Impact of pulmonary vein anatomy and ostial dimensions on long-term outcome after single-shot device-guided cryoablation for paroxysmal atrial fibrillation.

BACKGROUND: Cryoballoon (CB)-guided pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). This observational study aimed to assess the role of individual anatomical characteristics to predict long-term freedom from arrhythmia recurrence after CB-guided PVI for paroxysmal AF (PAF). METHODS: Three hundred fifty three consecutive patients (58 ± 11 years, 56% males), undergoing PVI between 2012 and 2018 were analysed. Individual pulmonary vein (PV) anatomy was assessed using preprocedural cardiac magnetic resonance imaging (MRI). For each PV, the cross-sectional area (CSA) was calculated. The impact of PV characteristics and CSA on long-term AF-free survival was evaluated. RESULTS: Acute PVI was achieved in all patients. Two hundred twenty-three patients (63%) had a normal PV anatomy (2 left- and 2 right-sided PV). Variant PV anatomy was present in 130 patients (37%). During the observation period of 48 months, AF-recurrence was documented in 167 patients (47 %). Patients with AF-recurrence presented with significantly enlarged right-sided PVs and left superior PVs (LSPVs) (p < 0.001). The presence of left common PVs (LCPVs) (n = 75, Log-rank p < 0.001) as well as right variant PVs (n = 35, Log rank p < 0.001) was associated with a significantly impaired long-term AF-free survival rate as compared to patients with normal PV characteristics. CONCLUSION: Variant PV anatomy is a good predictor for AF-recurrence. A correlation between an enlarged CSA of right-sided PVs as well as LSPVs and AF-recurrence was documented.

EASY-WPW: a novel ECG-algorithm for easy and reliable localization of manifest accessory pathways in children and adults.

AIMS: Accessory pathway (AP) ablation is a standard procedure for the treatment of Wolff-Parkinson-White syndrome (WPW). Twelve-lead electrocardiogram (ECG)-based delta wave analysis is essential for predicting ablation sites. Previous algorithms have shown to be complex, time-consuming, and unprecise. We aimed to retrospectively develop and prospectively validate a new, simple ECG-based algorithm considering the patients' heart axis allowing for exact localization of APs in patients undergoing ablation for WPW. METHODS AND RESULTS: Our multicentre study included 211 patients undergoing ablation of a single manifest AP due to WPW between 2013 and 2021. The algorithm was developed retrospectively and validated prospectively by comparing its efficacy to two established ones (Pambrun and Arruda). All patients (32 ± 19 years old, 47% female) underwent successful pathway ablation. Prediction of AP-localization was correct in 197 patients (93%) (sensitivity 92%, specificity 99%, PPV 96%, and NPV 99%). Our algorithm was particularly useful in correctly localizing antero-septal/-lateral (sensitivity and specificity 100%) and posteroseptal (sensitivity 98%, specificity 92%) AP in proximity to the tricuspid valve. The accuracy of EASY-WPW was superior compared to the Pambrun (93% vs. 84%, P = 0.003*) and the Arruda algorithm (94% vs. 75%, P < 0.001*). A subgroup analysis of children (n = 58, 12 ± 4 years old, 55% female) revealed superiority to the Arruda algorithm (P < 0.001*). The reproducibility of our algorithm was excellent (Ï°>0.8; P < 0.001*). CONCLUSION: The novel EASY-WPW algorithm provides reliable and accurate pre-interventional ablation site determination in WPW patients. Only two steps are necessary to locate left-sided AP, and three steps to determine right-sided AP.

Posterior wall substrate modification using optimized and contiguous lesions in patients with atrial fibrillation.

BACKGROUND: Radiofrequency (RF) linear ablation at the left atrial (LA) roof and bottom to isolate the LA posterior wall using contiguous and optimized RF lesions was evaluated. Achieving isolation of the LA posterior wall is challenging as two continuous linear lesion sets are necessary. METHODS: Forty consecutive patients with symptomatic atrial fibrillation (AF) and arrhythmia substrates affecting the LA posterior wall underwent posterior wall isolation by linear lesions across the roof and bottom. The cohort was divided into two groups: group 1 (20 patients) linear ablation guided by contact force (CF) only; group 2 (20 patients) guided by ablation index (AI) and interlesion distance. RESULTS: Bidirectional block across the LA roof and bottom was achieved in 40/40 patients. Additional endocardial RF applications in 5 patients from group 1 vs. 3 patients from group 2 resulted in posterior wall isolation in all patients. Procedure duration was almost equal in both groups. CF and AI were significantly higher in group 2 for the roof line, whereas no statistical difference was found for the bottom line. AI-guided LA posterior wall isolation led to a significantly lower maximum temperature increase. The mean AI value as well as the mean value for catheter-to-tissue CF for the roof line were significantly higher when AI-guided ablation was performed. Standard deviation in group 2 showed a remarkably lower dispersion. CONCLUSIONS: Ablation index guided posterior wall isolation for substrate modification is safe and effective. AI guided application of the posterior box lesion allows improved lesion formation.

Long-Term Efficacy and Impact on Mortality of Remote Magnetic Navigation Guided Catheter Ablation of Ventricular Arrhythmias.

Remote magnetic navigation (RMN) facilitates ventricular arrhythmia (VA) ablation. This study aimed to evaluate the long-term efficacy of RMN-guided ablation for ventricular tachycardia (VT) and premature ventricular contractions (PVC). A total of 176 consecutive patients (mean age 53.23 ± 17.55 years, 37% female) underwent VA ablation for PVC (132 patients, 75%) or VT (44 patients, 25%). The cohort consisted of 119 patients (68%) with idiopathic VA, 31 (18%) with ischemic (ICM), and 26 (15%) with dilated cardiomyopathy (DCM). VA recurrence was observed in 69 patients (39%, mean age 51.71 ± 19.91 years, 23% female) during a follow-up period of 5.48 years (first quartile 770.50 days, second quartile 1101.50 days, third quartile 1615.50 days). Left ventricular ejection fraction <40% lead to a significantly increased risk for VA (p = 0.031*). Multivariate analyses found DCM to be an independent predictor (IP) for VA recurrence (p < 0.001*, hazard ratio (HR) 3.74, confidence interval (CI) 1.58-8.88). ICM resulted in a lower increase in VA recurrence (p = 0.221, HR 1.49, CI 0.79-2.81). Class I/III/IV antiarrhythmic drug therapy (AADs) was also identified as IP for recurrence (p = 0.030*, HR 2.48, CI 1.11-5.68). A total of 16 patients (9%) died within the observational period. RMN-guided ablation of VA lead to acceptable long-term results. An impaired LV function, DCM, and AADs were associated with a significant risk for VA recurrence. Personalized paths are needed to improve efficacy and outcome.

Late diagnosed DiGeorge syndrome in a 44-year-old female: a rare cause for recurrent syncopes in adulthood-a case report.

BACKGROUND: DiGeorge syndrome, also known as 'CATCH 22', is the most common deletion in humans and is one of the velocardiofacial syndromes. It is characterized by a specific facial phenotype, and structural and functional abnormalities in the cardiac and endocrine systems. One form of endocrine system dysfunction is hypocalcaemia, which causes arrhythmic events and can result in a transient loss of consciousness. We present a case highlighting the late diagnosis of DiGeorge syndrome in a patient with recurrent episodes of syncope due to suspected arrhythmic events secondary to hypocalcaemia. CASE SUMMARY: A 44-year-old woman was referred for further investigation of recurrent syncope episodes and documented transient QT-prolongation with hypocalcaemia. Previous detailed cardiological examination, including invasive procedures such as coronary angiography and cardiac magnetic resonance tomography, was unremarkable. Slight characteristic facial dysmorphia and transient hypocalcaemia were strongly suggestive of DiGeorge syndrome. The diagnosis was confirmed by genetic testing. Calcium substitution was initiated and no recurrent episodes of syncope or arrhythmic events were reported during 12 months of follow-up. DISCUSSION: Clinical presentation and time of manifestation of the DiGeorge syndrome varies widely depending on the mutation expression extent. An atypical disease course may delay the diagnosis and appropriate management of affected patients. In this case, confirmation of the diagnosis allowed the initiation of appropriate treatment, reducing the risk for further events. Given that syncope and arrhythmia can be the first and only manifestation of late-onset DiGeorge syndrome, specialists in adult cardiology need to be aware of this presentation.

Cool enough? Lessons learned from cryoballoon-guided catheter ablation for atrial fibrillation in young adults.

INTRODUCTION: Cryoballoon (CB)-guided ablation of atrial fibrillation (AF) is established in symptomatic AF patients. This study sought to determine the safety and efficacy of CB pulmonary vein isolation (PVI) in young adults. METHODS AND RESULTS: A total of 93 consecutive patients aged <45 years referred to our center for AF ablation were included in this observational study. All patients received CB-guided PVI according to a standardized institutional protocol. Follow-up was performed in our outpatient clinic using 72-h Holter monitoring and periodic telephone interview. Recurrence was defined as any AF/atrial tachycardia (AT) episode >30 s following a 3-month blanking period. A propensity matched control group consisting of patients older than 45 years were used for further evaluation. Mean age was 35 ± 7 years, 22% suffered from persistent AF, 85% were male. Mean follow-up was 2.6 ± 2 years. At the end of the observational period, 83% of patients were free of any AF/AT episodes. There was an excellent overall 12-month success rate of 92%. In comparison to a matched group the overall recurrence rate was noticeably lower in the young group (15% vs. 27%). Increasing age was associated with a hazard ratio of 1.16 for recurrence. In a multivariate analysis model, left atrial diameter remained as significant predictor of AF/AT recurrence. The complication rate was low, no permanent phrenic nerve palsy was observed. CONCLUSION: CB-guided PVI in young adults is safe and effective with favorable long-term results. It may be considered as first-line therapy in this relatively healthy population.

Novel electroanatomical map for permanent his bundle pacing: the Mont Blanc approach - influence of the learning curve and procedural outcome.

AIMS: Pacing the specific conduction system like the Bundle of His (HB) can lead to more physiologic activation patterns compared to traditional right ventricular apical pacing. The aim of this study was to estimate the feasibility and value of electroanatomical mapping (EAM) for HB pacing during the learning curve and its impact on procedural outcome. METHODS AND RESULTS: Fifteen consecutive patients were treated using EAM of the His bundle region before implantation. Voltage and activation maps of HB potentials were performed. The activation time from His potential to R wave (ECG-reference) was measured and correlated to the HV interval. The atrial and ventricular potentials were blended so the active window could only see the His potential. After completing the activation map, it was transformed into a peak-to-peak voltage map of the HB. With reversed black and white colour scale, the exact point of the maximal His signal amplitude was visualized. Procedural data for the implantation were analysed using this innovative approach. The average total procedural time and fluoroscopy time was 88.2 ± 19.1 min and 10.9 ± 4.5 min, respectively. The 3D mapping time was 18.4 ± 5.1 min. The 13.9 ± 5.1 His potential points were needed in average to complete the map. No periprocedural complications were seen in this cohort. In 86.7% of cases, His bundle pacing was successful. The average threshold for the His bundle stimulation and the R-wave amplitude was 1.62 ± 1 V (@1.0 ms) and 4.8 ± 3.2 mV, respectively. The pacing impedance was 513.5 ± 102.8 Ω. Average paced QRS complex width was 116.9 ± 20.3ms. On average 2.6 ± 1.6 lead positions were targeted to find the optimal pacing site. CONCLUSION: Electroanatomical mapping-guided implantation of His-bundle leads can facilitate the identification of optimal pacing sites and allow to minimize procedure and fluoroscopy times even during the phase of the learning curve.

Catheter ablation of atrial fibrillation in a functionally univentricular heart: a risk-adjusted interventional approach.

In adults with congenital heart disease, atrial fibrillation occurs at a lower age due to the increased atrial stress compared to structurally normal hearts. The ablation target thus results from the underlying heart defect and the specific arrhythmia: in the case of atrial fibrillation, pulmonary vein isolation with left atrial substrate modification can be performed safely and effectively taking into account the individual cardiac lesion, which is often related to difficult transseptal access. This case is a representative example of catheter ablation of atrial fibrillation in a patient with a functional univentricular heart using intracardiac echocardiography-guided double transseptal puncture.

Second generation cryoballoon ablation for persistent atrial fibrillation: an updated meta-analysis.

BACKGROUND: Catheter ablation is an established treatment option for patients with symptomatic atrial fibrillation (AF). The cornerstone of AF ablation is pulmonary vein isolation (PVI). The second-generation cryoballoon (2G-CB) has shown non-inferiority to radiofrequency (RF) ablation in paroxysmal AF in several trials. Growing evidence suggests that 2G-CB is also effective in patients with persistent AF (perAF). The aim of this study was to summarize and analyze available data on safety and mid-term (≥ 12 months) efficacy of PVI using 2G-CB in patients with perAF. METHODS: We did a search in PubMed, Web of Science, Cochrane Library, and clinicaltrials.gov in December 2016 for studies of 2G-CB ablation for perAF. Studies reporting clinical success rates at a follow-up (FU) of ≥ 12 months were included. Success was defined as freedom from any atrial arrhythmia lasting > 30 s after an initial blanking period of 3 months. Acute success and complication rates were also assessed. Data were analyzed applying random-effects model. RESULTS: A total of 917 patients from 11 studies meeting study inclusion criteria were analyzed. After a mean FU of 16.7 ± 3.0 months, 68.9% were free from recurrences [95% confidence interval (CI) 63.4-74.7%]. Overall acute success rate was 99.7% (95% CI 99.2-100%). Complications occurred in 5.5% (95% CI 2.4-9.6%). Vascular access complications were the most frequent 3.3% (95% CI 1.5-5.6%). The rate of phrenic nerve palsy/injury was 2.09% (95% CI 0.8-3.9%). No death, stroke or myocardial infarction was reported. CONCLUSION: The 2G-CB seems to be safe and effective in the treatment of perAF in the mid-term.

Reduction of radiation exposure in cryoballoon ablation procedures: a single-centre study applying intracardiac echocardiography and other radioprotective measures.

AIMS: The population treated with cryoballoon (CB) ablation is relatively young, and radiation protection is of major importance. We aimed to demonstrate that radiation exposure can be markedly reduced by intracardiac echocardiography (ICE) and optimized settings of the X-ray system. METHODS AND RESULTS: We analysed 100 patients undergoing CB pulmonary vein isolation (PVI) for treatment of paroxysmal atrial fibrillation. In 50 consecutive patients (25 male, 59 ± 13 years; Group 1), we used ICE, skipped PV angiography prior to CB inflation, and avoided fluoroscopy whenever possible. Furthermore, we reduced the frame rate, minimized distance between patient and detector, and consequently applied collimation. These patients were compared with 50 similar preceding patients in Group 2 (29 male, 61 ± 12 years). Total fluoroscopy time was reduced from 18 ± 6 min in Group 2 to 12 ± 5 min in Group 1 (P < 0.001). Moreover, the dose area product was significantly lower (1555 ± 1219 vs. 4935 ± 2094 cGycm2, P < 0.001), total freezing time was significantly shortened (1855 ± 399 vs. 2121 ± 756 s, P = 0.031), and contrast media use was significantly reduced (66 ± 25 vs. 109 ± 27 mL, P < 0.001). At the same time, total procedure duration and complication rates did not differ significantly between both groups. After a 12 months follow-up, a similar percentage of patients was free from recurrences (74% in Group 1 vs. 78% in Group 2, P = 0.640). CONCLUSION: Radiation exposure in CB PVI can be markedly reduced without prolonging procedure times, affecting the outcome or complication rates. Moreover, ICE seems to shorten total freezing time.