How arrhythmic risk changes over time in patients with low risk Brugada syndrome

Background

Brugada Syndrome (BrS) is an inherited disorder associated with an increased risk of sudden cardiac death (SCD) and is diagnosed by the presence of a Brugada type I ECG pattern, either spontaneous or drug-induced. A spontaneous ECG pattern is one of the two main risk factors for SCD, along with syncope. However, there is still no clear evidence on how and how often to screen patients with drug-induced BrS to detect a spontaneous ECG pattern, therefore allowing to reassess their arrhythmic risk.

Purpose

To determine how many subjects develop a spontaneous ECG pattern among a pool of patients with low risk BrS (drug-induced pattern without history of syncope at the time of diagnosis) observed through systematic ECG Holter monitoring.

Methods

We retrospectively collected data for all patients with low risk BrS treated at our center for at least 12 months between 2016 and 2021. Each patient was tested yearly with at least one 12-lead 24-hour ECG Holter monitoring with high precordial leads (V1-V2, V3-V4, V5-V6 respectively in 2nd, 3rd and 4th intercostal space parasternal left and right). In case of spontaneous pattern detection at two recordings, patients underwent electrophysiological study (EPS) and in case of inducible ventricular arrhythmias, implantable cardiac defibrillator (ICD) placement.

Results

We included 63 patients with low risk BrS. During a median follow-up of 48 months: 1 patient died for SCD (1.6%), 1 experienced syncope (1.6%) and 19 exhibited a spontaneous ECG pattern (30.2%). Of these 19 patients: 18 were males and 5 had a mutation of SCN5A; the average age at the time of spontaneous pattern detection was 48.1±11.5 years. The average number of ECG holters/per patient/per year was 1.1±0.6, the average number of ECG Holters until the detection of a spontaneous pattern was 3.3±1.8, whilst the average number of months in between the diagnosis and the detection of a spontaneous pattern was 43.2±41.1.

After the observation of a spontaneous pattern: 6 patients were excluded from further investigation (as they had already undergone EPS or refused), 1 was directly treated with ICD and 12 underwent EPS, 4 of whom consequently underwent ICD placement. Among these 5 patients who underwent ICD placement – 7.9% of the original 63 patients – we observed 1 appropriate ICD intervention (antitachycardia pacing), 1 inappropriate ICD shock and 1 ICD related complication.

Conclusions

In our population of patients with low risk BrS the detection of a spontaneous ECG pattern is the most common determinant of risk reclassification. Systematic ECG Holter monitoring disclosed the presence of a spontaneous ECG pattern in a relevant number of subjects, allowing to reassess their arrhythmic risk and indication for ICD placement. Our study stresses the importance of periodic evaluation of low risk BrS patients with ECG Holter monitoring and the need for further investigation to define the optimal monitoring strategy.

Funding Acknowledgement

Type of funding sources: None.

Does corporate social responsibility impact equity risk? International evidence

Based on a large panel of listed firms from 52 countries in the period 2002–2020, we investigate the relationship between corporate social responsibility (CSR) and equity risk. We confirm previous evidence that higher CSR scores are related to lower risk measures, considering all types of risks: total, systematic, and idiosyncratic. Analyzing a large international sample allows us to investigate the role of country and company characteristics in the relationship between CSR scores and risk measures. The risk-reducing effect is more pronounced in weaker institutional environments. It is stronger in civil-law countries, in countries with low security regulation or disclosure requirement levels and where financial information is less widespread. Firms in high impact or high profile industries benefit more from CSR than firms in other industries as do firms that are not cross-listed. The financial crisis has increased the risk-reducing effect of CSR. The main results are confirmed in the COVID-19 period.

Remotely-driven management of diuretic therapy in heart failure patients with a multiparametric ICD algorithm

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Boston Scientific

Background

HeartLogic algorithm combines data from multiple sensors to predict future heart failure (HF) decompensation in patients with an implantable defibrillator (ICD) . An optimal strategy to manage algorithm alerts is not yet known, although decongestive treatment with diuretics is the most frequent alert-triggered action reported so far.

Purpose

We describe the implementation of HeartLogic for remote monitoring of HF patients, and we evaluate the approach to diuretic dosing and timing of the intervention in patients with device alerts.

Methods

The study was conducted in eight Italian high-volume arrhythmia centers. The algorithm was activated in 229 ICD patients during a median follow-up was 17 months [25th–75th percentile: 11-24] between December 2017 and July 2020. Remote data reviews and patient phone contacts were undertaken at the time of HeartLogic alerts, to assess the patient’s status and to prevent HF worsening. The study protocol did not mandate any specific intervention algorithm, and physicians were free to remotely implement clinical actions, to schedule extra in-office visits when deemed necessary for additional investigations or for interventions, or to adopt an active monitoring approach. We analyzed alert-triggered augmented HF treatments, consisting of isolated increases in diuretics dosage.

Results

We reported 242 alerts (0.8 alerts/patient-year) in 123 patients, 137 (56%) alerts triggered clinical actions to treat HF. Overall, timely diuretic changes were associated with a shorter "in-alert" state duration in comparison with late changes, i.e. 28 days [25th-75th percentile: 20-43] versus 62 days [25th-75th percentile: 44-118], p<0.001. By contrast, major and minor diuretic augmentations resulted in comparable durations, i.e. 47 days [25th-75th percentile: 30-58] versus 38 days [25th-75th percentile: 23-79], p=0.954. Of the 56 decongestive treatment adjustments, 47 resolved the alert condition, while in the remaining 9 cases, further treatments were required (augmented HF therapy during hospitalization or unscheduled intravenous decongestive therapy in outpatients). The need of hospitalization for further treatments to resolve the alert condition was associated with higher HeartLogic index values on the day of the diuretics increase (odds ratio: 1.11, 95%CI: 1.02-1.20, p=0.013) and with late interventions (odds ratio: 5.11, 95%CI: 1.09-24.48, p=0.041). No complications were reported after drug adjustments.

Conclusions

Decongestive treatment adjustments triggered by HeartLogic alerts, even when such adjustments were completely dependent on the physicians’ clinical expertise and were not standardized. The early use of decongestive treatment and the use of high doses of diuretics seem to be associated with more favorable outcomes.

Decongestive treatment adjustments in heart failure patients remotely monitored with a multiparametric implantable defibrillators algorithm

AIMS

HeartLogic algorithm combines data from multiple implantable defibrillators (ICD)-based sensors to predict impending heart failure (HF) decompensation. A treatment protocol to manage algorithm alerts is not yet known, although decongestive treatment adjustments are the most frequent alert-triggered actions reported in clinical practice. We describe the implementation of HeartLogic for remote monitoring of HF patients, and we evaluate the approach to diuretic dosing and timing of the intervention in patients with device alerts.

METHODS

The algorithm was activated in 229 ICD patients at eight centers. The median follow-up was 17 months (25th-75th percentile: 11-24). Remote data reviews and patient phone contacts were undertaken at the time of HeartLogic alerts, to assess the patient's status and to prevent HF worsening. We analyzed alert-triggered augmented HF treatments, consisting of isolated increases in diuretics dosage.

RESULTS

We reported 242 alerts (0.8 alerts/patient-year) in 123 patients, 137 (56%) alerts triggered clinical actions to treat HF. The HeartLogic index decreased after the 56 actions consisting of diuretics increase. Specifically, alerts resolved more quickly when the increases in dosing of diuretics were early rather than late: 28 days versus 62 days, p < .001. The need of hospitalization for further treatments to resolve the alert condition was associated with higher HeartLogic index values on the day of the diuretics increase (odds ratio: 1.11, 95% CI: 1.02-1.20, p = .013) and with late interventions (odds ratio: 5.11, 95% CI: 1.09-24.48, p = .041). No complications were reported after drug adjustments.

CONCLUSIONS

Decongestive treatment adjustments triggered by alerts seem safe and effective. The early use of decongestive treatment and the use of high doses of diuretics seem to be associated with more favorable outcomes.

Long-term outcome of catheter ablation for atrial fibrillation in patients with severe left atrial enlargement and reduced left ventricular ejection fraction

AIMS

Data regarding the efficacy of catheter ablation in heart failure patients with severely dilated left atrium and reduced left ventricular ejection fraction (LVEF) are scanty. We sought to assess the efficacy of catheter ablation in patients with reduced LVEF and severe left atrial (LA) enlargement, and to compare it to those patients with preserved left ventricular function and equally dilated left atrium.

METHODS AND RESULTS

Three patient groups with paroxysmal or persistent atrial fibrillation (AF) undergoing a first pulmonary vein isolation (PVI) were considered: Group 1 included patients with normal or mildly abnormal LA volume (≤41 mL/m2) and normal LVEF; Group 2 included patients with severe LA enlargement (>48 mL/m2) and normal LVEF; and Group 3 included patients with severe LA enlargement and reduced LVEF. Time to event analysis was used to investigate AF recurrences. The study cohort includes 439 patients; Group 3 had a higher prevalence of cardiovascular risk factors. LA enlargement was associated with a two-fold in risk of AF recurrence, on the contrary only a smaller non-significant increase of 30% was shown with the further addition of LVEF reduction.

CONCLUSIONS

The long-term outcome of patients with severe LA dilatation and reduced LVEF is comparable to those with severe LA enlargement but preserved LVEF. Long-term efficacy of PVI is certainly affected by the enlargement of the left atrium, but less so by the addition of a reduced LVEF. CA remains the best strategy for rhythm control both in paroxysmal and persistent AF in this subgroup of patients.

Long-term outcome of patients with cardiolaminopathy undergoing defibrillator implantation: single-center experience

Background

Mutations in the LMNA gene are associated with a high arrhythmic risk. The history of the disease in patients undergoing ICD implantation is poorly characterized.

Purpose

To evaluate the phenotype of patients with cardiolaminopathy at the time of first ICD implantation, the incidence, characteristics and timing of ventricular arrhythmias (VAs) during follow up and the predictive value of the European score (that assigns a point each to non-sustained VT (NSVT), left ventricular ejection fraction (LVEF)&lt;45% at first contact, male sex and non-missense mutations) and of the Wahbi score (that also includes conduction disturbances) for both VAs and heart failure (HF) related outcomes.

Methods

Patients were identified retrospectively. Clinical and device data were collected at baseline and during follow-up.

Results

We identified 26 patients (54% male, 42±8 years, 31% with familial history of sudden cardiac death, 31% with non-missense mutation) undergoing ICD implantation, 96% in primary prevention, 47% with single chamber ICD, 38% with dual chamber ICD. At the time of implantation, 30% had skeletal muscle involvement, 15% history of syncope, 4% of cardiac arrest, 62% previous NSVT. Also, 38% had a history of supraventricular arrhythmias and 61% had AV conduction disturbances. LVEF was 41±11%, 35% were in NYHA class ≥2, the mean European and Wahbi scores were 2.1±0.8 and 18.2±8.9, respectively. During 8.3±5 years, 15% were transplanted, 8% died due to HF, 4% underwent LVAD implantation, despite 31% having received an upgrade to CRT-D. Appropriate device interventions occurred in 46% of patients with a median time to first event of 29 months (IQR 13–93), for a total of 137 ATP, 51% of which effective (median 3ATP/patient, IQR 1–8) and of 26 shocks, 96% of which effective (median 2 shocks/patient, IQR 1–3); 12% had an arrhythmic storm. The first treated arrhythmia was a polymorphic VT/VF in 17%, a monomorphic VT in the others (medium cycle length 293±37 msec). Survival free from appropriate ICD interventions at 1 and at 5 years was 75% and 19% respectively in case of a European score ≥3 vs 94% and 82% in case of a score &lt;3 (Logrank test p&lt;0.01), 72% and 46% in case of Wahbi score ≥30 vs 100% and 86% with score &lt;30 (p&lt;0.01), with no differences in terms of death/transplant (figure). At last follow-up, 92% of patients a were taking beta-blocker, 42% amiodarone, 8% sotalol, 4% flecainide, 8% mexiletine. Also, 4% had undergone invasive VT ablation, 8% bilateral cardiac sympathetic denervation.

Conclusions

Patients with cardiolaminopathy are at a high risk of both arrhythmic and heart failure progression over the first decade after implantation of the first ICD. A European score ≥3 identifies patients with 5-year shock/ATP free survival of less than 20% but does not predict death/transplantation. The first arrhythmic event in these patients is more frequently a rapid monomorphic VT with modest ATP efficacy.

Funding Acknowledgement

Type of funding sources: None.

Catheter ablation versus antiarrhythmic drugs as first-line therapy for symptomatic atrial fibrillation: a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

In patients with symptomatic atrial fibrillation (AF), current international guidelines favor the use of antiarrhythmic drugs (AAD) as initial therapy for the maintenance of sinus rhythm. Previous studies have compared catheter ablation for pulmonary vein isolation versus AAD in this clinical scenario but the best first-line therapeutic option in patients with symptomatic AF candidates for rhythm control strategy remains an open issue.

Aim

To compare efficacy and safety of catheter ablation versus AAD as first-line therapy in patients with symptomatic AF.

Methods

We searched electronic databases for randomized controlled trials (RCTs) comparing catheter ablation versus AAD as first-line therapy for symptomatic AF. The primary efficacy outcome was any recurrence of atrial tachyarrhythmias. The secondary efficacy outcomes were symptomatic arrhythmic recurrences. The safety outcomes were serious adverse events related to the therapeutic regimen. Outcome events were defined according to the definition used in each original study. The effect size was estimated using a random-effect model as risk ratio (RR) and relative 95% confidence interval (CI) with the statistical software Review Manager 5.3.

Results

Five RCTs counting 997 patients (503 treated with catheter ablation and 494 with AAD) were included in the analysis. Mean age was 57 ± 3 years, 30% were female. Mean left ventricle ejection fraction was 60%±4% and mean left atrial diameter was 40 mm ± 1 mm. At baseline 52% of patients were treated with a beta-blocker and 11% with a calcium channel blocker. In the catheter ablation group 258 patients (51%) underwent cryoablation and 245 (49%) radiofrequency ablation. Median follow-up was 12 months (IQR 12-24 months). Patients treated with catheter ablation had statistically significant lower risk of atrial tachyarrhythmias recurrences (RR 0.59; 95%CI 0.45-0.76; p &lt; 0.0001 – Figure A) and of symptomatic arrhythmia recurrences (RR 0.45; 95%CI 0.25-0.80; p = 0.007 – Figure B) compared with those treated with AAD. The risk of serious adverse events related to the therapeutic regimen did not differ significantly between patients undergoing catheter ablations and those treated with AAD (RR 0.85; 95%CI 0.45-1.59 – Figure C).

Conclusions

In patients with symptomatic AF, catheter ablation as first-line therapy is associated with a reduced risk of atrial tachyarrhythmias recurrences compared with AAD, without statistically significant differences in the risk of serious adverse events related to the treatment. Abstract Figure.

Long-term follow-up of heart transplant patients treated with permanent pacemaker: a monocentric study

Funding Acknowledgements

Type of funding sources: None.

Background and purpose

Permanent pacemaker implantation (PPMi) is needed in about 5% of patients following heart transplant (HTx) primarily due to sinus node dysfunction (SND), which commonly occurs in an early phase, or to atrio-ventricular block (ABV), which is common later on. Currently, data on rate of ventricular pacing (VP) is lacking and little is known on long-term outcomes after PPMi.

Methods

This was a retrospective, monocentric study. Among 1123 patients treated with HTx, all with biatrial technique, from november 1985 to march 2019 at our institution, 61 (5.4%) patients needed PPMi. PM parameters, clinical and echocardiographic data were collected at 1 month and at 1-3-5-10 years follow-up. The primary aim was to analyse the percentage of right ventricular pacing in the overall population and in subgroups stratified by the timing of PPMi and by pacing indication. Secondary endpoints were to analyze long-term outcomes according to the percentage of ventricular pacing and to the type of implanted PM (single vs. dual chamber). 

Results

Among patients treated with PPMi (68.9% single-chamber), 62.2% were implanted for SND and 36% for AVB. Early PPMi (&lt; 3 months after HTx), occurred in 34.4% of patients, mainly due to SND, while late PPMi (&gt; 3 months after HTx) occurred in 65,6% with an equal distribution between SND and AVB. Median follow-up time from HTx was 140 months and 82 months from PPMi. Overall mean rate of VP was 21%. Rate of VP was higher in patients implanted early rather than late after HTx, both at 1 month (91% vs 2%, P = 0,002) and at 1 year after the procedure (43 vs 1, P = 0,037). Patients with AVB had a greater rate of VP compared to those implanted for SND, irrespective of timing of implantation and these findings were still present at 3 and 5 years follow-up (62 vs 1%, P = 0,011 at 3 years and 80 vs 6%, P = 0,002 at 5 years). VP declined progressively after PPM implantation. No differences were observed in terms of 10-years mortality between early vs late PPMi, dual vs single-chamber and mean VP &gt; 21% vs ≤ 21%.

Conclusions

Patients treated with PPMi after HTx show on average low percentage of VP over long-term follow-up. AV block indication and early implantation are associated with a higher percentage of VP. The rate of VP, the timing of PPMi and the use of single vs dual chamber PM do not affect overall prognosis or left ventricular systolic function. Our data may justify implantation of a single-chamber PPM, which bears less complications and procedural time, in the majority of HTx patients needing PPMi.

Incidence of Ventricular Arrhythmias and 1-Year Predictors of Mortality in Patients Treated With Implantable Cardioverter-Defibrillator Undergoing Generator Replacement

Background

When implantable cardioverter defibrillator (ICD) battery is depleted most patients undergo generator replacement (GR) even in the absence of persistent ICD indication. The aim of this study was to assess the incidence of ventricular arrhythmias and the overall prognosis of patients with and without persistent ICD indication undergoing GR. Predictors of 1‐year mortality were also analyzed.

Methods and Results

Patients with structural heart disease implanted with primary prevention ICD undergoing GR were included. Patients were stratified based on the presence/absence of persistent ICD indication (left ventricular ejection fraction ≤35% at the time of GR and/or history of appropriate ICD therapies during the first generator's life). The study included 371 patients (82% male, 40% with ischemic heart disease). One third of patients (n=121) no longer met ICD indication at the time of GR. During a median follow‐up of 34 months after GR patients without persistent ICD indication showed a significantly lower incidence of appropriate ICD shocks (1.9% versus 16.2%, P<0.001) and ICD therapies. 1‐year mortality was also significantly lower in patients without persistent ICD indication (1% versus 8.3%, P=0.009). At multivariable analysis permanent atrial fibrillation, chronic advanced renal impairment, age >80, and persistent ICD indication were found to be significant predictors of 1‐year mortality.

Conclusions

Patients without persistent ICD indication at the time of GR show a low incidence of appropriate ICD therapies after GR. Persistent ICD indication, atrial fibrillation, advanced chronic renal disease, and age >80 are significant predictors of 1‐year mortality. Our findings enlighten the need of performing a comprehensive clinical reevaluation of ICD patients at the time of GR.

232Accessory pathway ablation in adults: estimated additional cancer risk depending on the mapping and ablation strategy

Introduction

Catheter ablation is the treatment of choice for accessory pathways (AP) in high risk patients and it´s usually performed under fluoroscopy guidance (reported X-Ray time:16 -38min).Radiation exposure is associated with an increased incidence of dermatitis,gene defects, cataract and malignancy.3-D mapping systems(EAMS) can reduce fluoroscopy exposure.

Purpose

To evaluate the additional cancer risk throughout life in 2 homogeneous adult populations of high-risk APs treated either with conventional fluoroscopically guided ablation (CFA) or with an EAM- and echocardiography(TEE or ICE)guided minimally fluoroscopic ablation approach (MFA).Methods:  2 Center study, 60 consecutive pts enrolled; 31pts underwent CFA at IRCCS Policlinico san Matteo (Pavia) and 29 pts underwent EAM guided MFA at Klinikum Fuerth between 01/2016 and 09/2019.The age and gender-adjusted cancer risk was calculated following Monte Carlo code,according to Biological Effects of Ionizing Radiation (BEIR VII) empirical risk models. 

Results

The estimated additional cancer risk throughout life gained with a single ablation procedure was significatively different between groups:0.18% in CFA compared to 0.001% in MFA group(P &lt; 0.001).The maximum estimated additional cancer risk for a patient undergoing CFA was 1%.10 out of 29 MFA procedures(35%)were successfully performed with zero fluoroscopy. Conclusions:Our small study demonstrates that an echocardiography/EAM guided approach allows safe AP ablation adding a significantly reduced estimated cancer risk compared to CFA in young adults,a population sensitive to X-ray exposure regarding the stochastic risk of developing malignancies.This finding strongly supports the recommendation for a routine use of EAMS in AP ablations,including appropriate reimbursement.

Results Conventional fluoroscopic approach Minimal fluoroscopic approach p Patient (N) 31 29 n.s. Age (Y) 43.7 ± 14 44.7 ± 17 n.s. Right AP 10 6 n.s. Left Ap 21 23 n.s. Transeptal Access 20 22 n.s. Complications 1 (3%) 0 n.s. DAP (µGy*m2) 15252+/-11132 56.8+/-135.6 0.000 Effective Dose (mSv) 30.35+/-27.7 0.09+/-0.28 0.000. Additional Cancer Risk 0.18% 0.001% &gt;0.001 N, number; Y, years; AP, Accessory Pathway.

48Remote monitoring of Heart Failure patients with a Multisensor ICD Algorithm: value of an alert-based follow-up strategy

Background

The HeartLogic algorithm measures and combines multiple parameters, i.e. heart sounds, intrathoracic impedance, respiration pattern, night heart rate, and patient activity, in a single index. The associated alert has proved to be a sensitive and timely predictor of impending heart failure (HF) decompensation, and the HeartLogic alert condition was shown to identify patients during periods of significantly increased risk of HF events.

Purpose

To report the results of a multicenter experience of remote HF management with HeartLogic algorithm and appraise the value of an alert-based follow-up strategy.

Methods

The HeartLogic feature was activated in 104 patients (76 male, 71 ± 10 years, left ventricular ejection fraction 29 ± 7%). All patients were followed according to a standardized protocol that included remote data reviews and patient phone contacts every month and at the time of HeartLogic alerts. In-office visits were performed every 6 months or when deemed necessary.

Results

During a median follow-up of 13[11-18] months, centers performed remote follow-up at the time of 1284 scheduled monthly transmissions (10.5 per pt-year) and 100 HeartLogic alerts (0.82 alerts/pt-year). The mean delay from alert to the next monthly remote data review was 14 ± 8 days. Overall, the patient time in the alert state (i.e. HeartLogic index above the threshold) was 14% of the total observation period. HF events requiring active clinical actions were detected at the time of 11 (0.9%) monthly remote data reviews and at 43 (43%, p &lt; 0.001) HeartLogic alerts. Moderate to severe symptoms of HF were reported during 2% of remote visits when the patient was out of HeartLogic alert condition and during 15% of remote visits performed in alert condition (p &lt; 0.001). Out of 100 alerts, 17 required an in-office visit and 5 a hospitalization to manage the clinical condition. Overall, 282 scheduled and 56 unscheduled in-office visits were performed during follow-up. Any HF sign (i.e. S3 gallop, rales, jugular venous distension, edema) was detected during 18% of in-office visits when the patient was out of HeartLogic alert condition and during 34% of visits performed in alert condition (p = 0.002).

Conclusions

HeartLogic alerts are frequently associated with relevant actionable HF events. Events are detected earlier and the volume of alert-driven remote follow-ups is limited when compared with a monthly remote follow-up scheme. The probability of detecting common signs and symptoms of HF at regular remote or in-office assessment is extremely low when the patient is out of HeartLogic alert state. These results support the adoption of an alert-based follow-up strategy.

P523Incidence of anti tachycardia therapies and mortality at one and two years in patients with and without persistent ICD indication at the time of generator replacement

BACKGROUND ICD implantation with or without resynchronization is an established therapy for the prevention of sudden cardiac death in patients with LV dysfunction. However, when elective replacement interval (ERI) approaches most patients undergo generator replacement (GR) even in the absence of persistent indication to ICD therapy- Moreover, at the time of GR patients are usually older and with more comorbidities as compared to the time of first implantation.

AIM The aim of our work was to evaluate the rate and predictors of mortality and to analyze.the incidence of appropriate ICD therapies after GR.

METHODS Our registry includes 323 patients with structural heart disease (SHD) implanted with ICD in primary prevention who underwent GR. Our population was stratified based on the presence or absence of persistent indication to ICD at the time of GR, which was defined as: LVEF ≤ 35% and/o history of appropriate ICD therapies during the first generator"s life. In each group the incidence of appropriate ICD therapies after GR, 1 and 2 years mortality after GR and multivariate predictors of 1 year mortality. Were analyzed. Comparisons between categorical variables were made using χ2 or Fisher Exact test when required and continuous variables were compared using Mann Whitney test.  Kaplan-Meier curves with Log Rank test were used to investigate 1 and 2 years mortality.

RESULTS In our population, 81% were male, 41% had ischemic heart disease, 60% had CRT-D. Median LVEF at the time of first implantation was 30%  (25-35), whereas at the time of GR was 35% (25-45); median age at GR was 64 (56-73) years. Notably 33.6% of our population no longer met ICD indication at the time of GR; this subgroup showed a significantly lower mortality at one and two years as compared to patients with persistent ICD indication: 1% vs 9% and 2.1% vs 13.5% respectively (figure 1 and 2). At multivariable analysis permanent AF (HR: 3.6; 95% CI 1.9-8.6) chronic renal disease (HR 4; 2.3-8.9), and persistent ICD indication  were independent predictors of 1-year mortality. When survival analysis was limited to patients implanted with single-chamber and dual-chamber devices only AF an renal insufficiency remained significantly predictors of mortality. Nevertheless, in this subgroup, the absence of persistent indication was associated with a significantly lower rate of appropriate ICD therapies after GR (0% vs 14.8%, p = 0.02). 

CONCLUSION The absence of persistent indication at the time of generator replacement was associated with a significantly better prognosis and a lower incidence of appropriate therapies after GR. Atrial fibrillation, renal insufficiency and persistent ICD indication significantly predicted 1 year mortality in our population. Our data suggest the importance of an arrhythmic vs. non-arrhythmic risk evaluation in the individual patient at the time of ICD generator replacement

Abstract Figure.

P1453Feasibility and safety of a minimal fluoroscopy approach, aiming to ALARA strategy, compared to conventional approach in a population of adult patients with high risk accessory pathways

Funding Acknowledgements

None

Introduction

Catheter ablation is the treatment of choice for accessory pathways (AP) in high risk patients.Traditionally fluoroscopy has been the primary tool for visualizing catheter position and stability, however it has been shown that 3D electro-anatomic mapping systems (3D EAMS) can significantly reduce and even eliminate fluoroscopy exposure during catheter ablation, thus reducing the stochastic risk of malignancies.

Purpose

aim of our study is to assess that an ablation strategy using 3D EAMS with limited or no fluoroscopy, rigorous set-up of the X-ray equipment and intracardiac or transesofageal (TEE)echo to guide the transeptal puncture has the same degree of safety and effectiveness in ablating APs as the conventional fluoroscopic approach (CFA), and can be adopted for both right and left sided APs in the adult population,reducing the effective doses.

Methods

our retrospective analysis included 60 consecutive-prospective enrolled adult patients with high-risk APs treated either with a CFA in IRCCS Policlinico San Matteo (Pavia) or with a 3 EAMS guided minimally fluoroscopic approach (MFA) in Klinikum Fuerth (Fuerth) between 01/2016 and 09/2019. 

Results

the 2 groups were homogeneous and comparable for age,sex and numbers of right/left-sided SP. In the MFA group we demonstrated the safety and feasibility of a principally 3D EAMS guided ablation approach, having the same rate of acute ablation success,while obtaining a statistically different fluoroscopy exposure time (P &lt;0.000), dosis-area product (P&lt; 0.000) and effective dosis (P &lt; 0.000) compared to the CFA group. (Table)

Conclusions

the radiation exposure risk is cumulative and lifelong. We demonstrated that to adopt a MFA increasing the use of 3D EAMS, fluoro optminization and  of TEE guided transeptal is feasible and safe forAPs ablation in adults, which will benefit of a lower or even absent fluoroscopic exposure while having the same degree of safety and efficacy of a CFA.

Results Conventional Fluoroscopic Approach Minimal fluoroscopic approach P Patient (N) 31 29 n.s. Right AP 10 6 n.s. Left AP 21 23 n.s. Acute Efficacy 27 (87%) 28 (96.6%) n.s. Complication 1 (3%) 0 n.s. Fluoroscopy Time (min) 43+/-32 1.8+/-3.8 0.000 DAP (microGray*m2) 15252+/-11132 56.8+/-135.6 0.000 Effective Dosis (mSv) 30.35+/-27.7 0.09+/-0.28 0.000 AP, accessory pathway; min, minutes.

855Performance of a multisensor icd algorithm in heart failure patient management

Funding Acknowledgements

No funding

Background

The HeartLogic index combines data from multiple implantable cardioverter-defibrillator (ICD)-based sensors and has proved to be a sensitive and timely predictor of impending heart failure (HF) decompensation.

Purpose

To describe a multicenter experience of remote HF management of patients who received a HeartLogic-enabled ICD or cardiac resynchronization therapy ICD (CRT-D).

Methods

The HeartLogic feature was activated in 104 patients (76 male, 71 ± 10 years, left ventricular ejection fraction 29 ± 7%). In accordance with a standardized follow-up protocol, remote data reviews and patient phone contacts were performed monthly and at the time of HeartLogic alerts (when the index crossed the nominal threshold value of 16), to assess the patient decompensation status. In-office visits were performed every 6 months or when deemed necessary.

Results

During a median follow-up of 13[11-18] months, 100 HeartLogic alerts were reported (0.82 alerts/pt-year) in 53 patients. 60 HeartLogic alerts were judged clinically meaningful (i.e. associated with worsening of HF or resulted in active clinical actions). Specifically, multiple associated conditions were reported: 45 (75%) symptoms or signs of clinical deterioration of HF, 13 (22%) discontinuations or reductions of prescribed HF therapy, 11 (18%) declines in CRT percentage (with or without new onset atrial fibrillation), 8 (13%) recurrences of previous HF events. For 48 out of 60 alerts the clinician was not previously aware of the condition. Of these, 43 alerts triggered multiple clinical actions. Alert-triggered actions were: 30 (70%) diuretic dosage increases, 15 (35%) other drug adjustments, 6 (14%) HF hospitalizations, 3 (7%) device reprogramming/revisions, 1 (2%) cardioversion, 1 (2%) patient education on therapy adherence. Out of 40 non-clinically meaningful alerts (0.33 alerts/pt-year), 8 (20%) were associated with non-HF therapy changes or interventions, 3 (8%) with pulmonary events, 29 (72%) remained unexplained. The overall number of HF hospitalizations was 16 (rate 0.13 hospitalizations/pt-year). Five HF hospitalizations were not preceded by HeartLogic alert (0.04 hospitalizations/pt-year).

Conclusions

The HeartLogic index provided clinically meaningful information and allowed to remotely identify relevant HF related clinical conditions, with a low rate of unexplained detections and undetected HF events. In this experience, remote monitoring using HeartLogic alerts allowed to drive HF care and take effective clinical actions.

Prospective evaluation of the multisensor HeartLogic algorithm for heart failure monitoring

Background

The HeartLogic algorithm measures data from multiple implantable cardioverter‐defibrillator‐based sensors and combines them into a single index. The associated alert has proved to be a sensitive and timely predictor of impending heart failure (HF) decompensation.

Hypothesis

We describe a multicenter experience of remote HF management by means of HeartLogic and appraise the value of an alert‐based follow‐up strategy.

Methods

The alert was activated in 104 patients. All patients were followed up according to a standardized protocol that included remote data reviews and patient phone contacts every month and at the time of alerts. In‐office examinations were performed every 6 months or when deemed necessary.

Results

During a median follow‐up of 13 (10–16) months, the overall number of HF hospitalizations was 16 (rate 0.15 hospitalizations/patient‐year) and 100 alerts were reported in 53 patients. Sixty alerts were judged clinically meaningful, and were associated with multiple HF‐related conditions. In 48 of the 60 alerts, the clinician was not previously aware of the condition. Of these 48 alerts, 43 triggered clinical actions. The rate of alerts judged nonclinically meaningful was 0.37/patient‐year, and the rate of hospitalizations not associated with an alert was 0.05/patient‐year. Centers performed remote follow‐up assessments of 1113 scheduled monthly transmissions (10.3/patient‐year) and 100 alerts (0.93/patient‐year). Monthly remote data review allowed to detect 11 (1%) HF events requiring clinical actions (vs 43% actionable alerts, P < .001).

Conclusions

HeartLogic allowed relevant HF‐related clinical conditions to be identified remotely and enabled effective clinical actions to be taken; the rates of unexplained alerts and undetected HF events were low. An alert‐based management strategy seemed more efficient than a scheduled monthly remote follow‐up scheme.

P5640How to decide to implant an ICD in out-of-hospital cardiac arrest survivors with bad neurological outcome. CPC is an option?

Background

According to the European Society of Cardiology guidelines secondary prevention ICD implantation is a class I indication only for those patients with an estimated survival >1 year with a good functional status. However, it is not specified how to assess the functional status and its evaluation could be quite difficult in the case of Out-of-Hospital Cardiac Arrest (OHCA) survivors. Cerebral Performance Category (CPC) scale is the most widespread scale to define the neurological and functional outcome, but it is not known if it can be used to guide ICD implantation.

Purpose

To evaluate whether the presence of a bad neurological outcome (CPC >2) in OHCA survivors at discharged could be used as a prognostic index in order to evaluate the implantation of an ICD.

Methods

We considered all the patients enrolled in the Cardiac Arrest Registry of our Province (55ehz746.0583 inhabitants in northern Italy) from the 1 October 2014 to the 31 January 2018 presenting a CPC >2 at discharge. We evaluated the survival and the neurological status variation at 1-year.

Results

In the study period CPR was attempted in 1565 confirmed OHCA (60.2% males, 73.4±15.8 years). Of these, 119 (7.6%) were discharged and 26 of them (21.8%) showed a CPC more than 2 (13 CPC = 3, 11 CPC = 4 and 2 CPC A). 1-year survival of CPC>2 patients was significantly lower than those with a CPC≤2 (46.1% vs 92.5% p<0.001). Only 12/26 patients discharged with a CPC >2 survived at 1 year; a good cerebral performance (CPC 1) was recovered in 2 of them, whilst a moderate cerebral disability (CPC 2) was present in 1 of them. A severe cerebral disability (CPC 3 or 4) persisted in the other 9 patients. The neurological prognosis of patients based on CPC at hospital discharge is presented in Figure 1.

Figure 1

Conclusions

Our results highlight that 1-year survival is quite low in patients with a CPC >2 at discharge and an improvement in cerebral performance occur in a minority of them. The prognosis of the patients was very variable and unpredictable for all the CPC scale values at hospital discharge. This evidence suggest that an ICD implantation should carefully evaluated in this kind of patients and a clinical and neurological re-evaluation can be reasonable some time after the event to decide if implant an ICD.

P2825ICD implantation in secondary prevention after an out-of-hospital cardiac arrest. Does age really matter?

Background

The implantation of an implantable cardioverter defibrillator (ICD) in secondary prevention is a class I indication for patients with an estimated survival more than 1 year with a good functional status. However, in the elderly population, it is often difficult to estimate the expected survival, especially after an acute event such as an out-of-hospital cardiac arrest (OHCA).

Purpose

To evaluate 1-year survival after OHCA of patients older than 80 compared to those younger than 80.

Methods

We considered all the patients who suffered an OHCA in our Province (55ehz748.1135 inhabitants in northern Italy) from October 1st 2014 to November 30th 2017 stratified in two groups accordingly to their age at the moment of OHCA: elderly group (≥80 years old) and non-elderly group (<80 years old).

Results

In the period analysis resuscitation was attempted in 1464 OHCA patients: 632 of the elderly group (mean age of 86.4±4.4 years) and 832 of the non-elderly group (mean age of 63.4±13.8 years). The two groups were different at baseline. In the non-elderly group there were more males (74.5% vs 42.4%, p<0.001), more cases of medical etiology (95.9% vs 91.2%, p<0.001), a higher rate of bystander CPR (39.4% vs 23.4%, p<0.001) and more shockable rhythms at presentation (25.5% vs 7.9%, p<0.001), whilst a home location of the event was more frequent in the elderly group (81.3% vs 77%, p=0.048). No differences were found regarding both the percentage of not witnessed cardiac arrest (27.5% in elderly and 26% in non-elderly, p=0.57) and the time of EMS arrival (11:36 mins in elderly and 11:23 mins in young, p=0.64). Non-elderly patients showed a significantly higher rate of survival both to hospital admission (25.2% vs 6.8%, p<0.001), to hospital discharge (12.1% vs 1.7%, p<0.001) and at 1 year after the event (10.2% vs 1.6%, p<0.001, Figure 1 - left) as compared to older ones. However, when considering only those patients discharged alive we found a non-significant difference in one-year survival (84.2% vs 90.9%, p=0.64, Figure 1 – right).

Conclusions

Elderly patients have a worst prognosis in the acute phase after an OHCA. However, after hospital discharge, older and younger patients showed a similar 1-year survival. This result highlights how age should not be considered alone to decide whether an ICD in secondary prevention could be indicated or not in older OHCA survivors.

6118Mid- and long-term percentage of ventricular pacing in patients implanted with a pacemaker after a transcatheter aortic valve replacement procedure: potential clinical implications

Background

Cardiac conduction disturbances frequently occur following transcatheter aortic valve replacement (TAVR). As this procedure is getting more and more common, more research efforts should focus on post procedural rhythm disturbances and their evolution over time

Purpose

To evaluate the percentage of pacing in patients who underwent a TAVR procedure and developed a conduction disturbance requiring a transvenous pacemaker (PM) implantation

Methods

We considered all the patients who underwent a TAVR procedure between march 2009 and november 2018 in our centre. Patients implanted with a PM or an ICD before the TAVR procedure or 30 days after the TAVR were not considered eligible for our analysis, because likely not related to TAVR. The percentage of effective right ventricular pacing was assessed both at mid- and long-term follow-up

Results

265 patients underwent TAVR in the study period (45% males, 81±6 years). 20 patients already had a PM and were excluded. 39 of the 245 patients (16%) were implanted with a PM after TAVR, 26 of them were implanted within 30 days (median time TAVR-PM implant: 8±7 days). The rate of PM implant within 30 days after TAVR was 8% (20/246) for patients implanted with an Edward Sapien valve, 25% (4/16) for patients with an Evolute Pro valve and 66% (2/3) in patients with a Lotus Edge valve. The indication for PM implant was a permanent 3rd degree A-V block in 12 patients, a paroxysmal A-V block in 4, a bifascicular A-V block with an infra-hisian disease in 5, a II degree Mobitz II A-V block in 2, an atrial fibrillation with slow A-V conduction in 2 and a 2:1 A-V block with infra-hisian disease in 1. The first follow-up after the PM implantation was available in 24 patients (mean 78±87 days after PM implant) and the second in 15 patients (372±267 days after PM implant). The patients were divided into two groups based on the presence/absence of permanent 3rd degree AV block at the time of implantation. At the first follow-up the percentage of pacing was significantly higher in patients implanted with vs. without a permanent 3rd degree AV block (98.5% vs 11%, p<0.001). Notably, in none of the patients without a permanent 3rd AV block at baseline conduction disturbances progressed toward a permanent AV block during long-term follow-up. Accordingly, at the second follow-up patients without permanent 3rd AV block at baseline showed a significantly lower percentage of pacing (1% vs 100%; p<0.01)

Conclusion

Patients implanted with a PM after TAVR in the absence of a permanent 3rd AV block have a very low likelihood of progression to a permanent AV conduction disturbance and show a negligible percentage of pacing during follow-up. Our results may impact the choice of the correct timing of PM implantation after TAVR and the potential indication for a leadless PM.

Preliminary experience with the multisensor HeartLogic algorithm for heart failure monitoring: a retrospective case series report

Aims

In the Multisensor Chronic Evaluation in Ambulatory Heart Failure Patients study, a novel algorithm for heart failure (HF) monitoring was implemented. The HeartLogic (Boston Scientific) index combines data from multiple implantable cardioverter defibrillator (ICD)‐based sensors and has proved to be a sensitive and timely predictor of impending HF decompensation. The remote monitoring of HF patients by means of HeartLogic has never been described in clinical practice. We report post‐implantation data collected from sensors, the combined index, and their association with clinical events during follow‐up in a group of patients who received a HeartLogic‐enabled device in clinical practice.

Methods and results

Patients with ICD and cardiac resynchronization therapy ICD were remotely monitored. In December 2017, the HeartLogic feature was activated on the remote monitoring platform, and multiple ICD‐based sensor data collected since device implantation were made available: HeartLogic index, heart rate, heart sounds, thoracic impedance, respiration, and activity. Their association with clinical events was retrospectively analysed. Data from 58 patients were analysed. During a mean follow‐up of 5 ± 3 months, the HeartLogic index crossed the threshold value (set by default to 16) 24 times (over 24 person‐years, 0.99 alerts/patient‐year) in 16 patients. HeartLogic alerts preceded five HF hospitalizations and five unplanned in‐office visits for HF. Symptoms or signs of HF were also reported at the time of five scheduled visits. The median early warning time and the time spent in alert were longer in the case of hospitalizations than in the case of minor events of clinical deterioration of HF. HeartLogic contributing sensors detected changes in heart sound amplitude (increased third sound and decreased first sound) in all cases of alerts. Patients with HeartLogic alerts during the observation period had higher New York Heart Association class (P = 0.025) and lower ejection fraction (P = 0.016) at the time of activation.

Conclusions

Our retrospective analysis indicates that the HeartLogic algorithm might be useful to detect gradual worsening of HF and to stratify risk of HF decompensation.

The economic impact of battery longevity in implantable cardioverter-defibrillators for cardiac resynchronization therapy: the hospital and healthcare system perspectives

Aims

Patients receiving cardiac resynchronization therapy defibrillators (CRT-Ds) are likely to undergo one or more device replacements, mainly for battery depletion. We assessed the economic impact of battery depletion on the overall cost of CRT-D treatment from the perspectives of the healthcare system and the hospital. We also compared devices of different generations and from different manufacturers in terms of therapy cost.

Methods and results

We analysed data on 1792 CRT-Ds implanted in 1399 patients in 9 Italian centres. We calculated the replacement probability and the total therapy cost over 6 years, stratified by device generation and manufacturer. Public tariffs from diagnosis-related groups were used together with device prices and hospitalization costs. Generators were from 3 manufacturers: Boston Scientific (667, 37%), Medtronic (973, 54%), and St Jude Medical (152, 9%). The replacement probability at 6 years was 83 and 68% for earlier- and recent-generation devices, respectively. The need for replacement increased total therapy costs by more than 50% over the initial implantation cost for hospitals and by more than 30% for healthcare system. The improved longevity of recent-generation CRT-Ds reduced the therapy cost by ∼6% in both perspectives. Among recent-generation CRT-Ds, the replacement probability of devices from different manufacturers ranged from 12 to 70%. Consequently, the maximum difference in therapy cost between manufacturers was 40% for hospitals and 19% for the healthcare system.

Conclusions

Differences in CRT-D longevity strongly affect the overall therapy cost. While the use of recent-generation devices has reduced the cost, significant differences exist among currently available systems.

Submammary device implantation. Good long-term performance and better patients' satisfaction. A single-center experience

INTRODUCTION

Device related distress negatively affects the quality of life of cardiac device recipients mostly of women. A submammary approach has been proposed to reduce the physical impact of the implantation. Our aim was to assess the safety of this approach and to evaluate the patients' acceptance of the device.

METHODS

We enrolled 42 patients who underwent a submammary device. The primary endpoint was the need for implant revision that was assessed in the study group compared with the overall control group of 72 standard cardiac device recipients (29 females and 43 males)and with the female group (29 females of controls). In the female population (42 women of the submammary group and 29 of controls) patients' acceptance was calculated with the Florida Patient Acceptance Survey (FPAS).

RESULTS

The rate of implant revision was similar in the two groups and the revision-free survival was comparable with a median follow-up of about six years (Log rank test p=0.949). Similar results were found when considering only the female population. Patients' acceptance was greater in the submammary group [total FPAS 85 (95%CI 83-86) vs 74.5 (95%CI 70.2-77.3) p<0,001] and a strongly significant superiority of the submammary group was found regarding body image concerns [10 (95%CI 10-10) vs 8 (95%CI 8-8) p<0.001) and device related distress [23 (95%CI 22-23) vs 1 (95%CI 1-1) p<0.001].

CONCLUSIONS

Submammary device implantation is safe and more accepted than standard approach. Our results should encourage cardiologists to suggest this approach to their patients for a better acceptance of the therapy.

Longevity of implantable cardioverter-defibrillators for cardiac resynchronization therapy in current clinical practice: an analysis according to influencing factors, device generation, and manufacturer

Aims

Device replacement at the time of battery depletion of implantable cardioverter-defibrillators (ICDs) may carry a considerable risk of complications and engenders costs for healthcare systems. Therefore, ICD device longevity is extremely important both from a clinical and economic standpoint. Cardiac resynchronization therapy defibrillators (CRT-D) battery longevity is shorter than ICDs. We determined the rate of replacements for battery depletion and we identified possible determinants of early depletion in a series of patients who had undergone implantation of CRT-D devices.

Methods and results

We retrieved data on 1726 consecutive CRT-D systems implanted from January 2008 to March 2010 in nine centres. Five years after a successful CRT-D implantation procedure, 46% of devices were replaced due to battery depletion. The time to device replacement for battery depletion differed considerably among currently available CRT-D systems from different manufacturers, with rates of batteries still in service at 5 years ranging from 52 to 88% (log-rank test, P < 0.001). Left ventricular lead output and unipolar pacing configuration were independent determinants of early depletion [hazard ratio (HR): 1.96; 95% 95% confidence interval (CI): 1.57–2.46; P < 0.001 and HR: 1.58, 95% CI: 1.25–2.01; P < 0.001, respectively]. The implantation of a recent-generation device (HR: 0.57; 95% CI: 0.45–0.72; P < 0.001), the battery chemistry and the CRT-D manufacturer (HR: 0.64; 95% CI: 0.47–0.89; P = 0.008) were additional factors associated with replacement for battery depletion.

Conclusion

The device longevity at 5 years was 54%. High left ventricular lead output and unipolar pacing configuration were associated with early battery depletion, while recent-generation CRT-Ds displayed better longevity. Significant differences emerged among currently available CRT-D systems from different manufacturers.

Anatomical mapping for atrial fibrillation ablation: a head-to-head comparison of ultrasound-assisted reconstruction versus fast anatomical mapping

BACKGROUND

Accuracy in left atrial (LA) anatomical reconstruction is crucial to the safe and effective performance of catheter ablation of atrial fibrillation (AF). The aim of this study was to evaluate the accuracy of LA reconstruction performed with intracardiac echocardiography (ICE) as compared to fast anatomical mapping (FAM) both integrated in the CARTO mapping system (Biosense Webster, Diamond Bar, CA, USA).

METHODS

A multislice computed tomography (MSCT) was preacquired from 29 patients with AF who underwent catheter ablation and 3D-LA geometry was reconstructed using both ICE and FAM separately. The accuracy of the LA anatomical definition was evaluated by comparing LA volumes, LA and pulmonary vein (PV) diameters obtained using ICE and FAM versus MSCT (gold standard).

RESULTS

Anterior-posterior and superior-inferior LA diameters were shorter in ICE versus MSCT (32 ± 10 vs 46 ± 9 mm and 48 ± 7 vs 53 ± 7 mm, P < 0.01) but similar in FAM versus MSCT (45 ± 9 vs 46 ± 9 mm and 52 ± 10 vs 53 ± 7 mm). Latero-septal LA diameter was similar in ICE versus MSCT (63 ± 11 vs 63 ± 9 mm) but larger in FAM versus MSCT (69 ± 9 vs 63 ± 9 mm, P < 0.001). LA volume was lower in ICE versus MSCT (73 ± 30 mL vs 116 ± 45 mL, P < 0.0001) and slightly larger in FAM versus MSCT (132 ± 45 vs 116 ± 45 mL, P = 0.06). PV diameters were similar in FAM versus MSCT but significantly underestimated with ICE.

CONCLUSIONS

Overall accuracy in the LA and PV anatomical reconstruction was found to be superior with FAM compared to ICE-guided approach. ICE resulted in a significant underestimate of both LA and PV dimensions, while FAM slightly overestimated LA geometry.

Women with nonischemic cardiomyopathy have a favorable prognosis and a better left ventricular remodeling than men after cardiac resynchronization therapy

AIMS

Cardiac resynchronization therapy (CRT) is a well established therapy in heart failure patients who are on optimal medical therapy and have reduced left ventricular ejection fraction (LVEF) and wide QRS complexes. Although women and patients with nonischemic cardiomyopathy are under-represented in CRT trials and registries, there is evidence that these two groups of patients can benefit more from CRT. The aim of our analysis was to investigate the impact of female sex on mortality in a population that included a high percentage of patients (61%) with nonischemic cardiomyopathy.

METHODS

We analyzed data on 507 consecutive patients (20% women) who received CRT at two Italian Heart Transplant centers and were followed up for a maximum of 48 months.

RESULTS

After multivariate adjustment, women showed a trend toward better survival with regard to all-cause mortality [hazard ratio (HR) 0.32, confidence interval (CI) 0.10-1.04; P = 0.059]. However, this benefit was limited to nonischemic patients with regard to all-cause mortality (HR 0.20, CI 0.05-0.87, P = 0.032) and cardiovascular mortality (HR 0.14, CI 0.02-1.05, P = 0.056).

CONCLUSION

Female CRT recipients, at mid-term, have a favorable prognosis than male patients and this benefit appears to be more evident in nonischemic patients. Thus, we strongly believe that the apparent under-utilization of CRT in females is an anomaly that should be corrected.

Vagal reflexes following an exercise stress test: a simple clinical tool for gene-specific risk stratification in the long QT syndrome

OBJECTIVES

The study assessed whether heart rate (HR) reduction following an exercise stress test (ExStrT), an easily quantifiable marker of vagal reflexes, might identify high- and low-risk long QT syndrome (LQTS) type 1 (LQT1) patients.

BACKGROUND

Identification of LQTS patients more likely to be symptomatic remains elusive. We have previously shown that depressed baroreflex sensitivity, an established marker of reduced vagal reflexes, predicts low probability of symptoms among LQT1.

METHODS

We studied 169 LQTS genotype-positive patients < 50 years of age who performed an ExStrT with the same protocol, on and off β-blockers including 47 South African LQT1 patients all harboring the KCNQ1-A341V mutation and 122 Italian LQTS patients with impaired (I(Ks)-, 66 LQT1) or normal (I(Ks)+, 50 LQT2 and 6 LQT3) I(Ks) current.

RESULTS

Despite similar maximal HR and workload, by the first minute after cessation of exercise the symptomatic patients in both I(Ks)- groups had a greater HR reduction compared with the asymptomatic (19 ± 7 beats/min vs. 13 ± 5 beats/min and 27 ± 10 beats/min vs. 20 ± 8 beats/min, both p = 0.009). By contrast, there was no difference between the I(Ks)+ symptomatic and asymptomatic patients (23 ± 9 beats/min vs. 26 ± 9 beats/min, p = 0.47). LQT1 patients in the upper tertile for HR reduction had a higher risk of being symptomatic (odds ratio: 3.28, 95% confidence interval: 1.3 to 8.3, p = 0.012).

CONCLUSIONS

HR reduction following exercise identifies LQT1 patients at high or low arrhythmic risk, independently of β-blocker therapy, and contributes to risk stratification. Intense exercise training, which potentiates vagal reflexes, should probably be avoided by LQT1 patients.

Pharmacological therapy following catheter ablation of atrial fibrillation

Catheter ablation has been proven to be an effective treatment for patients with drug-resistant atrial fibrillation. Nevertheless its efficacy is limited to 60-80% of patients in different studies. Whether the use of pharmacological therapy after catheter ablation of atrial fibrillation might increase the procedural success rate is still a matter of debate. There is general agreement that antiarrhythmic drugs (AADs) are useful in the management of arrhythmias occurring in the very early period after catheter ablation (blanking period). On the contrary, limited data are available on the efficacy of AADs over a longer period. Some patients remain free of arrhythmia recurrences by the use of AADs that were ineffective before catheter ablation: whether this latter situation is to be considered a partial success of catheter ablation or a treatment failure, thus demanding a redo procedure, is still an open question. Some studies have also investigated the role of non-AADs [angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers, statins and corticosteroids] in preventing atrial fibrillation recurrences after catheter ablation, reporting conflicting results. Whereas there is a general consensus on the use of anticoagulation therapy in the first phase after catheter ablation, no definite data are available on the proper long-term management of anticoagulation therapy after catheter ablation. This review focuses on the still open issue of what is the optimal pharmacological treatment of patients after catheter ablation of atrial fibrillation.

Fast-slow and slow-slow form of atrioventricular nodal reentrant tachycardia sustained by the same reentrant circuit: a case report

It has been suggested that a reentrant circuit confined to the posterior extensions of the atrioventricular node underlies both fast-slow and slow-slow types of atrioventricular nodal reentrant tachycardia (AVNRT). According to this hypothesis the fast-slow reentrant circuit would be formed by two slow pathways, located in the rightward and leftward posterior extension of the atrioventricular node. Thus, the fast pathway would act as a bystander with respect to the reentrant circuit. We describe the case of a 40-year-old woman with several episodes of palpitations unresponsive to antiarrhythmic drugs. The ECG during symptoms showed a narrow QRS tachycardia with a long ventriculo-atrial interval and a negative P wave in the inferior leads. Electrophysiological study showed the inducibility of a slow-slow AVNRT which rapidly shifted to a fast-slow AVNRT without any change in the duration of the tachycardia cycle. Our observation is in agreement with the hypothesis that the fast-slow reentrant circuit consists of two slow pathways with the fast pathway acting as a bystander.

Periodic conduction and 2:1 block from the left atrium to the pulmonary vein during radiofrequency ablation

Paroxysmal atrial fibrillation is often initiated by foci in the pulmonary veins (PVs); the junction between the PVs and the left atrium (LA) has become the target of radiofrequency (RF) ablation performed to isolate the PVs. Ectopic atrial beats originating from the PVs propagate to the LA with a characteristically long conduction time, often with a conduction delay or block within the PV or at the PV-LA junction. However, details about the conduction properties within the PVs and across the PV-LA junction are still scanty. We report a unique case of LA-PV decremental conduction caused by RF applications. New insights into the electroanatomical characteristics of the PV-LA junction are provided. The present report demonstrates, for the first time in humans, that decremental conduction may be related to the progressive damage of the conducting myocardial bundle due to RF energy applications.