Diagnosis and Management of Paroxysmal Supraventricular Tachycardia.

Importance: Paroxysmal supraventricular tachycardia (PSVT), defined as tachyarrhythmias that originate from or conduct through the atria or atrioventricular node with abrupt onset, affects 168 to 332 per 100 000 individuals. Untreated PSVT is associated with adverse outcomes including high symptom burden and tachycardia-mediated cardiomyopathy. Observations: Approximately 50% of patients with PSVT are aged 45 to 64 years and 67.5% are female. Most common symptoms include palpitations (86%), chest discomfort (47%), and dyspnea (38%). Patients may rarely develop tachycardia-mediated cardiomyopathy (1%) due to PSVT. Diagnosis is made on electrocardiogram during an arrhythmic event or using ambulatory monitoring. First-line acute therapy for hemodynamically stable patients includes vagal maneuvers such as the modified Valsalva maneuver (43% effective) and intravenous adenosine (91% effective). Emergent cardioversion is recommended for patients who are hemodynamically unstable. Catheter ablation is safe, highly effective, and recommended as first-line therapy to prevent recurrence of PSVT. Meta-analysis of observational studies shows single catheter ablation procedure success rates of 94.3% to 98.5%. Evidence is limited for the effectiveness of long-term pharmacotherapy to prevent PSVT. Nonetheless, guidelines recommend therapies including calcium channel blockers, ß-blockers, and antiarrhythmic agents as management options. Conclusion and Relevance: Paroxysmal SVT affects both adult and pediatric populations and is generally a benign condition. Catheter ablation is the most effective therapy to prevent recurrent PSVT. Pharmacotherapy is an important component of acute and long-term management of PSVT.

One-year mortality and causes of death after stereotactic radiation therapy for refractory ventricular arrhythmias: A systematic review and pooled analysis.

Patients treated with cardiac stereotactic body radiation therapy (radioablation) for refractory ventricular arrhythmias are patients with advanced structural heart disease and significant comorbidities. However, data regarding 1-year mortality after the procedure are scarce. This systematic review and pooled analysis aimed at determining 1-year mortality after cardiac radioablation for refractory ventricular arrhythmias and investigating leading causes of death in this population. MEDLINE/EMBASE databases were searched up to January 2023 for studies including patients undergoing cardiac radioablation for the treatment of refractory ventricular arrhythmias. Quality of included trials was assessed using the NIH Tool for Case Series Studies (PROSPERO CRD42022379713). A total of 1,151 references were retrieved and evaluated for relevance. Data were extracted from 16 studies, with a total of 157 patients undergoing cardiac radioablation for refractory ventricular arrhythmias. Pooled 1-year mortality was 32 % (95 %CI: 23-41), with almost half of the deaths occurring within three months after treatment. Among the 157 patients, 46 died within the year following cardiac radioablation. Worsening heart failure appeared to be the leading cause of death (52 %), although non-cardiac mortality remained substantial (41 %) in this population. Age≥70yo was associated with a significantly higher 12-month all-cause mortality (p<0.022). Neither target volume size nor radiotherapy device appeared to be associated with 1-year mortality (p = 0.465 and p = 0.199, respectively). About one-third of patients undergoing cardiac stereotactic body radiation therapy for refractory ventricular arrhythmias die within the first year after the procedure. Worsening heart failure appears to be the leading cause of death in this population.

50-W vs 40-W During High-Power Short-Duration Ablation for Paroxysmal Atrial Fibrillation: A Multicenter Prospective Study.

BACKGROUND: High-power short-duration (HPSD) radiofrequency ablation of atrial fibrillation (AF) increases first-pass pulmonary vein isolation (PVI) and freedom from atrial arrhythmias while decreasing procedural time. However, the optimal power setting in terms of safety and efficacy has not been determined. OBJECTIVES: This study compared the procedural characteristics and clinical outcomes of 50-W vs 40-W during HPSD ablation of paroxysmal AF. METHODS: Patients from the REAL-AF prospective multicenter registry (Real-World Experience of Catheter Ablation for Treatment of Symptomatic Paroxysmal and Persistent Atrial Fibrillation) undergoing HPSD ablation of paroxysmal AF, either using 50-W or 40-W, were included. The primary efficacy outcome was freedom from all-atrial arrhythmias. The primary safety outcome was the occurrence of any procedural complication at 12 months. Secondary outcomes included procedural characteristics, AF-related symptoms, and the occurrence of transient ischemic attack or stroke at 12 months. RESULTS: A total of 383 patients were included. Freedom from all-atrial arrhythmias at 12 months was 80.7% in the 50-W group and 77.3% in the 40-W group (Log-rank P = 0.387). The primary safety outcome occurred in 3.7% of patients in the 50-W group vs 2.8% in the 40-W group (P = 0.646). The 50-W group had a higher rate of first-pass PVI (82.3% vs 76.2%; P = 0.040) as well as shorter procedural (67 minutes [IQR: 54-87.5 minutes] vs 93 minutes [IQR: 80.5-111 minutes]; P < 0.001) and radiofrequency ablation times (15 minutes [IQR: 11.4-20 minutes] vs 27 minutes [IQR: 21.5-34.6 minutes]; P < 0.001) than the 40-W group. CONCLUSIONS: There was no significant difference in freedom from all-atrial arrhythmias or procedural safety outcomes between 50-W and 40-W during HPSD ablation of paroxysmal AF. The use of 50-W was associated with a higher rate of first-pass PVI as well as shorter procedural times.

Chinese expert consensus on the construction of the fluoroless cardiac electrophysiology laboratory and related techniques.

Transcatheter radiofrequency ablation has been widely introduced for the treatment of tachyarrhythmias. The demand for catheter ablation continues to grow rapidly as the level of recommendation for catheter ablation. Traditional catheter ablation is performed under the guidance of X-rays. X-rays can help display the heart contour and catheter position, but the radiobiological effects caused by ionizing radiation and the occupational injuries worn caused by medical staff wearing heavy protective equipment cannot be ignored. Three-dimensional mapping system and intracardiac echocardiography can provide detailed anatomical and electrical information during cardiac electrophysiological study and ablation procedure, and can also greatly reduce or avoid the use of X-rays. In recent years, fluoroless catheter ablation technique has been well demonstrated for most arrhythmic diseases. Several centers have reported performing procedures in a purposefully designed fluoroless electrophysiology catheterization laboratory (EP Lab) without fixed digital subtraction angiography equipment. In view of the lack of relevant standardized configurations and operating procedures, this expert task force has written this consensus statement in combination with relevant research and experience from China and abroad, with the aim of providing guidance for hospitals (institutions) and physicians intending to build a fluoroless cardiac EP Lab, implement relevant technologies, promote the standardized construction of the fluoroless cardiac EP Lab.

High-Frequency Low-Tidal Volume Ventilation Improves Long-Term Outcomes in AF Ablation: A Multicenter Prospective Study.

BACKGROUND: High-frequency, low-tidal-volume (HFLTV) ventilation is a safe and simple strategy to improve catheter stability and first-pass isolation during pulmonary vein (PV) isolation. However, the impact of this technique on long-term clinical outcomes has not been determined. OBJECTIVES: This study sought to assess acute and long-term outcomes of HFLTV ventilation compared with standard ventilation (SV) during radiofrequency (RF) ablation of paroxysmal atrial fibrillation (PAF). METHODS: In this prospective multicenter registry (REAL-AF), patients undergoing PAF ablation using either HFLTV or SV were included. The primary outcome was freedom from all-atrial arrhythmia at 12 months. Secondary outcomes included procedural characteristics, AF-related symptoms, and hospitalizations at 12 months. RESULTS: A total of 661 patients were included. Compared with those in the SV group, patients in the HFLTV group had shorter procedural (66 [IQR: 51-88] minutes vs 80 [IQR: 61-110] minutes; P < 0.001), total RF (13.5 [IQR: 10-19] minutes vs 19.9 [IQR: 14.7-26.9] minutes; P < 0.001), and PV RF (11.1 [IQR: 8.8-14] minutes vs 15.3 [IQR: 12.4-20.4] minutes; P < 0.001) times. First-pass PV isolation was higher in the HFLTV group (66.6% vs 63.8%; P = 0.036). At 12 months, 185 of 216 (85.6%) in the HFLTV group were free from all-atrial arrhythmia, compared with 353 of 445 (79.3%) patients in the SV group (P = 0.041). HLTV was associated with a 6.3% absolute reduction in all-atrial arrhythmia recurrence, lower rate of AF-related symptoms (12.5% vs 18.9%; P = 0.046), and hospitalizations (1.4% vs 4.7%; P = 0.043). There was no significant difference in the rate of complications. CONCLUSIONS: HFLTV ventilation during catheter ablation of PAF improved freedom from all-atrial arrhythmia recurrence, AF-related symptoms, and AF-related hospitalizations with shorter procedural times.

The effect of ionizing radiation through cardiac stereotactic body radiation therapy on myocardial tissue for refractory ventricular arrhythmias: A review.

Cardiac stereotactic body radiation therapy (cSBRT) is a non-invasive treatment modality that has been recently reported as an effective treatment for ventricular arrhythmias refractory to medical therapy and catheter ablation. The approach leverages tools developed and refined in radiation oncology, where experience has been accumulated in the treatment of a wide variety of malignant conditions. However, important differences exist between rapidly dividing malignant tumor cells and fully differentiated myocytes in pathologically remodeled ventricular myocardium, which represent the respective radiation targets. Despite its initial success, little is known about the radiobiology of the anti-arrhythmic effect cSBRT. Pre-clinical data indicates a late fibrotic effect of that appears between 3 and 4 months following cSBRT, which may result in conduction slowing and block. However, there is clear clinical evidence of an anti-arrhythmic effect of cSBRT that precedes the appearance of radiation induced fibrosis for which the mechanism is unclear. In addition, the data to date suggests that even the late anti-arrhythmic effect of cSBRT is not fully attributable to radiation.-induced fibrosis. Pre-clinical data has identified upregulation of proteins expected to result in both increased cell-to-cell coupling and excitability in the early post cSBRT period and demonstrated an associated increase in myocardial conduction velocity. These observations indicate a complex response to radiotherapy and highlight the lack of clarity regarding the different stages of the anti-arrhythmic mechanism of cSBRT. It may be speculated that in the future cSBRT therapy could be planned to deliver both early and late radiation effects titrated to optimize the combined anti-arrhythmic efficacy of the treatment. In addition to these outstanding mechanistic questions, the optimal patient selection, radiation modality, radiation dose and treatment planning strategy are currently being investigated. In this review, we consider the structural and functional effect of radiation on myocardium and the possible anti-arrhythmic mechanisms of cSBRT. Review of the published data highlights the exciting prospects for the development of knowledge and understanding in this area in which so many outstanding questions exist.

Cost of cardiac stereotactic body radioablation therapy versus catheter ablation for treatment of ventricular tachycardia.

AIMS: To compare the cost of cardiac stereotactic body radioablation therapy (SBRT) versus catheter ablation for treating ventricular tachycardia (VT). BACKGROUND: Cardiac SBRT is a novel way of treating refractory VT that may be less costly than catheter ablation, owing to its noninvasive, outpatient nature. However, the true costs of either procedure are not well described, which could help inform a more appropriate reimbursement for cardiac SBRT than simply cross-indexing existing procedural rates. METHODS: Process maps were derived for the full patient care cycle of both procedures using time-driven activity-based costing. Step-by-step timestamps were collected prospectively from a 10-patient SBRT cohort and retrospectively from a 59-patient catheter ablation cohort. Individual costs were estimated by multiplying timestamps with capacity cost rates (CCRs) for personnel, space, equipment, consumable, and indirect resources. These were summed into total cost, which for cardiac SBRT was compared with current catheter ablation and single-fraction lung SBRT reimbursements, both potential reference rates for cardiac SBRT. RESULTS: The direct and total procedural costs of cardiac SBRT ($7549 and $10,621) were 49% and 54% less than those of VT ablation ($14,707 and $23,225). These costs were significantly different from current reimbursement for catheter ablation ($22,692) and lung SBRT ($6329). After including hospitalization expenses (≥$15,000), VT ablation costs at least $27,604 more to furnish than cardiac SBRT. CONCLUSIONS: Time-driven activity-based costing (TDABC) can be a helpful tool for assessing healthcare costs, including novel treatment approaches. In addition to its clinical benefits, cardiac SBRT may provide significant cost reduction opportunities for treatment of VT.

Non-invasive ablation of arrhythmias with stereotactic ablative radiotherapy.

Stereotactic ablative radiotherapy (SABR), or stereotactic body radiotherapy (SBRT), has recently been applied in the field of arrhythmia management. It has been most widely assessed in the treatment of ventricular tachycardia (VT) but may also have potential in the treatment of other arrhythmias as well, often termed stereotactic arrhythmia radiotherapy (STAR). The non-invasive delivery of treatment for VT has the potential to spare an often physiologically vulnerable group of patients the burden of long catheter ablation procedures with the potential for prolonged periods of hemodynamic instability. Cardiac SABR also has the capacity to direct ablative therapy at substrate that is inaccessible using current transchatheter techniques. For these reasons cardiac SABR has generated significant enthusiasm as an emerging treatment modality for VT. We consider in review the pre-clinical data pertaining to the use of SABR in cardiac tissue and recent clinical evidence regarding the application of SABR in the field of arrhythmia management.

Substrate Modification Using Stereotactic Radioablation to Treat Refractory Ventricular Tachycardia in Patients With Ischemic Cardiomyopathy.

OBJECTIVES: This study aimed to determine the feasibility of using radioablation for arrhythmogenic a substrate modification. BACKGROUND: Stereotactic body radiation therapy (SBRT) is a promising therapy for ventricular tachycardia (VT) refractory to catheter ablation. METHODS: A total of 6 male patients (median age 72 years) with ischemic cardiomyopathy (left ventricular ejection fraction 20% [interquartile range (IQR): 16%-25%]) and VT refractory to antiarrhythmic medications and catheter ablations underwent SBRT to extensive scar substrate. In addition to electroanatomical mapping, 5 of 6 patients had computed tomography segmentation using MUSIC (IHU Liryc, Univ. Bordeaux and Inria Sophia Antipolis, France). Regions of wall thinning <5 mm, calcification, and intramyocardial fat were targeted for radioablation at 25 Gy. RESULTS: The median planning target volume was 319 (IQR: 280-330) mL. Device-treated or sustained VT episodes were not significantly reduced by radioablation (median 42 [IQR: 19-269] to 29 [IQR: 0-81]; P = 0.438). However, a reduction in device shocks was observed from 12 (IQR: 3-19) to 0 (IQR: 0-1) (P = 0.046). Over a follow-up period of 231 (IQR: 212-311) days, 3 patients died of end-stage heart failure and 3 of 6 patients had possible adverse events (heart failure exacerbation, pneumonia, and an asymptomatic pericardial effusion). CONCLUSIONS: Substrate modification using SBRT assisted by computed tomography segmentation is feasible for treatment of VT in patients with ischemic cardiomyopathy. Although a significant reduction in device shocks was observed, suboptimal VT burden reduction and significant mortality rate in this cohort of patients with advanced cardiomyopathy underscore the need to improve mechanistic understanding for antiarrhythmic effects to guide dosing and targeting of scar substrates.

Cardiac stereotactic body radiation therapy for ventricular tachycardia: Current experience and technical gaps.

INTRODUCTION: Despite advances in drug and catheter ablation therapy, long-term recurrence rates for ventricular tachycardia remain suboptimal. Cardiac stereotactic body radiotherapy (SBRT) is a novel treatment that has demonstrated reduction of arrhythmia episodes and favorable short-term safety profile in treatment-refractory patients. Nevertheless, the current clinical experience is early and limited. Recent studies have highlighted variable duration of treatment effect and substantial recurrence rates several months postradiation. Contributing to these differential outcomes are disparate approaches groups have taken in planning and delivering radiation, owing to both technical and knowledge gaps limiting optimization and standardization of cardiac SBRT. METHODS AND FINDINGS: In this report, we review the historical basis for cardiac SBRT and existing clinical data. We then elucidate the current technical gaps in cardiac radioablation, incorporating the current clinical experience, and summarize the ongoing and needed efforts to resolve them. CONCLUSION: Cardiac SBRT is an emerging therapy that holds promise for the treatment of ventricular tachycardia. Technical gaps remain, to be addressed by ongoing research and growing clincial experience.

Advantages and challenges for noninvasive atrial fibrillation ablation.

PURPOSE: Although catheter ablation is an effective therapy for atrial fibrillation (AF), risks remain and improved efficacy is desired. Stereotactic radiotherapy is a well-established therapy used to noninvasively treat malignancies with precision. We sought to evaluate stereotactic arrhythmia radioablation (STAR) as a therapeutic option for treating AF. METHODS AND RESULTS: Three cancer patients with drug refractory AF were enrolled. Planning software using 3-D CT of the left atrium was used to design a desired ablation volume encompassing antral circumferential pulmonary vein isolation, roof and floor lines to create a "box" lesion set. After planning, patients were treated in the radioablation suite. STAR was able to deliver the intended radiation dose to the target in all 3 patients. No complications were observed over a follow-up period of 24 months. One patient with paroxysmal AF died from deterioration of cancer. The autopsy revealed evidence of fibroblasts and fibrogenesis in the region of atrial tissues targeted with radioablation. In one of these patients, left atrial posterior wall electrograms recorded from the esophagus before and 3 months after STAR indicated successful electrical isolation. CONCLUSIONS: This is the first report of non-invasive radioablation of the left atrium with demonstration of successful electrical isolation. Although STAR may be safe and effective in delivering ablative energy to the left atrium, further evaluation is warranted regarding effectiveness.

Non-invasive Stereotactic Radioablation: A New Option for the Treatment of Ventricular Arrhythmias.

Ventricular tachycardia (VT) is associated with significant morbidity and mortality. Radiofrequency catheter ablation can be effective for the treatment of VT but it carries a high rate of recurrence often attributable to insufficient depth of penetration for reaching critical arrhythmogenic substrates. Stereotactic body radioablation (SBRT) is a commonly used technology developed for the non-invasive treatment of solid tumours. Recent evidence suggests that it can also be effective for the treatment of VT. It is a non-invasive procedure and it has the unique advantage of delivering ablative energy to any desired volume within the body to reach sites that are inaccessible with catheter ablation. This article summarises the pre-clinical studies that have formed the evidence base for SBRT in the heart, describes the clinical approaches for SBRT VT ablation and provides perspective on next steps for this new treatment modality.

Cardiac radioablation-A systematic review.

Failure of drugs and catheter ablation procedures for the treatment of ventricular arrhythmias is still extremely relevant. Recently, stereotactic body radiotherapy has been introduced to treat therapy refractory patients. In this systematic review (International Prospective Register of Systematic Reviews, CRD42019133212), we aimed to summarize electrophysiological and histopathological effects of radioablation in animals, patients, and extracted and perfused hearts. A systematic search was performed in OVID MEDLINE, OVID Embase, the Cochrane Central Register of Controlled Trials, Web of Science, Google Scholar, ClinicalTrials.gov, and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) from inception to September 2019. Identified records were independently screened for eligibility by 2 reviewers. Risk of bias and methodological quality were assessed using the SYRCLE, ROBINS-I, or Murad tool and tailored to the different study designs. We included 13 preclinical and 10 clinical publications. Large heterogeneity in study designs prompted a narrative synthesis approach. Baseline, (pre-)procedural details, outcome, target tissue analyses, and safety data were extracted and summarized. In animal studies evaluating electrophysiological parameters, radioablation induced a reduction in voltage/potential amplitude or bidirectional block in target areas in 93.2% of animals. Atrioventricular block (first to third degree) was induced in 78.3% of animals, and in studies evaluating ventricular arrhythmia inducibility, 75% reduction was achieved. In patients, predominantly ventricular tachycardias were targeted with >85% reduction in arrhythmia episodes during follow-up with an encouraging short-term safety profile. Preclinical and clinical evidence on the efficacy and safety of radioablation is limited in both quantity and quality. The results of radioablation for therapy refractory patients with ventricular tachycardia are promising, but further research is needed.

Stereotactic arrhythmia radioablation for refractory scar-related ventricular tachycardia.

BACKGROUND: Recently, stereotactic radiosurgery has been applied to arrhythmias (stereotactic arrhythmia radioablation [STAR]), with promising results reported in patients with refractory scar-related ventricular tachycardia (VT), a cohort with known high morbidity and mortality. OBJECTIVE: Herein, we describe our experience with STAR, detailing its early and mid- to long-term results. METHODS: This is a pilot prospective study of patients undergoing STAR for refractory scar-related VT. The anatomical target for radioablation was defined on the basis of the clinical VT morphology, electroanatomic mapping, and study-specific preprocedural imaging with cardiac computed tomography. The target volume was treated with a prescription radiation dose of 25 Gy delivered in a single fraction by CyberKnife in an outpatient setting. Ventricular arrhythmias and radiation-related adverse events were monitored at follow-up to determine STAR efficacy and safety. RESULTS: Five patients (100% men; mean age 63 ± 12 years; 80% with ischemic cardiomyopathy; left ventricular ejection fraction 34% ± 15%) underwent STAR. Radioablation was delivered in 82 ± 11 minutes without acute complications. During a mean follow-up of 12 ± 2 months, all patients experienced clinically significant mid- to late-term ventricular arrhythmia recurrence; 2 patients died of complications associated with their advanced heart failure. There were no clinical or imaging evidence of radiation-induced complications in the organs at risk surrounding the scar targeted by radioablation. CONCLUSION: Despite good initial results, STAR did not result in effective arrhythmia control in the long term in a selected high-risk population of patients with scar-related VT. The safety profile was confirmed to be favorable, with no radiation-related complications observed during follow-up. Further studies are needed to explain these disappointing results.

Noninvasive stereotactic radioablation for the treatment of atrial fibrillation: First-in-man experience.

PURPOSE: Catheter ablation is an effective therapy for atrial fibrillation (AF). However, risks remain, and improved efficacy is desired. Stereotactic body radiotherapy (SBRT) is a well-established therapy used to noninvasively treat malignancies and functional disorders with precision. We evaluated the feasibility of stereotactic radioablation for treating paroxysmal AF. METHODS: Two patients with drug-refractory paroxysmal AF underwent pulmonary vein isolation with SBRT. After placement of a percutaneous active fixation temporary pacing lead tracking fiducial, computed tomography (CT) angiography was performed to define left atrial anatomy. A tailored planning treatment volume was created to deliver contiguous linear ablations to isolate the pulmonary veins and posterior wall. Patients were treated on an outpatient basis in the radioablation suite. Clinical follow-up was performed through at least 24 months after therapy. RESULTS: Both patients successfully underwent SBRT planning and treatment without significant early or long-term side effects up to 48 months of follow-up. One patient had AF recurrence after 6 months free of arrhythmia, while the second patient remains free of AF after 24 months with fibrosis detected on MRI scan consistent with the ablation lesion set. An incidentally noted small pericardial effusion occurred in one patient. CONCLUSION: Stereotactic radioablation may be feasible for the treatment of drug-refractory AF. Further evaluation is warranted.

Safety and efficacy of zero fluoroscopy transseptal puncture with different approaches.

INTRODUCTION: Atrial fibrillation (AF) ablation requires access to the left atrium (LA) via transseptal puncture (TP). TP is traditionally performed with fluoroscopic guidance. Use of intracardiac echocardiography (ICE) and three-dimensional mapping allows for zero fluoroscopy TP. OBJECTIVE: To demonstrate safety and efficacy of zero fluoroscopy TP using multiple procedural approaches. METHODS: Patients undergoing AF ablation between January 2015 and November 2017 at five institutions were included. ICE and three-dimensional mapping were used for sheath positioning and TP. Variable technical approaches were used across centers including placement of J wire in the superior vena cava with ICE guidance followed by dragging down the transseptal sheath into the interatrial septum, or guiding the transseptal sheath directly to the interatrial septum by localizing the ablation catheter with three-dimensional mapping and replacing it with the transseptal needle once in position. In patients with pacemaker/implantable cardiac defibrillator leads, pre-/poststudy device interrogation was performed. RESULTS: A total of 747 TPs were performed (646 patients, age 63.1 ± 13.1, 67.5% male, LA volume index 34.5 ± 15.8 mL/m2 , ejection fraction 57.7 ± 10.9%) with 100% success. No punctures required fluoroscopy. Two pericardial effusions, two pericardial tamponades requiring pericardiocentesis, and one transient ischemic attack were observed during the overall ablation procedure, with a total complication rate of 0.7%. There were no other periprocedural complications related to TP, including intrathoracic bleeding, stroke, or death both immediately following TP and within 30 days of the procedure. In patients with intracardiac devices, no device-related complications were observed. CONCLUSION: TP can be safely and effectively performed without the need for fluoroscopy.

Low-fluoroscopy atrial fibrillation ablation with contact force and ultrasound technologies: a learning curve.

BACKGROUND: Fluoroscopy exposure during catheter ablation is a health hazard to patients and operators. This study presents the results of implementing a low-fluoroscopy workflow using modern contact force (CF) technologies in paroxysmal atrial fibrillation (PAF) ablation. METHODS: A fluoroscopy reduction workflow was implemented and subsequent catheter ablations for PAF were evaluated. After vascular access with ultrasound guidance, a THERMOCOOL SMARTTOUCH® Catheter (ST) was advanced into the right atrium. The decapolar catheter was placed without fluoroscopy. A double-transseptal puncture was performed under intracardiac echocardiography guidance. ST and mapping catheters were advanced into the left atrium. A left atrial map was created, and pulmonary vein (PV) isolation was confirmed via entrance and exit block before and after the administration of isoproterenol or adenosine. RESULTS: Forty-three patients underwent PAF ablation with fluoroscopy reduction workflow (mean age: 66±9 years; 70% male), performed by five operators. Acute success rate (PV isolation) was 96.5% of PVs. One case of pericardial effusion, not requiring intervention, was the only acute complication. Mean procedure time was 217±42 minutes. Mean fluoroscopy time was 2.3±3.0 minutes, with 97.7% of patients having < 10 minutes and 86.0% having < 5 minutes. A significant downward trend over time was observed, suggesting a rapid learning curve for fluoroscopy reduction. Freedom from any atrial arrhythmias without reablation was 80.0% after a mean follow-up of 12±3 months. CONCLUSION: Low fluoroscopy time is achievable with CF technologies after a short learning curve, without compromising patient safety or effectiveness.