Heart size disparity drives sex-specific response to cardiac resynchronization therapy: a post-hoc analysis of the MORE-MPP CRT trial

Background

Studies have reported that female sex predicts superior cardiac resynchronization therapy (CRT) response. One theory is that this association is related to smaller female heart size, thus increased "relative dyssynchrony" at given QRS durations (QRSd).

Objective

To investigate the mechanisms of sex-specific CRT response relating to heart size, relative dyssynchrony, cardiomyopathy type, QRS morphology, and other patient characteristics.

Methods

A post-hoc analysis of the MORE-CRT MPP trial (n=3739, 28% female), with a sub-group analysis of patients with non-ischaemic cardiomyopathy (NICM) and left bundle branch block (LBBB) (n=1308, 41% female) to control for confounding characteristics. A multivariable analysis examined predictors of response to 6 months of conventional CRT, including sex and relative dyssynchrony, measured by QRSd/LVEDV (left ventricular end-diastolic volume).

Results

Females had a higher CRT response rate than males (70.1% vs. 56.8%, p<0.0001). Subgroup analysis: Regression analysis of the NICM LBBB subgroup identified QRSd/LVEDV, but not sex, as a modifier of CRT response (p<0.0039). QRSd/LVEDV was significantly higher in females (0.919) versus males (0.708, p<0.001). CRT response was 78% for female patients with QRSd/LVEDV>median value, compared to 68% < median value (p=0.012). Association between CRT response and QRSd/LVEDV was strongest at QRSd<150ms.

Conclusions

In the NICM LBBB population, increased relative dyssynchrony in females, who have smaller heart sizes than their male counterparts, is a driver of sex-specific CRT response, particularly at QRSd <150ms. Females may benefit from CRT at a QRSd <130ms, opening the debate on whether sex-specific QRSd cut-offs or QRS/LVEDV measurement should be incorporated into clinical guidelines.

Electrocardiographic findings in patients with arrhythmogenic cardiomyopathy and right bundle branch block ventricular tachycardia

AIMS

Little is known about patients with right bundle branch block (RBBB)-ventricular tachycardia (VT) and arrhythmogenic cardiomyopathy (ACM). Our aims were: (i) to describe electrocardiogram (ECG) characteristics of sinus rhythm (SR) and VT; (ii) to correlate SR with RBBB-VT ECGs; and (iii) to compare VT ECGs with electro-anatomic mapping (EAM) data.

METHODS AND RESULTS

From the European Survey on ACM, 70 patients with spontaneous RBBB-VT were included. Putative left ventricular (LV) sites of origin (SOOs) were estimated with a VT-axis-derived methodology and confirmed by EAM data when available.  Overall, 49 (70%) patients met definite Task Force Criteria. Low QRS voltage predominated in lateral leads (n = 37, 55%), but QRS fragmentation was more frequent in inferior leads (n = 15, 23%). T-wave inversion (TWI) was equally frequent in inferior (n = 28, 42%) and lateral (n = 27, 40%) leads. TWI in inferior leads was associated with reduced LV ejection fraction (LVEF; 46 ± 10 vs. 53 ± 8, P = 0.02). Regarding SOOs, the inferior wall harboured 31 (46%) SOOs, followed by the lateral wall (n = 17, 25%), the anterior wall (n = 15, 22%), and the septum (n = 4, 6%). EAM data were available for 16 patients and showed good concordance with the putative SOOs. In all patients with superior-axis RBBB-VT who underwent endo-epicardial VT activation mapping, VT originated from the LV.

CONCLUSIONS

In patients with ACM and RBBB-VT, RBBB-VTs originated mainly from the inferior and lateral LV walls. SR depolarization and repolarization abnormalities were frequent and associated with underlying variants.

Association between atrial fibrillation and cardiac implantable defibrillator detected heart failure status

Funding Acknowledgements

Type of funding sources: None.

Background

In heart failure (HF) patients, atrial fibrillation (AF) is a common comorbidity and is associated with a worse prognosis. Implantable defibrillator (ICD) diagnostics allow continuous monitoring of atrial high-rate events (AHRE), as a surrogate of AF, and are equipped with algorithms for HF monitoring. We evaluated the association between the values of the multisensor HF HeartLogic Index and the incidence of AF, and assessed the performance of the Index in detecting follow-up periods of significantly increased AF risk.

Methods

The HeartLogic feature was activated in 568 ICD patients. The median follow-up was 25 months [25th–75th percentile: 15-35]. The HeartLogic algorithm calculates a daily HF index and identifies periods IN the alert state on the basis of a configurable threshold. The endpoints were: daily AF burden of ≥5 minutes, ≥6 hours and ≥23 hours.

Results

The HeartLogic index crossed the threshold value 1200 times (0.71 alerts/patient-year). The time IN the alert state was 13% of the total observation period. During the observation period, an AF burden of ≥5 minutes/day was documented in 183 (32%) patients, ≥6 hours/day in 118 (21%) patients, and ≥23 hours/day in 89 (16%). On using a time-dependent Cox model, the weekly time IN the alert state was independently associated with an AF burden of ≥5 minutes/day (HR:1.95, 95%CI:1.22-3.13, p=0.005), ≥6 hours/day (HR:2.66, 95%CI:1.60-4.44, p&lt;0.001), and ≥23 hours/day (HR:3.32, 95%CI:1.83-6.02, p&lt;0.001), after correction for baseline confounders. Comparison of the episode rates in the IN-alert state with those in the OUT-of-alert state yielded HRs ranging from 1.57 to 3.11 for AF burden from ≥5 minutes to ≥23 hours.

Conclusions

The HeartLogic alert state was independently associated with AF occurrence. The intervals of time defined by the algorithm as periods of increased risk of HF allow risk stratification of AF according to various thresholds of daily burden.

Improvement in electrical synchrony during bi-ventricular vs. left ventricular pacing with dynamic atrioventricular delays may be predicted by conduction times

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Abbott

Introduction

Automatic adjustment of atrioventricular delay (AVD) with SyncAV has been shown to improve electrical synchrony with either biventricular (BiV) or left ventricular (LV) only pacing. Selecting the optimal pacing mode may be guided by measuring conduction delays between the right atrium (RA), right ventricle (RV), and LV.

Purpose

Evaluate correlations between inter-chamber conduction delays and the QRS duration (QRSd) reduction achieved by BiV or LV-only pacing with SyncAV.

Methods

CRT implant patients (LBBB, QRSd ≥ 150 ms) were prospectively enrolled. Blinded QRSd was measured from 12-lead ECG during BiV and LV-only pacing, with SyncAV enabled and optimized to minimize QRSd. Conduction delays were measured by the device from unipolar electrograms during pacing and sensing (e.g. RAp-RVs). Correlations between each delay and which mode had the narrower QRSd was assessed by binomial regression.

Results

In total, 68 patients were evaluated (66.1 yr, 67.1% male, 32.5% ischemic, 26.3% EF, 165.1 ms intrinsic QRSd). BiV+SyncAV and LV+SyncAV reduced QRSd by 23.8% and 21.3% (P&lt;0.001) vs. intrinsic conduction. Of all delays, RVs-LVs and LVp-RVs were significantly correlated with patient probability of BiV+SyncAV yielding a narrower QRSd than LV+SyncAV. BiV+SyncAV was favored in 70.6% (48/68) of all patients, but was favored in 92.3% (24/26) of patients with LVp-RVs &lt; median (143 ms) (P=0.030 vs all).

Conclusion

When combined with SyncAV, BiV yielded a narrower QRSd than LV-only in the majority of patients, but was favored in a greater proportion who exhibit LVp-RVs delays below the median. Such conduction delay cut-offs can be used to facilitate pacing mode selection.

Genotype-Phenotype Correlation of SCN5A Genotype in Patients With Brugada Syndrome and Arrhythmic Events: Insights From the SABRUS in 392 Probands

BACKGROUND

Brugada syndrome (BrS) is associated with mutations in the cardiac sodium channel gene, SCN5A. However, genetic studies of patients with BrS with arrhythmic events have been limited. We sought to compare various clinical, ECG, and electrophysiological parameters according to SCN5A genotype in a large cohort of BrS probands with first arrhythmic event.

METHODS

Survey on Arrhythmic Events in Brugada Syndrome is a survey of 10 Western and 4 Asian countries, gathering 678 patients with BrS with first arrhythmic event. Only probands were included, and SCN5A genotype adjudicated. Patients without appropriate genetic data were excluded. Associations of genotype with clinical features were analyzed.

RESULTS

The study group comprised 392 probands: 92 (23.5%) SCN5A+(44 pathogenic/likely pathogenic [P/LP] and 48 variants of unknown significance) and 300 (76.5%) SCN5A-.SCN5A missense variants and the patients hosting them were similar regardless of adjudication. A higher proportion of patients with P/LP were pediatric (<16 years) compared with SCN5A- (11.4% versus 3%, P=0.023). The proportion of females was higher among patients with P/LP compared with SCN5A- (18.2% versus 6.3%, P=0.013). P/LP probands were more likely to have a family history of sudden cardiac death compared with SCN5A- (41.9% versus 16.8%, P<0.001). A higher proportion of patients with P/LP were White compared with SCN5A- (87.5% versus 47%, P<0.001). Ethnicity (odds ratio, 5.41 [2.8-11.19], P<0.001) and family history of sudden cardiac death (odds ratio, 2.73 [1.28-5.82], P=0.009) were independent variables associated with P/LP genotype following logistic regression.

CONCLUSIONS

The genetic basis of BrS has a complex relationship with gender, ethnicity, and age. Probands hosting a P/LP variant tended to experience their first arrhythmic event at a younger age and to have events triggered by fever compared with patients with SCN5A-. In addition, they were more likely to be White and to have family history of sudden cardiac death. Among females, a P/LP variant suggests an increased risk of being symptomatic. This association should be further studied on an ethnically specific basis in large prospectively collected international cohorts.

The prevalence of left and right bundle branch block morphology ventricular tachycardia amongst patients with arrhythmogenic cardiomyopathy and sustained ventricular tachycardia: insights from the European Survey on Arrhythmogenic Cardiomyopathy

AIMS

In arrhythmogenic cardiomyopathy (ACM), sustained ventricular tachycardia (VT) typically displays a left bundle branch block (LBBB) morphology while a right bundle branch block (RBBB) morphology is rare. The present study assesses the VT morphology in ACM patients with sustained VT and their clinical and genetic characteristics.

METHODS AND RESULTS

Twenty-six centres from 11 European countries provided information on 954 ACM patients who had ≥1 episode of sustained VT spontaneously documented during patients' clinical course. Arrhythmogenic cardiomyopathy was defined according to the 2010 Task Force Criteria, and VT morphology according to the QRS pattern in V1. Overall, 882 (92.5%) patients displayed LBBB-VT alone and 72 (7.5%) RBBB-VT [alone in 42 (4.4%) or in combination with LBBB-VT in 30 (3.1%)]. Male sex prevalence was 79.3%, 88.1%, and 56.7% in the LBBB-VT, RBBB-VT, and LBBB + RBBB-VT groups, respectively (P = 0.007). First RBBB-VT occurred 5 years after the first LBBB-VT (46.5 ± 14.4 vs 41.1 ± 15.8 years, P = 0.011). An implanted cardioverter-defibrillator was more frequently implanted in the RBBB-VT (92.9%) and the LBBB + RBBB-VT groups (90%) than in the LBBB-VT group (68.1%) (P < 0.001). Mutations in PKP2 predominated in the LBBB-VT (65.2%) and the LBBB + RBBB-VT (41.7%) groups while DSP mutations predominated in the RBBB-VT group (45.5%). By multivariable analysis, female sex was associated with LBBB + RBBB-VT (P = 0.011) while DSP mutations were associated with RBBB-VT (P < 0.001). After a median follow-up of 103 (51-185) months, death occurred in 106 (11.1%) patients with no intergroup difference (P = 0.176).

CONCLUSION

RBBB-VT accounts for a significant proportion of sustained VTs in ACM. Sex and type of pathogenic mutations were associated with VT type, female sex with LBBB + RBBB-VT, and DSP mutation with RBBB-VT.

Impact of pacing configuration and right ventricular lead location on dynamic atrioventricular delay optimization

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Abbott

Introduction

Automatic adjustment of atrioventricular delay (AVD) with SyncAV has been shown to improve electrical synchronization. However, the effect of pacing configuration and right ventricular (RV) lead location on SyncAV programming is unknown.

Purpose

  Evaluate the effect of pacing configuration and lead location on SyncAV optimization during biventricular (BiV) and LV-only pacing, with and without MultiPoint Pacing (MPP).

Methods

  Patients with LBBB and QRS duration (QRSd) ≥ 150 ms scheduled for CRT-P/D device implantation with quadripolar LV lead were enrolled in this prospective study. RV lead location was classified at implant by the operator via  fluoroscopy. QRSd was measured post-implant from 12-lead surface ECG by blinded experts during the following pacing modes: intrinsic conduction, BiV (BiV = RV + LV1), MPP (MPP = RV + LV1 + LV2), LV-only single-site (LVSS = LV1 only), and LV-only MPP (LVMPP = LV1 + LV2). For each mode, SyncAV was enabled (e.g. BiV + SyncAV) with the patient-tailored SyncAV offset that minimized QRSd. For BiV and LVSS, LV1 was the latest activating LV cathode; for MPP and LVMPP, LV1 + LV2 were the two LV cathodes with the widest possible separation (≥30mm). All modes used minimal RV-LV and LV1-LV2 delays.

Results

  Fifty-three patients (68% male, 36% ischemic, 26% ejection fraction, 169 ms intrinsic QRSd) completed device implant and QRSd assessment. RV leads were implanted in either the septum (48%) or apex (52%), according to implanting physician preference. Relative to intrinsic conduction, BiV + SyncAV and MPP + SyncAV reduced QRSd by 23% and 27%, respectively (p &lt; 0.01). LVSS + SyncAV reduced QRSd by 22% (p &lt; 0.01 vs BiV + SyncAV), and LVMPP + SyncAV reduced QRSd by 25% (p &lt; 0.05 vs MPP + SyncAV). RV apex or septum lead location did not have a significant impact on QRS reduction for each pacing configuration. As a percent of PR interval, optimal SyncAV offsets were similar for BiV + SyncAV and MPP + SyncAV (16% vs 13%, p = 0.05), and for LVSS + SyncAV and LVMPP + SyncAV (18% vs 21%, p = 0.46), but were significantly higher for LV-only settings vs. corresponding BiV/MPP settings (p &lt; 0.05 for both pairs). For BiV + SyncAV, apical vs septal RV leads required greater SyncAV offsets (22% vs 11%, p &lt; 0.05). SyncAV offsets also tended to be higher in apical vs septal RV leads for MPP (21% vs 11%), LVSS (20% vs 15%), and LVMPP (25% vs 16%), but without statistical significance.

Conclusion

SyncAV improves acute electrical synchronization in CRT patients with LBBB, particularly with patient-specific SyncAV programming. Pacing configuration (RV + LV or LV only, with or without MPP) and RV lead location (apex or septum) could potentially influence optimal SyncAV programming. Abstract Figure.

The uraemic hypertensive patient: a therapeutic challenge—right you are (if you think so)

High blood pressure (BP) is a leading cause of chronic kidney disease (CKD) and at the same time represents its most frequent complication. High BP is an independent risk factor for advanced CKD; on the other hand, at least 40% of patients with normal glomerular filtration rate (GFR) and virtually all patients with GFR <30 mL/min are hypertensive. CKD and microalbuminuria are powerful risk factors for cardiovascular morbidity and mortality. Consequently, in uraemic hypertension, it is of utmost importance to carefully manage both high BP and microalbuminuria, in order to slow down the progression of kidney damage and to reduce the incidence of cardiovascular events. The first purpose of the medical treatment in hypertensive patients is to normalize BP, regardless of the drug used. Nevertheless, some drugs have an ‘additional’ nephroprotective effect at the same BP target achieved. In this regard, first-line drugs are definitely renin–angiotensin–aldosterone inhibitors, mainly for their proved efficacy in reducing hypertension-related kidney damage and proteinuria. Anyway, a combined approach (two or more drugs) is usually needed to achieve the optimal BP target and reduce the worsening of CKD.

Assessment of OMT-28, a synthetic analog of omega-3 epoxyeicosanoids, in patients with persistent atrial fibrillation: Rationale and design of the PROMISE-AF phase II study

We designed a placebo controlled, double-blind, randomized, dose-finding phase II study on OMT-28 in the maintenance of sinus rhythm after electrical cardioversion (DCC) in patients with persistent atrial fibrillation (PROMISE-AF). OMT-28 is a first-in-class, synthetic analog of 17,18-epoxyeicosatetetraenoic acid, a bioactive lipid mediator generated by cytochrome P450 enzymes from the omega-3 fatty acid eicosapentaenoic acid. OMT-28 improves Ca²⁺-handling and mitochondrial function in cardiomyocytes and reduces pro-inflammatory signaling. This unique mode of action may provide a novel approach to target key mechanism contributing to AF pathophysiology. In a recent phase I study, OMT-28 was safe and well tolerated and showed favorable pharmacokinetics. The PROMISE-AF study (NCT03906799) is designed to assess the efficacy (primary objective), safety, and population pharmacokinetics (secondary objectives) of three different doses of OMT-28, administered once daily, versus placebo until the end of the follow-up period. Recruitment started in March 2019 and the study will include a total of 120 patients. The primary efficacy endpoint is the AF burden (% time with any AF), evaluated over a 13-week treatment period after DCC. AF burden is calculated based on continuous ECG monitoring using an insertable cardiac monitor (ICM). The primary efficacy analysis will be conducted on the modified intention-to-treat (mITT) population, whereas the safety analysis will be done on the safety population. Although ICMs have been used in other interventional studies to assess arrhythmia, PROMISE-AF will be the first study to assess antiarrhythmic efficacy and safety of a novel rhythm-stabilizing drug after DCC by using ICMs.

P1151Impact of ARNI (LCZ696) on patients selection for ICD implantation in SCD primary prevention: a real-world experience

Background

 ICD implantation is recommended for primary prevention in patients with symptomatic NYHA II-III heart failure with reduced ejection fraction (&lt; 35%) (HFrEF) and without left ventricle ejection fraction (LVEF) improvement despite at least three months of guideline-directed therapy. The use of angiotensin receptor-neprilysin inhibition with LCZ696 has shown to ameliorate left ventricle function and to reduce the ventricular arrhythmias burden in patients with HFrEF.

Purpose

The profile of patients with HFrEF who may benefit from therapy with LCZ696 without further requiring an ICD in primary prevention is still unknown. We aimed to assess the prevalence of these patients and to find potential clinical predictors of responsiveness to this treatment.

Methods

 We enrolled consecutive patients that started LCZ696 treatment for medical therapy optimization in the heart failure clinic of our institution. All of them were previously implanted with an ICD before LCZ696 availability (from 2009 to 2015). A cardiologist evaluated their home medications, clinical, and echocardiographic characteristics both at baseline (before starting LCZ696) and during follow up. The patients were grouped also according to the etiology of HF (ischemic/non-ischemic) and by gender. Patients were excluded if candidates to cardiac resynchronization therapy. Responsiveness to LCZ696 treatment was defined as an increase of LVEF to values &gt; 35% at follow up (FU).

Results

A total of 49 patients (67.1 ± 9.8 years of age) were enrolled in this study and followed in the heart failure clinic of our institution (mean follow up 11.5 ± 4.9 months). Among them, 19 patients (38%) showed an increase in LVEF to values &gt; 35% at follow up and a significant improvement in LVEF was appreciated (baseline LVEF: 31.2 ± 4.5 vs. follow up LVEF: 35.4 ± 8.0; p 0.003). No significant differences were recorded at baseline in LVEF within HF etiology and gender groups. At follow up, we found a significant increase in post-therapy LVEF only in the non-ischemic etiology group (from 31.5 ± 4.4 to 37.1 ± 8.1, p = 0.001) and in the male group (from 31.4 ± 4.5 to 34.9 ± 7.9, p = 0.005) in comparison with the ischemic etiology and the female group, respectively. No significant statistical differences were appreciated between responders and non-responders neither in terms of home medications nor in the LCZ696 doses, both at baseline and follow up.

Conclusion

This study suggests a potential impact of angiotensin receptor-neprilysin inhibition therapy in the selection of patients with HFrEF candidates to ICD in primary prevention. In this real-world experience from our HF clinic, we found a significant LVEF improvement in approximately 40% of patients treated with LCZ696. These patients, in FU evaluation, would not have needed for an ICD implantation. This benefit appears related to the non-ischemic etiology of HF and the male gender.

Abstract Figure. LVEF VARIATIONS

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.

841Multi-center clinical experience with the usage of implantable pulse generators for permanent his bundle pacing

Funding Acknowledgements

Abbott

Introduction

His Bundle pacing (HBP) offers a more physiologic pacing approach to maintain electrical synchrony. Permanent HBP has emerged as a feasible and safe alternative to traditional pacemaker therapy and cardiac resynchronization therapy (CRT) with clinical and electrophysiological advantages. However, traditional implantable pulse generators (IPGs) have been used for HBP without supporting algorithms developed for HBP.

Objective

To assess a multi-center clinical experience with the usage of IPGs for permanent HBP and to identify the needs for HBP specific device algorithms.

Methods

Patients from 6 centers worldwide with a permanent HBP lead and an existing Abbott pacemaker, defibrillator, or CRT device were enrolled in this study. Device data and 12-lead surface ECG were collected simultaneously during device interrogation at a follow-up visit. HBP capture types at different pacing amplitudes were adjudicated using 12-lead ECG. Bundle branch block (BBB) correction by HBP was defined as QRS duration ≤130 ms or narrowing by &gt;20%. Amplitudes of atrial and ventricular components on the HBP lead from both unipolar and bipolar sensing configurations were measured. Amplitudes of atrial component ≥ 0.5 mV on HB sensing EGMs were measured and considered as having risk of atrial oversensing.

Results

A total of 133 patients (75 ± 10 yrs, 92 male) were enrolled and completed study data collection post implant (median: 48, range: 0-3110 days). Patient characteristics, IPG type, and HBP lead connections were shown in the table. Dual-chamber pacemaker with HBP lead connected to V port was the most popular (65%) configuration. In non-BBB patients, pacing thresholds for selective HB (n = 44), non-selective HB (n = 54), and myocardial capture (n = 21) were 1.5 ± 1.2, 2.9 ± 2.0, 1.4 ± 1.5 V, respectively, at pulse width of 0.8 ± 0.4 ms. In BBB patients, LBBB and RBBB were corrected in 10/23 (43%) and 12/27 (44%) patients with pacing thresholds of 3.5 ± 2.4 and 2.1 ± 2.0 V, respectively, at pulse width of 0.8 ± 0.3 ms. AutoCapture™ algorithm was tested in 63 patients and recommended to be OFF in 28 (44%) patients. EGMs during intrinsic AV conduction were collected in 86 patients. A risk of atrial oversensing was identified in 24 (28%) and 27 (31%) patients during bipolar and unipolar sensing, respectively, and in 17 (20%) patients during both configurations. The average amplitude of the atrial and ventricular components on the HB lead EGM were 2.1 ± 2 and 6.0 ± 5.8 mV during bipolar sensing and 1.3 ± 1.2 and 6.3 ± 6.5 mV during unipolar sensing, respectively. Five (6%) patients had A/V amplitude ratios higher than 1.

Conclusions

Currently, various device configurations are used to overcome the fact that IPGs are not designed for HBP. Additionally, HBP presents unique challenges to ensure appropriate capture and sensing beyond traditional RV pacing. HBP specific device algorithms are needed to ensure correct IPG usage and facilitate device programming.

Abstract Figure.

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.

862Syncav with multipoint pacing improves acute left ventricular hemodynamics

Funding Acknowledgements

Abbott

Introduction

SyncAV has been shown to improve electrical synchronization by automatically adjusting atrioventricular delay (AVD) according to the intrinsic atrioventricular conduction time. Additional incremental electrical synchronization may be gained by the addition of second left ventricular (LV) pulse with MultiPoint Pacing (MPP). While the electrical synchronization benefits of SyncAV have been previously explored, there has been no assessment of the acute hemodynamic impact of SyncAV with or without MPP.

Objective

 Evaluate the acute LV hemodynamic impact of SyncAV with and without MPP.

Methods

Heart failure patients with LBBB and QRS duration (QRSd) &gt; 140 ms undergoing CRT-P/D implant with a quadripolar LV lead were enrolled in this prospective study. A guidewire or catheter with pressure transducer was placed in the LV chamber and the maximum pressure change (dP/dtmax) was recorded during the following pacing modes:  intrinsic conduction, conventional biventricular pacing with SyncAV (BiV + SyncAV), and MPP with SyncAV (MPP + SyncAV). Twelve-lead surface ECG was used to determine the patient-tailored SyncAV offset that minimized QRSd.

Results

Twenty-seven patients (67% male, 44% ischemic, 30 ± 7% ejection fraction) completed the acute recordings. Relative to the intrinsic QRSd of 163 ms, BiV + SyncAV reduced QRSd by 21.5% to 124 ms (p &lt; 0.001 vs. intrinsic) and MPP + SyncAV reduced QRSd by 26.6% to 120 ms (p &lt; 0.05 vs. BiV + SyncAV). Beyond electrical synchronization, SyncAV significantly improved acute hemodynamics. Relative to the intrinsic dP/dtmax of 842 mmHg/s, BiV + SyncAV elevated dP/dtmax by 6.3% to 900 mmHg/s (p &lt; 0.001 vs. intrinsic) and MPP + SyncAV elevated dP/dtmax by 8.8% to 926 mmHg/s (p &lt; 0.005 vs. BiV + SyncAV). Despite both QRSd and dP/dtmax improvement with SyncAV and MPP, correlation between electrical and hemodynamic measurements was poor (R2 = 0.0 for BiV + SyncAV, R2 = 0.1 for MPP + SyncAV).

Conclusion

SyncAV may significantly improve acute LV hemodynamics in addition to electrical synchrony in LBBB patients. Further incremental improvement was achieved by combining SyncAV with MPP.

Abstract Figure.

43Dynamic atrioventricular delay achieves superior electrical synchrony when pacing both ventricles rather than left ventricle alone

Funding Acknowledgements

Abbott

Introduction

Automatic adjustment of atrioventricular delay (AVD) with SyncAV has been shown to improve electrical synchronization when pacing one or two sites in the left ventricle together with the right ventricle. However, it is unknown if the same benefit can be gained by using SyncAV while pacing only the left ventricle without right ventricular pacing.

Purpose

  Evaluate the acute improvement in electrical synchrony provided by SyncAV with and without MultiPoint Pacing (MPP) during biventricular (BiV) and LV only pacing.

Methods

  Patients with LBBB and QRS duration (QRSd) ≥ 150 ms scheduled for CRT-P/D device implantation with quadripolar LV lead were enrolled in this prospective study. QRSd was measured post-implant from 12-lead surface electrograms by blinded experts during the following pacing configurations: intrinsic conduction, conventional BiV (BiV = RV + LV1), MPP (MPP = RV + LV1 + LV2), LV-only single-site (LVSS = LV1 only), and LV-only MPP (LVMPP = LV1 + LV2). For each pacing mode, SyncAV was enabled (e.g. BiV + SyncAV) with the patient-tailored SyncAV offset that minimized QRSd. As an additional reference, QRSd during BiV was also measured using the nominal static AVD (paced/sensed AVD = 140/110 ms). BiV and LVSS pacing used the latest activating LV cathode, whereas MPP and LVMPP used the two LV cathodes with the widest possible separation (&gt;30mm). All configurations used the minimum programmable RV-LV and LV1-LV2 delays.

Results

  Thirty-five patients (78% male, 33% ischemic, 26% ejection fraction, 165 ms intrinsic QRSd) completed device implant and QRSd assessment. Relative to intrinsic conduction, BiV with nominal AVD reduced the QRSd by 17.5% (p &lt; 0.001 vs intrinsic). Enabling SyncAV with a patient-optimized offset significantly improved QRSd reduction. BiV + SyncAV reduced QRSd by 25.2% (p &lt; 0.001 vs. BiV). The greatest QRSd reduction of 28.9% was achieved by MPP + SyncAV (p &lt; 0.01 vs. BiV + SyncAV). Single- and multi-site LV-only pacing reduced QRSd significantly less than corresponding biventricular modes. LVSS + SyncAV reduced QRSd by 22.5% (p &lt; 0.05 vs. BiV + SyncAV), and LVMPP + SyncAV reduced QRSd by 24.3% (p &lt; 0.05 vs. MPP + SyncAV). As a percent of PR interval, optimal SyncAV offsets were similar for BiV + SyncAV (median: 13%, mean: 17%) vs. MPP + SyncAV (median: 13%, mean 16%, p = 0.35 vs. BiV + SyncAV), and similar for LVSS + SyncAV (median: 20%, mean: 28%) and LVMPP + SyncAV (median: 23%, mean: 26%, p = 0.35 vs. LVSS + SyncAV), but were significantly higher for LV-only settings vs. corresponding BiV/MPP settings (p &lt; 0.01 for both pairs). Conclusion: Greater improvement in electrical synchrony using SyncAV was observed when right ventricular pacing was included with left ventricular pacing. Additional benefit was gained by the addition of a second left ventricular pacing site with MPP in combination with SyncAV in both biventricular and LV only pacing modes.

Abstract Figure.

Characterization and Management of Arrhythmic Events in Young Patients With Brugada Syndrome

BACKGROUND

Information on young patients with Brugada syndrome (BrS) and arrhythmic events (AEs) is limited.

OBJECTIVES

The purpose of this study was to describe their characteristics and management as well as risk factors for AE recurrence.

METHODS

A total of 57 patients (age ≤20 years), all with BrS and AEs, were divided into pediatric (age ≤12 years; n = 26) and adolescents (age 13 to 20 years; n = 31).

RESULTS

Patients' median age at time of first AE was 14 years, with a majority of males (74%), Caucasians (70%), and probands (79%) who presented as aborted cardiac arrest (84%). A significant proportion of patients (28%) exhibited fever-related AE. Family history of sudden cardiac death (SCD), prior syncope, spontaneous type 1 Brugada electrocardiogram (ECG), inducible ventricular fibrillation at electrophysiological study, and SCN5A mutations were present in 26%, 49%, 65%, 28%, and 58% of patients, respectively. The pediatric group differed from the adolescents, with a greater proportion of females, Caucasians, fever-related AEs, and spontaneous type-1 ECG. During follow-up, 68% of pediatric and 64% of adolescents had recurrent AE, with median time of 9.9 and 27.0 months, respectively. Approximately one-third of recurrent AEs occurred on quinidine therapy, and among the pediatric group, 60% of recurrent AEs were fever-related. Risk factors for recurrent AE included sinus node dysfunction, atrial arrhythmias, intraventricular conduction delay, or large S-wave on ECG lead I in the pediatric group and the presence of SCN5A mutation among adolescents.

CONCLUSIONS

Young BrS patients with AE represent a very arrhythmogenic group. Current management after first arrhythmia episode is associated with high recurrence rate. Alternative therapies, besides defibrillator implantation, should be considered.

Clinical outcome of patients with the Brugada type 1 electrocardiogram without prophylactic implantable cardioverter defibrillator in primary prevention: a cumulative analysis of seven large prospective studies

Aims

Patients with the Brugada type 1 ECG (Br type 1) without previous aborted sudden death (aSD) who do not have a prophylactic ICD constitute a very large population whose outcome is little known. The objective of this study was to evaluate the risk of SD or aborted SD (aSD) in these patients.

Methods and results

We conducted a meta-analysis and cumulative analysis of seven large prospective studies involving 1568 patients who had not received a prophylactic ICD in primary prevention. Patients proved to be heterogeneous. Many were theoretically at low risk, in that they had a drug-induced Br type 1 (48%) and/or were asymptomatic (87%), Others, in contrast, had one or more risk factors. During a mean/median follow-up ranging from 30 to 48 months, 23 patients suffered SD and 1 had aSD. The annual incidence of SD/aSD was 0.5% in the total population, 0.9% in patients with spontaneous Br type 1 and 0.08% in those with drug-induced Br type 1 (P = 0.0001). The paper by Brugada et al. reported an incidence of SD more than six times higher than the other studies, probably as a result of selection bias. On excluding this paper, the annual incidence of SD/aSD in the remaining 1198 patients fell to 0.22% in the total population and to 0.38 and 0.06% in spontaneous and drug-induced Br type 1, respectively. Of the 24 patients with SD/aSD, 96% were males, the mean age was 39 ± 15 years, 92% had spontaneous Br type 1, 61% had familial SD (f-SD), and only 18.2% had a previous syncope; 43% had a positive electrophysiological study. Multiple meta-analysis of individual trials showed that spontaneous Br type 1, f-SD, and previous syncope increased the risk of SD/aSD (RR 2.83, 2.49, and 3.03, respectively). However, each of these three risk factors had a very low positive predictive value (PPV) (1.9-3.3%), while negative predictive values (NPV) were high (98.5-99.7%). The incidence of SD/aSD was only slightly higher in patients with syncope than in asymptomatic patients (2% vs. 1.5%, P = 0.6124). Patients with SD/aSD when compared with the others had a mean of 1.74 vs. 0.95 risk factors (P = 0.026).

Conclusion

(i) In patients with Br type 1 ECG without an ICD in primary prevention, the risk of SD/aSD is low, particularly in those with drug-induced Br type 1; (ii) spontaneous Br type 1, f-SD, and syncope increase the risk. However, each of these risk factors individually has limited clinical usefulness, owing to their very low PPV; (iii) patients at highest risk are those with more than one risk factor.

Biofilm in voice prosthesis: A prospective cohort study and laboratory tests using sonication and SEM analysis

OBJECTIVE

The objective of the study was to compare the biofilm growing pattern and its morphological extent on silicone and a teflon-like material using a sonication process and a Scanning Electron Microscope (SEM).

DESIGN

A prospective cohort study and a laboratory study.

SETTING

Otolaryngology -Head and Neck surgery Department and the Microbiology Institute.

PARTICIPANTS

The participants included fifteen laryngectomised patients with phonatory prostheses, which were removed because of device failure, and two different kinds of phonatory prostheses from the laboratory (Provox 2 and ActiValve) that were artificially colonised by Candida albicans.

MAIN OUTCOME MEASURES

Tracheo-oesophageal puncture (TEP) is currently considered the gold standard for post-laryngectomy voice rehabilitation. "Leakage" represents the most common cause of substitution and is generated by biofilm colonisation of the prosthesis by mixed mycotic and bacterial agents. New biomaterials have been developed that are deemed to be more resistant to the colonisation of micro-organisms and material deformation.

RESULTS

The devices showed colonisation by mixed bacterial flora (Staphylococci 13%, Streptococci 9%, and Haemophilus influenzae 5%) and by yeasts (Candida albicans 12%). Moreover, we observed a different distribution of biofilm layers in Provox ActiValve (22.56%) compared to Provox 2 (56.82%) after experimental colonisation by the previously isolated Candida strain.

CONCLUSION

Resident microbiological species from the upper airways unavoidably colonise the polymer surfaces, and no strategies have been effective except for the manipulation of the chemical-physical properties of the device's polymer. Our study confirms that Provox ActiValve, which is made with a fluoroplastic material (teflon-like), is less subject to in vitro colonisation by Candida, and thus showed a higher clinical resistance to biofilm and a longer lifespan. The sonication seems to significantly improve the knowledge of bacterial and mycotic flora in biofilm colonisation. The design of a device for the daily cleaning capable to reach and brush the oesophageal flange of the prosthesis preserving the valve mechanism could represent a practical and simple help in this still unsolved problem.

Age of First Arrhythmic Event in Brugada Syndrome

Background

Data on the age at first arrhythmic event (AE) in Brugada syndrome are from limited patient cohorts. The aim of this study is 2-fold: (1) to define the age at first AE in a large cohort of patients with Brugada syndrome, and (2) to assess the influence of the mode of AE documentation, sex, and ethnicity on the age at first AE.

Methods and Results

A survey of 23 centers from 10 Western and 4 Asian countries gathered data from 678 patients with Brugada syndrome (91.3% men) with first AE documented at time of aborted cardiac arrest (group A, n=426) or after prophylactic implantable cardioverter–defibrillator implantation (group B, n=252). The vast majority (94.2%) of the patients were 16 to 70 years old at the time of AE, whereas pediatric (<16 years) and elderly patients (>70 years) comprised 4.3% and 1.5%, respectively. Peak AE rate occurred between 38 and 48 years (mean, 41.9±14.8; range, 0.27–84 years). Group A patients were younger than in Group B by a mean of 6.7 years (46.1±13.2 versus 39.4±15.0 years; P <0.001). In adult patients (≥16 years), women experienced AE 6.5 years later than men ( P =0.003). Whites and Asians exhibited their AE at the same median age (43 years).

Conclusions

SABRUS (Survey on Arrhythmic Events in Brugada Syndrome) presents the first analysis on the age distribution of AE in Brugada syndrome, suggesting 2 age cutoffs (16 and 70 years) that might be important for decision-making. It also allows gaining insights on the influence of mode of arrhythmia documentation, patient sex, and ethnic origin on the age at AE.

A telemonitoring platform for the investigation of blood pressure profiles in pacemaker patients

Rate responsive pacemakers (PM) use different strategies to adapt the patient paced rate, with the aim of having the best hemodynamic performance in response to internal or external conditions. Closed-loop stimulation (CLS) uses intracardiac impedance as a sensor principle. The evaluation of impact of different pacing modalities and technologies on the blood pressure (BP) profiles is mainly investigated in short-term laboratory settings, mainly due to the need of reliable daily-based BP values. The impact of CLS pacing on systemic blood pressure (BP) has been studied on short term basis, but data on long term effects are scarse. This study present a telemedicine platform designed for evaluating the effect of the rate responsive technology on daily systolic and diastolic BP data. BP and pacemaker data were collected daily from fourteen patients during a 3 month period. The total number of monitoring days was 1277 (91 day/patient), for a total number of 4455 BP measures. On average 3.5 measure/day/patient were received). The analysis of the BP data showed that CLS pacing results in diastolic pressure closer to the normal values than accelerometer-based pacing, which were associated to lower diastolic pressures.

Treatment of inappropriate sinus tachycardia with ivabradine

BACKGROUND

Inappropriate sinus tachycardia (IST) often causes palpitations, dyspnea, and exercise intolerance, that are generally treated with beta blockers and non-dihydropyridine calcium-channel antagonists. Ivabradine, a selective inhibitor of cardiac pacemaker If current, has recently emerged as an effective and safe alternative to conventional drugs for IST.

METHODS

We performed a systematic overview of clinical studies on the therapeutic yield of ivabradine in patients with inappropriate sinus tachycardia, published in MEDLINE database from January 2000 to March 2015.

RESULTS

Overall, five case reports were found, all showing efficacy of ivabradine in subjects affected by IST. Eight non-randomized clinical studies demonstrated short- and medium-term safety and efficacy of ivabradine administration in IST, also in adjunction to or in comparison with metoprolol. One double-blind randomized crossover study also showed that ivabradine is superior to placebo for heart rate (HR) reduction and symptoms control in patients affected by IST.

CONCLUSIONS

Ivabradine is effective and safe in short- and medium-term treatment of IST. However, long-term follow-up studies and randomized studies comparing ivabradine with beta blockers are still lacking.

Prospective Use of Microvolt T-Wave Alternans Testing to Guide Primary Prevention Implantable Cardioverter Defibrillator Therapy

BACKGROUND

We hypothesized that a negative microvolt T-wave alternans (MTWA) test would identify patients unlikely to benefit from primary prevention implantable cardioverter defibrillator (ICD) therapy in a prospective cohort.

METHODS AND RESULTS

Data were pooled from 8 centers where MTWA testing was performed specifically for the purpose of guiding primary prevention ICD implantation. Cohorts were included if the ratio of ICDs implanted in patients who were MTWA "non-negative" to patients who were MTWA negative was >2:1, indicating that MTWA testing had a significant impact on the decision to implant an ICD. The pooled cohort included 651 patients: 371 MTWA non-negative and 280 MTWA negative. Among non-negative patients, 62% underwent ICD implantation whereas only 13% of MTWA-negative patients received an ICD (P<0.01). Despite a substantially lower prevalence of ICDs, long-term survival (6.9 years) was significantly better among MTWA-negative patients (68.2% non-negative vs. 87.1% negative, P=0.026).

CONCLUSIONS

MTWA-negative patients had significantly better survival than MTWA non-negative patients, the majority of whom had ICDs. Despite a very low prevalence of ICDs, long-term survival among patients with left ventricular ejection fraction ≤40% and a negative MTWA test was better than in the ICD arm of any study to date that has demonstrated a benefit of ICDs. This provides further evidence that MTWA-negative patients are unlikely to benefit from primary prevention ICD therapy.

Usefulness Of Ivabradine To Treat "unexpected" Heart Failure Caused By "acute" Right Ventricular Pacing

We present the case of a patient with a heart failure episode induced by acute right ventricular pacing. After reversal of beta-blockers because of chronic obstructive pulmonary disease (COPD) exacerbation, the following sinus tachycardia caused a 2:1 atrioventricular block and consequent continuous right ventricular pacing. He was treated with the selective I(f) inhibitor ivabradine, that reduced both ventricular pacing percentage and heart rate without affecting atrioventricular conduction. Ivabradine may be a valuable option in treatment of patients with atrioventricular conduction disturbances.

Risk stratification in individuals with the Brugada type 1 ECG pattern without previous cardiac arrest: usefulness of a combined clinical and electrophysiologic approach

AIMS

Risk stratification in individuals with type 1 Brugada electrocardiogram (ECG) pattern (type 1 ECG) for primary prevention of sudden death (SD).

METHODS AND RESULTS

Three hundred and twenty patients (258 males, median age 43 years) with type 1 ECG were enrolled. No patient had previous cardiac arrest. Fifty-four per cent of patients had a spontaneous and 46% a drug-induced type 1 ECG. One-third had syncope, two-thirds were asymptomatic. Two hundred and forty-five patients underwent electrophysiologic study (EPS) and 110 patients received an implantable cardiac defibrillator (ICD). During follow-up [median length 40 months (IQ20-67)], 17 patients had major arrhythmic events (MAE) (14 resuscitated ventricular fibrillation (VF) and three SD). Both a spontaneous type 1 ECG and syncope significantly increased the risk (2.6 and 3.0% event rate per year vs. 0.4 and 0.8%). Major arrhythmic events occurred in 14% of subjects with positive EPS, in no subjects with negative EPS and in 5.3% of subjects without EPS. All MAE occurred in subjects who had at least two potential risk factors (syncope, family history of SD, and positive EPS). Among these patients, those with spontaneous type 1 ECG had a 30% event rate.

CONCLUSION

(1) In subjects with the Brugada type 1 ECG, no single clinical risk factor, nor EPS alone, is able to identify subjects at highest risk; (2) a multiparametric approach (including syncope, family history of SD, and positive EPS) helps to identify populations at highest risk; (3) subjects at highest risk are those with a spontaneous type 1 ECG and at least two risk factors; (4) the remainder are at low risk.

A randomized double-blind comparison of biventricular versus left ventricular stimulation for cardiac resynchronization therapy: the Biventricular versus Left Univentricular Pacing with ICD Back-up in Heart Failure Patients (B-LEFT HF) trial

BACKGROUND

Biventricular (BiV) stimulation is the preferred means of delivering cardiac resynchronization therapy (CRT), although left ventricular (LV)-only stimulation might be as safe and effective. B-LEFT HF is a prospective, multicenter, randomized, double-blind study aimed to examine whether LV-only is noninferior to BiV pacing regarding clinical and echocardiographic responses.

METHODS

B-LEFT HF randomly assigned 176 CRT-D recipients, in New York Heart Association class III or IV, with an LV ejection fraction < or =35% and QRS > or =130 milliseconds, to a BiV (n = 90) versus LV (n = 86) stimulation group. Clinical status and echocardiograms were analyzed at baseline and 6 months after CRT-D implant to test the noninferiority of LV-only compared with BiV stimulation.

RESULTS

The proportion of responders was in line with current literature on CRT, with improvement in heart failure composite score in 76.2% and 74.7% of patients in BiV and LV groups, respectively. Comparing LV versus BiV pacing, the small differences in response rates and corresponding 95% CI indicated that LV pacing was noninferior to BiV pacing for a series of response criteria (combination of improvement in New York Heart Association and reverse remodeling, improvement in heart failure composite score, reduction in LV end-systolic volume of at least 10%), both at intention-to-treat and at per-protocol analysis.

CONCLUSIONS

Left ventricular-only pacing is noninferior to BiV pacing in a 6-month follow-up with regard to clinical and echocardiographic responses. Left ventricular pacing may be considered as a clinical alternative option to BiV pacing.

Relation of C-reactive protein to long-term risk of recurrence of atrial fibrillation after electrical cardioversion

The aim of this study is to assess the role of C-reactive protein (CRP) in predicting long-term risk of atrial fibrillation (AF) recurrence after electrical cardioversion. CRP levels are associated with the presence of AF and failure of electrical or pharmacologic cardioversion, but no previous study has assessed their predictive role in long-term follow-up after successful electrical cardioversion. One hundred two consecutive patients (age 67 +/- 11 years; 58 men) with nonvalvular persistent AF who underwent successful biphasic electrical cardioversion were studied. High-sensitivity CRP was measured immediately before cardioversion. Follow-up was performed up to 1 year in all cases. Patients were divided into 4 groups according to CRP quartiles. Patients in the lowest CRP quartile (<1.9 mg/L) had significantly lower rates of AF recurrence (4% vs 33% at 3 months in the other 3 groups combined, p = 0.007, and 28% vs 60% at 1 year, p = 0.01). The 4 groups were similar in age, gender, ejection fraction, and left atrial size. Survival analysis confirmed that patients in the lowest CRP quartile had a lower recurrence rate (p = 0.02). Cox regression analyses using age, gender, hypertension, diabetes, ejection fraction, left atrial diameter, use of antiarrhythmic drugs, angiotensin-converting enzyme inhibitors or angiotensin II antagonists, and statins, and CRP quartiles as covariates showed that only CRP was independently associated with AF recurrence during follow-up (hazard ratio 4.98, 95% confidence interval 1.75 to 14.26, p = 0.003). In conclusion, low CRP is associated with long-term maintenance of sinus rhythm after cardioversion for nonvalvular AF.