Nomogram predicting the prognosis of primary liver cancer after radiofrequency ablation combined with transcatheter arterial chemoembolization

BACKGROUND The incidence and mortality rates of primary hepatocellular carcinoma(HCC)are high,and the conventional treatment is radiofrequency ablation(RFA)with transcatheter arterial chemoembolization(TACE);however,the 3-year survival rate is still low.Further,there are no visual methods to effectively predict their prognosis.AIM To explore the factors influencing the prognosis of HCC after RFA and TACE and develop a nomogram prediction model.METHODS Clinical and follow-up information of 150 patients with HCC treated using RFA and TACE in the Hangzhou Linping Hospital of Traditional Chinese Medicine from May 2020 to December 2022 was retrospectively collected and recorded.We examined their prognostic factors using multivariate logistic regression and created a nomogram prognosis prediction model using the R software(version 4.1.2).Internal verification was performed using the bootstrapping technique.The prognostic efficacy of the nomogram prediction model was evaluated using the concordance index(CI),calibration curve,and receiver operating characteristic RESULTS Of the 150 patients treated with RFA and TACE,92(61.33%)developed recurrence and metastasis.Logistic regression analysis identified six variables,and a predictive model was created.The internal validation results of the model showed a CI of 0.882.The correction curve trend of the prognosis prediction model was always near the diagonal,and the mean absolute error before and after internal validation was 0.021.The area under the curve of the prediction model after internal verification was 0.882[95%confidence interval(95%CI):0.820-0.945],with a specificity of 0.828 and sensitivity of 0.656.According to the Hosmer-Lemeshow test,χ^(2)=3.552 and P=0.895.The predictive model demonstrated a satisfactory calibration,and the decision curve analysis demonstrated its clinical applicability.CONCLUSION The prognosis of patients with HCC after RFA and TACE is affected by several factors.The developed prediction model based on the influencing parameters shows a good prognosis predictive efficacy.

Radiofrequency ablation combined with transcatheter arterial chemoembolization for recurrent liver cancer

BACKGROUND The recurrence rate of liver cancer after surgery is high.Radiofrequency ablation(RFA)combined with transcatheter arterial chemoembolization(TACE)is an effective treatment for liver cancer;however,its efficacy in recurrent liver cancer remains unclear.AIM To investigate the clinical effect of TACE combined with RFA in the treatment of recurrent liver cancer.METHODS Ninety patients with recurrent liver cancer were divided into 2 groups according to treatment plan:Control(RFA alone);and experimental[TACE combined with RFA(TACE+RFA)].The incidence of increased alanine aminotransferase levels,complications,and other indices were compared between the two groups before and after the procedures.RESULTS One month after the procedures,the short-term efficacy rate and Karnofsky Performance Status scores of the experimental group were significantly higher than those of the control group(P<0.05).Alpha-fetoprotein(AFP)and total bilirubin levels were lower than those in the control group(P<0.05);The overall response rate was 82.22%and 66.67%in the experimental and control groups,respectively;The disease control rate was 93.33%and 82.22%in the experimental and control groups,respectively,the differences are statistically significant(P<0.05).And there were no statistical differences in complications between the two groups(P>0.05).CONCLUSION TACE+RFA was effective for the treatment of recurrent liver cancer and significantly reduced AFP levels and improved various indices of liver function.

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.

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.

Clinical Study on the Treatment of 325 Cases of Atrioventricular Node Reentrant Tachycardia by Radiofrequency Catheter Ablation

In order to improve the efficacy of modified inferior method or middle method of radiofrequency catheter ablation (RFCA) in the treatment of atrioventricular node reentrant tachycardia (AVNRT), the clinical data of 325 cases of AVNRT from March 1992 to Feb. 2000 being subjected to the treatment of RFCA were retrospectively analyzed. The results showed that the successful rate was increased and recurrence was decreased year by year. In the recent 4 years the effective rate was up to 100 %. The complication of three grade of AVB occurred in 3 % and recurrent rate in 9.1 % before March 1996, but both of them were zero in the last 3 years. The time of RFCA procedure and X ray exposure was significantly reduced. It was concluded that ablating more than 3 targets by modified inferior method or middle method with energy titrating and strict endpoint was the crux of obtaining satisfactory therapeutic effects and preventing recurrence.

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.

Radiofrequency catheter ablation of atrial tachycardias related to myocardial scar or incision

Objectives Intra-atrial re-entrant tachycardias(IARTs)are common late after heart surgery.Conventional mapping and ablation is relatively difficult because of the complicated anatomy and multiple potential re-entry loops.In this study we aimed to evaluate the electrophysiological characteristics and radiofrequency catheter ablation of atrial tachycardia(AT)induced by myocardial scar or incision.Methods In 6 patients(three male and three female,aged 33.3±11.8 years)who had AT related to myocardial scar or incision, electrophysiological study and radiofrequency catheter ablation(RFCA)were performed.Earliest activation combined with entrain- ment mapping was adopted to determine a critical isthmus.Results Re-entry related to the lateral atriotomy scar was inducible in 5 of 6 patients.With entrainment mapping,the PPI(post-pacing interval)-TCL(tachycardia cycle length)difference was＜30 ms when pacing at the inferior margins of the right lateral atriotomy scar.Among them,3 patients had successful linear ablation between scar area to inferior vena cava,and 2 patients between scar area to tricuspid annulus.Re-entry involving an ASD patch was demonstrated in 1 of 6 patients.PPI-TCL differences＜30 ms were observed when entraining tachycardia at sites near the septal patch.But linear ablation failed in terminating AT.There was no complication during procedure.No recurrence of AT related to incision was observed during follow-up except for the failed patient.Conclusion Under conventional electrophysiological mapping,adopting linear ablation from scar area to anatomic barrier,successful ablation can be obtained in patients with IRATs related to myocardial scar or incision.

Efficacy and safety of percutaneous transhepatic biliary radiofrequency ablation in patients with malignant obstructive jaundice

BACKGROUND Percutaneous transhepatic cholangiodrainage(PTCD)and endoscopic retrograde cholangiopancreatography/endoscopic nasobiliary drainage are the most common clinical procedures for jaundice control in patients with unresectable malignant obstructive jaundice,yet the safety and effect of endobiliary radiofrequency ablation(EB-RFA)combined PTCD is rarely reported,in this article,we report our experience of EB-RFA combined PTCD in such patients.AIM To retrospectively study the efficacy and safety of EB-RFA combined PTCD in patients with unresectable malignant obstructive jaundice.METHODS Patients with unresectable malignant obstructive jaundice treated with EB-RFA under PTCD were selected,the bile ducts of the right posterior lobe was selected as the target bile ducts in all cases.The general conditions of all patients,preoperative tumour markers,total bilirubin(TBIL),direct bilirubin(DBIL),albumin(ALB),alkaline phosphatase(ALP),and glutamyl transferase(GGT)before and on the 7th day after the procedure,as well as perioperative complications,stent patency time and patient survival were recorded.RESULTS All patients successfully completed the operation,TBIL and DBIL decreased significantly in all patients at the 7th postoperative day(P=0.009 and 0.006,respectively);the values of ALB,ALP and GGT also decreased compared with the preoperative period,but the difference was not statistically significant.Perioperative biliary bleeding occurred in 2 patients,which was improved after transfusion of blood and other conservative treatments,pancreatitis appeared in 1 patient after the operation,no serious complication and death happened after operation.Except for 3 patients with loss of visits,the stent patency rate of the remaining 14 patients was 100%71%and 29%at the 1^(st),3^(rd),and 6^(th)postoperative months respectively,with a median survival of 4 months.CONCLUSION EB-RFA under PTCD in patients with unresectable malignant obstructive jaundice has a satisfactory therapeutic effect and high safety,which is worthy of further clinical practice.

Radiofrequency catheter ablation of ventricular tachycardia in a patient with dermatomyositis

A 51-year old male who presented at our hospital for recurrent palpitation for several months was diagnosed dermatomyositis ten years ago and had interstitial lung disease since two years ago. Recently, he was admitted for atypical hepatitis, and received maintenance treatment of oral corticosteroids.

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.

Radiofrequency Catheter Ablation Of Inappropriate Sinus Tachycardia

Objective:To investigate the mechanism of inappropriate sinustachycardia and the safety,effectiveness on radiofrequency catheterablation of it.Methods:Radiofrequency catheter ablation wasperformed on a 52-year-old female patient and changes in Holter,heart rate variability,intrinsic heart rate and syndromes were comparedbetween before and after radiofrequeney catheter ablation.Results:The inappropriate sinus tachycardia could not be induced and terminatedby atrial program electric stimulation and burst stimulation,whichsuggests that the mechanism of inappropriate sinus tachycardia isreentry.After radiofrequency catheter ablation,the total heart beatsdecreased from 173490 to 129172 times,the lowest heart rate did from79 to 71 bpm,the highest heart rate from 200 to 122 bpm,the averageheart rate from 117 to 90 bpm,and intrinsic heart rate from 166 to 93Variables of heart rate variability varied too.PNN50 increased from O to11,RMSSD did from 8 to 35.However,LF/HF ratio decreased from12.23 to 0.86.Transesophageal eleetrophysiologic studies demonstratethat sinoatrial node function is normal after radioflequency catheterablation.The patient has been followed up for six months,she has beenbeing free of palpitation,chest distress and dizziness,etc.Conclusion:The inappropriate sinus tachycardia could be due to abnormal sinoatrialnodal automaticity resulting from excessive sympathetic nerve influencesor deficient vagal nerve influences and modification of sinus node withradiofrequency catheter ablation is a safe,effective method for thetreatment of inappropriate sinus tacbycardia.

RADIOFREQUENCY CATHETER ABLATION FOR TREATMENT OF ATRIAL ARRHYTHMIAS

In this paper,electrophysiologic study and RFCA were attempted in 3 patientswho had clinical episodes of atrial arrhythmias with multiple ECG recordings.Diagnoses were automatic atrial tachycardia in one,reentrant atrialtachycardia in one,and typical atrial flutter in one.Site for atrial flutterablation was based on anatomic barriers in the floor of the right atrinm.Forautomatic atrial tachycardia,the site of earliest activation before the pwave was sought and for reentrant atrial tachycardia,our goal was to identifya site of early activation in a zone of slow conduction.At target sites,20 to40w of radiofrequency energy were delivered during tachycardia.Procedureend point was inability to reinduce tachycardia by atrial pacing and infusionof isoproterenol,Acute success was achieved in all of three patients.Fortachycardia involves reentry(reentrant atrial tachycardia and atrial flutter),successful ablation required severing an isthmus of slow conduction.Foratrial flutter,this was between the tricuspid annulus and the coronary sinus osor between the inferior vena cava and the tricuspid annulus.Abla-tioo ofautomatic and reentrant atrial tachycardia and atrial flutter had a highsuccess rate and caused no complications.Repeat procedures may be requiredfor long-term success,especially in patient with atrial flutter.

RADIOFREQUENCY CATHETER ABLATION IN 66 CASES WITH REENTRANT PAROXYSMAL SUPERVENTRICULAR TACHYCARDIA

Sixty-six cases with reentrant supraventricular tachycardias were treatedby radiofrequency current cather ablation(RFCA).Forty one patients withatrioventricular reentrant tachycardia(male 30,femal 11,Group Ⅰ),Twenty fivepatients with atrloventricular nodal reentrant tachycaria(male 8,femal 17,Group Ⅱ).Group 1.41 patients had 43 accessory pathways(APs)of which23 located at left free wall(53.5),6 at left posteroseptal region(13.9%),14 atright free wall(32.6%).Successful RFCA were 26 in 27 cases with leftAPs(96.3%),14 in 14 cases with right APs(100%).In group 11.13 patientswith slow pathway were ablated,success rate is 92.3.The characteristics of local electrocardlogram at the ablation target sitewere:(1)A/V ratlo【1.(2)AV or VA Interval【40ms.(3)V-delta Interval】20ms.the 95%ablation target sites were slmler to this characteristics in oursuccessful RFCA.During a follow up of 1-7months,no Patients hadexparienced recurrence of arrhythmia.

Benefits and drawbacks of radiofrequency ablation via percutaneous or minimally invasive surgery for treating hepatocellular carcinoma

The management of early stage hepatocellular carcinoma(HCC)presents significant challenges.While radiofrequency ablation(RFA)has shown safety and effectiveness in treating HCC,with lower mortality rates and shorter hospital stays,its high recurrence rate remains a significant impediment.Consequently,achieving improved survival solely through RFA is challenging,particularly in retrospective studies with inherent biases.Ultrasound is commonly used for guiding percutaneous RFA,but its low contrast can lead to missed tumors and the risk of HCC recurrence.To enhance the efficiency of ultrasound-guided percutaneous RFA,various techniques such as artificial ascites and contrast-enhanced ultrasound have been developed to facilitate complete tumor ablation.Minimally invasive surgery(MIS)offers advantages over open surgery and has gained traction in various surgical fields.Recent studies suggest that laparoscopic intraoperative RFA(IORFA)may be more effective than percutaneous RFA in terms of survival for HCC patients unsuitable for surgery,highlighting its significance.Therefore,combining MIS-IORFA with these enhanced percutaneous RFA techniques may hold greater significance for HCC treatment using the MIS-IORFA approach.This article reviews liver resection and RFA in HCC treatment,comparing their merits and proposing a trajectory involving their combination in future therapy.

Electrophysiologic Mechanism and Radiofrequency Catheter Ablation of Incessent Atrioventricular Reentrant Tachycardia

Objective\ To study electrophysiologic mechanism and radiofrequency catheter ablation of incessent atrioventricular reentrant tachycardia. Methods\ In this report, 17 cases of incessant atrioventricular reentrant tachycardia (IAVRT) were presented. There were twelve men and five women. The average age was (46±17) years. Mean duration of persistent tachycardia was (36±76) days. Mean ventricular rate was (180±17) min\+\{-1\} during tachycardia. Five patients had cardiac dysfunction and four had tachycardia induced dilated cardiomyopathy. Results\ All the 17 patients underwent successful radiofrequency catheter ablation. There were eleven accessory pathways(APs) in the left side posteroseptal position, three in the left free wall, two in the right free wall and one in the right side posteroseptal position. Two Aps had decremental conduction characteristics. Four patients had longer than normal atrioventricular conduction time, mean AH interval being (161±6) ms. Six patients had posteroseptal AP with RP≥PR during tachycardia on the surface ECG. All patients were free of symptomatic tachycardia during follow up period of 1 38 months. Five patients with heart dysfunction ameliorated one week after tachycardia ablated. Four tachycardia induced dilated cardiomyopathies were followed for mean of 12 months, the size and function of the heart returned normal in three patients, and the heart size became smaller in one. Conclusion\ It was concluded that electrophysiologic mechanism of IAVRT could be related to the following factors: ①Position of the AP, posteroseptal AP had the highest incidence of IAVRT; ②Characteristics of AP, AP with RP≥PR during tachycardia on the surface ECG and the decremental conduction was liable to IAVRT; ③Longer atrioventricular conduction time. As previously described, one or more factors can lead to IAVRT. Radiofrequency catheter ablation could eradicate IAVRT and cure IAVRT induced dilated cardiomyopathy.

Clinical outcomes of radiofrequency catheter ablation of atrial fibrillation in octogenarians lO-year experience of a one high-volume center

Background Prevalence of atrial fibrillation （AF） increases with age. Radiofrequency catheter ablation （RFCA） is an establishedtreatment option superior to antiarrhythmics （AAs）. In this study, we investigated safety and efficacy of RFCA of AF in octogenarians.Methods From our database, we extracted procedural and follow-up data for patients 〉 80 years with symptomatic AF undergoing RFCAand compared this population to RFCA patients 〈 50 years. All patients underwent pulmonary vein isolation （PVI） supplemented by linearlesions in PVI-nonresponders. Arrhythmia-free survival was assessed using seven day Holter every three months post procedure. All patientscompleted their 12 months follow-up. Results Fifty patients aged ≥80 years （80.5 ± 1.6 years） were compared to 259 patients aged 〈 50years （43.5±5.5 years）. The RFCA complication rate did not vary between groups. No differences in procedural characteristics were seenafter being analyzed by type of AF. Among patients with paroxysmal AF, 71.4% octogenarian vs. 84.7% young patients was free of anyarrhythmia, without AAs, after single procedure. For non-paroxysmal AF, arrhythmia-free survival without AAs, was considerably lower（58.6% octogenarians vs. 81.2% younger patients, P = 0.023）. If AAs were used, arrhythmia-free survival for paroxysmal AF increased to90.5% and 92.1% in octogenarians and younger patients, respectively; and in non-paroxysmal AF it increased to 79.3% vs. 88.4%. ConclusionsRFCA is a safe and effective strategy to achieve normal sinus rhythm in a highly selected group of octogenarians. Paroxysmal AF ablation inoctogenarians has similar clinical effectiveness as that seen in much younger patients. Non-paroxysmal AF ablation has lower, but still rea-sonable clinical effectiveness.

Value of cystatin C in predicting atrial fibrillation recurrence after radiofrequency catheter ablation

Backgroud Recent studies have demonstrated that cystatin C is a valuable risk marker for cardiovascular disease morbidity and mortality.Therefore,we hypothesized that the pre-ablation cystatin C level was associated with post-ablation atrial fibrillation(AF)recurrence.Methods 207 patients were enrolled and completed in this prospective observational study.Patients with AF scheduled for receive radiofrequency catheter ablation(RFCA)therapy were screened for the study.Before ablation therapy,electrocardiogram,24 h holter monitor,transesophageal echocardiography,serum cystatin C,high-sensitivity C-reactive protein,creatinine levels,and routine blood examinations were examined.After ablation,patients were followed up every week for the first month,and then at 2,3,6,9,and 12 months.Thereafter,patients came back to out-patient clinic every six months regularly.Electrocardiogram or 24 h holter monitor were repeated if the patient experienced palpitations or every six months.AF recurrence was defined as atrial flbrillation/atrial flutter or atrial tachycardia lasting≥30 seconds within three months after therapy.Results Compared to patients with no AF recurrence,patients with recurrence had longer AF history(P=0.007),more early recurrence(P=0.000),a larger left atrium(P=0.004),and higher pre-ablation cystatin C levels(P=0.000).Multivariate regression analysis revealed that cystatin C and left atria(LA)diameter were risk factors for AF recurrence.After adjusting for LA diameter,the risk of AF recurrence increased 30%with every milligram cystatin C elevation(95%CI:1.117-1.523).Conclusions Pre-ablation cystatin C levels were associated with AF recurrence after RFCA therapy,an optimal cut-off value of 1.190 mg/L(sensitivity=0.576;specificity=0.851).

Catheter ablation of atrial fibrillation: Radiofrequency catheter ablation for redo procedures after cryoablation

AIM: To evaluate the effectiveness of two different strategies using radiofrequency catheter ablation for redo procedures after cryoablation of atrial fibrillation.METHODS: Thirty patients(paroxysmal atrial fibrillation: 22 patients,persistent atrial fibrillation: 8 patients) had to undergo a redo procedure after initially successful circumferential pulmonary vein(PV) isolation with the cryoballoon technique(Arctic Front Balloon,CryoCath Technologies/Medtronic).The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy(CARTO;Biosense Webster) depending on the intra-procedural findings.After discharge,patients were scheduled for repeated visits at the arrhythmia clinic.A 7-day Holter monitoring was performed at 3,12 and 24 mo after the ablation procedure.RESULTS: During the redo procedure,a mean number of 2.9 re-conducting pulmonary veins(SD ± 1.0 PVs) were detected(using a circular mapping catheter).In 20 patients,a segmental approach was sufficient to eliminate the residual pulmonary vein conduction because there were only a few recovered pulmonary vein fibres.In the remaining 10 patients,a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction.All recovered pulmonary veins could be isolated successfully again.At 2-year follow-up,73.3% of all patients were free from an arrhythmia recurrence(22/30).There were no major complications.CONCLUSION: In patients with an initial circumferential pulmonary vein isolation using the cryoballoon technique,a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation.