Acute mitral isthmus block during catheter ablation with vein of Marshall ethanol infusion: Angiographic considerations.

BACKGROUND: Achieving bidirectional mitral isthmus block is still challenging. Conventional ablation methods involve radiofrequency applications on the endocardial aspect of the lateral mitral isthmus, and often epicardial applications inside the coronary sinus. AIM: To evaluate the impact of the systematic use of ethanol infusion in the vein of Marshall on the achievement of acute mitral isthmus block of additional epicardial component lesion. METHODS: We evaluated patients referred to two centres for long-standing persistent atrial fibrillation ablation or recurrent peri-mitral flutter. All patients had pulmonary vein isolation and mitral isthmus line using ethanol infusion in the vein of Marshall for the first procedure and additional radiofrequency ablation lesion if necessary. For redo procedures, additional ablations (atrial lines and complex fractionated atrial electrogram ablations, if needed) were also performed. RESULTS: We included 149 patients, and ethanol infusion in the vein of Marshall was not performed in 27 patients (18%). Among 122 patients, 115 had long-standing persistent atrial fibrillation (94.2%) and seven had peri-mitral flutter (5.8%). The mean duration of continuous atrial fibrillation was 53 months before ablation. Acute bidirectional mitral isthmus block was obtained in 115 (94.2%) of the 122 patients who received ethanol infusion in the vein of Marshall (77% when considering the total population). The mean radiofrequency delivery time to obtain mitral isthmus block was 2.6minutes for the endocardial mitral isthmus radiofrequency ablation and 2.6minutes for the epicardial mitral isthmus radiofrequency ablation. Failure to obtain mitral isthmus block was associated with increased mitral isthmus length and left atrial dilation. No major complications related to ethanol infusion in the vein of Marshall were observed. CONCLUSION: Ethanol infusion in the vein of Marshall, when feasible (82%), was a safe approach to obtaining a high success rate (94%) of acute bidirectional endocardial and epicardial mitral isthmus block.

Galectin-3, Inflammation, and the Risk of Atrial High-Rate Episodes in Patients with Dual Chamber Pacemakers.

Atrial high-rate episodes (AHREs) are atrial tachyarrhythmias that are exclusively detected by cardiac implantable electronic devices (CIEDs) with an atrial lead. The objective of this study was to investigate the incidence and predictive factors for AHREs, and to evaluate the ability of inflammation biomarkers to predict the occurrence of AHREs. 102 patients undergoing CIED procedure who received a dual chamber pacemaker were included. CIED interrogation was performed 1 year after the implantation procedure. Patients were divided into groups according to the occurrence of AHREs, which was the primary endpoint of the study. The mean age of the patients was of 73 ± 8.6 years and 48% were male. The incidence of AHREs was 67% at 1 year follow-up. Patients with AHREs were older, had higher left atrial indexed volume (LAVi), higher baseline galectin-3 levels (1007.5 ± 447.3 vs. 790 ± 411.7 pg/mL) and received betablockers more often, along with amiodarone and anticoagulants. Interestingly, the CHADSVASC score did not differ significantly between the two groups. A cut-off value of galectin > 990 pg/mL predicted AHREs with moderate accuracy (AUC of 0.63, 95% CI 0.52 to 0.73, p = 0.04), and this association was confirmed in the univariate regression analysis (OR 1.0012, 95% CI 1.0001 to 1.0023, p = 0.0328). However, based on the multivariate regression analysis, galectin lost its prognostic significance under the effect of LAVi, which remained the only independent predictor of AHREs (OR 1.0883, 95% CI 1.0351 to 1.1441, p = 0.0009). AHREs are common in CIEDs patients. Galectin-3 may bring additional data in the prediction of AHREs.

Particularities of Catheter Ablation in Women with Atrial Fibrillation and Associated Ischemic Heart Disease.

BACKGROUND: Atrial fibrillation is more common in men, but in the presence of ischemic heart disease, this arrhythmia is more frequent in women. However, like in coronary heart disease, women with atrial fibrillation are suboptimally treated. METHODS: To identify particularities of ablation, in women with atrial fibrillation and ischemic heart disease. RESULTS: 29 women and 26 men, with documented ischemic heart disease and atrial fibrillation, who underwent catheter ablation, were admitted in the study. No significant differences were registered regarding the heart rate control treatment. Electrical cardioversion was significantly higher in men, while pharmacological cardioversion was predominantly recommended in women. The ablation was performed later in women, after 2.55 ± 1.84 years versus 1.80 ± 1.05 in men (p = 0.05). The time elapsed until the ablation was performed was statistically correlated with atypical symptomatology and with the number of antiarrhythmics used prior to the ablation. There were no significant differences for the relapse of atrial fibrillation at 3 months. Quality of life at 3 months after ablation was increased in both groups. CONCLUSION: Catheter ablation is performed much later in women, and the causes responsible for this delay would be more atypical symptoms and a greater number of antiarrhythmics tried before the ablation.

Atrial Fibrillation Ablation in a Patient with Cor Triatriatum Sinister and Left Common Pulmonary Vein: Impact of Left Atrium Anatomy on Ablation Approach.

Atrial fibrillation is the most common presentation in adult patients with cor triatriatum sinister. The key to successful and safe catheter ablation in these patients is an accurate exploration and thorough understanding of the left atrial anatomy, both before and during the procedure. Catheter manipulation is highly dependable on left atrial anatomy, including the interatrial septum, insertion of pulmonary veins and cor triatriatum membrane. Anatomical variants such as the left common pulmonary trunk may influence the ablation approach and outcome. We report the case of a 52-year-old patient with cor triatriatum sinister and the left common pulmonary vein variant who underwent successful high-power, short-duration catheter ablation for paroxysmal atrial fibrillation.

Formula to estimate left atrial volume using antero-posterior diameter in patients with catheter ablation of atrial fibrillation.

ABSTRACT: In patients undergoing atrial fibrillation (AF) ablation, an enlarged left atrium (LA) is a predictor of procedural failure as well as AF recurrence on long term. The most used method to assess LA size is echocardiography-measured diameter, but the most accurate remains computed tomography (CT).The aim of our study was to determine whether there is an association between left atrial diameters measured in echocardiography and the left atrial volume determined by CT in patients who underwent AF ablation.The study included 93 patients, of whom 60 (64.5%) were men and 64 (68.8%) had paroxysmal AF, who underwent AF catheter ablation between January 2018 and June 2019. Left atrial diameters in echocardiography were measured from the long axis parasternal view and the LA volume in CT was measured on reconstructed three-dimensional images.The LA in echocardiography had an antero-posterior (AP) diameter of 45.0 ±â€Š6 mm (median 45; Inter Quartile Range [IQR] 41-49, range 25-73 mm), longitudinal diameter of 67.5 ±â€Š9.4 (median 66; IQR 56-88, range 52-100 mm), and transversal diameter of 42 ±â€Š8.9 mm (IQR 30-59, range 23-64.5 mm). The volume in CT was 123 ±â€Š29.4 mL (median 118; IQR 103-160; range 86-194 mL). We found a significant correlation (r = 0.702; P < .05) between the AP diameter and the LA volume. The formula according to which the AP diameter of the LA can predict the volume was: LA volume = AP diam3 + 45 mL.There is a clear association between the left atrial AP diameter measured on echocardiography and the volume measured on CT. The AP diameter might be sufficient to determine the increase in the volume of the atrium and predict cardiovascular outcomes.

Value of Left Atrial Appendage Function Measured by Transesophageal Echocardiography for Prediction of Atrial Fibrillation Recurrence after Radiofrequency Catheter Ablation.

Atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA) remains a challenging issue. This study aims to explore the left atrial appendage function by transesophageal echocardiography (TEE) and assess its value in predicting AF recurrence following RFCA in paroxysmal AF patients. Eighty-one patients with paroxysmal AF that underwent RFCA were recruited. TEE was performed before ablation with the assessment of left atrial appendage emptying flow velocity (LAAeV). AF recurrence occurred in 24 patients (29.6%) within 12 months after RFCA. The left atrium diameter (LAD) and left atrium volume index (LAVI) were both significantly higher in the recurrence group compared to the non-recurrence group, while the LAAeV was significantly lower in the recurrence group. LAD, LAVi and LAAeV were univariately significant risk factors for AF recurrence after ablation. Based on receiver operating curve (ROC), LAAeV < 40.5 cm/s, LAVi > 40.5 mL and LAD > 41 mm were identified as cut-off values for predicting AF recurrence. In multivariate regression analysis LAAeV < 40.5 cm/s (HR 8.194, 95% CI 2.980-22.530, p < 0.001) was identified as the only statistically significant independent predictor of AF recurrence, as the statistical significance threshold was not achieved for LAVI > 40.5 mL and LAD > 41 mm (p = 0.319; p = 0.507, respectively). A low LAAeV was the only important independent predictor of AF recurrence within 1 year after first RFCA.

The role of intracardiac echocardiography in reducing radiation exposure during atrial fibrillation ablation.

AIMS: Intracardiac echocardiography (ICE) is a relatively young technique used during complex electrophysiology proce-dures, such as atrial fibrillation (AF) ablation. The aim of this study was to assess whether the use of ICE modifies the radia-tion exposure at the beginning of the learning curve in AF ablation. MATERIALS AND METHODS: In this retrospective study, 52 patients, in which catheter ablation for paroxysmal or persistent AF was performed, were included. For 26 patients we used ICE guidance together with fluoroscopy, whereas for the remaining 26 patients we used fluoroscopy alone, all supported by electroanatomical mapping. We compared total procedure time and radiation exposure, including fluoroscopy dose and time between the two groups and along the learning curve. RESULTS: Most of the patients included were suffering from paroxysmal AF (40, 76%), pulmonary vein isolation being performed in all patients, without secondary ablation sites. The use of ICE was associated with a lower fluoroscopy dose (11839.60±6100.6 vs. 16260.43±8264.5 mGy, p=0.041) and time (28.00±12.5 vs. 42.93±12.7 minutes, p=0.001), whereas the mean procedure time was similar between the two groups (181.54±50.3 vs 197.31±49.8 minutes, p=0.348). Radiation exposure was lower in the last 9 months compared to the first 9 months of the study (p<0.01), decreasing gradually along the learning curve. CONCLUSIONS: The use of ICE lowers radiation exposure in AF catheter ablation from the beginning of the learning curve, without any difference in terms of acute safety or efficacy. Aware-ness towards closest to zero radiation exposure during electrophysiology procedures should increase in order to achieve better protection for both patient and medical staff.

Atrial high-rate episodes: a comprehensive review.

Cardiac electronic implantable devices (CIEDs) have the ability to monitor, store and interpret complex arrhythmias, which has generated a new arrhythmic entity: atrial high-rate episodes (AHRE). AHRE are atrial tachyarrhythmias, detected only by CIEDs. They are widely considered a precursor to atrial fibrillation (AF) but can also be represented by other kinds of supraventricular arrhythmias such as atrial flutter or atrial tachycardia. CIED-detected AHRE are associated with an increased risk of stroke, but the risk is significantly lower than the stroke risk of clinical AF. Moreover, there seems to be no temporal correlation between AHRE and thromboembolic events. Because of the current gaps in evidence, the appropriate management of this arrythmia can be challenging. In this review we take into account the epidemiology behind AHRE, predictive factors, clinical impact and management of this arrhythmia.

Assessment of subclinical diabetic cardiomyopathy by speckle-tracking imaging.

BACKGROUND: Diastolic dysfunction is traditionally believed to be the first subclinical manifestation of diabetic cardiomyopathy (DCM), leading to systolic dysfunction and then overt heart failure. However, in the last few years, several studies suggested that systolic subclinical dysfunction measured by speckle-tracking echocardiography (STE) may appear ahead of diastolic dysfunction. In this review, the main endpoint is to show whether subclinical myocardial systolic dysfunction appears ahead of diastolic dysfunction and the implication this may have on the evolution and management of DCM. MATERIALS AND METHODS: We performed a search in PubMed for all relevant publications on the assessment of DCM by STE from 1 June 2015 to 1 June 2020. RESULTS AND CONCLUSIONS: The results illustrate that subclinical systolic dysfunction assessed by STE is present in early DCM stages, with or without the association of diastolic dysfunction. This could be a promising perspective for the early management of patients with DCM leading to the prevention of the overt form of disease.

Catheter ablation of a latent accessory pathway under continuous infusion of adenosine: A case report.

RATIONALE: In absence of conduction over the accessory pathway (AP) during the electrophysiological study, mapping and ablation is impossible. Various techniques can be used to activate absent conduction. In this presentation we describe the first case of latent AP ablation performed under continuous infusion of adenosine. PATIENT CONCERNS: A 65-year-old man, presented to emergency department with atrial fibrillation and antegrade conduction through a left lateral AP. He had palpitations and lightheadedness that occurred every 2 to 3 weeks. DIAGNOSIS: The electrophysiological study confirmed a latent left-side AP. INTERVENTIONS: Catheter ablation could not be performed because of absent conduction through AP. Therefore, a continuous infusion of adenosine was used to activate AP. Ablation was performed at the left lateral mitral ring. OUTCOMES: After catheter ablation and a new adenosine bolus there was no conduction through AP. LESSONS: In case of a latent AP when ablation is difficult to perform because of absent conduction at the time of electrophysiological study, adenosine can be used in doses of 1.5 mg/kg over 5 minutes continuous infusion.

The Impact of Pulmonary Vein Anatomy on the Outcomes of Catheter Ablation for Atrial Fibrillation.

Background and Objectives: Prior studies have identified a number of predictors for Atrial fibrillation (AF) ablation success, including comorbidities, the type of AF, and left atrial (LA) size. Ectopic foci in the initiation of paroxysmal AF are frequently found in pulmonary veins. Our aim was to assess how pulmonary vein anatomy influences the recurrence of atrial fibrillation after radiofrequency catheter ablation. Materials and Methods: Eighty patients diagnosed with paroxysmal or persistent AF underwent radiofrequency catheter ablation (RFCA) between November 2016 and December 2017. All of these patients underwent computed tomography before AF ablation. PV anatomy was classified according to the presence of common PVs or accessory PVs. Several clinical and imagistic parameters were recorded. After hospital discharge, all patients were scheduled for check-up in an outpatient clinic at 3, 6, 9, and 12 months after RFCA to detect AF recurrence. Results: A total of 80 consecutive patients, aged 53.8 ± 9.6 years, 54 (67.5%) men and 26 (32.5%) women were enrolled. The majority of patients had paroxysmal AF 53 (66.3%). Regular PV anatomy (2 left PVs, 2 right PVs) was identified in 59 patients (73.7%), a left common trunk (LCT) was detected in 15 patients (18.7%), an accessory right middle pulmonary vein (RMPV) was found in 5 patients (6.25%) and one patient presented both an LCT and an RMPV. The median follow-up duration was 14 (12; 15) months. Sinus rhythm was maintained in 50 (62.5%) patients. Age, gender, antiarrhythmic drugs, and the presence of cardiac comorbidities were not predictive of AF recurrence. The diagnosis of persistent AF before RFCA was more closely associated with an increase in recurrent AF after RFCA than after paroxysmal AF (p = 0.01). Longer procedure times (>265 minutes) were associated with AF recurrence (p = 0.04). Patients with an LA volume index of over 48.5 (mL/m2) were more likely to present AF recurrence (p = 0.006). Multivariate analysis of recurrence risk showed that only the larger LA volume index and variant PV anatomy were independently associated with AF recurrence. Conclusion: The study demonstrated that an increased volume of the left atrium was the most important predictive factor for the risk of AF recurrence after catheter ablation. Variant anatomy of PV was the only other independent predictive factor associated with a higher rate of AF recurrence.

Tachycardia-induced cardiomyopathy in a patient with left-sided accessory pathway and left bundle branch block: A case report.

RATIONALE: Tachycardia-induced cardiomyopathy (TIC) is defined as systolic and/or diastolic dysfunction of the left ventricle resulting from prolonged elevated heart rates, completely reversible upon control of the arrhythmia. Atrioventricular reentrant tachycardia (AVRT) is one of the most frequent causes of TIC. In its incessant form, it is unlikely to be controlled by pharmacological treatment, catheter ablation being the principal therapeutic option. The coexistence of left bundle branch block (LBBB) in patients with AVRT may cause difficulties in the early diagnosis and management of tachycardia because of the wide complex morphology, making it harder to localize the accessory pathway (AP). PATIENT CONCERNS: A 60-year-old woman, presented incessant episodes of palpitations and shortness of breath due to a LBBB tachycardia leading to hemodynamic instability. DIAGNOSIS: The patient had a wide QRS tachycardia, with LBBB morphology and a heart rate of 160/minute. Echocardiography showed global hypokinesia with 25% left ventricular ejection fraction (LVEF). Considering the patient's clinical picture, TIC was suspected. INTERVENTIONS: The electrophysiological study revealed a left lateral accessory pathway. Catheter ablation was successfully performed at the level of the lateral mitral ring. OUTCOMES: One week after the ablation the patient had no signs of heart failure and the LVEF normalized to 55%. During 6-months follow-up the patient presented no more episodes of tachycardia or heart failure and the LVEF remained normal. LESSONS: AVRT is rarely associated with intrinsic LBBB, being a potential cause of TIC. In these patients, it is unlikely to control the arrhythmia pharmacologically, catheter ablation being the best therapeutic option. The variation of QRS complex duration between LBBB pattern in SR and AVRT could be useful for early diagnosis of an ipsilateral AP on surface ECG.

Intracardiac echocardiography for transseptal puncture. A guide for cardiac electrophysiologists.

The key to a successful catheterization of the left heart chambers is the safe transseptal puncture. Intracardiac echocardiography (ICE) is an attractive tool used in cardiac catheterization and electrophysiology labs to provide detailed images thatcan facilitate transseptal puncture. ICE permits a direct visualization of the endocardium and precisely locates the needle and the sheath against the interatrial septum. Two different ICE catheters are available: a phased array and a mechanical transducer, both being currently used in clinical practice. This paper describes the technique used for guiding transseptal puncture with ICE. Due to its advantages, ICE has currently become an important tool used to maximize the safety of the transseptal puncture and increase efficacy of interventional cardiology procedures.

Recommendations for the use of electrophysiological study: Update 2018.

The field of cardiac electrophysiology has greatly developed during the past decades. Consequently, the use of electrophysiological studies (EPSs) in clinical practice has also significantly augmented, with a progressively increasing number of certified electrophysiology centers and specialists. Since Zipes et al published the Guidelines for Clinical Intracardiac Electrophysiology and Catheter Ablation Procedures in 1995, no official document summarizing current EPS indications has been published. The current paper focuses on summarizing all relevant data of the role of EPS in patients with different types of cardiac pathologies and provides up-to-date recommendations on this topic. For this purpose, the PubMed database was screened for relevant articles in English up to December 2018 and ESC and ACC/AHA Clinical Practice Guidelines, and EHRA/HRS/APHRS position statements related to the current topic were analyzed. Current recommendations for the use of EPS in clinical practice are discussed and presented in 17 distinct cardiac pathologies. A short rationale, evidence, and indications are provided for each cardiac disease/group of diseases. In conclusion, because of its capability to establish a diagnosis in patients with a variety of cardiac pathologies, the EPS remains a useful tool in the evaluation of patients with cardiac arrhythmias and conduction disorders and is capable of establishing indications for cardiac device implantation and guide catheter ablation procedures.

Variation of the PR interval for confirming ventricular pre-excitation on a 12-lead ECG.

We present the case of a 14-year-old female patient with recurrent episodes of paroxysmal supraventricular tachycardia (PSVT). Her ECG showed a PR interval of 160 ms in lead II, and a delta wave pattern in leads V2 and V3, with a normal QRS interval of 100 ms. We analyzed the three criteria for confirmation of minimal pre-excitation: (i) absence of a Q wave in V6; (ii) presence of an R wave in V1 and (iii) absence of an R wave in avR. The 3 criteria were not met and failed to establish a diagnosis of ventricular pre-excitation. The electrophysiological study confirmed the presence of a left accessory pathway. A new criterion was analyzed: the variation of the PR interval on the same ECG. A difference of >30 ms was successful to confirm the presence of an accessory pathway before ablation and its absence after catheter ablation.

Intracardiac echocardiography to guide catheter ablation of an accessory pathway in Ebstein's anomaly. A case report.

We present the case of a 17-year-old girl with Ebstein anomaly and repeated episodes of reentrant tachycardia due to a right posterior accessory pathway. Catheter ablation was performed using intracardiac echocardiography. A ViewFlex Xtra probe was inserted and showed an anormal tricuspid valve with elongated anterior leaflet and low insertion of the septal leaflet towards the apex. The anatomical annulus was identified by the course of the right coronary artery. RF application on the posterior annulus stopped the reentrant arrhythmia. After ablation, programmed stimulation showed absence of both antegrade and retrograde conduction through the accessory pathway.

Intracardiac ultrasound to detect aneurysm in arrhythmogenic right ventricular dysplasia/cardiomyopathy.

Arrhythmogenic right ventricular dysplasia/cardiomyopathy is a genetic disorder characterized by fibrofattty replacement of the right ventricular myocardium. In the revised 2010 Task Force Criteria, a major criteria for ARVD/C is the presence of RV aneurysm by 2D echo. Our report demonstrates that intracardiac ultrasound can detect RV aneurysms and also focal absence of trabeculations which brings additional value to the diagnosis of ARVD/C. A 26-year-old male patient suffering from multiple sustained episodes of ventricular tachycardia was implanted with an internal cardiac defibrillator after confirmation of the disease by cardiac magnetic resonance imaging. Intracardiac ultrasound was performed using a 6F, 9 MHz catheter and the iLAB intravascular system (Boston Scientific). Images of right ventricular inflow tract, outflow tract, apex and pulmonary artery were taken and saved on videotape. ICE revealed loss of trabecular structure at the right ventricular outflow tract with an antero-septal aneurysm at this level. Intravascular ultrasound provides useful information on the presence of aneurysms and of tissue characterization.

Direct ICE imaging from inside the left atrial appendage during ablation of persistent atrial fibrillation.

We present the case of a 59-year-old patient with persistent atrial fibrillation, referred for atrial fibrillation ablation. The procedure was performed with the help of NAVX 3D mapping system (Saint Jude Medical) and iLAB Ultra ICE Plus ultrasound imaging catheter (Boston Scientific). The catheter permits cross-sectional images perpendicular to catheter's long axis. From inside left atrial appendage (LAA) looks trabeculated, due to pectinate muscles running parallel to each other. The presence of a thrombus was excluded from the appendage. The contractility of LAA was also assessed using multiple frames recorded on videotape. Our case demonstrates that LAA's morphology and function can be directly assessed by intracardiac ultrasound with the probe inserted inside the appendage.

Ablation of a left-sided accessory pathway with near-zero fluoroscopy in a 9-year-old boy.

Catheter ablation of cardiac arrhythmias in pediatric population is associated with the risk of ionizing radiation on the child. Due to a greater radiation sensitivity in children and a longer life expectancy newer techniques try to reduce the radiation exposure. A new technique for zero-fluoroscopy catheter ablation is described in a 9-year-old boy who had a left-sided concealed accessory pathway. The NAVX Ensite 3D mapping system permits catheter placement inside the venous system and movement inside the heart chambers without the use of X-rays. The success rate is similar to the techniques requiring X-rays.

Intravascular pulmonary venous ultrasound imaging for catheter ablation of atrial fibrillation.

INTRODUCTION: Atrial fibrillation is the most common cardiac arrhythmia. The development of electroanatomical mapping is an increase demand for advanced intracardiac imaging techniques of the left atrium and pulmonary veins. IVUS can demonstrate quantitative changes like lumen and wall thickness as well as qualitative changes of the pulmonary wall. IVUS could also provide relevant real time imaging of the atrial and pulmonary venous wall during catheter ablation. Areas covered: The Medline and Embase databases were searched for preclinical and clinical studies of IVUS in patients with ablation of atrial fibrillation or left atrial arrhythmias. This article reviews the 15 years of preclinical and clinical experience with IVUS evaluating the pulmonary veins. Expert commentary: IVUS has proven to be a valuable imaging technique in the management of atrial fibrillation ablation. The understanding of the relation between morphological changes and functional results of catheter ablation, combined with the safety profile have made it appealing for interventionists.