Catheter Ablation Of Arrhythmias Research Articles

Endocardial Pulsed Field Ablation and the Oesophagus: Are Atrio-oesophageal Fistulas Now History?

Pulsed field ablation (PFA) is a novel energy form for the catheter ablation of cardiac arrhythmias, which uses electrical fields to mediate myocardial death via irreversible electroporation and other modalities. It is believed to offer relative tissue specificity, lowering - or even eliminating - the risk of complications associated with thermal energy, such as atrio-oesophageal fistulas. The proposed superior safety profile compared to thermal ablation has contributed to the enthusiastic implementation of PFA into clinical practice and is supported by early preclinical and clinical data. However, data about the effects of PFA on the oesophagus remain limited. This organ's susceptibility to PFA has important clinical ramifications and there are two highly relevant questions. First, is the oesophagus absolutely spared by PFA or is there susceptibility to injury at higher field strengths? Second, if oesophageal injury can occur, can atrio-oesophageal fistulas ensue? The aim of this article is to provide a literature review on the effects of PFA on the oesophagus and to address these questions based on the data described.

Anatomical variation of femoral vessels and ultrasound-guided femoral vein puncture for catheter ablation of arrhythmias.

This study aims to investigate the anatomical variations in femoral vasculature and evaluate the clinical value of ultrasound-guided femoral vein puncture in catheter ablation procedures. In this retrospective analysis conducted from January 2023 to March 2023, we examined data from patients who underwent catheter ablation with ultrasound-guided femoral venipuncture. We evaluated the anatomy of the femoral vasculature at both high and low inguinal levels. Based on the relationship between the femoral vein and artery, we classified the anatomy into four types: Type I (vein parallel to artery without overlap), Type II (vein medial to artery with lumen overlap ≤50%), Type III (vein posterior to artery with lumen overlap>50%), and Type IV (vein lateral to artery). Additionally, we assessed procedure-related vascular complications that required interventions or prolonged hospital stays. A total of 254 patients were included in this study. At the upper inguinal level, most cases (92.5%) exhibited Type II, followed by Type I (6.5%), while Type III (0.6%) and IV (0.4%) were less common. At the lower inguinal level, Type II accounted for 70.7%, there was a significantly higher proportion of Type III (23.4%) and Type IV (5.9%). The overall complication rate was 0.4%, no pseudoaneurysm or hematoma was observed in our study. Our study revealed significant anatomical variations in the relationship between the femoral vein and femoral artery. Ultrasound-guided femoral venipuncture significantly reduced vascular complication rate, making it a valuable tool for guiding puncture procedures.

Emerging Tools and Techniques for Catheter Ablation of Cardiac Arrhythmias: A 2024 Update.

Emerging Tools and Techniques for Catheter Ablation of Cardiac Arrhythmias: A 2024 Update.

Major in-hospital complications after catheter ablation of cardiac arrhythmias: individual case analysis of 43 031 procedures.

In-hospital complications of catheter ablation for atrial fibrillation (AF), atrial flutter (AFL), and ventricular tachycardia (VT) may be overestimated by analyses of administrative data. We determined the incidences of in-hospital mortality, major bleeding, and stroke around AF, AFL, and VT ablations in four German tertiary centres between 2005 and 2020. All cases were coded by the G-DRG- and OPS-systems. Uniform code search terms were applied defining both the types of ablations for AF, AFL, and VT and the occurrence of major adverse events including femoral vascular complications, iatrogenic tamponade, stroke, and in-hospital death. Importantly, all complications were individually reviewed based on patient-level source records. Overall, 43 031 ablations were analysed (30 361 AF; 9364 AFL; 3306 VT). The number of ablations/year more than doubled from 2005 (n = 1569) to 2020 (n = 3317) with 3 times and 2.5 times more AF and VT ablations in 2020 (n = 2404 and n = 301, respectively) as compared to 2005 (n = 817 and n = 120, respectively), but a rather stable number of AFL ablations (n = 554 vs. n = 612). Major peri-procedural complications occurred in 594 (1.4%) patients. Complication rates were 1.1% (n = 325) for AF, 1.0% (n = 95) for AFL, and 5.3% (n = 175) for VT. With an increase in complex AF/VT procedures, the overall complication rate significantly increased (0.76% in 2005 vs. 1.81% in 2020; P = 0.004); but remained low over time. Following patient-adjudication, all in-hospital cardiac tamponades (0.7%) and strokes (0.2%) were related to ablation. Major femoral vascular complications requiring surgical intervention occurred in 0.4% of all patients. The in-hospital mortality rate adjudicated to be ablation-related was lower than the coded mortality rate: AF: 0.03% vs. 0.04%; AFL: 0.04% vs. 0.14%; VT: 0.42% vs. 1.48%. Major adverse events are low and comparable after catheter ablation for AFL and AF (∼1.0%), whereas they are five times higher for VT ablations. In the presence of an increase in complex ablation procedures, a moderate but significant increase in overall complications from 2005-20 was observed. Individual case analysis demonstrated a lower than coded ablation-related in-hospital mortality. This highlights the importance of individual case adjudication when analysing administrative data.

MT3 Intracardiac Echocardiography Operational Experience of Chinese Interventional Cardiologists in Conducting Radio-Frequency Catheter Ablation for Cardiac Arrhythmias: A Cross-Sectional Survey Study

MT3 Intracardiac Echocardiography Operational Experience of Chinese Interventional Cardiologists in Conducting Radio-Frequency Catheter Ablation for Cardiac Arrhythmias: A Cross-Sectional Survey Study

The implementation of telemedicine in the follow-up after catheter ablation of arrhythmias: do we still need in-office consultations?

The implementation of telemedicine in the follow-up after catheter ablation of arrhythmias: do we still need in-office consultations?

Case series of catheter-based arrhythmia ablation in pregnant women

Abstract Funding Acknowledgements Type of funding sources: None. Background Antiarrhythmic drugs (AADs) should be used with caution in treating arrhythmias during pregnancy because of side effects, but catheter ablation is a rarely used procedure. Aim To investigate the efficacy and safety of catheter ablation in cardiac arrhythmias during pregnancy. Methods A double-center retrospective case series study was performed. We studied a population of patients undergoing catheter ablation for cardiac arrhythmias during pregnancy between April 2014 and September 2021 in two cardiovascular centers in Hungary. Results 14 procedures [14 electrophysiology studies (EPS), 13 ablations] performed on 13 gravid women (age 30.3±5.2 years, primipara n=6) were studied. The mean gestation period was 24.0 (20.0-27.0) weeks at the time of intervention, and the mean duration of arrhythmia was 44.0±53.0 months. Of the pregnant women 38.5% had comorbidities and 15.4% had structural heart disease. During EPS, 12 patients had inducible arrhythmias. Focal atrial tachycardia was confirmed in 3, AVRT via manifest accessory pathway (AP) in 3 (WPW syndrome) AVRT via counceled AP in 1 case. AVNRT was confirmed in 3, sustained ventricular tachycardia in 2 cases (25-25-8.3-25-16.6%). 11 radiofrequency ablations (RFA) (84.6%) and 2 cryoablations (15.4%) were performed. The electroanatomical mapping system was CARTO in 11 cases (84.6%) and NavX-EnSite in 2 cases (15.4%). Intracardiac echocardiography (ICE) was used in 5 cases (38.5%). Transseptal puncture was performed in 2 cases (15.4%) due to left lateral AP. The average procedure time was 76.0±33.0 min. All the procedures (100.0%) were performed without fluoroscopy. No complications occurred during the procedures. In the long term, arrhythmia-free survival was achieved in all cases (100.0%), but in two patients, we used AADs to achieve freedom of arrhythmia. With AADs, the mean birth weight was lower than that of fetuses of gravidas not taking drugs (2110±1314 vs. 3253±458 g). APGAR was within the normal range in all cases [9.0/10.0 (IQR) (9.0-10.0/9.3-10.0)]. Conclusions Zero-fluoroscopic catheter ablation during pregnancy is an effective and safe treatment method when needed. Catheter ablation for persistent maternal arrhythmias has a more beneficial effect on fetal development than the use of AADs. Indeed, long-term outcome and safety need to be investigated in a larger patient population.

MP-453088-7 PROOF-OF-CONCEPT FORWARD-SOLUTION MAPPING OF A FOCAL ATRIAL TACHYCARDIA ORIGIN USING THE OUTPATIENT 12-LEAD ELECTROCARDIOGRAM

Arrhythmia source mapping is essential to the delivery of targeted catheter ablation for cardiac arrhythmias. Whether mapping may be performed using outpatient 12-lead electrocardiogram (ECG) data was unknown. The objective of this proof-of-concept study was to evaluate the feasibility, temporal efficiency, and accuracy for forward-solution mapping using clinical ECG data obtained outside the electrophysiology laboratory. The patient is a 24-year-old female with recurrent, symptomatic focal atrial tachycardia (focal AT) diagnosed by 12-lead ECG in the outpatient clinic. After unsuccessful medical therapy, she elected to proceed with catheter ablation at Kaiser Santa Clara Medical Center. 12-lead ECG data from the clinical ECG database (Muse, GE Medical) was exported and transferred to the forward-solution mapping system (vMap, Vektor Medical). After data upload and system confirmation of acceptable data quality, a selection window was placed around the focal AT P-wave of interest (Figure A). The mapping process was initiated and the probabilistic source locations for the focal AT were displayed by the system. These results were then compared to the results of invasive activation mapping. Results from the forward-solution analysis demonstrated a highest probability focal AT source at the anterior base of the left atrial appendage (Figure B). Total processing time following upload of the ECG data into the clinical system was less than 3 minutes. Invasive activation mapping using the electroanatomic mapping system (Carto, Biosense-Webster) also demonstrated the site of early activation at the anterior base of the left atrial appendage (Figure C). Center-to-center spatial error between the forward-solution result and the site of early activation by invasive mapping was 8.8 mm. Forward-solution arrhythmia source mapping using data from a commercial ECG system obtained outside the electrophysiology laboratory is feasible, time-efficient, and demonstrates excellent agreement with invasive electroanatomic mapping. Future studies are required to determine whether this process may facilitate the delivery of targeted arrhythmia therapy in larger populations.

PO-04-198 IMPROVED SAFETY OF CATHETER ABLATION FOR VENTRICULAR ARRHYTHMIA: A DECADES’ EXPERIENCE

Ventricular arrhythmia (VA) is a major contributor to cardiovascular morbidity and mortality. Catheter ablation is an effective therapeutic intervention for VA and has been increasingly used. Understanding the evolution of procedural risk informs risk-benefit assessment and patient selection. Examine the evolution of the safety of catheter ablation for VA. We examined our institutional experience with VA catheter ablation including premature ventricular contraction (PVC) and ventricular tachycardia (VT) ablation. A total of 2,300 patients had VA ablation over the past decade from January 2009 to October 2022. Thirty-day major complication data were obtained by individual chart review and clinical patient follow-up, and stored in our prospective institutional database. Major complications were defined as intra- or post-procedural complications leading to additional procedures or prolonged hospital stay, or post-discharge complications requiring re-hospitalization. Three time periods (2009-2013, 2014-2018 and 2019-2022) were a priori selected to examine trends in thirty-day complication outcomes. Logistic regression was implemented to test for a trend in the rate of major complications over the three time periods. In our single-center cohort, 887, 896 and 517 patients underwent catheter ablation for VA between 2009-2013, 2014-2018 and 2019-2022, respectively. We found a consistent trend of overall decreased thirty-day major complications across the three pre-defined time periods for ventricular arrhythmia catheter ablation (p=0.006). The trend of decreasing incidence of major complications persisted when we examined PVC and VT ablations separately, however, it did not reach the threshold for statistical significance (Figure 1a). The cumulative incidence of major complications in the most contemporary era was 1.3% for PVC ablation, and 2.3% for VT ablation, respectively. The decrease in major complications was primarily driven by reduction in the rate of pericardial effusion, vascular complications and thromboembolism associated with VA catheter ablation (Figure 1b). Significant strides have been made in improving the safety profile of catheter ablation for VAs. These findings may inform patient selection as the proportion of patients with ventricular arrhythmia referred for catheter ablation increases.

Long-term follow-up in preschool children after radiofrequency catheter ablation of arrhythmias.

Radiofrequency ablation (RFA) is the standard method of treatment for tachyarrhythmias in school children, and it leads to complete recovery in children without structural heart disease. However, RFA in young children is limited by the risk of complications and unstudied remote effects of radiofrequency lesions. To present the experience of RFA of arrhythmias and the results of follow-up of younger children. RFA procedures (n=255) were performed in 209 children with arrhythmias from 0 to 7 years old. The arrhythmias were presented with atrioventricular reentry tachycardia withWolff-Parkinson-White(WPW) syndrome (56%), atrial ectopic tachycardia (21.5%), atrioventricular nodal reentry tachycardia (4.8%), and ventricular arrhythmia (17.2%). The overall effectiveness of RFA, considering the repeated procedures performed due to the primary ineffectiveness and recurrencies, was 94.7%. There was no mortality associated with RFA in patients, including young patients. All cases of "major" complications are associated with RFA of the left-sided accessory pathway and tachycardia foci and are represented by the mitral valve damage in three patients (1.4%). Tachycardia and preexcitation recurred in 44 (21%) patients. There was a correlation between recurrences and parameters of RFA (odds ratio 0.894; 95% confidence interval: 0.804-0.994; p=.039). Reducing the maximum power of effective applications in our study increased the risk of recurrence. The use of the minimum effective parameters of RFA in children reduces the risk of complications, but increases arrhythmia recurrence rate.

Robotic magnetic-guided catheter ablation in patients with congenital heart disease: a systematic review and pooled analysis

ABSTRACT Background Robotic magnetic navigation (RMN) has emerged as a potential solution to overcome challenges associated with catheter ablation of arrhythmias in patients with congenital heart disease (CHD). Objectives To assess safety and efficacy of RMNguided catheter ablation in patients with CHD. Design and Methods A systematic review and pooled analysis was conducted on patients with CHD who underwent RMNguided catheter ablation. Random effects models were used to generate pooled estimates with the inverse variance method used for weighting studies. Results Twentyfour nonoverlapping records included 167 patients with CHD, mean age 36.5 years, 44.6% female. Type of CHD was simple in 27 (16.2%), moderate in 32 (19.2%), and complex in 106 (63.5%). A total of 202 procedures targeted 260 arrhythmias, the most common being macroreentrant atrial circuits. The mean procedural duration was 207.5 minutes, with a mean fluoroscopy time of 12.1 minutes. The pooled acute success rate was 89.2% [95% CI (77.8%, 97.4%)]. Freedom from arrhythmia recurrence was 84.5% [95% CI (72.5%, 94.0%)] over a mean follow-up of 24.3 months. The procedural complication rate was 3.5% with no complication attributable to RMN technology. Conclusion RMN-guided ablation appears to be safe and effective across a variety of arrhythmia substrates and types of CHD.

Long-term results of zero-fluoroscopy catheter ablation in pregnant patients with arrhythmias: a 2-year follow-up study

Abstract Funding Acknowledgements Type of funding sources: None. Background Incidences of rhythm disturbance in pregnant are commonly seen. Catheter ablation of arrhythmias has been shown to be effective and safe. Data on perinatal outcomes and results of zero-fluoroscopy catheter ablation in pregnant patients is limited. Purpose the aim of our study is to observe long-term results and perinatal outcomes in pregnant women with arrhythmias, treated by zero-fluoroscopy catheter ablation method. Methods There were 48 pregnant women, who underwent zero-fluoroscopy catheter ablation (Mean age of pregnant was 25.7±4.3 years, mean gestation age 24.1 ±3.2 weeks). Procedure-related complications, perinatal outcomes and arrhythmia recurrence were documented during 24 months follow-up. Results The most common arrhythmias were atrioventricular nodal reentrant tachycardia (n=21; 43.75%). This was followed by Wolff–Parkinson–White syndrome (n=15; 31.25%). Combination of accessory pathways with slow conduction ways were found in 3 cases (6.25%). In six cases were ablation due to frequent premature ventricular contraction (12.5%). Ventricular tachycardia was rare during pregnancy (n=3; 6.25%). Zero-fluoroscopy catheter ablation was performed under the guidance of CARTO (n=21; 43.75%) and Ensite Precision systems (n=27; 56.25%). The median procedural time was 71±15 minutes. Interventions were effective in all cases (100%). Procedural complication was in one patient (2.1%), who developed an ileofemoral thrombosis. Pregnancy course after ablation procedure was benign in all patients. Perinatal outcomes: spontaneus vaginal delivery was in the majority of cases (n=36; 75%). Twelve pregnancies (25%) were delivered by cesarean section due to obstetric indicators. Intrapartum hemorrhage was 335.2±228.92 ml. Two women had placental abraption and preeclampsia (4.2%). Maternal adverse cardiac events were none declared. There were 48 live births (in all cases). Fetal birth weight was 3324.7±684.4 grams, 5 minute Apgar was 8.4±1.3. There were no maternal and fetal mortality. At 24 months there were no arrhythmia recurrence. Conclusions Zero-fluoroscopy catheter ablation method is safe and effective in pregnant women with arrhythmias. Pregnancy course and outcomes after this procedure is bening in the majority of cases.

Ultrasound-Guided Access Reduces Vascular Complications in Patients Undergoing Catheter Ablation for Cardiac Arrhythmias.

Femoral vascular access using the standard anatomic landmark-guided method is often limited by peripheral artery disease and obesity. We investigated the effect of ultrasound-guided vascular puncture (UGVP) on the rate of vascular complications in patients undergoing catheter ablation for atrial or ventricular arrhythmias. The data of 479 patients (59% male, mean age 68 years ± 11 years) undergoing catheter ablation for left atrial (n = 426; 89%), right atrial (n = 28; 6%) or ventricular arrhythmias (n = 28; 6%) were analyzed. All patients were on uninterrupted oral anticoagulants and heparin was administered intravenously during the procedure. Femoral access complications were compared between patients undergoing UGVP (n = 320; 67%) and patients undergoing a conventional approach (n = 159; 33%). Complication rates were also compared between patients with a BMI of >30 kg/m2 (n = 136) and patients with a BMI < 30 kg/m2 (n = 343). Total vascular access complications including mild hematomas were n = 37 (7.7%). In the conventional group n = 17 (10.7%) and in the ultrasound (US) group n = 20 (6.3%) total vascular access complications occurred (OR 0.557, 95% CI 0.283-1.096). UGVP significantly reduced the risk of hematoma > 5 cm (OR 0.382, 95% CI 0.148, 0.988) or pseudoaneurysm (OR 0.160, 95% CI 0.032, 0.804). There was no significant difference between the groups regarding retroperitoneal hematomas or AV fistulas (p > 0.05). In patients with BMI > 30 kg/m2, UGVP led to a highly relevant reduction in the risk of total vascular access complications (OR 0.138, 95% CI 0.027, 0.659), hematomas > 5 cm (OR 0.051, 95% CI 0.000, 0.466) and pseudoaneurysms (OR 0.051, 95% CI 0.000, 0.466). UGVP significantly reduces vascular access complications. Patients with a BMI > 30 kg/m2 seem to particularly profit from a UGVP approach.

Feasibility of wideband dielectric imaging to guide temperature-controlled atrial fibrillation ablation.

The DiamondTemp (DT) radiofrequency (RF) ablation catheter (Medtronic, Dublin, Ireland) has been introduced for atrial fibrillation (AF) ablation. It features 6 thermocouples at its tip, imbedded in a synthetic diamond material that offers high thermal diffusivity. The technology allows temperature-controlled ablation combining high ablation power levels with a direct temperature feedback consequently resulting in homogeneous atrial lesion formation.1 Recently, a novel wideband dielectric imaging system (KODEX-EPD, EPD Solutions, Philips, Amsterdam, The Netherlands) was introduced to guide catheter ablation of cardiac arrhythmias.

Catheter ablation of sustained idiopathic right ventricular outflow tract tachycardia in a pregnant patient without fluoroscopy

In 2020, our department has performed 739 operations on nonpregnant patients. Additionally, 545 highly successful nonfluoroscopic catheter ablation of cardiac arrhythmias were routinely performed using a three-dimensional navigation system, including 47 patients with idiopathic ventricular tachycardia (VT) from the right ventricular outflow tract (RVOT).
 A 38-year-old female patient with a structurally normal heart was admitted to our hospital in 1011 weeks of her third pregnancy because she sustained recurrent 166 regular heartbeats per minute, wide QRS-complex tachycardia with left bundle branch morphology, and frequent premature ventricular contractions on Holter monitoring with complaints of presyncope and dyspnea. Standard antiarrhythmic drugs failed to control tachycardia. This case report presents our initial successful experience of the rescue zero-fluoroscopy catheter ablation of sustained poorly tolerated idiopathic RVOT tachycardia in a pregnant patient. Our result suggests that this technique may be considered in the few rare cases in which drug-resistant, sustained frequent VT is accompanied by hemodynamic compromise with fluoroscopy contraindication.
 AIM: Diagnostic algorithm of idiopathic sustained drug-resistant, poorly tolerated VT and the possibility of radiofrequency catheter ablation in the most vulnerable first trimester of pregnancy without fluoroscopy were presented in our case report.

Zero-fluoroscopy catheter ablation in pregnant women: outcomes and prognosis

Abstract Funding Acknowledgements Type of funding sources: None. Background Arrhythmias are common in pregnant. Catheter ablation is effective treatment in cases of drug refractory arrhythmias. However, data are scarce on outcomes and prognosis of catheter ablation in this population of patient. Purpose To define the cohort of pregnant undergoing for catheter ablation for arrhythmias, characterize obstetric and neonatal outcomes and prognosis. Methods This single-center, prospective study included all catheter ablation procedures for arrhythmias performed in pregnant from January 2015 until December 2019. Primary outcome was recurrence of arrhythmia. Baseline clinical characteristics, complication rates, obstetric and neonatal outcomes were also evaluated. Results In total, we included 48 patients (aged 27.04±4.32 years, mean gestation age 21.8±4.22 weeks), indicated for catheter ablation due to drug refractory arrhythmias. The most common arrhythmia was atrioventricular nodal reentrant tachycardia (n=20; 41.7%). Ablation of accessory pathways performed in 16 cases (33.3%): in left free wall (n=8), in right free wall (n=7), posteroseptal (n=1). In 3 cases was observed combination of accessory pathways with slow conduction ways. Ablation of the right ventricular outflow tract was performed in 9 cases (18.7%) of ventricular tachycardia. In all cases catheter ablation was performed successfully without fluoroscopy. One patient developed an ileofemoral thrombosis. No other complication after ablation was noted. Pregnancy course was benign in all cases without termination. Premature birth was in 2 cases at 35 and 36 weeks of gestation. Full-term pregnancy was in the majority. Preeclampsia developed in 2 pregnant women. In 75% of pregnancy was vaginal delivery, in 25% - Cesarean section. Fetal birth weight was 3226.34±623,1 grams, 5 minute Apgar was 8,92±1,8. There were 48 live births without maternal and fetal mortality. During 1 year follow-up there was no arrhythmia recurrence. Conclusions Non-fluoroscopic catheter ablation of arrhythmias in pregnant women is effective treatment options, with a high success rate, low rates of complication, favorable outcomes and prognosis.

Near zero vascular complications using echo-guided puncture during catheter ablation of arrhythmias: A retrospective study and literature review.

BackgroundCatheter ablation (CA) is routinely used for the treatment of arrhythmias. Vascular complications are the most common complications during these procedures. Previous data reported that ultrasound (US)‐guided puncture is a useful method to avoid vascular complications. We reported our experience using US‐guided puncture in patients undergoing CA for arrhythmias.MethodsA total of 273 patients (mean age 57 ± 17 years; 58% male) were referred to our center for CA of arrhythmias from January 2016 to December 2019. All procedures were performed by expert operators, and US‐guided vascular access was performed on all patients. Doppler sonography was performed the day after the procedure on all patients.ResultsEighty‐four patients (31%) underwent atrioventricular nodal reentrant tachycardia ablation, 49 patients (18%) atrioventricular reentrant tachycardia ablation, 14 patients (5%) atrial tachycardia ablation, 25 patients (9%) atrial flutter ablation, 63 patients (23%) atrial fibrillation ablation, and 38 patients (14%) ventricular tachycardia ablation. Vascular pseudo‐aneurysms and arteriovenous fistula were defined as major complications; furthermore, venous thrombosis and inguinal hematomas were as defined minor complications. The percentage of major vascular complications was 0.3% (1 arteriovenous fistula) and the percentage of minor vascular complications was 0.3% (1 venous thrombosis).DiscussionUltrasound‐guided vascular puncture in patients undergoing CA is useful to improve procedural success and reduce complications.

Brain-based measures of nociception during general anesthesia with remifentanil: A randomized controlled trial.

BackgroundCatheter radiofrequency (RF) ablation for cardiac arrhythmias is a painful procedure. Prior work using functional near-infrared spectroscopy (fNIRS) in patients under general anesthesia has indicated that ablation results in activity in pain-related cortical regions, presumably due to inadequate blockade of afferent nociceptors originating within the cardiac system. Having an objective brain-based measure for nociception and analgesia may in the future allow for enhanced analgesic control during surgical procedures. Hence, the primary aim of this study is to demonstrate that the administration of remifentanil, an opioid widely used during surgery, can attenuate the fNIRS cortical responses to cardiac ablation.Methods and findingsWe investigated the effects of continuous remifentanil on cortical hemodynamics during cardiac ablation under anesthesia. In a randomized, double-blinded, placebo (PL)-controlled trial, we examined 32 pediatric patients (mean age of 15.8 years,16 females) undergoing catheter ablation for cardiac arrhythmias at the Cardiology Department of Boston Children’s Hospital from October 2016 to March 2020; 9 received 0.9% NaCl, 12 received low-dose (LD) remifentanil (0.25 mcg/kg/min), and 11 received high-dose (HD) remifentanil (0.5 mcg/kg/min). The hemodynamic changes of primary somatosensory and prefrontal cortices were recorded during surgery using a continuous wave fNIRS system. The primary outcome measures were the changes in oxyhemoglobin concentration (NadirHbO, i.e., lowest oxyhemoglobin concentration and PeakHbO, i.e., peak change and area under the curve) of medial frontopolar cortex (mFPC), lateral prefrontal cortex (lPFC) and primary somatosensory cortex (S1) to ablation in PL versus remifentanil groups. Secondary measures included the fNIRS response to an auditory control condition. The data analysis was performed on an intention-to-treat (ITT) basis. Remifentanil group (dosage subgroups combined) was compared with PL, and a post hoc analysis was performed to identify dose effects. There were no adverse events. The groups were comparable in age, sex, and number of ablations. Results comparing remifentanil versus PL show that PL group exhibit greater NadirHbO in inferior mFPC (mean difference (MD) = 1.229, 95% confidence interval [CI] = 0.334, 2.124, p < 0.001) and superior mFPC (MD = 1.206, 95% CI = 0.303, 2.109, p = 0.001) and greater PeakHbO in inferior mFPC (MD = −1.138, 95% CI = −2.062, −0.214, p = 0.002) and superior mFPC (MD = −0.999, 95% CI = −1.961, −0.036, p = 0.008) in response to ablation. S1 activation from ablation was greatest in PL, then LD, and HD groups, but failed to reach significance, whereas lPFC activation to ablation was similar in all groups. Ablation versus auditory stimuli resulted in higher PeakHbO in inferior mFPC (MD = 0.053, 95% CI = 0.004, 0.101, p = 0.004) and superior mFPC (MD = 0.052, 95% CI = 0.013, 0.091, p < 0.001) and higher NadirHbO in posterior superior S1 (Pos. SS1; MD = −0.342, 95% CI = −0.680, −0.004, p = 0.007) during ablation of all patients. Remifentanil group had smaller NadirHbO in inferior mFPC (MD = 0.098, 95% CI = 0.009, 0.130, p = 0.003) and superior mFPC (MD = 0.096, 95% CI = 0.008, 0.116, p = 0.003) and smaller PeakHbO in superior mFPC (MD = −0.092, 95% CI = −0.680, −0.004, p = 0.007) during both the stimuli. Study limitations were small sample size, motion from surgery, indirect measure of nociception, and shallow penetration depth of fNIRS only allowing access to superficial cortical layers.ConclusionsWe observed cortical activity related to nociception during cardiac ablation under general anesthesia with remifentanil. It highlights the potential of fNIRS to provide an objective pain measure in unconscious patients, where cortical-based measures may be more accurate than current evaluation methods. Future research may expand on this application to produce a real-time indication of pain that will aid clinicians in providing immediate and adequate pain treatment.Trial registrationClinicalTrials.gov NCT02703090

Catheter ablation for atrial fibrillation: impact on mortality, morbidity, quality of life, and implications for the future.

Despite the advances in technologies and techniques in the field of catheter ablation for cardiac arrhythmias, it is estimated that the prevalence of atrial fibrillation (AF) will further increase in the nearest future. The latest trials have proven the beneficial effect on mortality after pulmonary vein isolation in patients with impaired left ventricular function, while no such effect has been seen in patients without left ventricular dysfunction. This raises the question of whether catheter ablation for AF is still suited for the latter patient cohort or whether the endpoint of mortality is not adequate enough. Not only does pulmonary vein isolation reduce the burden of atrial fibrillation, but it also somehow alters the patients’ perception of it in the case of recurrence. Independent of the presence of ventricular dysfunction, patients experience a relief of AF-related symptoms, which is accompanied by an increase in quality of life based on the available patient-reported outcome measures, despite AF recurrence. Trials that are currently recruiting patients seek to unveil the accountable circumstances for these remaining uncertainties and help expand our understanding of a procedure that has been routinely performed for two decades.

Impact of obesity on acute complications of catheter ablation for cardiac arrhythmia.

The prevalence of obesity is increasing. However, data on the periprocedural complication rate of catheter ablation for arrhythmia in patients stratified by body mass index (BMI) arescarce. This study included 1000 consecutive patients (age 62.0 ± 14.4 years) undergoing catheter ablation for cardiac arrhythmia. The primary study endpoint was any periprocedural major complication (cardiac tamponade, pseudoaneurysm, arteriovenous fistula, transient ischemic attack, stroke, valve damage, myocardial infarction, or death). The mean BMI was 27.6 ± 5.1 kg/m2 and the majority of patients were overweight (BMI 25.0-29.9 kg/m2 , 43.4%). A BMI of 30.0-34.9 kg/m2 (Class I obesity) was present in 177 (17.7%) of patients, a BMI of 35.0-39.9 kg/m2 (Class II obesity) in 67 (6.7%), and a BMI ≥ 40 kg/m2 (Class III obesity) in 16 (1.6%). There were 31 major complications (3.1%) and one fatality (0.1%) due to terminal heart failure in a patient undergoing palliative ventricular tachycardiaablation. There was no significant impact of the BMI on the rate of major complications (p = .495). Compared to normal weight patients, odds ratios for complications in overweight patients, as well as Class I, II, and III obesity were 1.1 (95% confidence interval (CI): 0.8, 1.7), 1.3 (CI: 0.6, 2.6), 1.4 (CI: 0.5, 4.1), and 1.6 (CI: 0.4, 6.3), respectively. Radiation exposure and procedure duration were significantly increased in obese patients (p < .001 and p = .001, respectively). In this study, obesity did not have a significant impact on the incidence of periprocedural complications after CA for cardiac arrhythmia.