Cardioneuroablation for neurally-mediated syncope: Initial experience.

Cardioneuroablation is an emerging alternative therapeutic modality for young patients with severe neurally-mediated syncope. We present two images of cardioneuroablation performed in young patients who suffered from recurrent neurally-mediated syncope with asystole and functional atrioventricular block. The patients remain syncope-free during follow-ups.

Radiofrequency versus cryoballoon catheter ablation in patients with persistent atrial fibrillation: A randomized trial.

INTRODUCTION: Patients with persistent atrial fibrillation (AF) represent a challenging population for rhythm control therapies. Catheter ablation (CA) with pulmonary vein isolation (PVI) is an effective treatment option for the reduction of the arrhythmic burden. Data regarding the comparability between radiofrequency (RF) and cryoballoon ablation (CRYO) in persistent AF are limited. METHODS: This is a prospective, randomized, single-center study designed to compare the efficacy in terms of rhythm control between RF and CRYO in persistent AF. Eligible participants were randomized 2:1 in two arms: RF and CRYO. The primary endpoint of the study was arrhythmia relapse in the early postprocedural period (first 3 months) and in the middle term follow-up (3 months to 12 months). Secondary endpoints included procedure duration, fluoroscopy time, and complications. RESULTS: A total of 199 patients participated in the study (133 patients in the RF arm, 66 in the CRYO arm). No statistically significant difference occurred between the two groups regarding the primary endpoint (recurrences ≤3 months: 35.5% RF vs. 37.9% CRYO, p .755, recurrences >3 months: 26.3% RF vs. 27.3% CRYO, p .999). From the secondary endpoints, CRYO was a procedure of significantly shorter duration (75.15 ± 17.21 in CRYO vs. 136.6 ± 43.33 in RF group, p < .05). CONCLUSION: CRYO and RF ablation appear to be equally effective for rhythm control in patients with persistent AF. CRYO ablation is advantageous in terms of procedure duration.

Diagnostic and therapeutic dilemmas in a patient with myocarditis, Brugada syndrome and arrhythmic syncope.

We present a case of a previously healthy 23-year-old male who presented with chest pain, palpitations and spontaneous type 1 Brugada electrocardiographic (ECG) pattern. Positive family history for sudden cardiac death (SCD) was remarkable. Initially, clinical symptoms in combination with myocardial enzymes elevation, regional myocardial oedema with late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) and inflammatory lymphocytoid-cell infiltrates in the endomyocardial biopsy (EMB) suggested the diagnosis of a myocarditis-induced Brugada phenocopy (BrP). Under immunosuppressive therapy with methylprednisolone and azathioprine, a complete remission of both symptoms and biomarkers was accomplished. However, the Brugada pattern did not resolve. The eventually spontaneous Brugada pattern type 1 established the diagnosis of Brugada syndrome (BrS). Due to his previous history of syncope, the patient was offered an ICD that he declined. After his discharge he experienced a new episode of arrhythmic syncope. He was readmitted and received an ICD.

Contrast-induced early repolarization pattern and ventricular fibrillation.

Malignant arrhythmias during coronary angiography consist a complication of the procedure. Clinicians should be aware that intracoronary infusion of contrast medium can lead to physiological changes that lower the ventricular fibrillation threshold.

Predictors of Adverse Outcomes in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy: A Meta-Analysis of Observational Studies.

Arrhythmogenic cardiomyopathy (AC) is a hereditary disorder characterized by degeneration of cardiac myocytes and their subsequent replacement by fat and fibrous tissue primarily in the right ventricle. Our study aimed to systematically evaluate the impact of significant demographic, clinical, electrocardiographic, and echocardiographic factors in arrhythmic events in AC patients. MEDLINE and Cochrane library databases were manually searched without year or language restriction or any other limits until July 31, 2017. A pooled odds ratio with 95% confidence intervals was calculated for each of the risk factors. Our search retrieved 26 studies (n = 2680 patients, mean age: 37.9 years old, males: 51.9%) which were included in the quantitative synthesis. The most reliable predicting factors/parameters are the following: (1) male gender, (2) presyncope, (3) left ventricular dysfunction, (4) T-wave inversions in inferior leads, (5) proband status, (6) late potentials, (7) syncope, (8) inducibility at electrophysiological study, (9) right ventricular dysfunction, (10) epsilon waves, and (11) premature ventricular contractions greater than 1000/24 h. On the contrary, family history of sudden cardiac death, palpitations, premature ventricular contractions greater than 500/24 h, and T-wave inversions in right precordial leads fail to determine the outcome in this meta-analysis. In conclusion, multiple risk factors have been associated with arrhythmic events in AC patients. However, larger studies are needed to discriminate those patients who will benefit from implantable cardioverter defibrillators.

Adenosine-guided radiofrequency catheter ablation of atrial fibrillation: A meta-analysis of randomized control trials.

BACKGROUND: The prognostic significance of adenosine-mediated dormant pulmonary vein conduction, and whether such dormant conduction should be eliminated, remains controversial. We sought to perform a meta-analysis of data from eligible studies to delineate the prognostic impact of adenosine-guided radiofrequency catheter ablation of atrial fibrillation. METHODS: A systematic literature search was performed using online databases in order to identify relevant studies from January 2004 to September 2016. Ten studies [six observational and four randomized control trials (RCTs)] were included in the analysis. RESULTS: Five studies (two observational and three RCTs) compared the efficacy of adenosine-mediated elimination of dormant conduction versus no adenosine test. Overall, the adenosine-guided ablation strategy displayed better long-term outcomes as compared with no adenosine testing (RR 1.08, 95% CI 1.01-1.14, p=0.02; Heterogeneity: I2=42%, p: 0.14). The meta-analysis of only RCTs failed to show any differences between the two strategies (RR 1.03, 95% CI 0.96-1.11, p=0.37; Heterogeneity: I2 0%, p: 0.41). Eight studies (five observational and three RCTs) addressed the efficacy of adenosine-induced dormant conduction and additional ablation versus no dormant conduction during adenosine challenge. Overall, a trend towards a better outcome in those without dormant conduction during drug challenge was noted (RR 0.89, 95% CI 0.77-1.03, p=0.11; Heterogeneity: I2 65% p: 0.006). The pooled analysis of RCTs failed to show any differences between the two arms (RR 0.90, 95% CI 0.62-1.30, p= 0.57; Heterogeneity: I2 88%, p: 0.0002). CONCLUSIONS: Adenosine-guided radiofrequency catheter ablation of atrial fibrillation does not provide additional benefit in terms of freedom of arrhythmia recurrence.

Efficacy and safety of novel anticoagulants in the elderly.

Atrial fibrillation and venous thromboembolism (VTE) are common disorders associated with maleficent thrombotic events, particularly in the elderly patients. Polypharmacy, co-morbidities, and altered pharmacokinetics, often present in these patients, render the use of anticoagulants quite challenging. Novel oral anticoagulants (NOACs) have recently emerged as alternatives to Vitamin K Antagonists (VKAs) and are gradually increasing their popularity mainly because of their fewer drug and food interactions and ease of use. Their effectiveness and safety has been well-established in the general population but the balance between benefit and harm in the elderly is still unclear. Routine use in these patients is uncommon. Accumulating data have shown that the benefit of NOACs is consistent among all age groups, featuring equal or greater efficacy in preventing thrombotic events. Excess bleedings were lower with NOACs in comparison to VKAs, but bleeding patterns were disparate among them and head to head comparison is not available. The present review highlights on the efficacy and safety of novel anticoagulants in the elderly population.

Adenosine-Guided Pulmonary Vein Antral Isolation for Paroxysmal Atrial Fibrillation: A Randomized Study.

OBJECTIVES: The prognostic significance of adenosine-mediated pulmonary vein (PV) dormant conduction and whether such conduction should be eliminated still remain controversial. This randomized study aimed to investigate whether adenosine-guided ablation of the reconnection gaps improves the long-term outcomes of pulmonary vein antral isolation (PVAI) for paroxysmal atrial fibrillation (AF). METHODS AND RESULTS: Consecutive patients with paroxysmal AF were randomly assigned to undergo (n = 80, group 1) or not (n = 81, group 2) adenosine testing following PVAI. Adenosine-mediated PV dormant conduction was unmasked in 26 patients (32.5%) of group 1. Successful elimination of the reconnection gaps was subsequently performed in all patients. During a mean follow-up period of 11.39 ± 5.10 months, 30 patients of group 1 (37.5%), and 27 patients of group 2 (33.3%) experienced arrhythmia recurrence. The Kaplan-Meier arrhythmia free survival curves failed to demonstrate any significant differences between study groups (log rank 0.217, P = 0.642). Fourteen of 26 (53.8%) patients with adenosine-mediated dormant conduction and subsequent elimination of reconnection gaps experienced AF recurrence during follow-up. On the contrary, only 16 of 54 patients without dormant conduction (29.6%) displayed arrhythmia recurrence (P = 0.049). Logistic regression analysis showed that adenosine-mediated PV reconnection (hazard ratio 0.292, 95% confidence interval 0.122-0.483; P = 0.01) was an independent predictor of AF recurrence. CONCLUSION: In this patients' cohort, adenosine-mediated PV reconnection is predictive of future arrhythmic events. Elimination of dormant conduction with additional ablation lesions does not improve the long-term outcome of the procedure compared to the standard PVAI.

Colchicine for prevention of early atrial fibrillation recurrence after pulmonary vein isolation: a randomized controlled study.

OBJECTIVES: The purpose of the present study was to test the potential of colchicine, an agent with potent anti-inflammatory action, to reduce atrial fibrillation (AF) recurrence after pulmonary vein isolation in patients with paroxysmal AF. BACKGROUND: Proinflammatory processes induced by AF ablation therapy have been implicated in postablation arrhythmia recurrence. METHODS: Patients with paroxysmal AF who received radiofrequency ablation treatment were randomized to a 3-month course of colchicine 0.5 mg twice daily or placebo. C-reactive protein (CRP) and interleukin (IL)-6 levels were measured on day 1 and on day 4 of treatment. RESULTS: In the 3-month follow-up, recurrence of AF was observed in 27 (33.5%) of 80 patients of the placebo group versus 13 (16%) of 81 patients who received colchicine (odds ratio: 0.38, 95% confidence interval: 0.18 to 0.80). Gastrointestinal side-effects were the most common symptom among patients receiving active treatment. Diarrhea was reported in 7 patients in the colchicine group (8.6%) versus 1 in the placebo group (1.3%, p = 0.03). Colchicine led to higher reductions in CRP and IL-6 levels: the median difference of CRP and IL-6 levels between days 4 and 1 was -0.46 mg/l (interquartile range: -0.78 to 0.08 mg/l) and -0.10 mg/l (-0.30 to 0.10 pg/ml), respectively, in the placebo group versus -1.18 mg/l (-2.35 to -0.46 mg/l) and -0.50 pg/ml (-1.15 to -0.10 pg/ml) in the colchicine group (p < 0.01 for both comparisons). CONCLUSIONS: Colchicine is an effective and safe treatment for prevention of early AF recurrences after pulmonary vein isolation in the absence of antiarrhythmic drug treatment. This effect seems to be associated strongly with a significant decrease in inflammatory mediators, including IL-6 and CRP.

Novel indexes of heterogeneity of ventricular repolarization in subjects with early repolarization pattern.

AIM: The presence of early repolarization (ER) in inferior or inferolateral leads has been associated with malignant arrhythmias and increased mortality. Transmural dispersion of repolarization (TDR) has been proposed to underlie arrhythmogenesis in J-wave syndromes. The present study investigated specific electrocardiographic (ECG) markers including Tpeak-Tend interval and (Tpeak-Tend)/QT ratio that reflect TDR in subjects with ER. METHODS AND RESULTS: The ECGs of 47 healthy individuals (43 males, mean age: 45.7 ± 13.1 years) with an ER pattern in lateral (n = 15) or infero-lateral leads (n = 32) who successfully completed an exercise stress test were analysed at rest, peak workload, and recovery. The ER pattern was defined as slurring or notching of the terminal part of the QRS complex (J-point) ≥ 1 mm, in at least two contiguous leads. Thirty-five age- and sex-matched healthy subjects without ER (28 males, mean age: 48.6 ± 10.2 years) served as comparative controls. Subjects with ER displayed increased Tpeak-Tend interval in lead V(2), Tpeak-Tend dispersion of the precordial leads, and (Tpeak-Tend)/QT ratio in lead V(2) compared with those without ER in all three phases of the exercise test (P < 0.05). In addition, Tpeak-Tend dispersion and the (Tpeak-Tend)/QT ratio in lead V(2) were significantly increased at recovery phase compared with peak exercise only in subjects with ER (P< 0.05). There were no significant differences among the studied ECG parameters regarding the ER location (lateral vs. infero-lateral), the ER type (slurring or notching), or the maximum J-point amplitude (≥ 1.5 vs. <1.5 mm) at baseline ECGs. CONCLUSIONS: Individuals with ER display an increased TDR that may be related to an increased arrhythmic risk.

Anticoagulation and antiplatelet therapy in implantation of electrophysiological devices.

The growing implantations of electrophysiological devices in the context of increasing rates of chronic antithrombotic therapy in cardiovascular disease patients underscore the importance of an effective periprocedural prophylactic strategy for prevention of bleeding complications. In this review, we provide a concise overview of the data regarding anticoagulation and antiplatelet therapy in arrhythmia device surgery. Also, we critically discuss risk factors and procedural parameters that are potentially associated with haemorrhagic untoward events in this setting. Of note, current evidence suggests that heparin bridging therapy in patients on chronic anticoagulation and dual-antiplatelet therapy are associated with increased risk of pocket haematoma formation. Continuation of oral anticoagulation and short-term interruption of clopidogrel with aspirin maintenance in eligible patients, respectively, represent promising strategies with an acceptable safety profile. Besides the perioperative management of antithrombotic therapy, some extra supportive measures may also reduce the incidence of haematomas. High-risk cases should be better treated by experienced operators in high-volume centres. More randomized studies are needed to elucidate the exact role of particular antithrombotic therapy protocols. Finally, the recently accumulated data on this subject should be incorporated into the professional guidelines regarding arrhythmia device therapy.

Epsilon-like waves and ventricular conduction abnormalities in subjects with type 1 ECG pattern of Brugada syndrome.

BACKGROUND: Previous studies have demonstrated an overlap between the arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) and Brugada syndrome (BS). Conduction delay in the right ventricle has been demonstrated in both entities. OBJECTIVE: This study investigated specific ARVC/D electrocardiographic (ECG) markers in subjects with spontaneous or drug-induced type 1 ECG pattern of BS. METHODS: The study population consisted of 47 apparently healthy individuals (38 men, mean age 44.1 ± 13.3 years) with spontaneous (n = 17) or drug-induced (n = 30) type 1 ECG phenotype of BS. The clinical records of these individuals were retrospectively analyzed. RESULTS: Fifteen subjects (31.9%) were symptomatic, with a history of syncope. A family history of BS or sudden cardiac death was reported in 10 (21.3%) and 8 (17.0%) cases, respectively. Epsilon-like waves in leads V1-V3 were observed in 6 subjects (12.7%). Epsilon-like waves were seen in spontaneous type 1 ECGs in 2 cases and after sodium channel blocking test in 4 cases. In baseline ECGs, localized prolongation (>110 ms) of the QRS complex in leads V1-V3, QRS duration ratio in (V1+V2+V3)/(V4+V5+V6) ≥ 1.2, and prolonged S wave upstroke (>55 ms) in leads V1-V3 were seen in 48.8%, 29.8%, and 40.4% of subjects, respectively. Epsilon-like waves and delayed S wave upstroke were more commonly observed in subjects with family history of BS (P = .014 and P = .038, respectively). CONCLUSION: Specific ECG markers that reflect ventricular conduction delay in ARVC/D are commonly observed in subjects with spontaneous or drug-induced type 1 ECG pattern of BS as well. These depolarization abnormalities may be related to subtle underlying structural abnormalities.

The natural history of arrhythmogenic right ventricular cardiomyopathy.

The authors describe the case of a 66-year-old woman with arrhythmogenic right ventricular dysplasia masqueraded as dilated cardiomyopathy. Her medical history included recurrent episodes of syncope beginning at the age of 28. The natural history of the disease is discussed.