Jean-Sylvain Hermida

Prevalence of the Brugada syndrome in an apparently healthy population

The syndrome associating right bundle branch block, ST-segment elevation in leads V1, V2 to V3, and aborted sudden cardiac death due to ventricular fibrillation was first reported in 1992 by Brugada and Brugada. Mutations in SCN5A, a gene encoding the cardiac sodium channel, have been evidenced in some patients. Usually, the ST-segment elevation has a coved form, but change into a saddleback form or complete normalization appear to be common (30%), leading to underdiagnosis of the syndrome. The right bundle branch shows varying degrees of conduction disturbances, and in some cases the right bundle branch block can be absent. In patients in whom the syndrome is suspected despite a normal electrocardiogram, ST-segment elevation can be reproduced by ajmaline. According to Brugada, asymptomatic patients recognized at random or discovered in a family study, have a 27% incidence of arrhythmic events during a mean follow-up of 34 months. A coved ST-segment elevation has been also observed in patients with arrhythmogenic right ventricular dysplasia, in Chagas or Steinert diseases, and in mediastinal tumors. Also, the early repolarization syndrome may show some electrocardiographic similarities with the saddleback type of Brugada syndrome. Consequently, the clinical significance of the different types of ST-segment elevations may appear uncertain in asymptomatic patients, especially in a patient with the isolated saddleback type. The disease is the most common cause of sudden cardiac death in young persons in south Asia. In Japan, the prevalence of electrocardiograms compatible with the syndrome is 0.05%. In Europe, the disease has been recognized recently and there are no data available on its prevalence. Currently, the implantable cardiac defibrillator is the only effective treatment and is indicated in symptomatic patients; it should be considered in asymptomatic patients in whom polymorphic sustained ventricular tachycardia is inducible during electrophysiologic study. This study assesses the prevalence of the electrocardiographic patterns of the Brugada syndrome in an apparently healthy, asymptomatic, European population, and determines whether these patterns were associated with increased cardiac mortality.

A randomized study of remote follow-up of implantable cardioverter defibrillators: safety and efficacy report of the ECOST trial

Aims The ECOST trial examined prospectively the long-term safety and effectiveness of home monitoring (HM) of implantable cardioverter defibrillators (ICD). Methods and results The trials primary objective was to randomly compare the proportions of patients experiencing ≥1 major adverse event (MAE), including deaths from all causes, and cardiovascular, procedure-related, and device-related MAE associated with HM (active group) vs. ambulatory follow-ups (control group) in a sample of 433 patients. The 221 patients assigned to the active group were seen once a year, unless HM reported an ICD dysfunction or a clinical event requiring an ambulatory visit, while the 212 patients in the control group underwent ambulatory visits every 6 months. The characteristics of the study groups were similar. Over a follow-up of 24.2 months, 38.5% of patients in the active and 41.5% in the control group experienced ≥1 MAE (P < 0.05 for non-inferiority). The overall number of shocks delivered was significantly lower in the active (n = 193) than in the control (n = 657) group (P < 0.05) and the proportion of patients who received inappropriate shocks was 52% lower in the active (n = 11) than in the control (n = 22) group (P < 0.05). At the end of the follow-up, the battery longevity was longer in the active group because of a lower number of capacitor charges (499 vs. 2081). Conclusion Our observations indicate that long-term HM of ICD is at least as safe as standard ambulatory follow-ups with respect to a broad spectrum of MAE. It also lowered significantly the number of appropriate and inappropriate shocks delivered, and spared the device battery. Clinical trials registration NCT00989417.

Causes-of-death analysis of patients with cardiac resynchronization therapy: an analysis of the CeRtiTuDe cohort study

Aims The choice of resynchronization therapy between with (CRT-D) and without (CRT-P) a defibrillator remains a contentious issue. Cause-of-death analysis among CRT-P, compared with CRT-D, patients could help evaluate the extent to which CRT-P patients would have additionally benefited from a defibrillator in a daily clinical practice. Methods and results A total of 1705 consecutive patients implanted with a CRT (CRT-P: 535 and CRT-D: 1170) between 2008 and 2010 were enrolled in CeRtiTuDe, a multicentric prospective follow-up cohort study, with specific adjudication for causes of death at 2 years. Patients with CRT-P compared with CRT-D were older (P < 0.0001), less often male (P < 0.0001), more symptomatic (P = 0.0005), with less coronary artery disease (P = 0.003), wider QRS (P = 0.002), more atrial fibrillation (P < 0.0001), and more co-morbidities (P = 0.04). At 2-year follow-up, the annual overall mortality rate was 83.80 [95% confidence interval (CI) 73.41–94.19] per 1000 person-years. The crude mortality rate among CRT-P patients was double compared with CRT-D (relative risk 2.01, 95% CI 1.56–2.58). In a Cox proportional hazards regression analysis, CRT-P remained associated with increased mortality (hazard ratio 1.54, 95% CI 1.07–2.21, P = 0.0209), although other potential confounders may persist. By cause-of-death analysis, 95% of the excess mortality among CRT-P subjects was related to an increase in non-sudden death. Conclusion When compared with CRT-D patients, excess mortality in CRT-P recipients was mainly due to non-sudden death. Our findings suggest that CRT-P patients, as currently selected in routine clinical practice, would not potentially benefit with the addition of a defibrillator.

Normal pulmonary veins anatomy is associated with better AF-free survival after cryoablation as compared to atypical anatomy with common left pulmonary vein.

Background: Pulmonary vein cryoablation (PVC) is a new approach in the treatment of recurrent atrial fibrillation (AF). Computed tomography (CT) can be used to evaluate the left atrium anatomy and PVs dimensions to facilitate the procedure. In radiofrequency procedures, some anatomic variants such as common left (CLPV) or right (CRPV) PV were reported as factors associated with technical procedure difficulties and potential long‐term complications. We hypothesized that the absence of CLPV as determined by CT would predict better AF‐free survival after PVC.

Familial incidence of late ventricular potentials and electrocardiographic abnormalities in arrhythmogenic right ventricular dysplasia

Familial forms of arrhythmogenic right ventricular dysplasia (ARVD) have been described. Signal-averaged electrocardiograms (SAECGs) and standard electrocardiograms have been used to detect ARVD. The purpose of this prospective study, for a given family member, was to evaluate the risk of having ARVD or only belonging to an affected family. To address these issues, we assessed the incidence of late ventricular potentials and electrocardiographic (ECG) abnormalities in the families of our patients with ARVD. SAECGs and electrocardiograms were recorded in 101 eligible family members and compared with those recorded in ARVD patients with sustained ventricular tachycardia (13 patients in 12 families), and in 37 control subjects with a normal electrocardiogram. The incidence of late ventricular potentials was significantly higher in family members than in control subjects (16% vs 3%, p <0.05). The incidence of ECG abnormalities was 34% in family members. When the incidence of late ventricular potentials and/or ECG abnormalities were added up, results were 38% abnormal findings in family members. Late ventricular potentials and/or ECG abnormalities were found in members of all 7 families; these abnormalities were initially thought to be sporadic forms, and thereafter were classified as familial forms. Thus, SAECGs and standard ECG recordings in ARVD family members showed 38% abnormal findings, and that all cases of ARVD could be classified as familial forms. The incidence of familial forms of ARVD was greater than was previously believed, which is highly suggestive of a genetic transmission of the disease in our geographic area.

Costs of remote monitoring vs. ambulatory follow-ups of implanted cardioverter defibrillators in the randomized ECOST study

Aims The Effectiveness and Cost of ICD follow-up Schedule with Telecardiology (ECOST) trial evaluated prospectively the economic impact of long-term remote monitoring (RM) of implantable cardioverter defibrillators (ICDs). Methods and results The analysis included 310 patients randomly assigned to RM (active group) vs. ambulatory follow-ups (control group). Patients in the active group were seen once a year unless the system reported an event mandating an ambulatory visit, while patients in the control group were seen in the ambulatory department every 6 months. The costs of each follow-up strategy were compared, using the actual billing documents issued by the French health insurance system, including costs of (i) (a) ICD-related ambulatory visits and transportation, (b) other ambulatory visits, (c) cardiovascular treatments and procedures, and (ii) hospitalizations for the management of cardiovascular events. The ICD and RM system costs were calculated on the basis of the device remaining longevity at the end of the study. The characteristics of the study groups were similar. Over a follow-up of 27 months, the mean non-hospital costs per patient-year were €1695 ± 1131 in the active, vs. €1952 ± 1023 in the control group (P = 0.04), a €257 difference mainly due to device management. The hospitalization costs per patient-year were €2829 ± 6382 and €3549 ± 9714 in the active and control groups, respectively (P = 0.46). Adding the ICD to the non-hospital costs, the savings were €494 (P = 0.005) or, when the monitoring system was included, €315 (P = 0.05) per patient-year. Conclusion From the French health insurance perspective, the remote management of ICD patients is cost saving. Clinical trials registration NCT00989417, www.clinicaltrials.gov

Long-term follow-up of asymptomatic Brugada patients with inducible ventricular fibrillation under hydroquinidine

AIMS To evaluate the long-term efficacy and safety of an electrophysiologically guided therapy, based on a strategy of treatment using hydroquinidine (HQ) among asymptomatic Brugada patients with inducible ventricular fibrillation (VF). METHODS AND RESULTS In two French reference centres, consecutive asymptomatic type 1 Brugada patients with inducible VF were treated with HQ (600 mg/day, targeting a therapeutic range between 3 and 6 µmol/L) and enroled in a specific follow-up (mean 6.6 ± 3 years), including a second programmed ventricular stimulation (PVS) under HQ. An implantable cardioverter defibrillator (ICD) was eventually implanted in patients inducible under HQ, or during follow-up in case of HQ intolerance, as well as occurrence of arrhythmic events. From a total of 397 Brugada patients, 44 were enroled (47 ± 10 years, 95% male). Of these, 34 (77%) were no more inducible (Group PVS-), and were maintained under HQ alone during a mean follow-up of 6.2 ± 3 years. In this group, an ICD was eventually implanted in four patients (12%), with occurrence of appropriate ICD therapies in one. Among the 10 other patients (22%), who remained inducible and received ICD (Group PVS+), none of them received appropriate therapy during a mean follow-up of 7.7 ± 2 years. The overall annual rate of arrhythmic events was 1.04% (95% confidence interval 0.00-2.21), without any significant difference according to the result of PVS under HQ. One-third of patients experienced device-related complications. CONCLUSION Our long-term follow-up results emphasize that the rate of arrhythmic events among asymptomatic Brugada patients with inducible VF remains low over time. Our results also suggest that residual inducibility under HQ is of limited value to predict events during follow-up.

Atrial Septal Versus Atrial Appendage Pacing: Feasibility and Effects on Atrial Conduction, Interatrial Synchronization, and Atrioventricular Sequence

HERMIDA, J.‐S., et al.: Atrial Septal Versus Atrial Appendage Pacing: Feasibility and Effects on Atrial Conduction, Interatrial Synchronization, and Atrioventricular Sequence. Atrial septal (Se‐P) and atrial appendage pacing (Ap‐P) were compared in a randomized, controlled study to assess the feasibility, the reliability, and the effects of Se‐P on atrial conduction, interatrial synchronization, and the AV sequence. The main baseline characteristics of the patients were comparable in both groups. There was no difference in feasibility or reliability between the two techniques. Compared to Ap‐P (n = 28) , Se‐P (n = 28) decreased the P wave duration, left atrial electromechanical delay (LAEMD), and interatrial interval (−1.6% vs +28%, P < 0.001; −3% vs + 30%, P < 0.001; −130% vs + 78%, P < 0.001 ); it induced a smaller increase of the right AEMD, a slight reversal of the timing of the atrial systoles and a shortening of the PR interval (−13% vs + 25%, P < 0.001 ) and of the interval separating atrial systoles from ventricular activation. Finally, the shortening of the PR interval was smaller during high Se‐P versus low Se‐P. Se‐P avoids the undesirable prolongation of the atrial, interatrial, and AV conductions observed during Ap‐P. In addition, Se‐P creates a slight reversal of the timing of the atrial systoles and induces a shortening of PR interval, the extent of which could depend on the height of the pacing site on the septum. (PACE 2003; 26[Pt. I]:26–35)

Coronary-to-bronchial artery communication: Report of two patients successfully treated by embolization

We report two cases of coronary-to-bronchial artery communication responsible for coronary steal. In both cases the anastomosis originated from the proximal circumflex artery and developed because of bronchiectasis. In both cases closure of the anastomosis was achieved successfully by embolization. To date, the patients remained free from symptoms.

Use of implantable loop recorders in patients with Brugada syndrome and suspected risk of ventricular arrhythmia.

AIMS Implantable cardioverter defibrillator (ICD) therapy is recommended in patients with Brugada syndrome (BS) who experienced aborted sudden cardiac death (SCD) or syncope while the risk stratification of ventricular arrhythmias is a difficult step in patients with atypical symptoms. Implantable loop recorder (ILR) use has been proposed to study patients with unexplained recurrent syncopal events, but its usefulness remains to be defined in patients with BS. In this retrospective study we aimed to investigate the effectiveness of ILR as a diagnostic tool in BS patients suspected of low or moderate risk of SCD. METHODS AND RESULTS We gathered data from 11 ILR recipients with supposed risk of ventricular arrhythmia, issue of Amiens registry of 204 patients with BS. We reported clinical events before and after implant, electrocardiogram (ECG) characteristics, ILR findings, and its limitations as well as tried to specify ILR utility in diagnosis approach and its consequent contribution to guide the optimal therapy. Within the 11 patients (8 men, 3 women), 9 were symptomatic, and 5 had a spontaneous Type 1 ECG pattern. During mean follow-up period of 33 months, 8 patients had a recurrence of symptoms with a mean delay of 9 months after implant. Bradycardia (two atrioventricular blocks and two sinus bradycardia) was detected in four out of eight patients (50%), and there was no ventricular arrhythmia in any patient during symptomatic events which included six vasovagal syncopes and two epileptic seizures. Two initially asymptomatic patients did not experience any symptoms after ILR implant and their ILR recordings did not reveal any arrhythmias. CONCLUSION The ILR contributed to the exclusion of a ventricular arrhythmia as a mechanism of an atypical syncope in patients with electrocardiographic BS and the suspension of the ICD implant. Episodes of transient symptomatic bradycardia were the most common findings suggesting the vagal mechanism of symptoms. The use of ILR should be considered in selected patients with atypical syncope and spontaneous or transient Type 1 ECG pattern.