Christelle Marquié

Outcome After Implantation of a Cardioverter-Defibrillator in Patients With Brugada Syndrome A Multicenter Study

Background— Implantable cardioverter-defibrillator indications in Brugada syndrome remain controversial, especially in asymptomatic patients. Previous outcome data are limited by relatively small numbers of patients or short follow-up durations. We report the outcome of patients with Brugada syndrome implanted with an implantable cardioverter-defibrillator in a large multicenter registry. Methods and Results— A total of 378 patients (310 male; age, 46±13 years) with a type 1 Brugada ECG pattern implanted with an implantable cardioverter-defibrillator (31 for aborted sudden cardiac arrest, 181 for syncope, and 166 asymptomatic) were included. Fifteen patients (4%) were lost to follow-up. During a mean follow-up of 77±42 months, 7 patients (2%) died (1 as a result of an inappropriate shock), and 46 patients (12%) had appropriate device therapy (5±5 shocks per patient). Appropriate device therapy rates at 10 years were 48% for patients whose implantable cardioverter-defibrillator indication was aborted sudden cardiac arrest, 19% for those whose indication was syncope, and 12% for the patients who were asymptomatic at implantation. At 10 years, rates of inappropriate shock and lead failure were 37% and 29%, respectively. Inappropriate shock occurred in 91 patients (24%; 4±4 shocks per patient) because of lead failure (n=38), supraventricular tachycardia (n=20), T-wave oversensing (n=14), or sinus tachycardia (n=12). Importantly, introduction of remote monitoring, programming a high single ventricular fibrillation zone (>210–220 bpm), and a long detection time were associated with a reduced risk of inappropriate shock. Conclusions— Appropriate therapies are more prevalent in symptomatic Brugada syndrome patients but are not insignificant in asymptomatic patients (1%/y). Optimal implantable cardioverter-defibrillator programming and follow-up dramatically reduce inappropriate shock. However, lead failure remains a major problem in this population.

Outcome After Implantation of a Cardioverter-Defibrillator in Patients With Brugada Syndrome

Background— Brugada syndrome is an arrhythmogenic disease characterized by an increased risk of sudden cardiac death (SCD) by ventricular fibrillation. At present, an implantable cardioverter-defibrillator (ICD) is the recommended therapy in high-risk patients. This multicenter study reports the outcome of a large series of patients implanted with an ICD for Brugada syndrome. Methods and Results— All patients (n=220, 46±12 years, 183 male) with a type 1 Brugada ECG pattern implanted with an ICD in 14 centers between 1993 and 2005 were investigated. ICD indication was based on resuscitated SCD (18 patients, 8%), syncope (88 patients, 40%), or positive electrophysiological study in asymptomatic patients (99 patients, 45%). The remaining 15 patients received an ICD because of a family history of SCD or nonsustained ventricular arrhythmia. During a mean follow-up of 38±27 months, no patient died and 18 patients (8%) had appropriate device therapy (10±15 shocks/patient, 26±33 months after implantation). The complication rate was 28%, including inappropriate shocks, which occurred in 45 patients (20%, 4±3 shocks/patient, 21±20 months after implantation). The reasons for inappropriate therapy were lead failure (19 patients), T-wave oversensing (10 patients), sinus tachycardia (10 patients), and supraventricular tachycardia (9 patients). Among implantation parameters, high defibrillation threshold, high pacing threshold, and low R-wave amplitude occurred, respectively, in 12%, 27%, and 15% of cases. Conclusion— In this large Brugada syndrome population, a low incidence of arrhythmic events was found, with an annual event rate of 2.6% during a follow-up of >3 years, in addition to a significant risk of device-related complications (8.9%/year). Inappropriate shocks were 2.5 times more frequent than appropriate ones.

Outcome After Implantation of a Cardioverter-Defibrillator in Patients With Brugada SyndromeClinical Perspective: A Multicenter Study–Part 2

Background— Implantable cardioverter-defibrillator indications in Brugada syndrome remain controversial, especially in asymptomatic patients. Previous outcome data are limited by relatively small numbers of patients or short follow-up durations. We report the outcome of patients with Brugada syndrome implanted with an implantable cardioverter-defibrillator in a large multicenter registry. Methods and Results— A total of 378 patients (310 male; age, 46±13 years) with a type 1 Brugada ECG pattern implanted with an implantable cardioverter-defibrillator (31 for aborted sudden cardiac arrest, 181 for syncope, and 166 asymptomatic) were included. Fifteen patients (4%) were lost to follow-up. During a mean follow-up of 77±42 months, 7 patients (2%) died (1 as a result of an inappropriate shock), and 46 patients (12%) had appropriate device therapy (5±5 shocks per patient). Appropriate device therapy rates at 10 years were 48% for patients whose implantable cardioverter-defibrillator indication was aborted sudden cardiac arrest, 19% for those whose indication was syncope, and 12% for the patients who were asymptomatic at implantation. At 10 years, rates of inappropriate shock and lead failure were 37% and 29%, respectively. Inappropriate shock occurred in 91 patients (24%; 4±4 shocks per patient) because of lead failure (n=38), supraventricular tachycardia (n=20), T-wave oversensing (n=14), or sinus tachycardia (n=12). Importantly, introduction of remote monitoring, programming a high single ventricular fibrillation zone (>210–220 bpm), and a long detection time were associated with a reduced risk of inappropriate shock. Conclusions— Appropriate therapies are more prevalent in symptomatic Brugada syndrome patients but are not insignificant in asymptomatic patients (1%/y). Optimal implantable cardioverter-defibrillator programming and follow-up dramatically reduce inappropriate shock. However, lead failure remains a major problem in this population.

Contributions of remote monitoring to the follow-up of implantable cardioverter–defibrillator leads under advisory

Aims Automatic daily transmission of data from implantable cardioverter–defibrillators (ICDs) enables the remote monitoring of device status and leads function. We report on a 2-year experience with remote monitoring in 40 recipients of high-voltage ICD leads, prone to fracture and under advisory since October 2007. Methods and results The ICDs were remotely monitored as well as systematically interrogated in the ambulatory department every 3 months. The patients were also seen in case of abnormal lead impedance, or other manifestations consistent with lead dysfunction. Over a mean follow-up of 22 ± 4 months after ICD implantation, four lead dysfunctions were suspected because of remotely transmitted oversensing of noise artifacts, abrupt rise in pacing impedance, or both. A lead fracture needing lead replacement was confirmed in three patients (7.5%), two of them before any inappropriate therapy and one after the delivery of three inappropriate shocks. No lead failure was observed in the remaining 36 patients, either at the time of ambulatory visits or during remote monitoring. Conclusion Remote monitoring allowed the early and reliable detection of ICD leads failure without requiring any patient intervention.

Prevalence and prognostic significance of psychiatric disorders in patients evaluated for recurrent unexplained syncope.

We aimed to assess the psychiatric profile and prognostic value of psychiatric disorders (PDs) in patients presenting with unexplained syncope. Forty patients with recurrent unexplained syncope referred for head-up tilt testing were compared with age- and sex-matched patients free of known chronic PDs referred for arrhythmia. All patients underwent a semistandardized psychiatry questionnaire (Mini-International Neuropsychiatric Interview) to assess their profile. Additional stress coping was performed to study adaptational processes to stressful situations. After tilt testing and psychiatric evaluation, a drug-free follow-up was performed in patients with syncope. Of the 80 patients who referred to the psychiatric interview, 40 had evidence of at least 1 psychiatric disorder. They were 26 patients (65%) in the syncope group and 14 patients (35%) in the control group (p = 0.01). Detailed analysis revealed a more frequent subprofile of anxiety and panic disorders in patients with syncope than in controls (30% vs 12% and 20% vs 10%, respectively), whereas the subprofile of depression was similar in both groups. Moreover, those with syncope were more likely to have a high anxiety index (25 +/- 5 vs 22 +/- 4, p = 0.004), and were more prone to avoidance-oriented coping strategies when experiencing undesirable life events than controls. Considering syncope patients, no difference could be found between the 25 with a positive tilt test and the 15 with a negative tilt test with respect to the number of syncopal episodes and psychiatric profile. After a 3-year drug-free follow-up, 15 patients (37.5%) had at least 1 recurrent syncope. The recurrence rate was similar in patients with positive and negative head-up tilt test results (9 of 25 vs 6 of 15, respectively). In contrast, the syncopal recurrence rate was higher in patients who fulfilled criteria for affective disorders (13 of 26 vs 2 of 14, 95% confidence interval 1.09 to 2.55, relative risk 1.7, p = 0.04). Thus, patients with recurrent unexplained syncope are more anxious and are more prone to panic disorders and avoidance-oriented coping strategies than control patients with arrhythmia. The presence of a psychiatric disorder is associated with an increased risk of recurrence. The outcome of such patients may be improved with recognition and treatment of PDs.

Extraction of Old Pacemaker or Cardioverter-Defibrillator Leads by Laser Sheath Versus Femoral Approach

Background—Some operators routinely extract chronically implanted transvenous leads from a femoral, whereas others prefer a superior approach. This prospective study compared the safety and effectiveness of laser sheaths versus femoral snare extractions. Methods and Results—The single-center study comprised 101 patients referred for unequivocal indications to extract ≥1 transvenous lead(s). Patients were >4 years of age and were randomly assigned to extractions with a laser sheath (group 1: n=50) versus a snare via femoral approach (group 2: n=51). The multicenter study comprised 358 patients who underwent extraction of old transvenous leads using laser sheaths (n=218, group 3) in 3 centers and from a femoral approach (n=138, group 4) in 3 other centers. In the single-center study, the success and complications rates were similar in groups 1 and 2. No patient died of a periprocedural complication. The procedural duration (51±22 versus 86±51 minutes) and duration of total fluoroscopic exposure (7±7 versus 21±17 minutes) were significantly shorter (each P<0.01) in group I than in group 2. In the multicenter study, we observed 2 procedure-associated deaths in group 3 versus 1 in group 4. Major procedural complications were observed in 3% of patients in group 3, versus 3% in group 4 (P=NS). The rates of complete, partial, and unsuccessful extractions were similar in groups 3 and 4. Conclusions—Old transvenous leads were extracted with similar success and complication rates by the femoral and laser approaches. However, the femoral approach was associated with longer procedures and a longer duration of fluoroscopic exposure.

Pacemaker lead extraction with the needle's eye snare for countertraction via a femoral approach.

KLUG, D., et al.: Pacemaker Lead Extraction with the Needles Eye Snare for Countertraction via a Femoral Approach. Femoral approach pacemaker lead extraction is described as a safe and efficacious procedure. When the lead can not be removed from its myocardial insertion, the “Needles eye snare” has become available, and it allows a femoral approach traction associated with a countertraction . Between May 1998 and May 2000, 222 lead extraction procedures were performed in 99 patients using the femoral approach. This article reports the results of the 70 lead extractions requiring the use of the Needles eye snare for femoral approach countertraction in 39 patients with a total of 82 leads. The indications were infection, accufix leads and lead dysfunction in 56, 1 and 6 leads, respectively. The age of the leads was 113 ± 56 months. Sixty‐one (87.2%) leads were successfully extracted, the extraction was incomplete in 3 (4.3%) cases and failed in 6 (8.5%) cases. The failures were due to leads totally excluded from the venous flow for four leads, the impossibility of advancing the 16 Fr long sheath through the right and left iliac veins for one lead and one traction induced a nontolerated ventricular arrhythmia. In these cases, an extraction by a simple upper traction had been attempted in another center several months before. The complications included two deaths and one transient ischemia of the right inferior limb. Despite the selection of a series of leads for which an extraction by a simple traction on the proximal end of the lead was impossible or unsuccessful, femoral countertraction seems to be a safe and efficacious procedure. The failure of this technique occurred in patients with damaged leads due to a previous extraction procedure performed in centers with limited experience in lead extraction.

Decreased Delivery of Inappropriate Shocks Achieved by Remote Monitoring of ICD: A Substudy of the ECOST Trial

Inappropriate shocks remain a highly challenging complication of implantable cardioverter defibrillators (ICD). We examined whether automatic wireless remote monitoring (RM) of ICD, by providing early notifications of triggering events, lowers the incidence of inappropriate shocks.

Cardiac resynchronisation therapy reduces functional mitral regurgitation during dynamic exercise in patients with chronic heart failure: an acute echocardiographic study

Objectives: To assess non-invasively the acute effects of cardiac resynchronisation therapy (CRT) on functional mitral regurgitation (MR) at rest and during dynamic exercise. Methods: 21 patients with left ventricular (LV) systolic dysfunction and functional MR at rest, treated with CRT, were studied. Each patient performed a symptom-limited maximal exercise with continuous two dimensional Doppler echocardiography twice. The first exercise was performed with CRT; the second exercise was performed without CRT. Mitral regurgitant flow volume (RV), effective regurgitant orifice area (ERO) and LV dP/dt were measured at rest and at peak exercise. Results: CRT mildly reduced resting mitral ERO (mean 8 (SEM 2) v 11 (2) mm2 without CRT, p  =  0.02) and RV (13 (3) v 18 (3) ml without CRT, p  =  0.03). CRT attenuated the spontaneous increase in mitral ERO and RV during exercise (1 (1) v 9 (2) mm2, p  =  0.004 and 1 (1) v 8 (2) ml, p  =  0.004, respectively). CRT also significantly increased exercise-induced changes in LV dP/dt (140 (46) v 479 (112) mm Hg/s, p < 0.001). Conclusion: Attenuation of functional MR, induced by an increase in LV contractility during dynamic exercise, may contribute to the beneficial clinical outcome of CRT in patients with chronic heart failure and LV asynchrony.

The PPARα activator fenofibrate slows down the progression of the left ventricular dysfunction in porcine tachycardia-induced cardiomyopathy

It has been reported that high intramyocardial peroxisome proliferator-activated receptor α (PPARα) stimulation or overexpression altered cardiac contractile function in mouse models of cardiac hypertrophy and heart failure. Nevertheless, it has never been demonstrated that clinically relevant doses of drugs stimulating PPARα activity such as fenofibrate increase the risk to develop heart failure in humans. To determine if fenofibrate accelerates the development of heart failure in large mammals, we have tested its effects on the progression of left ventricular dysfunction in pacing-induced heart failure in pigs. Fenofibrate treatment blunted reduction in left ventricular ejection fraction, reduced cardiac hypertrophy, and attenuated clinical signs of heart failure. Fenofibrate impeded the increase in atrial natriuretic peptide, brain natriuretic peptide, and endothelin-1 plasma levels. The expression of PPARα, fatty acyl-CoA-oxidase, and carnitine palmitoyltransferase-Iβ was reduced at mRNA levels in the left ventricle from untreated heart failure pigs but maintained near normal values with fenofibrate. Fenofibrate prevented heart failure-induced overexpression of TNFα mRNA and enhanced catalase activity in left ventricle compared to placebo. These data suggest that a clinically relevant dose of fenofibrate does not accelerate but slows down heart failure development in the model of pacing-induced heart failure in large mammals.