendage (LAA) closure and a ventricular tachycardia (VT) catheter ablation supported by TriGuard 3 Cerebral Embolic Protection Device.

Pulsed-field ablation of pulmonary vein and left atrial posterior wall combined with left atrial appendage occlusion as single procedure.

Pulmonary vein isolation and left atrial posterior wall ablation using the Farapulse system, followed by left atrial appendage occlusion, have been achieved as single combined procedure to treat long-standing persistent atrial fibrillation in a patient at high hemorrhagic risk.

What's behind your eosinophilic myocarditis? A case of Churg-Strauss syndrome diagnosed during acute heart failure.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare multisystem disorder; cardiac involvement may include eosinophilic myocarditis. A 67-year-old woman presented with 1-week history of dyspnoea and orthopnoea. She had a history of adult-onset asthma and peripheral eosinophilia. The investigations showed T-wave inversion on lateral leads, peripheral eosinophilia, elevated troponin and BNP values, and severe biventricular systolic dysfunction with diffuse hypokinesia and apical akinesia. Computed tomography excluded coronary disease and showed bilateral basal ground-glass opacities, air-space consolidation, and bilateral reticular-nodular pattern. Cardiac magnetic resonance findings were compatible with active myocardial inflammation. An endomyocardial biopsy (EMB) confirmed the diagnosis of eosinophilic myocarditis, and a therapy with oral corticosteroids and heart failure medications was started.

A case of myopericarditis recurrence after third dose of BNT162b2 vaccine against SARS-CoV-2 in a young subject: link or causality?

The rate of post-vaccine myocarditis is being studied from the beginning of the massive vaccination campaign against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although a direct cause-effect relationship has been described, in most cases, the vaccine pathophysiological role is doubtful. Moreover, it is not quite as clear as having had a previous myocarditis could be a risk factor for a post-vaccine disease relapse. A 27-year-old man presented to the emergency department for palpitations and pericardial chest pain radiated to the upper left limb, on the 4th day after the third dose of BNT162b2 vaccine. He experienced a previous myocarditis 3 years before, with full recovery and no other comorbidities. Electrocardiogram showed normal atrioventricular conduction, incomplete right bundle branch block, and diffuse ST-segment elevation. A cardiac echo showed lateral wall hypokinesis with preserved ejection fraction. Troponin-T was elevated (160 ng/L), chest X-ray was normal, and the SARS-CoV-2 molecular buffer was negative. High-dose anti-inflammatory therapy with ibuprofen and colchicine was started; in the 3rd day high-sensitivity Troponin I reached a peak of 23000 ng/L. No heart failure or arrhythmias were observed. A cardiac magnetic resonance was performed showing normal biventricular systolic function and abnormal tissue characterization suggestive for acute non-ischaemic myocardial injury (increased native T1 and T2 values, increased signal intensity at T2-weighted images and late gadolinium enhancement, all findings with matched subepicardial distribution) at the level of mid to apical septal, anterior, and anterolateral walls. A left ventricular electroanatomic voltage mapping was negative (both unipolar and bipolar), while the endomyocardial biopsy showed a picture consistent with active myocarditis. The patient was discharged in good clinical condition, on bisoprolol 1.25 mg, ramipril 2.5 mg, ibuprofen 600 mg three times a day, colchicine 0.5 mg twice a day. We presented the case of a young man with history of previous myocarditis, admitted with a non-complicated acute myopericarditis relapse occurred 4 days after SARS-CoV-2 vaccination (3rd dose). Despite the observed very low incidence of cardiac complications following BNT162b2 administration, and the lack of a clear proof of a direct cause-effect relationship, we think that in our patient this link can be more than likely. In the probable need for additional SARS-CoV-2 vaccine doses in the next future, studies addressing the risk-benefit balance of this subset of patient are warranted. We described a multidisciplinary management of a case of myocarditis recurrence after the third dose of SARS-CoV-2 BNT162b2 vaccine.

Long-Term Outcomes of Near-Zero Radiation Ablation of Paroxysmal Supraventricular Tachycardia: A Comparison With Fluoroscopy-Guided Approach.

OBJECTIVES: This study aimed to assess the long-term outcomes of minimally fluoroscopic approach (MFA) compared with conventional fluoroscopic ablation (ConvA) in terms of recurrences of arrhythmia and long-term complications. BACKGROUND: Catheter ablation (CA) of supraventricular tachycardia (SVT) with an MFA, under the guidance of electroanatomic mapping (EAM) systems, results in a significant reduction in exposure to ionizing radiations without impairing acute procedural success and complication rate. However, data regarding long-term outcomes of MFA compared with ConvA are lacking. METHODS: This is a retrospective observational study. All patients undergoing MFA CA of SVT (atrioventricular nodal re-entrant tachycardia and atrioventricular re-entrant tachycardia) between 2010 and 2015 were enrolled and were compared with matched subjects (1 MFA: 2 ConvA) undergoing ConvA during the same period. The 2 co-primary outcomes were recurrence of arrhythmias and long-term complications. RESULTS: A total of 618 patients (mean age 38 ± 15 years, 60% female) were enrolled. MFA included 206 patients, whereas 412 were treated with ConvA. Acute success (99% vs. 97%; p = 0.10) and acute complications (2.4% vs. 5.3%; p = 0.14) were similar in the 2 groups. During a median follow-up of 4.4 years, 5.9% of patients experienced recurrence of arrhythmias. At multivariate analysis, ConvA (hazard ratio [HR]: 3.03) and procedural success (HR: 0.10) were independently associated with recurrence of arrhythmias. Late complications (i.e., advance atrioventricular block and need for pacemaker implantation) occurred more frequently in ConvA (3.4% vs. 0.5%; p = 0.03) compared with MFA. CONCLUSIONS: CA guided by EAM systems with MFA provided better long-term results and reduced risk of complications compared with ConvA.

Acute outcome after a single cryoballoon ablation: Comparison between Arctic Front Advance and Arctic Front Advance PRO.

BACKGROUND: The novel fourth-generation cryoballoon (CB4) potentially allows for enhanced catheter maneuverability and more frequent capture of pulmonary vein (PV) potentials which can be used to monitor real-time PV isolation (PVI). The aim of our study is to compare the acute procedural endpoints between the CB4 and second-generation cryoballoon (CB2). METHODS: A single-center retrospective chart review was used to examine 50 consecutive patients with drug-refractory atrial fibrillation undergoing CB4-based PVI. Procedural data and acute success of these patients were compared to 50 propensity-matched controls who underwent cryoballoon ablation procedure using CB2. RESULTS: Procedures performed with the CB4 showed significant shorter fluoroscopy time (14.8 ± 5.5 vs 18.0 ± 6.5 minutes, P = .04), shorter procedure time (58.3 ± 15.7 vs 65.3 ± 21 minutes, P = .13), and shorter total ablation time (10.8 ± 1.5 vs 13.8 ± 1.9 minutes, P = .42). The real-time PVI visualization rate was 33.3% in the CB2 group and 74.7% in the CB4 group (P < .001). CB4 was correlated to significant increase of acute real-time recordings with regard to all the single PV (left superior PV: 58% vs 84%, P = .02; left inferior PV: 26% vs 71%, P = .001; right superior PV 29% vs 61%, P = .01; and right inferior PV 19% vs 58%, P = .002). CONCLUSION: The CB4 was more often able to capture real-time recordings of PV potentials and the subsequent acute PV isolation.

Cryoballoon pulmonary vein ablation and left atrial appendage closure combined procedure: A long-term follow-up analysis.

BACKGROUND: The combined left atrial appendage closure (LAAC) and cryoenergy pulmonary vein isolation (PVI) procedure has been proven safe and effective in managing stroke in patients with nonvalvular atrial fibrillation (AF), although most data refer to procedures performed using radiofrequency as the main energy source. OBJECTIVE: The purpose of this study was to evaluate long-term follow-up of patients with AF undergoing concomitant LAAC and cryoenergy PVI. METHODS: Patients undergoing LAAC and cryoballoon PVI at our institution were enrolled. At 3, 6, and 24 months from the index procedure, we determined the atrial arrhythmia recurrence rate, the extent of LAAC, and the rate of cerebrovascular/bleeding events. RESULTS: Forty-nine patients (mean age 69 ± 8 years; 32/49 (67%) men; CHA2DS2-VASc score 2.8 ± 1.2; HAS-BLED score 3 ± 1) with a guideline-recommended LAAC indication were included. Acute PVI and complete LAAC were achieved in 100% of patients. All patients completed at least 24 months of follow-up. At 8 weeks and 6 months, complete or satisfactory (<5 mm leak) LAAC rates were achieved in 40 (82%) and 9 (18%) and in 42 (86%) and 7 (14%) of patients, respectively. The overall freedom from atrial arrhythmia rate at 24 months was 29 (60%), and 45 (92%) of patients were off antithrombotic drugs. The observed annualized stroke and bleeding rates were 1% and 2%, respectively, a 71% and 60% risk reduction in comparison to event rates predicted from CHA2DS2-VASc and HAS-BLED scores. CONCLUSION: Concomitant cryoballoon ablation and LAAC procedures appear safe and effective at long-term follow-up, with high antithrombotic drug withdrawal rates at 24 months.

Ablation Index as a predictor of long-term efficacy in premature ventricular complex ablation: A regional target value analysis.

BACKGROUND: The effectiveness of radiofrequency catheter ablation (RFCA) in atrial tachyarrhythmias correlates with lesion transmurality. Ablation Index (AI) is an index that incorporates contact force, time, and radiofrequency power simultaneously and is able to predict lesion size and outcomes in RFCA of atrial fibrillation. OBJECTIVE: The purpose of this study was to assess whether AI could be an acute and long-term success predictor in RFCA of premature ventricular complexes (PVCs). METHODS: One hundred forty-five patients with idiopathic outflow tract PVCs undergoing RFCA were retrospectively enrolled. The maximum and maximum AI values were calculated for each ablation site. Acute and 6-month outcomes were analyzed. Patients were divided into 3 outcome subgroups-success, acute failure, and 6-month failure-and the maximum and mean AI values were compared. RESULTS: Acute and 6-month success rates were 95% and 77%, respectively. The maximum and mean AI values were statistically higher in the success group (median of the maximum AI 630 [IQR 561-742]; median of the mean AI 489 [IQR 411-560]) than in the acute failure group (median of the maximum AI 487 [IQR 445-583]; median of the mean AI 372 [IQR 332-434]; P < .0001 for both) and the 6-month failure group (median of the maximum AI 519 [IQR 476-568]; median of the mean AI 410 [IQR 368-472]; P < .0001 for both). Both maximum and mean AI values were confirmed to be statistically higher in the success group than in the failure/6-month failure group (P = .001 and P = .04, respectively) and right ventricular free wall (P = .007 and P = .01, respectively) PVC origin subgroups. CONCLUSION: Our data support the concept that AI could be a long-term success predictor in RFCA of PVCs. However, further prospective studies are required to assess the feasibility of the AI-guided PVC ablation approach.

Lesion index: a novel guide in the path of successful pulmonary vein isolation.

PURPOSE: Previous studies indicate force time integral (FTI) as a radiofrequency (RF) lesion quality marker, while not considering power supply. Tacticath™ Quartz catheter provides Lesion index (LSI), a lesion quality marker derived by contact force (CF), power supply, and RF time combined. Our aim is to assess LSI and FTI correlation and a LSI-related cutoff of atrial fibrillation (AF) recurrences 12 months after pulmonary vein isolation (PVI). METHODS: We retrospectively enrolled 37 patients who underwent RF ablation using Tacticath™ Quartz catheter. AF recurrence rate was evaluated 3, 6, and 12 months after PVI procedure. RESULTS: AF recurrence was detected in 32% of patients. FTI mean value was significantly lower in left superior pulmonary vein (LSPV: 256 ± 86 gs vs 329 ± 117 gs, p = 0.05) and right inferior pulmonary vein (RIPV: 253 ± 128 gs vs 394 ± 123 gs p = 0.006) in patients with AF recurrences; no significant differences were found in right superior pulmonary vein (RSPV) and left inferior pulmonary vein (LIPV). LSI instead was significantly higher for all veins in patients without AF recurrences: LSPV (5.2 ± 0.7 vs 4.6 ± 0.8, p = 0.03), LIPV (5.0 ± 0.8 vs 4.5 ± 0.6, p = 0.04), RSPV (5.5 ± 0.6 vs 5.1 ± 0.6, p = 0.05), and RIPV (5.5 ± 0.7 vs 4.7 ± 0.8, p = 0.006). Receiver operator characteristic curve suggests 5.3 as LSI overall cutoff value predicting freedom from disease at 1-year follow-up. CONCLUSIONS: Our preliminary data suggest that a LSI mean value higher than 5.3 can be considered a good predictor of AF freedom at 1-year follow-up.

X-Ray Exposure in Cardiac Electrophysiology: A Retrospective Analysis in 8150 Patients Over 7 Years of Activity in a Modern, Large-Volume Laboratory.

BACKGROUND: Only a few studies have systematically evaluated fluoroscopy data of electrophysiological and device implantation procedures. Aims of this study were to quantify ionizing radiation exposure for electrophysiological/device implantation procedures in a large series of patients and to analyze the x-ray exposure trend over years and radiation exposure in patients undergoing atrial fibrillation ablation considering different technical aspects. METHODS AND RESULTS: We performed a retrospective analysis of all electrophysiological/device implantation procedures performed during the past 7 years in a modern, large-volume laboratory. We reported complete fluoroscopy data on 8150 electrophysiological/device implantation procedures (6095 electrophysiological and 2055 device implantation procedures); for each type of procedure, effective dose and lifetime attributable risk of cancer incidence and mortality were calculated. Over the 7-year period, we observed a significant trend reduction in fluoroscopy time, dose area product, and effective dose for all electrophysiological procedures (P<0.001) and a not statistically significant trend reduction for device implantation procedures. Analyzing 2416 atrial fibrillation ablations, we observed a significant variability of fluoroscopy time, dose area product and effective dose among 7 different experienced operators (P<0.0001) and a significant reduction of fluoroscopy use over time (P<0.0001) for all of them. Considering atrial fibrillation ablation techniques, fluoroscopy time was not different (P = 0.74) for radiofrequency catheter ablation in comparison with cryoablation, though cryoablation was still associated with higher dose area product and effective dose values (P<0.001). CONCLUSIONS: Electrophysiological procedures involve a nonnegligible x-ray use, leading to an increased risk of malignancy. Awareness of radiation-related risk, together with technological advances, can successfully optimize fluoroscopy use.

Concomitant cryoballoon ablation and percutaneous closure of left atrial appendage in patients with atrial fibrillation.

AIMS: Pulmonary veins (PVs) isolation is the cornerstone of atrial fibrillation (AF) ablation and can be achieved either by conventional radiofrequency ablation or by cryoenergy. Left atrial appendage (LAA) closure has been proposed as alternative treatment to vitamin K antagonists (VKA). We aimed to evaluate the feasibility of combining cryoballoon (CB) ablation and LAA occlusion in patients with AF and a high thromboembolic risk or contraindication to antithrombotic therapy. METHODS AND RESULTS: Thirty-five patients (28 males, 74 ± 2 years) underwent CB ablation. Left atrial appendage occlusion was carried out by using two occluder devices (Amplatz Cardiac Plug, ACP, St. Jude Medical, MN, USA, in 25 patients; Watchman, Boston Scientific, MA, USA, in 10 patients). Thirty patients (86%) had previous stroke/TIA episodes, 6 patients (17%) had major bleeding while on VKA therapy, and 7 patients (20%) had inherited bleeding disorders. Over the follow-up (24 ± 12 months), atrial arrhythmias recurred in 10 (28%) patients. Thirty patients (86%) had complete sealing; 5 patients (14%) showed a residual flow (<5 mm) at first transoesophageal echocardiography (TEE) check, while at 1-year TEE residual flow was detected in 3 patients. In 13 patients (37%), VKA therapy was immediately discontinued. Six patients (17%) received novel oral anticoagulants treatment and then discontinued 3 months thereafter. No device-related complications or clinical thromboembolic events occurred. CONCLUSION: Combined CB ablation and LAA closure using different devices appears to be feasible in patients with non-valvular AF associated with high risk of stroke or contraindication to antithrombotic treatment.

Comparison between First- and Second-Generation Cryoballoon for Paroxysmal Atrial Fibrillation Ablation.

Introduction. Cryoballoon (CB) ablation has emerged as a novel treatment for pulmonary vein isolation (PVI) for patients with paroxysmal atrial fibrillation (PAF). The second-generation Arctic Front Advance (ADV) was redesigned with technical modifications aiming at procedural and outcome improvements. We aimed to compare the efficacy of the two different technologies over a long-term follow-up. Methods. A total of 120 patients with PAF were enrolled. Sixty patients underwent PVI using the first-generation CB and 60 patients with the ADV catheter. All patients were evaluated over a follow-up period of 2 years. Results. There were no significant differences between the two groups of patients. Procedures performed with the first-generation CB showed longer fluoroscopy time (36.3 ± 16.8 versus 14.2 ± 13.5 min, resp.; p = 0.00016) and longer procedure times as well (153.1 ± 32 versus 102 ± 24.8 min, resp.; p = 0.019). The overall long-term success was significantly different between the two groups (68.3 versus 86.7%, resp.; p = 0.017). No differences were found in the lesion areas of left and right PV between the two groups (resp., p = 0.61 and 0.57). There were no significant differences in procedural-related complications. Conclusion. The ADV catheter compared to the first-generation balloon allows obtaining a significantly higher success rate after a single PVI procedure during the long-term follow-up. Fluoroscopy and procedural times were significantly shortened using the ADV catheter.

Usefulness of intracardiac echocardiography during pulmonary vein isolation with the novel multipolar irrigated ablation catheter (nMARQ™).

BACKGROUND: Previous studies reported the usefulness of an irrigated circular radiofrequency ablation catheter (nMARQ(TM), Biosense Webster) for pulmonary vein isolation (PVI). We evaluated the role of intracardiac echocardiography (ICE) to optimize the manipulation of nMARQ(TM) catheter. METHODS: Thirty-seven patients (pts), (mean age 55 ± 12 years; 28 males) were enrolled to perform PVI. All pts underwent PVI with the nMARQ(TM) catheter. In 20 pts (group 1), we utilized ICE to guide nMARQ(TM) catheter positioning at the PV ostia; in the other 17 pts (group 2), nMARQ(TM) catheter was positioned at the PV ostia guided by fluoroscopy and TissueConnect(TM) technology. RESULTS: Radiofrequency (RF) applications were significantly lower in group 1 compared to group 2 [left PVs: 6 (range 3 to 12) in group 1 and 12 (range 5 to 16) in group 2 (p < 0.001); right PVs: 7 (range 4 to 14) in group 1 and 10 (range 5 to 16) in group 2 (p = 0.04)]; similarly regarding the time of RF delivery [left PVs: 318 ± 194 s in group 1 vs. 542 ± 104 s in group 2 (p < 0.001); right PVs: 410 ± 270 s in group 1 vs. 550 ± 156 s in group 2 (p = 0.05)]. Fluoroscopy time (23 ± 9 min vs. 28 ± 5 min; p = 0.05), procedural time (83 ± 23 min vs. 160 ± 42 min; p < 0.001), and radiation dose (109 ± 20 Gy/cm(2) vs. 127 ± 29 Gy/cm(2); p = 0.04) were significantly lower in group 1 compared to group 2. CONCLUSION: ICE might be a useful tool to guide nMARQ(TM) catheter position in the left atrium during atrial fibrillation (AF) ablation procedures.

Idiopathic Ventricular Tachycardia: Transcatheter Ablation or Antiarrhythmic Drugs?

INTRODUCTION: Ventricular tachycardia or frequent premature ventricular contractions (PVCs) can occur in the absence of any detectable structural heart disease. In this clinical setting, these arrhythmias are termed idiopathic. Usually, they carry a benign prognosis and any potential ablative intervention is carried out if patients are highly symptomatic or, more importantly, if frequent ventricular arrhythmias can lead to ventricular dysfunction. METHODS: In this paper, different forms of idiopathic ventricular tachycardia are reviewed. Outflow tract ventricular tachycardia from the right ventricle is the most frequent form of the so-called idiopathic ventricular tachycardia. Other forms of idiopathic ventricular arrhythmias include ventricular tachycardia/PVCs arising from tricuspid annulus, from the mitral annulus, inter-fascicular ventricular tachycardia and papillary muscle ventricular tachycardia. When interventional treatment is deemed necessary, detailed mapping ( earliest activation during VT/PVC, pace mapping ) is crucial as to identify the successful ablation site. Catheter ablation more than antiarrhythmic drug treatment is usually highly effective in eliminating idiopathic ventricular arrhythmias and providing prevention of recurrence. CONCLUSIONS: Idiopathic VTs are not considered life-threatening arrhythmias and, prevention of recurrences is often achieved by means of catheter ablation that provides an improvement of quality of life. The overall acute success rate of catheter ablation is about 85-90% with a long-term prevention of arrhythmia recurrence of about 75-80%. It is advisable that the procedure is carried out by electrophysiologists with expertise in VT catheter ablation and extensive knowledge of cardiac anatomy as to ensure a high success rate and reduce the likelihood of major complications.

Simultaneous assessment of contact pressure and local electrical coupling index using robotic navigation.

PURPOSE: Contact with cardiac tissue is a determinant of lesion efficacy during atrial fibrillation (AF) ablation. The Sensei®X Robotic Catheter System (Hansen Medical, CA) has been validated for contact force sensing. The electrical coupling index (ECI) from the EnSite Contact™ system (St. Jude Medical, MN) has been validated as an indicator of tissue contact. We aimed at analyzing ECI behavior during radiofrequency (RF) pulses maintaining a stable contact through the robotic navigation contact system. METHODS: In 15 patients (age, 59 ± 12) undergoing AF ablation, pulmonary vein (PV) isolation was guided by the Sensei®X System, employing the Contact™ catheter. RESULTS: During the procedure, we assessed ECI changes associated with adequate contact based on the IntelliSense® force-sensing technology (Hansen Medical, CA. Baseline contact (27 ± 8 g/cm(2)) ECI value was 99 ± 13, whereas ECI values in a noncontact site (0 g/cm(2)) and in a light contact site (1-10 g/cm(2)) were respectively 66 ± 12 and 77 ± 10 (p < 0.0001). Baseline contact ECI values were not different depending on AF presentation (paroxysmal AF, 98 ± 9; persistent AF, 100 ± 9) or on cardiac rhythm (sinus rhythm, 97 ± 7; AF,101 ± 10). In all PVs, ECI was significantly reduced during and after ablation (ECI during RF, 56 ± 15; ECI after RF, 72 ± 16; p < 0.001). A mean reduction of 32.2% during RF delivery and 25.4% immediately after RF discontinuation compared with baseline ECI was observed. CONCLUSIONS: Successful PV isolation is associated with a significant decrease in ECI of at least 20 %. This may be used as a surrogate marker of effective lesion in AF ablation.

The Growing Culture Of A Minimally Fluoroscopic Approach In Electrophysiology Lab.

Most of interventional procedures in cardiology are carried out under fluoroscopic imaging guidance. Besides other peri-interventional risks, radiation exposure should be considered for its stochastic (inducing malignancy) and deterministic effects on health (tissue reactions like erythema, hair loss and cataracts). In this article we analized the radiation risk from cardiovascular imaging to both patients and medical staff and discusses how customize the X-ray system and how to implement shielding measures in the cath lab. Finally, we reviewed the most recent developments and the latest findings in catheter navigation and 3D electronatomical mapping systems that may help to reduce patient and operator exposure.

New Imaging Technologies To Characterize Arrhythmic Substrate.

The cornerstone of the new imaging technologies to treat complex arrhythmias is the electroanatomic (EAM) mapping. It is based on tissue characterization and in particular on determination of low potential region and dense scar definition. Recently, the identification of fractionated isolated late potentials increased the specificity of the information derived from EAM. In addition, non-invasive tools and their integration with EAM, such as cardiac magnetic resonance imaging and computed tomography scanning, have been shown to be helpful to characterize the arrhythmic substrate and to guide the mapping and the ablation. Finally, intracardiac echocardiography, known to be useful for several practical uses in the setting of electrophysiological procedures, it has been also demonstrated to provide important informations about the anatomical substrate and may have potential to identify areas of scarred myocardium.

Role of Intracardiac echocardiography in Atrial Fibrillation Ablation.

In the recent years, several new evidences support catheter-based ablation as a treatment modality of atrial fibrillation (AF). Based on a plenty of different applications, intracardiac echocardiography (ICE) is now a well-established technology in complex electrophysiological procedures, in particular in AF ablation. ICE contributes to improve the efficacy and safety of such procedures defining the anatomical structures involved in ablation procedures and monitoring in real time possible complications. In particular ICE allows: a correct identification of the endocardial structures; a guidance of transseptal puncture; an assessment of accurate placement of the circular mapping catheter; an indirect evaluation of evolving lesions during radiofrequency (RF) energy delivery via visualization of micro and macrobubbles tissue heating; assessment of catheter contact with cardiac tissues. Recently, also the feasibility of the integration of electroanatomical mapping (EAM) and intracardiac echocardiography has been demonstrated, combining accurate real time anatomical information with electroanatomical data. As a matter of fact, different techniques and ablation strategies have been developed throughout the years. In the setting of balloon-based ablation systems, recently adopted by an increasing number of centers, ICE might have a role in the choice of appropriate balloon size and to confirm accurate occlusion of pulmonary veins. Furthermore, in the era of minimally fluoroscopic ablation, ICE has successfully provided a contribute in reducing fluoroscopy time. The purpose of this review is to summarize the current applications of ICE in catheter based ablation strategies of atrial fibrillation, focusing-on electronically phased-array ICE.

Prevalence and clinical significance of collateral findings detected by chest computed tomography in patients undergoing atrial fibrillation ablation.

AIMS: Chest computed tomography (CT) scanning is increasingly used as an imaging technique in patients undergoing atrial fibrillation (AF) catheter ablation. Chest CT scans visualize organs other than the heart and collateral findings may be identified incidentally. Our study aims to assess the prevalence and clinical relevance of such collateral findings in patients undergoing AF ablation. METHODS AND RESULTS: One hundred and seventy-three patients (127 males, age 59 ± 10 years) underwent chest CT scan for image integration in AF ablation. Collateral findings from visualized thoracic and upper abdominal organs were collected. Findings that required further investigations or treatment according to current guidelines were considered as clinically significant. A total of 164 collateral findings were identified in 97 (56%) patients, and most patients showed abnormalities of the lungs (67 patients, 39%). Forty-nine (28%) patients had clinically significant findings needing further investigation and 17 (10%) of them required specific treatments, including three cases (1.7 %) of lung malignancy. CONCLUSIONS: Chest CT images acquired for integration in AF ablation should be read thoroughly as they may serve as a screening tool for otherwise unrecognized clinically significant conditions of the heart, lungs, or other visualized organs.