Chronic Success Rate Research Articles

Trans-jugular approach for safe and successful cryoablation of para-Hisian/anterior-septal, anterior, and anterior-lateral accessory pathways in children.

Cryoablation of APs localized near the atrioventricular (AV) junction is a well-established ablation strategy in children, and it has proved to be very safe. However, recurrence rates remain considerable for specific accessory pathway (AP) localizations. The aim of this retrospective study was to evaluate the efficacy and safety of a trans-jugular approach for cryoablation of right anterior, anterior-lateral, and anterior-septal APs in children, as compared to the conventional femoral approach. From June 2019 to November 2023, 24 consecutive patients (mean age 13.2 ± 4.6, 12 males (50% of total cohort)) with right anterior-lateral, anterior, and anterior-septal/para-Hisian APs underwent 3D non-fluoroscopic transcatheter cryoablation through the right jugular vein at our Institution. Ablation results were compared with 24 patients for whom a conventional trans-femoral approach was used. Acute procedural success rate was 100% (n = 24/24), with a non-statistically significant difference as compared to the control group (100% vs. 83%, p = 0.1). During follow-up (1.1 years, interquartile range 0.6-1.3), one patient (4%) had a recurrence in the trans-jugular group, as opposed to eight (38%) in the control group (p = 0.006). No permanent complications occurred. 3D cryoablation of right anterior-lateral, anterior, and anterior-septal/para-Hisian APs in children using a trans-jugular approach is extremely effective and safe, resulting in higher chronic success rate compared to the conventional femoral approach.

The use of minimal fluoroscopy for cardiac electrophysiology procedures: A meta-analysis and review of the literature.

BackgroundConventional catheter ablation involves prolonged exposure to ionizing radiation, potentially leading to detrimental health effects. Minimal fluoroscopy (MF) represents a safer alternative, which should be explored. Data on the safety and efficacy of this technique are limited.HypothesisOur hypothesis is that MF is of equal efficacy and safety to conventional catheter ablation with the use of fluoroscopy by performing a meta‐analysis of both randomized controlled trials (RCTs) and real‐world registry studies.MethodsPubmed and Embase were searched from their inception to July 2020 for RCTs, cohort and observational studies that assessed the outcomes of catheter ablation using a MF technique versus the conventional approach.ResultsFifteen studies involving 3795 patients were included in this meta‐analysis. There was a significant reduction in fluoroscopy and procedural time with no difference in acute success (odds ratio [OR]:0.74, 95% CI: 0.50–1.10, p = .14), long‐term success (OR:0.92, 95% CI: 0.65–1.31, p = .38), arrhythmia recurrence (OR:1.24, 95% CI: 0.75–2.06, p = .97) or rate of complications. (OR:0.83, 95% CI: 0.46–1.48, p = .65). Additionally sub‐group analysis for those undergoing catheter ablation for atrial fibrillation (AF) did not demonstrate a difference in success or complication rates (OR:0.86, 95% CI: 0.30–2.42, p = .77). Multivariate meta‐regression did not identify the presence of moderator variables.ConclusionThis updated meta‐analysis demonstrated an overall reduction in procedural and fluoroscopy time for those undergoing a minimal fluoroscopic approach. There was no significant difference in either acute or chronic success rates or complications between a MF approach and conventional approach for the management of all arrhythmias including those undergoing catheter ablation for AF.

The Short and Long-Term Efficacy of Pulmonary Vein Isolation as a Sole Treatment Strategy for Paroxysmal Atrial Fibrillation: A Systematic Review and Meta-Analysis.

Background:Pulmonary vein isolation (PVI) is an accepted treatment strategy for catheter ablation (CA) of paroxysmal atrial fibrillation (PAF). In this study, we aimed to assess the short, mid- and long-term outcome of PVI as a sole treatment strategy for PAF.Methods:Six bibliographic electronic databases were searched to identify all published relevant stud-ies until December 14, 2015. Search of the scientific literature was performed for studies describing outcomes with mean follow-up > 24 months after PAF ablation. Only articles with 1, 3 or 5-year fol-low up were included, from the same group of investigators.Results:Of the 2398 references reviewed for eligibility, 13 articles (enrolling a total of 1774 patients) were included in the final analysis. Pooled analysis showed that the 12- and 62 -month success rate of a single CA procedure was 78% (95% CI 0.76% to 0.855) and 59% (95% CI 0.56% to 0.64%), re-spectively. The results did not differ by type of CA performed. Major complications mentioned in the enrolled studies were cerebrovascular event, pericardial tamponade and PV stenosis.Conclusion:There is a progressive and significant decline in freedom from AF between 1, 3 and 5-year after successful PVI in patients with PAF. Our analysis suggests that a high short-time success rate after PVI does not necessarily result in high chronic success rate.

Effectivity of left atrial appendage occlusion with AtriClip in 155 consecutive patients – Single center study

ObjectivesLeft atrial appendage (LAA) plays a crucial role in the etiopathogenesis of the stroke in patients with non-valvular atrial fibrillation. Different methods of surgical occlusion of the LAA have been associated with different levels of acute and chronic success rate. This paper presents our experience with LAA occlusion using the AtriClip. Methods155 patients undergoing cardiac surgery procedures with epicardial AtriClip exclusion of the LAA were enrolled in the study. The AtriClip was placed via a sternotomy, thoracotomy or from a thoracoscopic approach. Postoperative variables such as thromboembolic events, clip stability, and endocardial leakage around the device were examined by transesophageal echocardiography (TEE) and/or computed tomography (CT). Patients were then contacted via telephone and questionnaire regarding episodes of stroke and actual anticoagulation therapy was completed. ResultsAvg. age of the study population was 66.9 years (102 males). Clip was implanted from sternotomy or thoracotomy in 77 patients and from thoracoscopy in 78 patients. The perioperative success rate of clip implantation was achieved in 98% of patients. 10 patients (6.4%) were revised for bleeding, but none of the revisions were due to clip implantation. During the hospitalization and follow-up period, consisting of 2422 patient-months, 4 of the cardiac patients experienced transitory ischemic attacks and 2 patients experienced a cerebrovascular attack. ConclusionsEpicardial clip exclusion of the LAA appears to be a reproducible and safe surgical method with a high success rate. Our follow-up confirmed clip stability, complete occlusion of the LAA, and absence of any AF-related thromboembolic events. These results support regular usage of AtriClip during LAA closure.

HotBalloon Ablation of the Pulmonary Veins for Paroxysmal AF: A Multicenter Randomized Trial in Japan

BackgroundPoint-by-point catheter ablation is an established treatment for drug-refractory paroxysmal atrial fibrillation (PAF). However, it is time consuming, requires excellent technique to achieve complete pulmonary vein (PV) isolation, and is associated with severe complications. ObjectivesThe purpose of this study was to evaluate the safety and effectiveness of a HotBalloon ablation (HBA) compared with antiarrhythmic drug therapy (ADT) for the treatment of PAF. MethodsA prospective multicenter randomized controlled study was conducted in Japan. Patients with symptomatic PAF refractory to antiarrhythmic drugs (Class I to IV) were randomized to HBA or ADT at a 2:1 ratio and assessed for effectiveness in a comparable 9-month follow-up period. ResultsA total of 100 patients in the HBA group and 43 patients in the ADT group received treatment at 17 sites. HBA procedure produced acute complete PV isolation in 98.0% (392 of 400) of the PVs and in 93.0% (93 of 100) of patients in the HBA group. The chronic success rates after the 9-month effective evaluation period were 59.0% in the HBA group (n = 100) and 4.7% in the ADT group (n = 43; p < 0.001). The incidence of major complications was 11.2% (15 of 134 patients). The incidences of PV stenosis (>70%) and transient phrenic nerve injury were 5.2% and 3.7%, respectively. The mean fluoroscopy time was 49.4 ± 26.6 min (n = 134), and the mean procedure duration was 113.9 ± 31.9 min (n = 133). ConclusionsThis study demonstrates the superiority of HBA compared with ADT for treatment of patients with PAF, and a favorable safety profile.

High‐Volume Lesions Using a New Second‐Generation Open Irrigation Radiofrequency Catheter Are Associated with the Development of Inhomogeneous Lesions

After catheter ablation there is often a discrepancy between acute and chronic success rates. We aimed to evaluate major determinants for lesion quality and understand different manifestations of lesion structures. In a canine thigh muscle model radiofrequency (RF) current was delivered for 60 seconds at 30 W (n = 39) or 50 W (n = 18) with 15-g contact force. A second-generation 12-hole gold open irrigation catheter (SGIT) and a first-generation six-hole platinum-iridium catheter (FGIT; Biotronik, Berlin, Germany) were used. Electrode and tissue temperatures (at the surface and 3.5-mm and 7-mm depth) were recorded and lesion dimensions were measured. Lesions with steam pops were excluded. Histological examination was performed to evaluate homogeneity of the lesions. Inhomogeneity was defined as a visual multiband lesion pattern indicating different histological characteristics. In total 57 lesions were created. Seventeen lesions were excluded (steam pops) and 40 lesions were analyzed. A total number of 11 homogeneous and 29 inhomogeneous lesions were identified. Using the SGIT catheter 16.7% of the lesions was homogeneous and 83.3% inhomogeneous; for FGIT it was 43.8% and 56.2% (P = 0.065), respectively. Homogeneous lesions had lower volumes as compared to inhomogeneous lesions (514.0 ± 198.8 vs 914.8 ± 399.1 mm, P = 0.003). Multiple logistic regression analysis indicated that the SGIT catheter is a significant predictor for inhomogeneous lesions (odds ratio 6.5, 95% confidence interval 1.1-38.8; P = 0.040) independent from power setting and flow rate. The development of inhomogeneous lesions after acute RF ablation is associated with higher lesion volumes and the use of the second-generation irrigation gold-tip catheter.

Energy titration strategies with the endoscopic ablation system: lessons from the high-dose vs. low-dose laser ablation study

To assess the effects of low-dose (LD) and high-dose (HD) ablation on acute and chronic success in patients with atrial fibrillation (AF). While the concept of visually guided pulmonary vein isolation (PVI) has been established little is known on energy titration using laser ablation. In 60 patients with AF, PVI using the endoscopic ablation system (EAS) was performed in two groups. Visually guided ablation was carried out after obtaining optimal tissue contact with 5.5-8.5 W in the LD group and with >8.5 W in the HD group. Acute PVI after a single visually guided circular lesion set was achieved in 89% (HD) and 69% (LD), respectively, (P = 0.0004). In 70 and 39% of patients all PVs were isolated after a single ablation circle in the HD and LD group, respectively, (P = 0.009). After gap ablation all PVs were isolated with the EAS. More energy was deployed (6483 ± 1834 vs. 5306 ± 2258 Ws; P ≤ 0.0001) with less applications (31.6 ± 8 vs. 35.2 ± 15 applications per PV; P = 0.03) leading to shorter procedure times (128 ± 17 vs. 154 ± 38 min; P = 0.001). During median follow-up of 311 days (261-346) recurrence rate was 17 and 40% in the HD and LD group, respectively. In both groups one phrenic nerve palsy was observed. For the first time, it was demonstrated that high ablation power affects acute and chronic outcomes. High-dose laser balloon ablation allows for an acute PVI rate of 89% solely by visually guided circular ablation and is associated with a chronic success rate of 83% after a single procedure.

New techniques for endovascular treatment of peripheral artery disease with focus on chronic critical limb ischemia

Chronic critical limb ischemia (CLI) represents the most advanced stage of peripheral arterial disease. CLI is associated with a high risk for limb loss and revascularization, either by surgical or endovascular means, is absolutely mandatory. With traditional techniques such as balloon angioplasty, limb salvage was reported in 80 to 90%. However, in case of failed revascularization attempt, limb loss was 40 to 50% and mortality approximately 20%. This review summarizes new developments in endovascular techniques which increase the acute and chronic success rate of endovascular procedures and therefore potentially further improve limb salvage rates. Special crossing and re-entry devices designed for femoro-popliteal application may even facilitate recanalization of long chronic occlusions. Improved stent design, atherectomy devices and drug coated balloons improve patency rates and may result in improved wound healing rates. Moreover, downsizing the catheter tools for infrapopliteal artery disease opens new horizons also for the treatment of complex below-the-knee lesions representing an increasing patient population due to the increasing prevalence of diabetes and end-stage renal failure.

Abstract 646: Epicardial Ablation Of Ventricular Tachycardia - A Single Centre Experience

Background: Radiofrequency current ablation (RFA) of ventricular tachycardia (VT) focuses on endocardial (endo) substrates. However, if endo RFA fails, an epi approach is a potential treatment option. We report a single centre experience of epi VT ablation. Patients and Methods: Between 06/2005 and 02/2008 42 pts (14 female, mean age 49 ± 18 years) underwent electroanatomical endo and epi mapping and ablation for intractable VT, syncope or VT storm with multiple ICD discharges. Pts with normal heart (n=7), ischemic cardiomyopathy (ICM; n=8), NICM (n=11), ARVD (n=8), LV-aneurysm (n=7) or sarcoidosis (n=1) were studied. Mean LV ejection fraction was 45±12%. 20/42 had had at least 1 previous ablation attempt for VT (range 1– 4 ablations). Acute success was defined as non-inducibility of the previously inducible VT. Chronic success was defined as recurrence of any VT. Results: Acute procedural success rate was 79% (30/38). In 4 pts VTs were not inducible during EPS. In 28/42 pts endo mapping revealed no pathologic potentials. In 23/38 pts and 7/38 the succesful RFC ablation site was epi and endo, respectively. In 9/38 pts endo ablation failed and VT could only be ablated from epi. Further 7/38 pts needed both endo and epi ablation. In In 4/8 failed ablations epi RFC ablation was impossible due to failed access to target site (adhesions; n=2), close vicinity of a coronary artery (n=1) or the phrenic nerve (n=1). Procedure duration was 263±97 min. Unfortunately, 1 pt died due to perforation of RV and 1 pt had severe hepatic bleeding after epi puncture. One pt died in cardiogenic shock 1 d after the procedure. In 2 pts a sterile pericarditis occurred which resolved without any further intervention. After a median follow-up of 293 days (1–929 days) 53% of pts were alive and free from any VT. Conclusion: In pts with failed endo RFC ablation for VT due to different etiologies epi RFC ablation was acutely successful in 61% of pts with a moderate chronic success rate. However, major complications occured in approximately 5% of pts. Epi mapping should be considered if endo pathologic potentials are absent or if endo ablation failed.

Long term outcome of cavotricuspid isthmus cryoablation for the treatment of common atrial flutter in 180 patients: A single center experience

ObjectiveRecent literature has shown that common type atrial flutter (AFL) can recur late after cavotricuspid isthmus (CTI) catheter ablation using radiofrequency energy (RF). We report the long term outcome of a large group of patients undergoing CTI ablation using cryothermy for AFL in a single center.MethodsPatients with AFL referred for CTI ablation were recruited prospectively from July 2001 to July 2006. Cryoablation was performed using a deflectable, 10.5 F, 6.5 mm tip catheter. CTI block was reassessed 30 min after the last application during isoproterenol infusion. Recurrences were evaluated by 12-lead ECG and 24 h Holter recording every clinic visit (1/3/6/9 and 12 months after the procedure and yearly thereafter) or if symptoms developed.ResultsThe 180 enrolled patients had the following characteristics: 39 women (22%), mean age 58 years, no structural heart disease in 86 patients (48%), mean left atrium diameter 44 ± 7 mm and mean left ventricular ejection fraction 57 ± 7%. The average number of applications per patient was 7 (3 to 20) with a mean temperature and duration of −88°C and 3 min, respectively. Acute success was achieved in 95% (171) of the patients. There were no complications. After a mean follow-up of 27 ± 17 (from 12 to 60) months, the chronic success rate was 91%. The majority of the recurrences occurred within the first year post ablation. One hundred and twenty three patients had a history of atrial fibrillation (AF) prior to CTI ablation and 85 (69%) of those remained having AF after cryoablation. In 20 of 57 (35%) patients without a history of AF prior to CTI ablation, AF occurred during follow-up.ConclusionsThis prospective study showed a 91% chronic success rate (range 12 to 60 months) for cryoablation of the CTI in patients with common type AFL and ratified the frequent association of AF with AFL.

Lengthier cryoablation and a bonus cryoapplication is associated with improved efficacy for cryothermal catheter ablation of supraventricular tachycardias in children

Cryoablation is an effective treatment for children with supraventricular tachycardias (SVT). The present study documents the effect of two different cryoablation protocols on acute and chronic success rates. Fifty-three consecutive patients (age range, 5-20 years) were treated; patients 1 to 17 were treated by a standard ablation protocol and patients 18 to 53 were treated by a modified ablation protocol that required lengthier cryoablations plus delivery of a bonus cryoapplication to consolidate the acutely successful irreversible lesion created at intervention. Electrophysiological study (EPS) was performed with diagnostic catheters and cryoablations were performed with a 7FR 4 mm tip catheter (CryoCath Technologies). Acute endpoints for non-inducibility of atrioventricular nodal re-entrant tachycardia (AVNRT) by programmed atrial stimulation at baseline or during isoproterenol performed 30 min post procedure, as well as non-inducibility and conduction block over the accessory pathway (AP). The chronic endpoint was arrhythmia recurrence post intervention. No permanent cryo-related complications or adverse outcomes were reported. Acute success rates for patients 1 to 17 and 18 to 53 were 88 and 100%, respectively. The cumulative percentage of patients without arrhythmia recurrence at 12 month follow-up was significantly different at 73 and 90%, respectively. Lengthier cryoablation delivery, approximating 7 min per cryoablation, increases the acute success rate at intervention. Moreover, these lengthier cryoablation deliveries plus a bonus cryoapplication to consolidate the acutely successful irreversible lesion created at intervention may also significantly improve the chronic success rate, while also maintaining an excellent safety profile for cryoablation treatment of children with SVT such as AVNRT and AP located near the AV junction.

Long-term efficacy of cryo catheter ablation for the treatment of atrial flutter: Results from a repeat electrophysiologic study

We investigated the long-term efficacy of cryo ablation for treatment of atrial flutter. To our knowledge, no study has assessed the long-term efficacy of cryo ablation by assessing both symptom and conduction recurrence. A total of 45 consecutive patients with symptomatic atrial flutter were ablated with a 7-F, 6-mm-tip, quadripolar cryo catheter (Freezor Xtra, CryoCath Technologies Inc., Kirkland, Canada). Electrophysiologic studies (EPS) were performed with diagnostic catheters. Cryo ablation was at -75 degrees C for 4 min, beginning at the inferior rim of the coronary sinus os and creating a posterior line to the Eustachian ridge. Safety, bi-directional isthmus block at intervention, and recurrence at three, six, and nine months post procedure were assessed. There were no adverse events reported. All patients were free of discomfort on cryo energy delivery. The acute success rate at intervention was 87%. Follow-up data from 39 acutely successful patients showed 27 (69%) without conduction recurrence on repeat EPS at three months, and none (0%) had symptom recurrence documented by Holter monitoring, electrocardiogram, and/or patient diary records at three, six, and nine months follow-up. Our experience with a new 7-F, 6-mm-tip, quadripolar cryo catheter yielded a fairly high success rate at intervention, an excellent safety profile, and a good chronic success rate in terms of symptom recurrence. However, further monitoring is necessary to determine whether all asymptomatic patients continue to remain free of symptoms, given the small pool of patients demonstrated to have conduction recurrence.

Catheter Ablation for the Common Type of Atrial Flutter: Where Do We Stand?

Atrial flutter is a reentrant tachycardia that originates in the right atrium. The wave front of atrial flutter travels craniocaudally along the anterolateral wall of the right atrium, surrounds the inferior vena cava, and crosses the region between this structure and the tricuspid ring before closing the. circuit after upward septal propagation. The area located between the tricuspid annulus and the inferior vena cava has been proposed as an ideal target for ablation because it appears to be an isthmus that is an obligatory route for closing the inferior part of the arrhythmia circuit. Various publications dealing with radiofrequency ablation of this tachycardia have dealt with different approaches, and a wide range of acute and chronic success rates have been reported. The main difficulty in interpreting the results of this series is the lack of a carefully defined patient selection, technique description, and follow‐up protocol. In almost all of these series it clearly appears that a significant number of late flutter recurrences occur in these patients, in addition to the emergence of previously unknown atrial fibrillation. Many recent reports, where ablation has been targeted at the inferior vena cava‐tricuspid annulus isthmus, have shown a high rate of acute, success. In our experience, the procedure seems to be facilitated by the use of extra large tip (8‐mm) ablation catheters that allow the use of higher power outputs. Careful mapping of the ablation site has shown that creation of complete bidirectional block at the isthmus is important for prevention of late recurrences. Further technological improvements should aim at developing energy delivery systems that allow controlled destruction of wide areas of the atrial myocardium. (J Interven Cardiol 1996;9:35–44)

The problem of reocclusion and restenosis — Clinical aspects

Summary Balloon angioplasty is practised world-wide today and has become the treatment of choice for many patients with coronary heart disease. However, its acute success rate is impaired by the phenomenon of reocclusion and its chronic success rate is reduced by the phenomenon of restenosis. Acute coronary occlusion occurs in 4.3 to 8.3% and is associated with a high mortality and myocardial infarction rate. Continuous monitoring of changes in the sum of three dimensional ST- and QRS- vectors is a valuable tool in the detection of reocclusion, which may occur silently. Attempts to manage this situation adequately include resolution of coronary spasm and prolonged dilatation with perfusion balloons. Application of intracoronary stents appear to be not only an effective alternative, but also superior in short and long term. Restenosis, affecting 30–40% of successfully dilated coronary arteries, remains the second major clinical problem; the underlying pathophysiological mechanisms of which are still poorly understood. Many pharmacological and technical attempts to decrease the incidence and extent of restenosis have been made, but in clinical trials none has been proven to be successfully so far.