Clinical cardiac electrophysiology and heart failure: impact of electrical disorders and their treatment

Ageing of the population, life style and increased survival of patients with cardiovascular diseases has favoured the development of heart failure and made of it a growing epidemiological problem in developed countries. The understanding of the mechanisms of progression of this disease and the recent advances in medical therapy has improved symptoms and prognosis of these patients. However, the degree of disability, the impairment in quality of life and mortality rates of patients with advanced heart failure remain high. Despite appropriate treatment, progressive mechanical and electrical remodeling of the heart may occur, favouring the development of arrhythmias (increasing the risk of sudden death and development of atrial fibrillation) and conduction disturbances that will further complicate the course of this disease and the treatment of these patients. Up to one third of the patients with systolic heart failure, may present signs of intra-ventricular conduction delay manifested by a broad QRS complex on the electrocardiogram, which is considered a surrogate for electrical dyssynchrony. These ventricular conduction disturbances have proven to be associated to more advanced heart disease and a worse prognosis. They usually take the form of left bundle branch block and produce a dyssynchronous contraction that reduces myocardial efficiency, further impairing systolic and diastolic function and worsening mitral regurgitation

Magnetic Assisted Navigation in Electrophysiology and Cardiac Resynchronisation: A Review

Magnetic assisted navigation is a new innovation that may prove useful in catheter ablation of cardiac arrhythmias and cardiac resynchronization therapy. The ability to steer extremely floppy catheters and guidewires may allow for these to be positioned safely in previously inaccessible areas of the heart. The integration of other new technology, such as image integration and electroanatomic mapping systems, should advance our abilities further. Although studies have shown the technology to be feasible, with the advantage to the physician of decreased radiation exposure, studies need to be performed to show additional benefit over standard techniques

New-onset atrial fibrillation is an independent predictor of in-hospital mortality in hospitalized heart failure patients: results of the EuroHeart Failure Survey

Aims The prognostic significance of atrial fibrillation (AF) in hospitalized patients with heart failure (HF) remains poorly understood. To evaluate in what way AF and its different modes of presentation affect the in-hospital mortality in patients admitted with HF. Methods and results The EuroHeart Failure Survey was conducted to ascertain how hospitalized HF patients are managed in Europe. The survey enrolled patients over a 6-week period in 115 hospitals from 24 countries. For this analysis, patients were categorized into three groups according to the type of AF, previous AF (patients known to have had AF prior to admission), new-onset AF (no previous AF with AF diagnosed during hospitalization), and no AF (no previous AF and no AF during hospitalization). Clinical variables, duration of hospitalization, and in-hospital survival status were assessed and compared among groups. Of the 10 701 patients included in the survey; 6027 (57%) had no AF, 3673 (34%) had previous AF, and 1001 (9%) had new-onset AF. Patients with new-onset AF had a longer stay in the intensive care unit (ICU) when compared with previous AF and no AF patients (mean 2.6 ± 5.3, 1.2 ± 3.5, and 1.5 ± 4.1 days, respectively; P < 0.001). In-hospital mortality was higher among patients with new-onset AF when compared with previous AF or no AF patients (12, 7, and 7% respectively; P < 0.001). After adjusting for multiple clinical variables, new-onset AF (not previous AF) was an independent predictor of in-hospital mortality (odds ratio 1.53, 95% CI 1.1-2.0). Conclusion In hospitalized patients with HF, new-onset AF is an independent predictor of in-hospital mortality and a longer ICU and hospital sta

Electro-anatomical mapping of the left atrium before and after cryothermal balloon isolation of the pulmonary veins

Introduction: The 28 mm cryoballoon catheter is a device used for pulmonary vein isolation (PVI). The aim of this study was to evaluate the extent of the ablation in the antral regions of the left atrium. Methods and Results: Eighteen patients with drug refractory, symptomatic, paroxysmal AF were enrolled. A 3D electroanatomic reconstruction of the left atrium was made before and after successful PVI with the 28 mm cryoballoon. Markers were placed at the ostium. Sixteen patients were mapped. Fourteen patients had 4 veins each, and 2 patients had a common ostium of the left sided veins. All separate ostia were isolated in the antral region. The two common ostia showed ostial isolation. There was a significant difference in vein size between the common (29 and 31 mm) and the separate ostia (19∈±∈4 mm) (p∈<∈0.01). The performance of an additional segmental ablation if balloon PVI did not eliminate all electrical activity, did not influence the extent of the ablation. The earliest left atrial activation during sinus rhythm was located in the superior septal region before ablation in all patients. After ablation, two patients showed a substantial downward shift towards the middle and inferior septal region respectively (NS). Four patients demonstrated a slight downward shift of the first activation. Conclusions: In cryoballoon PVI, the majority of the veins undergo antral isolation. Veins with a diameter larger than the balloon, are isolated ostially. In individual cases, the left atrial activation sequence appears to be altered after ablation

EuroEco (European Health Economic Trial on Home Monitoring in ICD Patients): a provider perspective in five European countries on costs and net financial impact of follow-up with or without remote monitoring

Aim: Remote follow-up (FU) of implantable cardiac defibrillators (ICDs) allows for fewer in-office visits in combination with earlier detection of relevant findings. Its implementation requires investment and reorganization of care. Providers (physicians or hospitals) are unsure about the financial impact. The primary end-point of this randomized prospective multicentre health economic trial was the total FU-related cost for providers, comparing Home Monitoring facilitated FU (HM ON) to regular in-office FU (HM OFF) during the first 2 years after ICD implantation. Also the net financial impact on providers (taking national reimbursement into account) and costs from a healthcare payer perspective were evaluated. Methods and results: Atotal of 312 patients with VVI-or DDD-ICD implants from 17 centres in six EU countries were randomised to HMON or OFF, of which 303 were eligible for data analysis. For all contacts (in-office, calendar-or alert-triggered web-based review, discussions, calls) time-expenditure was tracked. Country-specific cost parameters were used to convert resource use into monetary values. Remote FU equipment itself was not included in the cost calculations. Given only two patients from Finland (one in each group) a monetary valuation analysis was not performed for Finland. Average age was 62.4 +/- 13.1 years, 81% were male, 39% received a DDD system, and 51% had a prophylactic ICD. Resource use with HM ON was clearly different: less FU visits (3.79 +/- 1.67 vs. 5.53 +/- 2.32; P < 0.001) despite a small increase of unscheduled visits (0.95 +/- 1.50 vs. 0.62 +/- 1.25; P < 0.005), more non-office-based contacts (1.95+3.29 vs. 1.01 +/- 2.64; P < 0.001), more Internet sessions (11.02 +/- 15.28 vs. 0.06 +/- 0.31; P < 0.001) and more in-clinic discussions (1.84 +/- 4.20 vs. 1.28 +/- 2.92; P < 0.03), but with numerically fewer hospitalizations (0.67 +/- 1.18 vs. 0.85 +/- 1.43, P = 0.23) and shorter length-of-stay (6.31 +/- 15.5 vs. 8.26 +/- 18.6; P = 0.27), although not significant. For the whole study population, the total FU cost for providers was not different for HM ON vs. OFF [mean (95% CI): (sic)204 169-238) vs. (sic)213 (182-243); range for difference ((sic)-36 to 54), NS]. From a payer perspective, FU-related costs were similar while the total cost per patient (including other physician visits, examinations, and hospitalizations) was numerically (but not significantly) lower. There was no difference in the net financial impact on providers [profit of (sic)408 (327-489) vs. (sic)400 (345-455); range for difference ((sic)-104 to 88), NS], but there was heterogeneity among countries, with less profit for providers in the absence of specific remote FU reimbursement (Belgium, Spain, and the Netherlands) and maintained or increased profit in cases where such reimbursement exists (Germany and UK). Quality of life (SF-36) was not different. Conclusion: For all the patients as a whole, FU-related costs for providers are not different for remote FU vs. purely in-office FU, despite reorganized care. However, disparity in the impact on provider budget among different countries illustrates the need for proper reimbursement to ensure effective remote FU implementation

Predicting Early Mortality Among Implantable Defibrillator Patients Treated With Cardiac Resynchronization Therapy

Background: The beneficial effects of a cardiac resynchronization defibrillator (CRT-D) in patients with heart failure, low left ventricular ejection fraction (LVEF), and wide QRS have clearly been established. Nevertheless, mortality r

Prevention of inappropriate therapy in implantable defibrillators: a meta-analysis of clinical trials comparing single-chamber and dual-chamber arrhythmia discrimination algorithms

Introduction: A proposed benefit of dual-chamber arrhythmia discrimination is a reduction in inappropriate therapy in implantable cardioverter-defibrillators (ICDs). The aim of this meta-analysis was to establish whether dual-chamber arrhythmia discrimination algorithms reduce inappropriate device therapy. Methods and results: Public domain databases, MEDLINE, EMBASE, and Cochrane Register of Controlled Trials, were searched from 1996 to 2006. Two investigators abstracted data independently. Pooled estimates were calculated using both fixed-effects and random-effects models. We retrieved 5 prospective studies comparing dual-chamber with single-chamber arrhythmia discrimination, accumulating data on 748 patients. Pooled per-patient based analysis demonstrated that the number of patients receiving inappropriate ICD therapy was not different between single- and dual-chamber devices (odds ratio [OR] 1.23; 95% CI, 0.83 to 1.81; p=0.31). Per-episode based analysis demonstrated a favoring benefit for dual-chamber arrhythmia discrimination (ORO.64; 95% CI, 0.52 to 0.78; p < 0.001). A mean reduction of 1.1 inappropriately treated atrial episodes per patient was observed with dual-chamber arrhythmia discrimination (p < 0.001). Conclusions: Dual-chamber arrhythmia discrimination is associated with a reduction in the number of inappropriate treated episodes. The number of patients who experience inappropriate therapy is not reduced by dual-chamber discrimination. (c) 2007 Elsevier Ireland Ltd. All rights reserved

A grateful heart

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