Surgical treatment of atrial fibrillation in elderly patients undergoing high risk cardiac surgery.

BACKGROUND: Evaluating outcomes of concurrent Cox-Maze procedures in elderly patients undergoing high-risk cardiac surgery. MEHODS: We retrospectively identified patients aged over 70 years with Atrial Fibrillation (AF) from 2011 to 2017 who had two or more other cardiac procedures. They were subdivided into two groups: 1. Cox-Maze IV AF ablation. 2. No-Surgical AF treatment. A propensity match score was used to generate a homogeneous cohort and to eliminate confounding variables. Heart rhythm was assessed from Holter reports or 12-lead ECG. Follow-up data was collected through telephone consultations and medical records. RESULTS: There were 239 patients. Median follow up was 61 months. 70 patients had Cox-Maze IV procedures (29.3%). Demographic, intra- and post-operative outcomes were similar between groups although duration of pre-operative AF was shorter in Cox-Maze group (p = 0.001). There was no significant 30-day mortality difference in propensity matched cohorts (n = 84. P = 0.078). Sinus rhythm at annual and latest follow-up was 84.9% and 80.0% respectively in Maze group - 160 patients (66.9%) were alive at long-term follow-up with good survival outcomes in Cox Maze group. There was a high proportion of patients in NYHA 1 status in Cox-Maze group. No differences observed in freedom from stroke (p = 0.80) or permanent pacemaker (p = 0.33) between the groups. CONCLUSIONS: Surgical ablation is beneficial in elderly patients undergoing high-risk surgery - promoting excellent long-term freedom from AF and symptomatic / prognostic benefits, without added risk. Therefore, surgical risk should not be reason to deny benefits of concomitant AF-ablation. CLINICAL TRIAL REGISTRATION: Not required.

Procedural and Intermediate-term Results of the Electroanatomical-guided Cardioneuroablation for the Treatment of Supra-Hisian Second- or Advanced-degree Atrioventricular Block: the PIRECNA multicentre registry.

AIMS: Prior case series showed promising results for cardioneuroablation in patients with vagally induced atrioventricular blocks (VAVBs). We aimed to examine the acute procedural characteristics and intermediate-term outcomes of electroanatomical-guided cardioneuroablation (EACNA) in patients with VAVB. METHODS AND RESULTS: This international multicentre retrospective registry included data collected from 20 centres. Patients presenting with symptomatic paroxysmal or persistent VAVB were included in the study. All patients underwent EACNA. Procedural success was defined by the acute reversal of atrioventricular blocks (AVBs) and complete abolition of atropine response. The primary outcome was occurrence of syncope and daytime second- or advanced-degree AVB on serial prolonged electrocardiogram monitoring during follow-up. A total of 130 patients underwent EACNA. Acute procedural success was achieved in 96.2% of the cases. During a median follow-up of 300 days (150, 496), the primary outcome occurred in 17/125 (14%) cases with acute procedural success (recurrence of AVB in 9 and new syncope in 8 cases). Operator experience and use of extracardiac vagal stimulation were similar for patients with and without primary outcomes. A history of atrial fibrillation, hypertension, and coronary artery disease was associated with a higher primary outcome occurrence. Only four patients with primary outcome required pacemaker placement during follow-up. CONCLUSION: This is the largest multicentre study demonstrating the feasibility of EACNA with encouraging intermediate-term outcomes in selected patients with VAVB. Studies investigating the effect on burden of daytime symptoms caused by the AVB are required to confirm these findings.

Sex-related differences in left atrial substrate among patients with atrial fibrillation: evidence from high-density voltage mapping.

BACKGROUND: There is sufficient evidence that women with atrial fibrillation (AF) have a greater symptom burden than men with AF and are more likely to experience recurrence after catheter ablation. However, the mechanisms underlying these sex differences are unclear. METHODS: We prospectively enrolled 125 consecutive patients, including 40 non-AF patients and 85 AF patients, who underwent high-density voltage mapping during sinus rhythm and AF patients who underwent first ablation. RESULTS: Overall, 37 (44%) female patients with AF and 24 (60%) female non-AF patients with a mean age of 61.7 ± 11.6 years and 53.6 ± 16.7 years, respectively, were enrolled in this study. The results showed that the atrial voltage of female AF patients was significantly lower than that of male AF patients (1.11 ± 0.58 mV vs. 1.53 ± 0.65 mV; P = 0.003), while there were no significant sex differences in non-AF patients (3.02 ± 0.86 mV vs. 3.21 ± 0.84 mV; P = 0.498). Multiple linear regression analysis revealed that female sex (- 0.29, 95% confidence interval [CI] - 0.64 to - 0.13, P = 0.004) and AF type (- 0.32, 95% CI - 0.69 to - 0.13, P = 0.004) were the only factors independently associated with voltage. Compared with men, women in the paroxysmal AF group had a 3.5-fold greater incidence of recurrence (adjusted hazard ratio 4.49; 95% CI 1.101-18.332, P = 0.036). Both globally and regionally, the results showed that sex-related differences in voltage values occurred prominently in paroxysmal AF patients but not in nonparoxysmal AF patients. CONCLUSION: Sex-related differences in atrial substrates and arrhythmia-free survival were found in paroxysmal AF patients, suggesting the existence of sex-related pathophysiological factors.

Left atrial strain parameters to predicting elevated left atrial pressure in patients with atrial fibrillation.

OBJECTIVES: To assess the ability of left atrial (LA) strain parameters to discriminate patients with elevated left atrial pressure (LAP) from patients with atrial fibrillation (AF). METHODS AND RESULTS: A total of 142 patients with non-valvular AF who underwent first catheter ablation (CA) between November 2022 and November 2023 were enrolled in the study. Conventional and speckle-tracking echocardiography (STE) were performed in all patients within 24 h before CA, and LAP was invasively measured during the ablation procedure. According to mean LAP, the study population was classified into two groups of normal LAP (LAP < 15 mmHg, n = 101) and elevated LAP (LAP ≥ 15 mmHg, n = 41). Compared with the normal LAP group, elevated LAP group showed significantly reduced LA reservoir strain (LASr) [9.14 (7.97-11.80) vs. 20 (13.59-26.96), p < .001], and increased LA filling index [9.60 (7.15-12.20) vs. 3.72 (2.17-5.82), p < .001], LA stiffness index [1.13 (.82-1.46) vs. .47 (.30-.70), p < .001]. LASr, LA filling index and LA stiffness index were independent predictors of elevated LAP after adjusted by the type of AF, EDT, E/e', mitral E, and peak acceleration rate of mitral E velocity. The receiver-operating characteristic curve (ROC) analysis showed LA strain parameters (area under curve [AUC] .794-.819) could provide similar or greater diagnostic accuracy for elevated LAP, as compared to conventional echocardiographic parameters. Furthermore, the novel algorithms built by LASr, LA stiffness index, LA filling index, and left atrial emptying fraction (LAEF), was used to discriminate elevated LAP in AF with good accuracy (AUC .880, accuracy of 81.69%, sensitivity of 80.49%, and specificity of 82.18%), and much better than 2016 ASE/EACVI algorithms in AF. CONCLUSION: In patients with AF, LA strain parameters could be useful to predict elevated LAP and non-inferior to conventional echocardiographic parameters. Besides, the novel algorithm built by LA strain parameters combined with conventional parameters would improve the diagnostic efficiency.

Salt-losing nephropathy associated with supraventricular arrhythmia.

We present a case of a young man with a new-onset supraventricular arrhythmia accompanied by polyuria and natriuresis with subsequent renal salt-wasting causing hypovolemic hyponatremia. Resolution of the electrolyte imbalance occurred only after successful atrial flutter ablation.

A novel approach to terminate roof-dependent atrial flutter with epicardial conduction through septopulmonary bundle.

Atrial flutter, a prevalent cardiac arrhythmia, is primarily characterized by reentrant circuits in the right atrium. However, atypical forms of atrial flutter present distinct challenges in terms of diagnosis and treatment. In this study, we examine three noteworthy clinical cases of atypical atrial flutter, which offer compelling evidence indicating the implication of the lesser-known Septopulmonary Bundle (SPB). This inference is based on the identification of distinct electrocardiographic patterns observed in these patients and their favorable response to catheter ablation, which is a standard treatment for atrial flutter. Remarkably, in each case, targeted ablation at the anterior portion of the left atrial roof effectively terminated the arrhythmia, thus providing further support for the hypothesis of SPB involvement. These insightful observations shed light on the potential significance of the SPB in the etiology of atypical atrial flutter and introduce a promising therapeutic target. We anticipate that this paper will stimulate further exploration into the role of the SPB in atrial flutter and pave the way for the development of targeted ablation strategies.

Benefits from catheter ablation in patients with pulmonary hypertension: Recent advances.

Supraventricular tachycardia (SVT) is a frequent complication of pulmonary hypertension (PH). The most prevalent SVTs are atrial fibrillation (AF) and typical atrial flutter (AFL), followed by focal and macroreentrant atrial tachycardia (AT) and nodal arrhythmia (AV nodal reentry tachycardia or AV reentry tachycardia). SVT is frequently associated with functional deterioration and right ventricular failure in PH patients. According to some data, reestablishing sinus rhythm is associated with clinical improvement. Catheter ablation of typical AFL, nodal tachyarrhythmias, or other less complex focal ATs have been shown to be feasible, acutely effective, and safe in patients with PH. However, the long-term clinical outcome is modified by the recurrence of index arrhythmia and the onset of a new SVT. Due to right atrial dilatation, technical issues can arise when ablation is carried out. The role of catheter ablation in patients with AF or more complex AT is even less effective. The results mirror the success rate in the general AF population with non-paroxysmal AF. However, the data is limited, and electrophysiological procedures are also more often complicated by specific adverse events in a severely frail population. Despite these limitations, catheter ablation is the treatment of choice in less complex SVT, but the indications for AF ablation must be more individualized.

Left atrial remodeling and voltage-guided ablation outcome in persistent atrial fibrillation patients according to CHA2DS2-VASc score.

BACKGROUND: CHA2DS2-VASc score-related differences have been reported in atrial fibrotic remodeling and prognosis of atrial fibrillation (AF) patients after ablation. There are currently no data on the efficacy of low voltage zone (LVZ)-guided ablation in persistent AF patients according to CHA2DS2-VASc score. We assessed in a cohort of persistent AF patients the extent of LVZ, the regional distribution of LA voltage and the outcome of LA voltage-guided substrate ablation in addition to PVI according to CHA2DS2-VASc score. METHODS: 138 consecutive persistent AF patients undergoing a first voltage-guided catheter ablation were enrolled. 58 patients with CHAD2DS2-VASc score ≥ 3 and 80 patients with CHAD2DS2-VASc score ≤ 2 were included. LA voltage maps were obtained using 3D-electroanatomical mapping system in sinus rhythm. LVZ was defined as < 0.5 mV. RESULTS: In the high CHAD2DS2-VASc score group, LA voltage was lower (1.5 [1.1-2.5] vs. 2.3 [1.5-2.8] mV, p = 0.02) and LVZs were more frequently identified (40% vs. 18%), p < 0.01). Female with CHA2DS2-VASc score ≥ 3 (p = 0.031), LA indexed volume (p = 0.009) and P-wave duration ≥ 150 ms (p = 0.001) were predictors of LVZ. After a 36-month follow-up, atrial arrhythmia-free survival was similar between the two groups (logrank test, P = 0.676). CONCLUSIONS: AF patients with CHAD2DS2-VASc score ≥ 3 display more LA substrate remodeling with lower voltage and more LVZs compared with those with CHAD2DS2-VASc score ≤ 2. Despite this atrial remodeling, they had similar and favorable 36 months results after one single procedure. Unlike male with CHAD2DS2-VASc score ≥ 3, female with CHAD2DS2-VASc score ≥ 3 was predictor of LVZ occurrence.

Comparison of cardiac function and structure after left atrial appendage occlusion without versus with ablation in patients with non-valvular atrial fibrillation: a retrospective study.

The Aim of this study was to investigate the long-term impact of left atrial appendage occlusion (LAAO) on cardiac function and structure in patients with non-valvular atrial fibrillation (NVAF). 157 patients with NVAF who underwent LAAO or combined with ablation were included and divided into simple LAAO group or combined group. Long term impact of LAAO on cardiac function and structure were evaluated. Results showed that the procedures were performed successfully with 6.4% complications. During follow-up, there was a significant decrease of left atrial anteroposterior diameter (LAAD) at 6 months and a significant increase of left ventricular end-diastolic dimension (LVEDD) at 12 months after LAAO. A significant decrease in plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) was noted at 3 months, 6 months and 12 months after procedure. There was a significant decrease of LAAD, LVEDD, left ventricular end-systolic dimension (LVESD) and NT-proBNP levels in combined group at 3 months, 6 months and 12 months post- procedure, while an increase of left ventricular ejection fraction (LVEF). Meanwhile, no significant change of LAAD, LVEDD, LVESD, NT-proBNP and LVEF was seen in simple LAAO group at 3 months follow-up, but a decrease of NT-proBNP during 6 months and 12 months follow-up. Compared with simple LAAO group, combined group was associated with a significant increase of residual flow. In conclusion, LAAO has no significant effect on cardiac structure and function but can significantly reduce NT-proBNP. The improvement of cardiac structure and function in combined therapy comes from the result of ablation, not LAAO.

Ablation apprentices and their first experience of pulmonary vein isolation procedure on paroxysmal atrial fibrillation with different sheaths.

OBJECTIVES: This study aimed at exploring how using different kinds of sheaths will affect the very first ablation procedure of apprentices. METHODS: 15 patients with paroxysmal atrial fibrillation were randomized to used fixed-curve, conventional steerable or visualized steerable sheath, and received complete isolation of pulmonary veins. All ablations were the very first procedure performed by 15 ablation apprentices. The use of fluoroscopy and catheter stability during the PVI were analyzed. RESULTS: Procedure duration was much longer in the fixed-curve group (116.8 ± 27 vs. 62.2 ± 17 vs. 60.4 ± 17, p < 0.001). X-ray exposure was lowest with visualized sheath (17.6 ± 5 vs. 18.6 ± 6 vs. 5.2 ± 6, p < 0.001). CF SD differed significantly, especially at the anterior aspect of LSPV (7.90 ± 2.90 vs. 5.04 ± 2.18 vs. 4.52 ± 2.40, p < 0.001) and posterior aspect of RSPV (6.84 ± 2.79 vs. 3.42 ± 2.04 vs. 3.50 ± 2.30, p < 0.001) in the fixed-curve group. Impedance drop was significantly smaller in the fixed-curve group at the anterior aspect of LSPV (8.74 ± 3.02 vs. 11.49 ± 5.48 vs. 12.57 ± 5.96, p = 0.005). CONCLUSION: Even for the very first ablation procedure of an ablation apprentice, the use of steerable sheaths will significantly reduce the procedure duration and improve the catheter stability, but only visualized steerable sheath can reduce fluoroscopic time.

[Cluster Analysis and Ablation Success Rate in Atrial Fibrillation Patients Undergoing Catheter Ablation]. / æˆ¿é¢¤å°„é¢‘æ¶ˆèžæ‚£è€ çš„èšç±»åˆ†æžåŠæ¶ˆèžæˆåŠŸçŽ‡è¯„ä»·.

Objective: Atrial fibrillation (AF) is a disease of high heterogeneity, and the association between AF phenotypes and the outcome of different catheter ablation strategies remains unclear. Conventional classification of AF (e.g. according to duration, atrial size, and thromboembolism risk) fails to provide reference for the optimal stratification of the prognostic risks or to guide individualized treatment plan. In recent years, research on machine learning has found that cluster analysis, an unsupervised data-driven approach, can uncover the intrinsic structure of data and identify clusters of patients with pathophysiological similarity. It has been demonstrated that cluster analysis helps improve the characterization of AF phenotypes and provide valuable prognostic information. In our cohort of AF inpatients undergoing radiofrequency catheter ablation, we used unsupervised cluster analysis to identify patient subgroups, to compare them with previous studies, and to evaluate their association with different suitable ablation patterns and outcomes. Methods: The participants were AF patients undergoing radiofrequency catheter ablation at West China Hospital between October 2015 and December 2017. All participants were aged 18 years or older. They underwent radiofrequency catheter ablation during their hospitalization. They completed the follow-up process under explicit informed consent. Patients with AF of a reversible cause, severe mitral stenosis or prosthetic heart valve, congenital heart disease, new-onset acute coronary syndrome within three months prior to the surgery, or a life expectancy less than 12 months were excluded according to the exclusion criteria. The cohort consisted of 1102 participants with paroxysmal or persistent/long-standing persistent AF. Data on 59 variables representing demographics, AF type, comorbidities, therapeutic history, vital signs, electrocardiographic and echocardiographic findings, and laboratory findings were collected. Overall, data for the variables were rarely missing (<5%), and multiple imputation was used for correction of missing data. Follow-up surveys were conducted through outpatient clinic visits or by telephone. Patients were scheduled for follow-up with 12-lead resting electrocardiography and 24-hours Holter monitoring at 3 months and 6 months after the ablation procedure. Early ablation success was defined as the absence of documented AF, atrial flutter, or atrial tachycardia >30 seconds at 6-month follow-up. Hierarchical clustering was performed on the 59 baseline variables. All characteristic variables were standardized to have a mean of zero and a standard deviation of one. Initially, each patient was regarded as a separate cluster, and the distance between these clusters was calculated. Then, the Ward minimum variance method of clustering was used to merge the pair of clusters with the minimum total variance. This process continued until all patients formed one whole cluster. The "NbClust" package in R software, capable of calculating various statistical indices, including pseudo t2 index, cubic clustering criterion, silhouette index etc, was applied to determine the optimal number of clusters. The most frequently chosen number of clusters by these indices was selected. A heatmap was generated to illustrate the clinical features of clusters, while a tree diagram was used to depict the clustering process and the heterogeneity among clusters. Ablation strategies were compared within each cluster regarding ablation efficacy. Results: Five statistically driven clusters were identified: 1) the younger age cluster (n=404), characterized by the lowest prevalence of cardiovascular and cerebrovascular comorbidities but the highest prevalence of obstructive sleep apnea syndrome (14.4%); 2) a cluster of elderly adults with chronic diseases (n=438), the largest cluster, showing relatively higher rates of hypertension, diabetes, stroke, and chronic obstructive pulmonary disease; 3) a cluster with high prevalence of sinus node dysfunction (n=160), with patients showing the highest prevalence of sick sinus syndrome and pacemaker implantation; 4) the heart failure cluster (n=80), with the highest prevalence of heart failure (58.8%) and persistent/long-standing persistent AF (73.7%); 5) prior coronary artery revascularization cluster (n=20), with patients of the most advanced age (median: 69.0 years old) and predominantly male patients, all of whom had prior myocardial infarction and coronary artery revascularization. Patients in cluster 2 achieved higher early ablation success with pulmonary veins isolation alone compared to extensive ablation strategies (79.6% vs. 66.5%; odds ratio [OR]=1.97, 95% confidence interval [CI]: 1.28-3.03). Although extensive ablation strategies had a slightly higher success rate in the heart failure group, the difference was not statistically significant. Conclusions: This study provided a unique classification of AF patients undergoing catheter ablation by cluster analysis. Age, chronic disease, sinus node dysfunction, heart failure and history of coronary artery revascularization contributed to the formation of the five clinically relevant subtypes. These subtypes showed differences in ablation success rates, highlighting the potential of cluster analysis in guiding individualized risk stratification and treatment decisions for AF patients.

Extracorporeal Membrane Oxygenation for Protected Catheter Ablation in A Post-Cardiotomy Patient With Electrical Storm.

ABSTRACT: An electrical storm (ES) refers to multiple occurrences of ventricular arrhythmias within a short time. Catheter ablation is a treatment option for ES but can be challenging in unstable cardiovascular patients. We present the case of a 50-year-old patient with poor left ventricular function who experienced ES after emergency coronary artery bypass grafting (CABG). Despite maximal antiarrhythmic therapy, the patient had recurrent ventricular tachycardia and fibrillation (VT/VF), hindering catheter ablation. Elective venoarterial extracorporeal membrane oxygenation (ECMO) support was established, allowing a successful second catheter ablation attempt without complications. The patient was weaned off ECMO the following day and remained in normal sinus rhythm.

Analysis of risk factors for complications in echocardiography-guided percutaneous intramyocardial septal radiofrequency ablation.

BACKGROUND: The feasibility of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) for the treatment of hypertrophic obstructive cardiomyopathy (HOCM) has been previously reported. However, limited investigation has been conducted regarding the complications associated with this procedure. OBJECTIVE: This study aims to analyze the risk factors affecting the occurrence of complications during PIMSRA, such as pericardial effusion, ventricular premature beats, and interventricular septal perforation. In this study, the optimal cut-off values for these risk factors are also explored, and corresponding strategies for prevention are proposed. METHODS: A total of 101 patients diagnosed with HOCM who underwent the PIMSRA procedure from 2021 to 2022 were included in this retrospective analysis. Patients were classified into subgroups with or without complications based on procedural records. Univariate and multivariate regression analyses were conducted to identify independent risk factors for complications during the PIMSRA procedure. RESULTS: There were 48 patients with complications and 53 patients without complications. The heart rate at the start of the procedure and the maximum left ventricular outflow tract gradient (LVOTG) were independent risk factors related to PIMSRA complications. The optimal cut-off values for predicting complication occurrence were a heart rate > 49 bpm at the start of the procedure (OR: 3.79, 95% CI: 1.64-8.78, p = 0.002) and a maximum LVOTG > 92 mmHg (OR: 2.57, 95% CI: 1.15-5.75, p = 0.022), respectively. CONCLUSIONS: The occurrence of PIMSRA complications is primarily associated with the heart rate at the start of the procedure and the maximum LVOTG. It is recommended to establish a comprehensive control plan to minimize the risk of complications during PIMSRA procedures.

RF catheter ablation of AVNRT in a patient with interrupted inferior vena cava anomaly with hemiazygos continuity with persistent left superior vena cava.

Intrahepatic interruption of the inferior vena cava (IVC) with continued hemizygous is a very rare abnormality and sometimes it may be accompanied by other cardiovascular abnormalities. Continuation of the hemizygous vein draining into the right atrium through the left superior vena cava (LSVC) is much rarer. In this paper, we have presented a patient who had simultaneous IVC interrupted with persistent LSVC and suffered from Atrioventricular nodal reentrant tachycardia (AVNRT). Finally, radiofrequencies (RF) catheter ablation for AVNRT was successfully performed through a left subclavian vein access.

Initial experience with zero-fluoroscopy pulmonary vein isolation in patients with atrial fibrillation: single-center observational trial.

Pulmonary vein isolation (PVI) stands as a widely practiced cardiac ablation procedure on a global scale, conventionally guided by fluoroscopy. The concurrent application of electroanatomical mapping systems (EAMS) and intracardiac echocardiography offers a means to curtail radiation exposure. This study aimed to compare procedural outcomes between conventional and our initial zero-fluoroscopy cases in patients with paroxysmal or persistent atrial fibrillation (AF), undergoing point-by-point PVI. Our prospective observational study included 100 consecutive patients with AF who underwent point-by-point radiofrequency PVI. The standard technique was used in the first 50 cases (Standard group), while the fluoroless technique was used in the subsequent 50 patients (Zero group). The zero-fluoroscopy approach exhibited significantly shorter procedural time (59.6 ± 10.7 min vs. 74.6 ± 13.2 min, p < 0.0001), attributed to a reduced access time (17 [16; 20] min vs. 31 [23; 34.5] min, p < 0.001). Comparable results were found for the number of RF applications, total ablation energy, and left atrial dwelling time. In the Zero group, all procedures were achieved without fluoroscopy, resulting in significantly lower fluoroscopy time (0 [0; 0] sec vs. 132 [100; 160] sec, p < 0.0001) and dose (0 [0; 0] mGy vs. 4.8 [4.1; 8.2] mGy, p < 0.0001). The acute success rate was 100%, with no major complications. Zero-fluoroscopy PVI is feasible, safe, and associated with shorter procedure times compared to the standard approach, even in cases without prior experience in zero-fluoroscopy PVI.