Transseptal approach for catheter ablation of left-sided accessory pathways in children with Marfan syndrome:A case report

BACKGROUND Left-sided accessory pathways(APs)can be accessed with either a transaortic(TA)or transseptal approach(TS).For children with Marfan syndrome(MFS)who have aortic disease,the use of TA can aggravate the disease,making TS the best choice for these patients.CASE SUMMARY A 10-year-old girl was hospitalized because of intermittent heart palpitations and chest tightness.She was diagnosed with MFS,supraventricular tachycardia,Wolff-Parkinson-White syndrome,and left-sided AP was detected by cardiac electrophysiological.Catheter ablation was successfully performed via TS under the guidance of the Ensite system.During the follow-up,no recurrence or complications occurred.CONCLUSION The TS for catheter ablation of left-sided APs can be considered in children with MFS.Adequate evaluation and selection of the appropriate puncture site are particularly important.

Mechanisms and clinical significance of early recurrences of atrial arrhythmias after catheter ablation for atrial fibrillation

Early recurrence of atrial arrhythmias(ERAA) after ablation is common and strongly predicts late recurrences and ablation failure. However, since arrhythmia may eventually resolve in up to half of patients with ERAA, guidelines do not recommend immediate reintervention for ERAA episodes occurring during a 3-mo postablation blanking period. Certain clinical demographic, electrophysiologic, procedural, and ERAA-related characteristics may predict a higher likelihood of longterm ablation failure. In this review, we aim to discuss potential mechanisms of ERAA, and to summarize the clinical significance, prognostic implications, and treatment options for ERAA.

Catheter ablation for atrial fibrillation is associated with reduced risk of mortality in the elderly:a prospective cohort study and propensity score analysis

Background It is unclear whether catheter ablation(CA)for atrial fibrillation(AF)affects the long-term prognosis in the elderly.This study aims to evaluate the relationship between CA and long-term outcomes in elderly patients with AF.Methods Patients more than 75 years old with non-valvular AF were prospectively enrolled between August 2011 and December 2017 in the Chinese Atrial Fibrillation Registry Study.Participants who underwent CA at baseline were propensity score matched(1:1)with those who did not receive CA.The outcome events included all-cause mortality,cardiovascular mortality,stroke/transient ischemic attack(TIA),and cardiovascular hospitalization.Results Overall,this cohort included 571 ablated patients and 571 non-ablated patients with similar characteristics on 18 dimensions.During a mean follow-up of 39.75±19.98 months(minimum six months),24 patients died in the ablation group,compared with 60 deaths in the non-ablation group[hazard ratio(HR)=0.49,95%confidence interval(CI):0.30-0.79,P=0.0024].Besides,6 ablated and 29 non-ablated subjects died of cardiovascular disease(HR=0.25,95%CI:0.11-0.61,P=0.0022).A total of 27 ablated and 40 non-ablated patients suffered stroke/TIA(HR=0.79,95%CI:0.48-1.28,P=0.3431).In addition,140 ablated and 194 non-ablated participants suffered cardiovascular hospitalization(HR=0.84,95%CI:0.67-1.04,P=0.1084).Subgroup analyses according to gender,type of AF,time since onset of AF,and anticoagulants exposure in initiation did not show significant heterogeneity.Conclusions In elderly patients with AF,CA may be associated with a lower incidence of all-cause and cardiovascular mortality.

Long-term results of single-procedure catheter ablation for atrial fibrillationin pre-and post-menopausal women

Objectives To address whether menopause affects outcome of catheter ablation （CA） for atrial fibrillation （AF） by comparing the safety and long-term outcome of a single-procedure in pre-and post-menopausal women. Methods A total of 743 female patients who underwent a single CA procedure of drug-refractory AF were retrospectively analyzed. The differences in clinical presentation and outcomes of CA for AF between the pre-menopausal women （PreM group, 94 patients, 12.7%） and the post-menopausal women （PostM group, 649 patients, 87.3%） were assessed. Results The patients in the PreM group were younger （P＆lt;0.001） and less likely to have hypertension （P＆lt;0.001） and diabetes （P=0.005） than those in the PostM group. The two groups were similar with regards to the proportion of concomitant mitral valve regurgitation coronary artery disease, left atrium dimensions, and left ventricular ejection fraction. The overall rate of complica-tions related to AF ablation was similar in both groups （P=0.385）. After 43 （16-108） months of follow-up, the success rate of ablation was 54.3%in the PreM group and 54.2%in the PostM group （P=0.842）. The overall freedom from atrial tachyarrhythmia recurrence was simi-lar in both groups. Menopause was not found to be an independent predictive factor of the recurrence of atrial tachyarrhythmia. Conclusions The long-term outcomes of single-procedure CA for AF are similar in pre-and post-menopausal women. Results indicated that CA of AF appears to be as safe and effective in pre-menopausal women as in post-menopausal women.

Catheter ablation of atrial fibrillation facilitated by preprocedural three-dimensional transesophageal echocardiography: Long-term outcome

AIM To evaluate the long-term outcome of catheter ablation of atrial fibrillation(AF) facilitated by preprocedural threedimensional(3-D) transesophageal echocardiography.METHODS In 50 patients, 3D transesophageal echocardiography(3D TEE) was performed immediately prior to an ablation procedure(paroxysmal AF: 30 patients, persistent AF: 20 patients). The images were available throughout the ablation procedure. Two different ablation strategies were used. In most of the patients with paroxysmal AF, the cryoablation technique was used(Arctic Front Balloon, Cryo Cath Technologies/Medtronic; group A2). In the other patients, a circumferential pulmonary vein ablation was performed using the CARTO system [Biosense Webster; group A1(paroxysmal AF), group B(persistent AF)]. Success rates and complication rates were analysed at 4-year follow-up.RESULTS A 3D TEE could be performed successfully in all patients prior to the ablation procedure and all four pulmonaryvein ostia could be evaluated in 84% of patients. The image quality was excellent in the majority of patients and several variations of the pulmonary vein anatomy could be visualized precisely(e.g., common pulmonary vein ostia, accessory pulmonary veins, varying diameter of the left atrial appendage and its distance to the left superior pulmonary vein). All ablation procedures could be performed as planned and almost all pulmonary veins could be isolated successfully. At 48-mo followup, 68.0% of all patients were free from an arrhythmia recurrence(group A1: 72.7%, group A2: 73.7%, group B: 60.0%). There were no major complications.CONCLUSION3 D TEE provides an excellent overview over the left atrial anatomy prior to AF ablation procedures and these procedures are associated with a favourable long-term outcome.

Trigger elimination of polymorphic ventricular tachycardia and ventricular fibrillation by catheter ablation:trigger and substrate modification

Ventricular fibrillation （VF） is a malignant arrhythmia, usually initiated by a ventricular premature contraction （VPC） during the vulnerable period of cardiac repolarization. Ablation therapy for VF has been described and increasingly reported. Targets for VF triggers are VPCs preceded by Purkinje potentials or from the right ventricular outflow tract （RVOT） in structurally normal hearts, and VPC triggers preceded by Purkinje potentials in ischemic cardiomyopathy. During the session, mapping should be focused on the earliest activation and determining the earliest potential is the key to a successful ablation. However, suppression of VF can be achieved by not only the elimination of triggering VPCs, but also by substrate modification of possible reentry circuits in the Purkinje network, or between the PA and RVOT. The most important issue before the ablation session is the recording of the 12-lead ECG of the triggering event, which can prove invaluable in regionalizing the origin of the triggering VPC for more detailed mapping. In cases where the VPC is not spontaneous or inducible, ablation may be performed by pace mapping. Further studies are needed to evaluate the precise mechanisms of this arrhythmia.

The trend of change in catheter ablation versus antiarrhythmic drugs for the management of atrial fibrillation over time： a meta-analysis and meta-regression

Objective To evaluate the trend of change in the efficacy and safety of catheter ablation compared with antiarrhythmic drug therapy （ADT） for rhythm control in patients with atrial fibrillation （AF） over time. Methods The online databases PubMed and EMBASE were searched for relevant studies. STATA software （version 12.0） was used to perform the meta-analysis and meta-regression. Results Fifteen randomized controlled trials including 2249 patients with AF were identified. The pooled results showed that catheter ablation was associated with a 52% reduction in the risk of AF recurrence compared with ADT [risk ratio （RR） = 0.48, 95% confidence interval （CI）： 0.40-0.57, I2 = 70.7%）. Subgroup analyses showed that catheter ablation exhibited less efficacy in studies after 2011 compared to studies before 2011 （RR = 0.61, 95% CI： 0.54-0.68, I2 = 9.3% and RR = 0.34, 95% CI： 0.24-0.47, I2 = 69.9%, respectively）, and the safety outcome showed a 1.08-fold higher incidence of adverse events （14.2% vs. 7.3%; RR = 1.08, 95% CI： 1.04-1.13） in studies after 2011. Conclusions Catheter ablation appears to be superior to ADT for rhythm control. However, less efficacy and a higher rate of adverse events were observed in studies after 2011 compared to studies before 2011.

Catheter ablation of premature ventricular complexes associated with false tendons: A case report

BACKGROUND False tendon is a common intraventricular anatomical variation. It refers to a fibroid or fibromuscular structure that exists in the ventricle besides the normal connection of papillary muscle and mitral or tricuspid valve. A large number of clinical studies have suggested that there is a significant correlation between false tendons and premature ventricular complexes. However, few studies have verified this correlation during radiofrequency catheter ablation of premature ventricular complexes.CASE SUMMARY A 45-year-old male was admitted to receive radiofrequency ablation for symptomatic premature ventricular complexes. A three-dimensional model of the left ventricle was established by intracardiac echocardiography using the CartoSound^TM mapping system. In addition to the left anterior papillary muscle,the posterior papillary muscle was mapped. False tendons were found at the base of the interventricular septum, and the other end was connected to the left ventricular free wall near the apex. An irrigated touch force catheter was advanced into the left ventricle via the retrograde approach. The earliest activation site was marked at the interventricular septum attachment of the false tendons and was successfully ablated.CONCLUSION This case verified that false tendons can cause premature ventricular complexes and may be cured by radiofrequency ablation guided by intracardiac echocardiography with the Carto Sound TM system.

RADIOFREQUENCY CURRENT CATHETER ABLATION OF THE LEFT ATRIOVENTRICULAR ACCESSORY PATHWAYS WITH PAROXYSMAL SUPRAVENTRICULAR TACHYCARDIA

Seventy patients with left atrioventricular accessory pathways and paroxysmal supraventricular tachycardia(PSVT) underwent radiofrequency catheter ablation(RFCA). The success rate was 94. 3%. Among these patients,26 had manifest preexcitation syndrome, and 44 had concealed preexcitation. Eighteen patients with concealed preexcitation underwent coronary sinus (CS) pacing, and delta wave appeared in 15. The keys to successful RFCA were correct positioning of the radiofrequency(RF) catheter tip, A/V amplitude ratio, AV interval (in sinus rhythm) and VA interval(during SVT or ventricular pacing). After 1～14 months of follow-up. two patients had supraventricular tachycardia(SVT) recurrence.

Percutaneous transhepatic access for catheter ablation of a patient with heterotaxy syndrome complicated with atrial fibrillation:A case report

BACKGROUND Atrial fibrillation(AF)is one of the most common arrhythmias,and radiofrequency catheter ablation is the most effective treatment strategy.The inferior vena cava(IVC)is a common approach for radiofrequency ablation of AF.However,this approach may not be applied to some cases such as chronic venous occlusions,surgical ligation of the IVC,and heterotaxy syndrome(HS).CASE SUMMARY A 68-year-old man with HS suffered from severely symptomatic persistent AF for 9 years,and we successfully ablated by percutaneous transhepatic access.CONCLUSION In patients without femoral vein access,the use of the hepatic vein for pulmonary vein isolation is a viable alternative for invasive electrophysiology procedures.

Catheter ablation for atrial fibrillation in heart failure:untying the Gordian knot

Atrial fibrillation(AF) and heart failure(HF) are complex clinical entities that occur concomitantly in a significant population of patients, and their prevalence is rising in epidemic proportions. Traditionally, both rate and rhythm control strategies have been regarded as equivalent in the management of dysrhythmia in this AF-HF cohort with escalation of treatment largely guided by symptoms. Both disorders are involved in an elaborate pathophysiological interplay with shared cardiovascular risk factors that contribute to the development and sustenance of both AF and HF. Recent studies and continued development of evidence to support catheter ablation for AF has brought into question the traditional belief in equivalence between rate and rhythm control. Indeed, recent trials, in particular the CASTLE-AF(Catheter Ablation versus Standard Conventional Therapy in Patients with Left Ventricular Dysfunction and Atrial Fibrillation) study, suggest that catheter ablation for AF improves survival and rates of hospitalisation in patients with concomitant HF and AF, threatening a paradigm shift in the management of this patient cohort. The evident mortality benefit from clinical trials suggests that catheter ablation for AF should be considered as a therapeutic intervention in all suitable patients with the AF-HF syndrome as these patients may derive the greatest benefit from restoration of sinus rhythm. Further research is needed to refine the evidence base, especially to determine which subgroup of HF patients benefit most from catheter ablation and what is the optimal timing.

A virtual reality based surgical skills training simulator for catheter ablation with real-time and robust interaction

Background Atrial fibrillation(AF)is the most common sustained cardiac arrhythmia that can cause severe heart problems.Catheter ablation is one of the most ideal procedures for the treatment of AF.Physicians qualified to perform this procedure need to be highly skilled in manipulating the relevant surgical devices.This study proposes an interactive surgical simulator with high fidelity to facilitate efficient training and low-cost medical education.Methods We used a shared centerline model to simulate the interaction between multiple surgical devices.An improved adaptive deviation-feedback approach is proposed to accelerate the convergence of each iteration.The periodical beating of the human heart was also simulated in real time using the position-based dynamics(PBD)framework to achieve higher fidelity.We then present a novel method for handling the interaction between the devices and the beating heart mesh model.Experiments were conducted in a homemade simulator prototype to evaluate the robustness,performance,and flexibility of the proposed method.Preliminary evaluation of the simulator was performed by medical students,residents,and surgeons.Results The interaction between surgical devices,static vascular meshes,and beating heart mesh was stably simulated in a frame rate suitable for interaction.Conclusion Our simulator is capable of simulating the procedure of catheter ablation with high fidelity and provides immersive visual experiences and haptic feedback.

Long-term stroke rates after catheter ablation or antiarrhythmic drug therapy for atrial fibrillation： a meta-analysis of randomized trials

Background Atrial fibrillation （AF） is an independent risk factor for ischemic stroke and is associated with increased risk of death. Randomized studies suggest improved quality of life for patients with AF after successful catheter ablation compared to antiarrhythmic drug therapy. The value of ablation in long-term risk of ischemic stroke, however, has not been assessed. We conducted a meta-analysis to determine whether AF ablation reduces the long-term risk of stroke compared to antiarrhythmic drug therapy in randomized controlled trials. Methods ＆ Results PubMed and the Cochrane Central Register were searched for randomized trials from January 1990 to December 2014 comparing AF catheter ablation to drug therapy. The results are reported as risk differences （RDs） and 95% CI. Thirteen trials were analyzed with 1097 patients treated by catheter ablation and 855 patients received antiarrhythmic drug therapy. Overall, seven patients （0.64%） in the catheter ablation group had ischemic stroke or transient ischemic attacks vs. two patients （0.23%） in the drug therapy group. No difference was shown in the rate of stroke or transient ischemic attack between ablation and drug therapy （RD： 0.003, 95% CI： -0.006 to 0.012, P = 0.470）, and no evidence of heterogeneity was observed （I^2 = 0, P = 0.981）. No potential publication bias was found. There was also no difference in mortality between the two groups （RD： -0.004, 95% CI： -0.014 to 0.006, P = 0.472）. Conclusions This meta-analysis of randomized controlled trials showed similar rates of ischemic stroke or transient ischemic attack and death in AF patients undergoing catheter ablation compared to drug therapy. A larger prospective randomized trial to confirm this finding is warranted.

RADIOFREQUENCY CATHETER ABLATION OF PERMANENT ATRIAL FIBRILLATION UNDER GUIDANCE OF CARTO-MERGE TECHNIQUE

Objective To investigate the feasibility and effectiveness of radiofrequency catheter ablation (RFCA) to treat permanent atrial fibrillation (AF) under the guidance of Carto-Merge technique. Methods Fifteen male patients with permanent AF underwent RFCA under the guidance of Carto-Merge technique. The mean age was 54.00±10.44 years, and duration of AF was 23.66±14.93 months. Cardiac magnetic resonance angiography (MRA) was performed to obtain pre-procedural three-dimensional (3D) images on the anatomy of left atrium (LA) and pulmonary veins (PVs) before RFCA procedure. Then the electroanatomical map was integrated with 3D images of MRA to form Carto-Merge map that guided step-by-step ablation strategy of permanent AF. Circumferential PV ablation was performed first until complete PVs electric isolation confirmed by Lasso catheter. If AF was not terminated, lesion lines on roof of LA, mitral isthmus, and tricuspid isthmus were produced. Results The episodes of AF were terminated during RFCA in 2 patients, by direct current cardioversion in the remaining 13 patients. Transient AF occurred in 2 patients after ablation on 1st day and 1st week respectively, AF terminated spontaneously not long after taking metoprolol. One patient developed persistent atrial flutter (AFL) in 2 months after procedure and AFL was eliminated by the second ablation. Persistent AF recurred on 1st day, 1st and 5th week respectively in 3 patients, and did not terminate after 3 months even though amiodarone was given. The remaining 12 patients were all free of AF during 2-11 months of follow-up. The recent success rate for RFCA of permanent AF was 80%. Conclusions Carto-Merge technique can effectively guide RFCA of permanent AF. When combined with single Lasso mapping, it can simplify the mapping, lower expenses, and enhance the success rate of RFCA of permanent AF.

Delayed papillary muscle rupture after radiofrequency catheter ablation: A case report

BACKGROUND With an increased number of surgical procedures involving the mitral annular region,the risk of mitral valve prolapse(MVP)has also increased.Previous studies have reported that worsening of MVP occurred early after radiofrequency catheter ablation(RFCA)at papillary muscles in ventricular tachycardia(VT)patients with preoperative MVP.CASE SUMMARY We report a case where MVP and papillary muscle rupture occurred 2 wk after RFCA in a papillary muscle originated VT patient without mitral valve regurgitation or prolapse before.The patient then underwent mitral valve replacement with no premature ventricular contraction or VT.During the surgery,a papillary muscle rupture was identified.Pathological examination showed necrosis of the papillary muscle.The patient recovered after mitral valve replacement.CONCLUSION Too many ablation procedures and energy should be avoided.

Effect of pretreatment with aspirin and ticlopidine on the change of platelet aggregability after radiofrequency catheter ablation

Eighty-two patients with supraventricular tachycardia undergoing radiofrequency catheter ablation (RFCA) were studied to observe the inhibition effect of aspirin and ticlopidine on platelet aggregability (PAG) and thromboxane B 2(TXB 2) of the blood samples. Patients were divided into aspirin group A, ticlopidine group B, aspirin+ticlopidine group C and control group D. PAG and TXB 2 were increased clearly after RFCA in all groups (P<0.001). Treatment with aspirin or ticlopidine before operation could reduce the platelet aggregability caused by RFCA and the joint effect of two drugs(change rate of group A:52.51±12.51%; group B:54.78±11.27%;group C: 30.51±10.59%;group D:91.75±21.43%; P<0.05)was studied. The much decreased platelet aggregability after antiplatelet therapy was evidence of the potential benefit of the treatment in preventing thromboembolism after ablation. Pretreatment with aspirin and ticlopidine together is a good way to decrease palatelet aggregability after RFCA.

Clinical utility of left atrial strain in predicting atrial fibrillation recurrence after catheter ablation: An up-to-date review

Rhythm control is the core part of the integrated management of atrial fibrillation(AF),especially in the early stages.Despite advances in catheter ablation(CA),the recurrence rate of AF after CA remains high.As a result,stratification and early management of AF recurrence after CA are critical.Currently,predictors of recurrence of AF after CA are mostly based on dysfunction caused by structural remodeling,apart from traditional risk factors.Atrial strain is a recently developed important parameter for detecting the deformability of atrial myocardium during the cardiac cycle prior to atrial remodeling.Although there is only preliminary evidence,atrial strain is still a promising parameter in predicting the recurrence of AF after CA at an early stage.This review focuses on the evaluation of atrial strain,the current applications of atrial strain in assessing atrial function,and predicting the recurrence of AF after CA.We summarize the contents related as follows:(1)CA for rhythm control in AF;(2)Evaluation methods of atrial strain;(3)Atrial strain in the remodeling and reverse remodeling of AF;and(4)Clinical applications of atrial strain in predicting the recurrence of AF after CA.Although there is accumulating evidence on the role of decreased atrial strain in the early prediction of AF recurrence,atrial strain is limited in clinical practice for lacking exact cut-off values and difficulty in distinguishing specific function phases of the atrium.More research is needed in the future to add strength to the early prediction value of atrial strain in AF recurrences.

The correlation between MFAP4 and recurrence and clinical outcome of atrial fibrillation after radiofrequency catheter ablation

Objective:To investigate the correlation between Microfibrillar-associated protein 4(MFAP4)and recurrence and clinical outcome of atrial fibrillation(AF)after radiofrequency catheter ablation(RFCA).Methods:A total of 101 patients with AF admitted to our department from December 2018 to January 2020 were treated with RFCA.The average follow-up period was(11.91±0.38)months.They were divided into recurrence group and non-recurrence group according to whether they had recurrence of AF.The levels of MFAP4,transforming growth factor-β1(TGF-β1),cardiac ultrasound indexes,body mass index(BMI)and major cardio-cerebral vascular events were compared between the two groups.The receiver operating characteristic(ROC)curve was drawn to analyze the predictive value of MFAP4 for recurrence of AF after RFCA.Results:The levels of MFAP4,TGF-β1,left atrial diameter(LAD)and BMI in the recurrent group were higher than those in the non-recurrent group(P<0.05).The left ventricular ejection fraction(LVEF)in the recurrent group was lower than that in the non-recurrent group(P<0.05).The levels of MFAP4,TGF-β1 and LAD in the patients of recurrent paroxysmal AF and persistent AF after RFCA were higher than those in the respective non-recurrent patients(P<0.05).MFAP4 was positively correlated with TGF-β1 and LAD(P<0.05).Logistic regression analysis showed that MFAP4,TGF-β1,and LAD were independent risk factors for recurrence of AF after RFCA.The ROC curve analysis showed that the area under the ROC curve of MFAP4 for predicting recurrence of AF after RFCA was 0.888(P=0.000),and the optimal cut-off value was 19.295ng/ml,with a sensitivity of 77.3%and a specificity of 77.2%.The incidence of readmission and total adverse events in recurrence group was significantly higher than that in non-recurrence group(P<0.05).Conclusions:MFAP4 was significantly increased in patients with recurrence after RFCA of AF,which was one of the independent risk factors for recurrence after RFCA of AF,and had certain clinical application value.

Application Effect Evaluation of Telmisartan combined with Spironolactone after Catheter Ablation of Patients with Paroxysmal Atrial Fibrillation

Objective:To evaluate the application effect of telmisartan combined with spironolactone after catheter ablation of patients with paroxysmal atrial fibrillation.Methods:80 cases of patients with paroxysmal atrial fibrillation who received radiofrequency catheter ablation treatment from March 2013 to March 2016 in our hospital were randomly selected,these patients were divided into two groups according to the treatment methods,namely,the telmisartan with Spironolactone treatment group(combined treatment group,n=40)and the conventional therapy group(n=40).The hs-CRP,NT-proBNP,LAD and recurrence of the two groups were analyzed.Results:The hs-CRP,NT-proBNP levels after 3 months of the combined treatment group were significantly lower(P<0.05),the recurrence rate 10.0%(4/40)was significantly lower than the conventional therapy group 27.5%(11/40)(P<0.05),the time to recurrence was significantly longer than the conventional therapy group(P<0.05).Conclusion:The application effects of telmisartan combined with spironolactone after catheter ablation in the treatment of patients with paroxysmal atrial fibrillation are better than conventional therapy.