Kristel Wauters

Phrenic nerve paralysis during cryoballoon ablation for atrial fibrillation: A comparison between the first- and second-generation balloon

BACKGROUND Phrenic nerve palsy (PNP) is the most frequently observed complication during cryoballoon ablation (CB; Arctic Front, Medtronic, MN) occurring in roughly 7%-9% of the cases. The new second-generation cryoballoon ablation Arctic Front Advance (CB-A) (Arctic Front) has recently been launched in the market. OBJECTIVE To evaluate the incidence of right PNP with the new CB-A in comparison with the first-generation balloon in a series of consecutive patients that underwent pulmonary vein isolation with this modality. METHODS The study was designed as an observational study with a prospective follow-up. In total, 121 consecutive patients were included: 80 patients with the CB (group 1) and 41 with the CB-A (group 2). RESULTS Mean procedural times, fluoroscopic times, and time to pulmonary vein isolation documented by real-time recordings were significantly lower in group 2 (P ≤ .05). The occurrence of PNP was significantly higher in group 2 (6.25% [5 of 80] in group 1 vs 19.5% [8 of 41] in group 2; P = .033). At 7 months, PNP persisted in 1 (2.5%) patient in the CB-A group. CONCLUSIONS Right PNP seems to occur in a significantly larger number of patients with the second-generation CB-A. However, this complication is reversible in nearly all cases on short-term follow-up. More refined phrenic nerve monitoring during right-sided pulmonary vein ablation and less vigorous wedging maneuvers in the pulmonary vein ostia might significantly reduce the occurrence of this complication.

Implantable Cardioverter-Defibrillator Therapy in Brugada Syndrome: A 20-Year Single-Center Experience

BACKGROUND Patients with Brugada syndrome and aborted sudden cardiac death or syncope have higher risks for ventricular arrhythmias (VAs) and should undergo implantable cardioverter-defibrillator (ICD) placement. Device-based management of asymptomatic patients is controversial. ICD therapy is associated with high rates of inappropriate shocks and device-related complications. OBJECTIVES The objective of this study was to investigate clinical features, management, and long-term follow-up of ICD therapy in patients with Brugada syndrome. METHODS Patients presenting with spontaneous or drug-induced Brugada type 1 electrocardiographic findings, who underwent ICD implantation and continuous follow-up at a single institution, were eligible for this study. RESULTS A total of 176 consecutive patients were included. During a mean follow-up period of 83.8 ± 57.3 months, spontaneous sustained VAs occurred in 30 patients (17%). Eight patients (4.5%) died. Appropriate ICD shocks occurred in 28 patients (15.9%), and 33 patients (18.7%) had inappropriate shocks. Electrical storm occurred in 4 subjects (2.3%). Twenty-eight patients (15.9%) experienced device-related complications. In multivariate Cox regression analysis, aborted sudden cardiac death and VA inducibility on electrophysiologic studies were independent predictors of appropriate shock occurrence. CONCLUSIONS ICD therapy was an effective strategy in Brugada syndrome, treating potentially lethal arrhythmias in 17% of patients during long-term follow-up. Appropriate shocks were significantly associated with the presence of aborted sudden cardiac death but also occurred in 13% of asymptomatic patients. Risk stratification by electrophysiologic study may identify asymptomatic patients at risk for arrhythmic events and could be helpful in investigating syncope not related to VAs. ICD placement is frequently associated with device-related complications, and rates of inappropriate shocks remain high regardless of careful device programming.

Prognostic Value of Programmed Electrical Stimulation in Brugada Syndrome 20 Years Experience

Background—The prognostic value of electrophysiological investigations in individuals with Brugada syndrome remains controversial. Different groups have published contradictory data. Long-term follow-up is needed to clarify this issue. Methods and Results—Patients presenting with spontaneous or drug-induced Brugada type I ECG and in whom programmed electric stimulation was performed at our institution were considered eligible for this study. A total of 403 consecutive patients (235 males, 58.2%; mean age, 43.2±16.2 years) were included. Ventricular arrhythmias during programmed electric stimulation were induced in 73 (18.1%) patients. After a mean follow-up time of 74.3±57.3 months (median 57.3), 25 arrhythmic events occurred (16 in the inducible group and 9 in the noninducible). Ventricular arrhythmias inducibility presented a hazard ratio for events of 8.3 (95% confidence interval, 3.6–19.4), P<0.01. Conclusions—Programmed ventricular stimulation of the heart is a good predictor of outcome in individuals with Brugada syndrome. It might be of special value to guide further management when performed in asymptomatic individuals. The overall accuracy of the test makes it a suitable screening tool to reassure noninducible asymptomatic individuals

Asymptomatic Brugada Syndrome: Clinical Characterization and Long Term Prognosis

Background—Among Brugada syndrome patients, asymptomatic individuals are considered to be at the lowest risk. Nevertheless, arrhythmic events and sudden cardiac death are not negligible. Literature focused on this specific group of patients is sparse. The purpose of this study is to investigate the clinical characteristics, management, and long-term prognosis of asymptomatic Brugada syndrome patients. Methods and Results—Patients presenting with spontaneous or drug-induced Brugada type I ECG and no symptoms at our institution were considered eligible. A total of 363 consecutive patients (200 men, 55.1%; mean age, 40.9±17.2 years; 41 [11.3%] with spontaneous type I ECG) were included. Electrophysiological study was performed in 321 (88.4%) patients, and ventricular arrhythmias were induced in 32 (10%) patients. An implantable cardioverter defibrillator was implanted in 61 (16.8%) patients. After a mean follow-up time of 73.2±58.9 months, 9 arrhythmic events occurred, accounting for an annual incidence rate of 0.5%. Event-free survival was 99.0% at 1 year, 96.2% at 5 years, and 95.4% at 10 and 15 years. Univariate analysis identified as risk factors: electrophysiological study inducibility (hazard ratio, 11.4; P<0.01), spontaneous type I (hazard ratio, 4.0; P=0.04), and previous sinus node dysfunction (hazard ratio, 8.0; 95% confidence interval, 1.0–63.9; P=0.05). At the multivariate analysis, only inducibility remained significant (hazard ratio, 9.1; P<0.01) Conclusions—Arrhythmic events in asymptomatic Brugada syndrome patients are not insignificant. Ventricular arrhythmia inducibility, spontaneous type I ECG, and presence of sinus node dysfunction might be considered as risk factors and used to drive long-term management.

On the Quest for the Best Freeze: Predictors of Late Pulmonary Vein Reconnections After Second-Generation Cryoballoon Ablation.

Background—The second-generation cryoballoon is effective in achieving acute pulmonary vein isolation (PVI) and favorable clinical outcome. To date, no data are available on factors affecting late PV reconnection after second-generation cryoballoon ablation. Methods and Results—A total of 29 consecutive patients (25 male, 86.2%; mean age 57.8±13.8 years) underwent a repeat procedure, after a mean 11.6±4.5 months (range, 3.5–19.7 months), after index ablation using the 28-mm second-generation cryoballoon. All repeat ablations were performed using a 3-dimensional electroanatomical mapping system. Among all 115 PVs, including 1 left common ostiums (LCOs), 25 (21.7%) showed a PV reconnection in 20 patients (1.25 per patient). Persistent PVI could be documented in 90 of 115 PVs (78.2%). In 9 of 29 patients (31%), all PVs were electrically isolated. In the multivariable analysis, time to PVI (P=0.03) and failure to achieve −40°C within 60 s (P=0.05) independently predicted late PV reconnection. At receiver-operator curve analysis, time to PVI <60 s identified the absence of PV reconduction (sensitivity, 86.7%; specificity, 86.2%; positive predictive value, 59.1%; and negative predictive value, 96.4%; area under the curve, 0.85; confidence interval, 0.73–0.97; P<0.001). Conclusions—The rate of late PV reconnection after second-generation cryoballoon ablation is low (1.25 PVs/patient). Faster time to isolation and achievement of −40°C within 60 s independently predict durable PVI. In addition, 60-s cut-off for time to PVI indicates persistent isolation with 96.4% negative predictive value. These parameters might guide the operator whether to perform further applications to ensure a long-lasting PVI.

Incidence and characteristics of complications in the setting of second-generation cryoballoon ablation: A large single-center study of 500 consecutive patients

BACKGROUND The second-generation cryoballoon Advance (CB-A) recently launched on the market has technical modifications designed to significantly improve procedural outcome with respect to the first-generation device. OBJECTIVE The purpose of this study was to evaluate the overall incidence of complications in a large sample of patients having undergone pulmonary vein (PV) isolation with CB-A technology. METHODS All consecutive patients who underwent PV isolation procedures using CB-A technology between June 2012 and February 2015 were considered. Exclusion criteria were presence of an intracavitary thrombus, uncontrolled heart failure, moderate or severe valvular disease, left atrial diameter ≥55 mm, and contraindications to general anesthesia. RESULTS During the study period, 500 consecutive patients (67% male, age 57.6 ± 12.9 years) were enrolled. Major complications occurred in 10 patients (2.0%): vascular complications at the puncture site in 6 (1.2%), and thromboembolic events, cardiac tamponade, persisting phrenic nerve palsy, and retroperitoneal hematoma all occurred in a single patient respectively (0.2%). Phrenic nerve palsy occurred in 36 patients (7.2%) and did not revert in only 1 patient at final follow-up of 20 months. No deaths related to the procedure occurred. No predictors of major complication were found. CONCLUSION The present findings highlight that PV isolation using CB-A technology can be safely performed with a low incidence of adverse events. The incidence of major complications after atrial fibrillation ablation procedures using CB-A technology was 2% in our study. The most frequent complication consisted of vascular complications at the puncture site. No deaths related to the procedure occurred.

Prevalence, Clinical Characteristics and Management of Atrial Fibrillation in Patients With Brugada Syndrome

Atrial fibrillation (AF) can be the first manifestation of latent Brugada syndrome (BS). The aim of our study was to assess the prevalence of AF as the first clinical diagnosis in patients with BS and their demographic and clinical characteristics and diagnosis management in a large cohort of patients. The patient group consisted of 611 patients with BS. The data from those with a diagnosis of AF previous to the identification of BS were analyzed (n = 35). Eleven cases were unmasked after the initiation of a class I antiarrhythmic drug and one during the establishment of general anesthesia. In the remaining population, BS was diagnosed using an ajmaline test performed mainly because of younger age in patients with lone AF (n = 13), previous syncope or sudden cardiac death (n = 3), or a clinical history of sudden cardiac death in the family (n = 5). The mean patient age was 49 ± 15 years, 21 were male patients, 14 had a family history of sudden death, 15 had had previous syncope, and 4 had survived cardiac arrest. Concomitant electrical disorder was found in 13 patients. Remarkably, 21 patients had normal findings on the baseline electrocardiogram. In conclusion, AF could be one of the first clinical manifestations of latent BS in a considerable number of patients. This identification is crucial because the treatment of these patients is subject to relevant changes. The ajmaline test plays an essential role, mainly in young patients with a family history of sudden death, despite having normal findings on a baseline electrocardiogram.

Clinical characterisation and long-term prognosis of women with Brugada syndrome.

Objectives Brugada syndrome (BS) in women is considered an infrequent condition with a more favourable prognosis than in men. Nevertheless, arrhythmic events and sudden cardiac death (SCD) also occur in this population. Long-term follow-up data of this group are sparse. The purpose of the present study was to investigate the clinical characteristics and long-term prognosis of women with BS. Methods A consecutive cohort of 228 women presenting with spontaneous or drug-induced Brugada type I ECG at our institution were included and compared with 314 men with the same diagnosis. Results Mean age was 41.5±17.3 years. Clinical presentation was SCD in 6 (2.6%), syncope in 51 (22.4%) and the remaining 171 (75.0%) were asymptomatic. As compared with men, spontaneous type I ECG was less common (7.9% vs 23.2%, p<0.01) and less ventricular arrhythmias were induced during programmed electrical stimulation (5.5% vs 22.3%, p<0.01). An implantable cardioverter defibrillator (ICD) was implanted in 64 women (28.1%). During a mean follow-up of 73.2±56.2 months, seven patients developed arrhythmic events, constituting an event rate of 0.7% per year (as compared with 1.9% per year in men, p=0.02). Presentation as SCD or sinus node dysfunction (SND) was risk factor significantly associated with arrhythmic events (hazard risk (HR) 25.4 and 9.1). Conclusion BS is common in women, representing 42% of patients in our database. Clinical presentation is less severe than men, with more asymptomatic status and less spontaneous type I ECG and prognosis is more favourable, with an event rate of 0.7% year. However, women with SCD or previous SND are at higher risk of arrhythmic events.

Pulmonary vein isolation in patients with Brugada syndrome and atrial fibrillation: a 2-year follow-up.

AIMS Pharmacological treatment of atrial fibrillation (AF) in the setting of Brugada syndrome (BS) might be challenging as many antiarrhythmic drugs (AADs) with sodium channel blocking properties might expose the patients to the development of ventricular arrhythmias. Moreover, patients with BS and implantable cardioverter-defibrillator (ICD) might experience inappropriate shocks because of AF with rapid ventricular response. The role of pulmonary vein isolation (PVI) in patients with BS and recurrent episodes of AF has not been established yet. In this study, we analysed the outcome of PVI using radiofrequency energy or cryoballoon (CB) ablation at 2 years follow-up. METHODS AND RESULTS Consecutive patients with BS having undergone PVI for drug-resistant paroxysmal AF were eligible for this study. Nine patients (three males; mean age: 52 ± 26 years) were included. Six patients (67%) had an ICD implanted of whom three had inappropriate shocks because of rapid AF. At a mean 22.1 ± 6.4 months follow-up, six patients (67%) were free of AF without AADs. None of the three patients who had experienced inappropriate ICD interventions for AF had further ICD shocks after ablation. CONCLUSION In our study PVI can be an effective and safe procedure to treat patients with BS and recurrent episodes of paroxysmal AF.

P-wave indices as predictors of atrial fibrillation recurrence after pulmonary vein isolation in normal left atrial size.

Aims Prolonged P-wave duration and dispersion are universally accepted noninvasive markers for atrial electrical remodeling. Our aim was to analyze P-wave indices as predictors of atrial fibrillation recurrence after pulmonary vein isolation in patients with normal left atrial size. Methods From January 2008 to December 2011, 426 patients with drug-resistant symptomatic paroxysmal atrial fibrillation underwent pulmonary vein isolation as an index procedure by conventional radiofrequency or cryoballoon ablation in our center. Patients with left atrial dilatation, poor-quality electrocardiograms, atrial pacemaker stimulation, and those undergoing repeat procedures were excluded. A total of 201 patients were analyzed during a mean follow-up of 22 ± 16 months. Results Patients with prolonged P-wave duration had higher rates of atrial fibrillation recurrences compared with those without prolonged P-wave duration (49 vs. 14%; P < 0.001). Atrial fibrillation recurrence was significantly associated with prolonged P-wave duration (129 ± 13 vs. 119 ± 11 ms; P < 0.001) and P-wave dispersion (54 ± 12 vs. 42 ± 10 ms; P < 0.001) compared with those who remained in sinus rhythm. P-wave duration and dispersion were independently associated with atrial fibrillation recurrence (hazard ratio 1.045, 95% confidence interval 1.027–1.063, P < 0.001; and hazard ratio 1.049, 95% confidence interval 1.022–1.078, P < 0.001, respectively), after adjusting for left atrial size and age. Conclusion Prolonged P-wave duration and dispersion were found to be independently associated with higher recurrence rates of atrial fibrillation after pulmonary vein isolation in patients with normal left atrial dimension. Therefore, a prolongation of P-wave indices may help to identify those patients in whom electrical remodeling has already occurred and a more extensive ablation may be indicated.