LEFT FREE WALL-SIDED MAHAIM TYPE FIBER AND AV NODAL REENTRY TACHYCARDIA -- UNUSUAL BUT NOT IMPOSSIBLE COMBINATION

A 52-year-old patient with previous catheter ablation of AV nodal reentrant tachycardia (AVNRT) had a redo procedure for reported recurrence. During the study AVNRT was not inducible, but a previously unrecognized left-sided Mahaim type accessory pathway was diagnosed and ablated successfully.

How effective is laparoscopic redo-antireflux surgery?

Summary Background: The failure-rate after primary antireflux surgery ranges from 3 to 30%. Reasons for failures are multifactorial. The aim of this study is to gain insight into the complex reasons for, and management of, failure after antireflux surgery. Methods: Patients were selected for redo-surgery after a diagnostic workup consisting of history and physical examination, upper gastrointestinal endoscopy, quality-of-life assessment, screening for somatoform disorders, esophageal manometry, 24-hour-pH-impedance monitoring, and selective radiographic studies such as Barium-sandwich for esophageal passage and delayed gastric emptying. Perioperative and follow-up data were compiled between 2004 and 2017. Results: In total, 578 datasets were analyzed. The patient cohort undergoing a first redo-procedure (n = 401) consisted of 36 patients after in-house primary LF and 365 external referrals (mean age: 62.1 years [25–87]; mean BMI 26 [20–34]). The majority of patients underwent a repeated total or partial laparoscopic fundoplication. Major reasons for failure were migration and insufficient mobilization during the primary operation. With each increasing number of required redo-operations, the complexity of the redo-procedure itself increased, follow-up quality-of-life decreased (GIQLI: 106; 101; and 100), and complication rate increased (intraoperative: 6,4–10%; postoperative: 4,5–19%/first to third redo). After three redo-operations, resections were frequently necessary (morbidity: 42%). Conclusions: Providing a careful patient selection, primary redo-antireflux procedures have proven to be highly successful. It is often the final chance for a satisfying result may be achieved upon performing a second redo-procedure. A third revision may solve critical problems, such as severe pain and/or inadequate nutritional intake. When resection is required, quality of life cannot be entirely normalized.

Cryoballoon versus radiofrequency guided by ablation index for atrial fibrillation ablation: a retrospective propensity-matched study

Background/Introduction Radiofrequency (RF) and cryoballoon (CB) ablation are established techniques for the treatment of atrial fibrillation (AF). Randomized trials comparing both techniques show similar levels of success; however, studies comparing CB with RF guided by ablation index (AI) are lacking. Purpose To compare the treatment success of CB with RF guided by AI, in patients with paroxysmal or persistent AF undergoing their first ablation procedure. Methods Patients undergoing AF ablation between 2017 and 2019 were retrospectively analysed. Primary success outcome was freedom from recurrence (defined as any episode of AF, atrial flutter or atrial tachycardia lasting >30 seconds and occurring after 91 days from ablation, or need for antiarrhythmic drugs (AAD), cardioversion or redo procedure). Secondary end-point was a composite of adverse cardiovascular outcomes (stroke/TIA, emergency room visit for AF, hospitalization for AF or cardiovascular death). Analysis was done before and after propensity score matching. Results A total of 316 patients were included. Mean age was 56.9±11.7 years. Sixty-two percent were male (n=196). Paroxysmal AF was present in 80.7% (n=255), with no difference between groups. RF was used in 57.9% (n=183) and CB in 42.1% (n=133), with isolation of all pulmonary veins accomplished in 95.9% (n=302), without differences between groups. Mean CHA2DS2-VASc score was 1.5±1.3, being higher in the RF group (1.7±1.3 vs 1.2±1.1; p=0.03); these patients were also older (mean age 58.1±12.0 vs. 55.17±11.0 years; p=0.007) and more likely to be in AF at the ablation (26.7% vs. 16.5%; p=0.006), have chronic kidney disease (40.2% vs. 23.2%; p=0.002), anaemia (11.8% vs. 2.7%; p<0.001), moderate/severe mitral disease (17.5% vs. 7.4%; p=0.012) or history of atrial flutter (17.7% vs. 3.1%; p<0.001). Patients in the CB group had a longer history of AF (3.8±3.5 vs. 3.0±2.9 years; p=0.041), received treatment with AAD more often (60.9% vs. 55.9%; p=0.049) and had longer follow-up time (889±397 vs. 601±239 days; p<0.001). Mean freedom from recurrence was not significantly different between groups (1106 days for CB vs. 889 days for RF; p=0.793), and recurrence rates were also similar (27.8% for CB vs. 23.5% for RF; p=0.291); however, patients treated with CB were more likely to need a redo procedure (38.3% vs. 17.4%; p=0.025). There were no differences in the composite of adverse cardiovascular events or in individual outcomes. Propensity score matching was done, and 154 patients were matched 1:1 for each treatment group. Survival free from recurrence showed no differences (1060 days for CB vs. 864 days for RF; p=0.912), and neither did the recurrence rate. CB patients with recurrence were still more likely to need a redo procedure (37.9% vs. 11.1%; p=0.021). Conclusion RF and CB result in similar survival free from AF and AF recurrence; however, recurrence in CB seems more significant, leading to higher rates of redo procedures. FUNDunding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Centro Hospitalar de Vila Nova de Gaia/Espinho

Cryoablation vs. radiofrequency ablation of the atrioventricular node in patients with His-bundle pacing

Aims Radiofrequency ablation (RFA) of the atrioventricular node (AVN) with His-bundle pacing (HBP) can cause rise in capture thresholds. Cryoablation (CRYO) may offer reversibility in case of threshold rise but has never been tested for AVN ablation in this setting. Our aim was to compare procedural characteristics and outcome of CRYO compared with RFA for AVN ablation in patients with HBP. Methods and results Forty-four patients with HBP underwent AVN ablation for an ‘ablate and pace’ indication. Cryoablation was performed in the first 22 patients and RFA in the following 22 patients. Procedural characteristics, success rates, and change in His capture thresholds were compared between groups. Distance from the ablation site to the His lead was measured using biplane fluoroscopy. Acute success was 100% with both strategies. Median procedural duration was significantly longer for CRYO {50 [interquartile range (IQR) 38–63] min} compared with RFA [36 (IQR, 30–41) min; P = 0.027]. An acute threshold rise of ≥1 V was observed in four CRYO (one complete loss of capture) and three RFA patients (P = 0.38), with all of the applications being within 6 mm of the His lead tip. During follow-up, nine patients had AVN re-conduction (six CRYO vs. three RFA; P = 0.58), but only four patients required a redo procedure (all CRYO; P = 0.09). Conclusion Cryoablation does not offer any advantage over RFA for AVN ablation in patients with HBP and tended to require more redo procedures. If possible, a distance of ≥6 mm should be maintained from the His lead tip to avoid a rise in capture thresholds.

Atrial fibrillation ablation in athletes: 5-years experience of a single italian third-level center

Background The number of master athletes is increasing and treatment of AF is mandatory for sports continuation. However, few data exist about the effectiveness of catheter ablation (CA) in athletes and the feasibility of resuming vigorous exercise afterwards. Objectives Aim of our study was to analyze the efficacy and safety of AF CA in athletes and to evaluate the feasibility of resuming vigorous exercise. Methods We report a retrospective registry of athletes referred to our center for AF CA in the last five years. All athletes were previously declared non-eligible to competitive sport because of recurrences of AF or evidence of persistent asymptomatic AF. CA was performed as per practice and recurrences were defined as recrudescence of symptoms and/or any documentation of AF lasting more than 30 sec. At the end of the follow-up all pts were asked about resuming sport. Results We ablated 40 athletes (38 males, 95%) with a mean age of 48±13 years. Mean left atrium volume was 36±11 ml/m2 and mean ejection fraction was 61±5%. Distribution between AF characteristics was: 31 (78%) paroxysmal AF, 8 (20%) early-persistent AF, 1 (2%) long-persistent AF. After a median follow-up of 787 days, 62,5% of athletes were free from recurrences after one CA procedure and mostly without antiarrhythmic drugs (87%). 7 athletes underwent a redo procedure and all of them were then free of recurrences with an overall freedom from recurrences of 84%. No major complication was observed. Athletes practicing endurance sports showed a negative trend in terms of recurrences (p = ns). Most (72%) of the athletes resumed vigorous exercise after at least 3 months from the CA as per Italian sport protocols. Conclusions CA is safe and efficient in treating AF also in athletes. Resuming high intensity sports is often possible after 3 months from CA. Funding Acknowledgement Type of funding source: None

Radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique: 4-year follow-up

Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation. Cryoablation has been shown to be a safe and effective technique for pulmonary vein isolation. However, there is a significant arrhythmia recurrence rate after cryoablation procedures and there are no established strategies for redo procedures in these patients. Therefore, we have summarized our experience with radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique (including an analysis of pulmonary vein conduction recovery patterns ater procedures performed with the first or second generation cryoballoon). Methods One hundred and fifty patients (paroxysmal AF: 99 patients, persistent AF: 51 patients) had to undergo a redo procedure after initially successful circumferential PV isolation with the cryoballoon technique (Arctic Front Balloon: 75 patients (group A); Arctic Front Advance: 75 patients (group B)). The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy (CARTO) depending on the intra-procedural findings. Results During the redo procedure, a mean number of 1.7 re-conducting PVs were detected (using a circular mapping catheter; group A: 2.1 re-conducting PVs, group B: 1.3 re-conducting PVs). There was a slightly higher incidence of chronic PV reconnections related to the left-sided PV ostia than to the right-sided PVs in both groups. Furthermore, sites of chronic PV reconnection were found more frequently in the inferior parts of the PV ostia than in the superior parts. In 65 patients in group A, a segmental approach was sufficient to eliminate the residual PV conduction because there were only a few recovered PV fibers (1–3 reconnected PVs; group A1). In the remaining 10 patients in group A, a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction of all four pulmonary veins (group A2). In group B, a segmental approach was sufficient in all patients because there was only a minor reconnection of 1–2 PVs. All recovered PVs could be isolated sucessfully again. At 48-month follow-up, 74.7% of all patients were free from an arrhythmia recurrence (112/150 patients; group A: 51/75 patients (68%), group B: 61/75 patients (81.3%)). There were no major complications in both groups. Conclusions In patients with an initial circumferential PVI using the cryoballoon technique, a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation. In most cases only a few re-conducting PV fibers were found and therefore, a segmental re-ablation approach seems to be sufficient in the majority of patients (especially in patients treated with the second generation cryoballoon). Funding Acknowledgement Type of funding source: None

304Cryoablation versus Radiofrequency Ablation of the Atrioventricular Node in Patients with His-bundle Pacing

Background Atrioventricular node (AVN) ablation in the setting of His bundle pacing (HBP) may be challenging due to risk of compromising the function of the His lead. Cryoablation (CRYO) may offer theoretical advantages over conventional radiofrequency ablation (RFA), due to absence of shunting of current to the His lead, more discrete lesions, and potential reversibility in case of transient elevation of capture thresholds. However, CRYO has never been tested for AVN ablation in this setting. Purpose To compare procedural characteristics and outcome of CRYO compared to RFA for AVN ablation in patients with HBP. Methods Thirty-five patients (age 76 ± 8 yrs, 23% male) with HBP underwent AVN ablation for an "ablate and pace" indication. CRYO was performed in the first 22 pts and RFA in the following 13 pts. Procedure and fluoroscopy times, change in His threshold and success rates were compared between groups. Results The acute procedural success rate was 100% for both strategies without any major complications. There were no significant differences in procedure characteristics and outcome between CRYO and RFA, except for significantly shorter application times with RFA and a trend to more frequent reconduction and requirement for a redo procedure with CRYO (see table). All recurrences occurred within one month after ablation. Conclusion CRYO does not seem to offer any advantage over RFA for AVN ablation in patients with HBP, and does not avoid rise of His capture thresholds. Moreover, the recurrence rate may be higher with CRYO leading to more redo procedures. Table Parameter CRYO (22 pts) RFA (13 pts) P-value Total procedure time (min) 50 [38 - 63] 40 [33 - 53] 0.257 Fluoroscopy time (min) 5.0 [2.2 - 5.4] 3.5 [1.9 - 9.0] 0.578 Expo Rx (mcGy.cm2) 237 [110 - 525] 139 [65 - 721] 0.468 Number of applications (n) 6 [3 - 11] 4 [1 - 15] 0.371 Total application time (min) 17 [9 - 29] 3 [1 - 9] 0.001 His threshold pre-ablation (V) 1.63 [0.75 - 3.44] 0.75 [0.53 - 1.63] 0.180 His threshold post-ablation (V) 1.88 [0.75 - 3.81]* 1.25 [0.63 - 3.50] 0.389 His threshold change (V) 0.00 [0.00 - 0.31]* 0.00 [0.00 - 0.75] 0.933 His threshold rise ≥1 volt (n) 4 (18%)* 3 (23%) 0.726 Acute procedural success (n) 22 (100%) 13 (100%) 1.000 AV reconduction during follow-up (n) 5 (23%) 1 (8%) 0.254 AV reconduction needing redo procedure (n) 3 (14%) 0 0.146 Interquartile range is shown in square brackets. *one loss of capture.

P1382Extended long-term follow-up of radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique (first versus second generation cryoballoon)

Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation. Cryoablation has been shown to be a safe and effective technique for pulmonary vein isolation. However, there is a significant arrhythmia recurrence rate after cryoablation procedures and there are no established strategies for redo procedures in these patients. Therefore, we have summarized our experience with radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique (including an analysis of pulmonary vein conduction recovery patterns ater procedures performed with the first or second generation cryoballoon). Methods One hundred and twenty patients (paroxysmal AF: 78 patients, persistent AF: 42 patients) had to undergo a redo procedure after initially successful circumferential PV isolation with the cryoballoon technique. The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy depending on the intra-procedural findings. Results During the redo procedure, a mean number of 1.8 re-conducting PVs were detected (using a circular mapping catheter; group A: 2.1 re-conducting PVs, group B: 1.5 re-conducting PVs). There was a slightly higher incidence of chronic PV reconnections related to the left-sided PV ostia than to the right-sided PVs in both groups. Furthermore, sites of chronic PV reconnection were found more frequently in the inferior parts of the PV ostia than in the superior parts. In 53 patients in group A, a segmental approach was sufficient to eliminate the residual PV conduction because there were only a few recovered PV fibers (1-3 reconnected PVs; group A1). In the remaining 7 patients in group A, a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction of all four pulmonary veins (group A2). In group B, a segmental approach was sufficient in all patients because there was only a minor reconnection of 1-2 PVs. All recovered PVs could be isolated sucessfully again. At 42-month follow-up, 78 % of all patients were free from an arrhythmia recurrence (94/120 patients; group A: 43/60 patients (71 %), group B: 51/60 patients (85 %)). There were no major complications in both groups. Conclusions In patients with an initial circumferential PVI using the cryoballoon technique, a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation. In most cases only a few re-conducting PV fibers were found and therefore, a segmental re-ablation approach seems to be sufficient in the majority of patients (especially in patients treated with the second generation cryoballoon).