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Highly trained athletes show an increased risk of atrial arrhythmias. Little is known about atrial volumes and function during exercise in this population. Our aim was to analyze atrial size and contractile function during exercise. Fifty endurance athletes with 11 ± 8 h of training per week and 30 sedentary control subjects were included. Echocardiography was performed at baseline and during exercise. Left ( LA) and right atrial ( RA) size and function were assessed by two-dimensional echocardiography. Peak negative strain (Sa) during atrial contraction and active atrial emptying volume ( AEV) were measured. Athletes and control subjects showed a significant increment of deformation and AEV of both atria with exercise ( P < 0.01 vs baseline for LA and RA). Among athletes, a subgroup with significant LA ( n = 8)/ RA ( n = 15) dilatation (≥40 mL/m2) showed a significantly lower increment in AEV with exercise ( LA∆ AEV: 1.4 ± 1.1 mL/m2 vs 2.1 ± 0.9 mL/m2, P = 0.04; RA∆ AEV: 0.9 ± 0.8 mL/m2 vs 2.3 ± 1.1 mL/m2, P < 0.01) and lower increment in deformation vs other athletes ( LA∆Sa: −3.2 ± 2.9% vs −9.5 ± 4.4%, P < 0.01; RA∆Sa: −2.5 ± 3.3% vs. −9.8 ± 3.3%, P < 0.01). During exercise, active atrial strain increases, but less in athletes compared to controls, but due to larger atrial volumes, they reached similar increases in atrial emptying volume. However, this overall lesser deformation increases from a subgroup with significant atrial dilatation showing impairment in atrial contractile reserve. [ABSTRACT FROM AUTHOR]

Premature ventricular complex are common findings in the exam of many athletes. There is no extensive scientific evidence in the management of this situation particularly when associated with borderline contractile function of the left ventricle. In this case report, we present a 35-year-old asymptomatic healthy athlete with high incidence (over 10 000 beats in 24 h) of premature ventricular complex and left ventricular dilatation with dysfunction, which persisted after a resting period of 6 months without training. We performed radiofrequency ablation of the premature ventricular complex focus. After 1-year follow-up, he was asymptomatic without arrhythmia and the left ventricle normalized its size and function as shown by echocardiogram and cardiac magnetic resonance. [ABSTRACT FROM AUTHOR]

Aim: Current guidelines recommend atrioventricular junction (AVJ) ablation in patients with atrial fibrillation (AF) treated with cardiac resynchronization therapy (CRT). Our study compared the CRT response of patients in sinus rhythm (SR) vs. AF. Methods and Results: In this observational, prospective, multicentre study, patients were grouped by intrinsic rhythm. For the first 2 months, the negative chronotropic drug was optimized in the AF group. If ventricular pacing was ≤85%, AVJ ablation was recommended. Responders were defined as patients who survived without requiring heart transplant and had a ≥ 10% reduction in left ventricular end-systolic volume (LVESV) at 12 months after implantation. Of 202 patients included, 156 (77%) were in SR and 46 (23%) had AF. After drug optimization, only 13/46 (28%) of the AF patients required AVJ ablation (AF + AVJ). The percentage of responders was 83/156 (53%) for SR vs. 22/46 (48%) AF (P = 0.4). Among AF patients the response was 16/33 (48%) for AF with non-AVJ ablation vs. 6/13 (46%) AF + AVJ, P = 0.56. The LVESV decreased in all three groups: -30 ± 39 mL, -24 ± 43 mL, and -22 ± 36 mL, respectively (P = 0.75). Mortality was higher in patients with AF compared with SR: 10/46 (21%) vs. 9/156 (5.7%), log rank 10.6, P <0.05. Conclusion: Although only 28% of the patients in AF had the AVJ ablated, there were no differences in the percentage of response and echo improvement between patients in SR and AF. However, mortality was higher in patients with AF compared with patients in SR. [ABSTRACT FROM AUTHOR]

Introduction: Measurement of left ventricular (LV) asynchrony is usually determined on single time points from spectral tissue Doppler imaging (TDI) scans that are frequently difficult to identify or not representative of the whole cardiac cycle. Our aim was to validate a new asynchrony index that evaluates the motion of the LV walls throughout the whole cardiac cycle. Methods and Results: Ten healthy volunteers and 50 patients undergoing cardiac resynchronization therapy (CRT) were studied with TDI. Wall displacement tracings from the septal and lateral LV walls were analyzed. Cross-correlation was calculated and 2 indices were obtained to assess LV asynchrony: the time delay and the superposition index (SI) between wall displacements. These results were compared between healthy volunteers and CRT patients, and between responders and nonresponders to CRT. Also, the optimal interventricular (VV) interval was based upon the best matching level. Volunteers showed lower asynchrony indices (83 ± 2% SI, 17 ± 8 ms time delay) as compared with CRT patients (63 ± 15% SI, 73 ± 60 ms time delay, P < 0.05). Responders also had more LV dyssynchrony than nonresponders (58 ± 15% SI and 92 ± 66 ms vs 68 ± 12% and 48 ± 34 ms, P < 0.05). The optimum VV interval selected by the computed algorithm showed an excellent concordance (Kappa = 0.90, P < 0.05) with that determined by other validated methods for optimizing the programming of CRT devices. Conclusions: This approach allows measurement of LV intraventricular asynchrony throughout the cardiac cycle, being useful to determine the optimum VV interval and to select candidates for CRT. [ABSTRACT FROM AUTHOR]

Conventional tilt test protocols are time consuming and there is no consensus regarding the optimal duration of the test and the provocative drug to be used. This study evaluated the diagnostic power of a short nitroglycerine test against a conventional isoproterenol protocol. A cohort of 128 patients with unexplained syncope was studied. A group of 64 consecutive patients were tilted with a short nitroglycerine test consisting of a passive phase of 15 minutes and if this proved negative, 400 microg of sublingual nitroglycerin spray for a further 15 minutes. The control group consisted of 64 patients tilted with a conventional isoproterenol protocol with a passive phase of 30 minutes and a drug-challenge phase of 20 minutes. In the nitroglycerine protocol 39 (60.9%) patients showed a positive response versus 27(42.2%) in the isoproterenol group (P = 0.034). The duration of the protocol was 23.2 +/- 7.2 minutes in the nitroglycerine group versus 41.1 +/- 15.5 minutes with isoproterenol (P = 0.001). The time until syncope was 18.87 +/- 6.1 versus 29 +/- 18, respectively (P = 0.002). For evaluating unexplained syncope the short tilt test protocol with nitroglycerine is less time consuming, easier to perform, and has a higher rate of positive response than a conventional isoproterenol protocol. [ABSTRACT FROM AUTHOR]

Two consecutive cases are presented of patients with ICDs in whom the use of commercial units for muscle stimulation for abdominal training caused interference with the device, mimicked cardiac signals, and resulted in inappropriate treatment shock delivery. [ABSTRACT FROM AUTHOR]

Background Left atrial structural remodeling contributes to the arrhythmogenic substrate of atrial fibrillation (AF), but the role of the right atrium (RA) remains unknown. Our aims were to comprehensively characterize right atrial structural remodeling in AF and identify right atrial parameters predicting recurrences after ablation. Methods and Results A 3.0 T late gadolinium enhanced-cardiac magnetic resonance was obtained in 109 individuals (9 healthy volunteers, 100 patients with AF undergoing ablation). Right and left atrial volume, surface, and sphericity were quantified. Right atrial global and regional fibrosis burden was assessed with validated thresholds. Patients with AF were systematically followed after ablation for recurrences. Progressive right atrial dilation and an increase in sphericity were observed from healthy volunteers to patients with paroxysmal and persistent AF; fibrosis was similar among the groups. The correlation between parameters recapitulating right atrial remodeling was mild. Subsequently, remodeling in both atria was compared. The RA was larger than the left atrium (LA) in all groups. Fibrosis burden was higher in the LA than in the RA of patients with AF, whereas sphericity was higher in the LA of patients with persistent AF only. Fibrosis, volume, and surface of the RA and LA, but not sphericity, were strongly correlated. Tricuspid regurgitation predicted right atrial volume and shape, whereas diabetes was associated with right atrial fibrosis burden; sex and persistent AF also predicted right atrial volume. Fibrosis in the RA was mostly located in the inferior vena cava-RA junction. Only right atrial sphericity is significantly associated with AF recurrences after ablation (hazard ratio, 1.12 [95% CI, 1.01-1.25]). Conclusions AF progression associates with right atrial remodeling in parallel with the LA. Right atrial sphericity yields prognostic significance after ablation.

Background: Longer QRS duration (QRSd) improves, but increased left ventricular (LV) end-diastolic volume (LVEDV) reduces, efficacy of cardiac resynchronization therapy (CRT). QRSd/LVEDV ratios differ between sexes. We hypothesized that in the EchoCRT (Echocardiography Guided Cardiac Resynchronization Therapy) trial enrolling patients with heart failure with QRSd <130 ms, those with larger LVEDV would deteriorate but those with the highest QRSd/LVEDV would improve with CRT., Methods and Results: Primary outcome in patients (n=787, 72% men, 93% New York Heart Association class III, QRSd <130 ms, LV ejection fraction ≤35%, LV dilation and dyssynchrony) randomized to CRT-ON or CRT-OFF and followed up for 19 months was compared according to LVEDV (height indexed) or QRSd/LVEDV ratio, in multivariable analysis. Structural remodeling was assessed echocardiographically 6 months after implantation. Patients with baseline LVEDV higher than or equal to median worsened with CRT (death/heart failure hospitalization: CRT-ON versus CRT-OFF, 35.2% versus 24.5% [hazard ratio, 1.64; 95% confidence interval, 1.11-2.42; P =0.012]), but those with LVEDV lower than median remained unaffected. Patients with the highest QRSd/LVEDV ratio improved with CRT (death/heart failure hospitalization in top quartile: 20.9% in CRT-ON [n=91] versus 28.3% in CRT-OFF [n=106] [hazard ratio, 0.64; 95% confidence interval, 0.34-1.24; P =0.188], versus the remaining quartiles: 31.7% in CRT-ON [n=300] versus 24.8% in CRT-OFF [n=290] [hazard ratio, 1.47; 95% confidence interval, 1.07-2.02; P =0.016], test for interaction P =0.046). QRSd and dyssynchrony were similar between groups. The 3-way test for interaction indicated no sex-specific effects. However, numerically, men with LVEDV higher than or equal to median accounted for worse outcomes of CRT-ON. Women, with the highest QRSd/LVEDV ratio exhibited significant reverse remodeling., Conclusion: CRT has opposite effects among patients with heart failure with QRSd <130 ms according to LV size: worsening outcomes in patients with larger LV, but inducing beneficial effects in those with smaller LV., Clinical Trial Registration: URL: https://www.clinicaltrials.gov/. Unique identifier: NCT00683696., (© 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: This study sought to assess payer costs following cryoballoon or radiofrequency current (RFC) catheter ablation of paroxysmal atrial fibrillation in the randomized FIRE AND ICE trial., Methods and Results: A trial period analysis of healthcare costs evaluated the impact of ablation modality (cryoballoon versus RFC) on differences in resource use and associated payer costs. Analyses were based on repeat interventions, rehospitalizations, and cardioversions during the trial, with unit costs based on 3 national healthcare systems (Germany [€], the United Kingdom [£], and the United States [$]). Total payer costs were calculated by applying standard unit costs to hospital stays, using International Classification of Diseases, 10th Revision diagnoses and procedure codes that were mapped to country-specific diagnosis-related groups. Patients (N=750) randomized 1:1 to cryoballoon (n=374) or RFC (n=376) ablation were followed for a mean of 1.5 years. Resource use was lower in the cryoballoon than the RFC group (205 hospitalizations and/or interventions in 122 patients versus 268 events in 154 patients). The cost differences per patient in mean total payer costs during follow-up were €640, £364, and $925 in favor of cryoballoon ablation ( P =0.012, 0.013, and 0.016, respectively). This resulted in trial period total cost savings of €245 000, £140 000, and $355 000., Conclusions: When compared with RFC ablation, cryoballoon ablation was associated with a reduction in resource use and payer costs. In all 3 national healthcare systems analyzed, this reduction resulted in substantial trial period cost savings, primarily attributable to fewer repeat ablations and a reduction in cardiovascular rehospitalizations with cryoballoon ablation., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Identifier: NCT01490814., (© 2017 The Authors and Medtronic. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: Biventricular pacing (CRT) shows clear benefits in heart failure with wide QRS, but results in narrow QRS have appeared conflicting. We tested the hypothesis that study design might have influenced findings., Method and Results: We identified all reports of CRT-P/D therapy in subjects with narrow QRS reporting effects on continuous physiological variables. Twelve studies (2074 patients) met these criteria. Studies were stratified by presence of bias-resistance steps: the presence of a randomized control arm over a single arm, and blinded outcome measurement. Change in each endpoint was quantified using a standardized effect size (Cohen's d). We conducted separate meta-analyses for each variable in turn, stratified by trial quality. In non-randomized, non-blinded studies, the majority of variables (10 of 12, 83%) showed significant improvement, ranging from a standardized mean effect size of +1.57 (95%CI +0.43 to +2.7) for ejection fraction to +2.87 (+1.78 to +3.95) for NYHA class. In the randomized, non-blinded study, only 3 out of 6 variables (50%) showed improvement. For the randomized blinded studies, 0 out of 9 variables (0%) showed benefit, ranging from -0.04 (-0.31 to +0.22) for ejection fraction to -0.1 (-0.73 to +0.53) for 6-minute walk test., Conclusions: Differences in degrees of resistance to bias, rather than choice of endpoint, explain the variation between studies of CRT in narrow-QRS heart failure addressing physiological variables. When bias-resistance features are implemented, it becomes clear that these patients do not improve in any tested physiological variable. Guidance from studies without careful planning to resist bias may be far less useful than commonly perceived., (© 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Background: Isolation of the pulmonary veins (PVs) for the treatment of atrial fibrillation (AF) is often supplemented with linear lesions within the left atrium (LA). However, there are conflicting data on the effects of creating a roof line (RL) joining the superior PVs in paroxysmal atrial fibrillation (PAF)., Methods and Results: A cohort of 120 patients with drug-refractory PAF referred for ablation were prospectively randomized into 2 strategies: (1) PV isolation in combination with RL ablation (LA roof ablation [LARA]-1: 59 patients) or (2) PV isolation (LARA-2: 61 patients). Follow-up was performed at 1, 3, and 6 months after the procedure and every 6 months thereafter. After a 3-month blanking period, recurrence was defined as the ocurrence of any atrial tachyarrhythmia lasting ≥30 seconds. PV isolation was achieved in 89% and complete RL block in 81%. RF duration, fluoroscopy, and procedural times were slightly, but not significantly, longer in the LARA-1 group. After 15±10 months, there was no difference in the arrhythmia-free survival after a single AF ablation procedure (LARA-1: 59% vs. LARA-2: 56% at 12 months; log rank P=0.77). The achievement of complete RL block did not influence the results. The incidence of LA macroreentrant tachycardias was 5.1% in the LARA-1 group (n=3) versus 8.2% in the LARA-2 (n=5) (P=ns). Univariate analysis only identified AF duration as a covariate associated with arrhythmia recurrence (hazard ratio, 1.01 [95% confidence interval, 1.002 to 1.012]; P<0.01)., Conclusion: The linear block at the LA roof is not associated with an improved clinical outcome compared with PV isolation alone., Clinical Trial Registration Url: ClinicalTrials.gov. Unique identifier: NCT01203241., (© 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)