Calvo, M.; Hernández-Rodríguez, J.; Vidorreta, S.; Brugada, J.; Gomis, P.; Arbelo, E. Europace Vol. 19, num. Supp 3, p. iii347 DOI: 10.1093/ehjci/eux158.246 Data de publicació: 2017-06-20 Article en revista
Background: As described in the literature, Brugada syndrome (BrS) patients presenting a spontaneous type 1 electrocardiographic (ECG) pattern are related to a greater arrhythmic risk compared to those with a flecainideinduced type 1 ECG pattern. The 24hour continuous ECG provides relevant cardiac information. However, it is usually challenging and time consuming to analyze.
Purpose: This work presents an automatic algorithm able to detect significant ECG parameters in the disease, such as Brugada-like pattern burden on ECG monitoring.
Methods: The algorithm integrates a previously developed and validated ECG delineator in order to locate the beginning, peak and ending of cardiac waves. Then, it classifies each beat between normal or Brugada-like, based on the morphology of the detected waves (see table below). Likewise, the algorithm includes the detection of other relevant ECG features: STsegment elevation, PR, QRS and QTc intervals duration, heart rate variability and number of premature ventricular contractions, among others. Validation of the Brugada-pattern detector was done by assessment of the beat-to-beat correlation of the 24hour 12lead ECG signals in 2 BrS patients with spontaneous type 1 ECG and 1 healthy individual, 2 blinded arrhythmia specialists.
Results: From a random sample of 212 beats, type 1 ECG pattern was correctly detected in the 98.11% of beats in V1, 84.91% in V2, 92.45% in aVR and 100% in aVF. Erroneous detections mainly resulted from incorrect Twave delineations in noisy segments. Regarding type 2 ECG detections, all analyzed beats in V1 and the 92.45% in V2 were properly classified.
Conclusion: This study shows the feasibility of the algorithm to automatically detect Brugada-like beats on a 24hour continuous ECG monitoring. Future work will be focused on testing the performed detector in an extensive sample of patients diagnosed with BrS that, based on their cardiac events, will allow to determine the association of this ECG parameter burden with the individual risk of suffering sudden cardiac death.
Stockburger, M.; Eduardo, D.; Lamas, G.; desaga, M.; Koening, C.; Habedank, D.; Cobo, E.; Navarro, X.; Wiegand, U. Europace Vol. 16, num. 1, p. 63-70 DOI: 10.1093/europace/eut217 Data de publicació: 2014-01-01 Article en revista
Aims Previous studies showed unfavourable effects of right ventricular (RV) pacing. Ventricular pacing (VP), however, is required in many patients with atrioventricular (AV) block. The PREVENT-HF study explored left ventricular (LV) remodelling during RV vs. biventricular (BIV) pacing in AV block without advanced heart failure. The pre-specified PREVENT-HF German Substudy examined exercise capacity and N-terminal pro-brain natriuretic peptide (NT-proBNP).; Methods and results Patients with expected VP >= 80% were randomized to RV or BIV pacing. Endpoints were peak oxygen uptake (pVO(2)), oxygen uptake at the anaerobic threshold (VO(2)AT), ventilatory efficiency (VE/VCO2), and logNT-proBNP. Considering crossover, intention to treat (ITT), and on-treatment (OT) analyses of covariance (ANCOVA) were performed. For exercise testing 44 (RV: 25, BIV: 19), and for NT-proBNP 53 patients (RV: 29, BIV: 24) were included. The ITT analysis revealed significant differences in pVO(2) [ANCOVA effect 2.83 mL/kg/min, confidence interval (CI) 0.83-4.91, P = 0.007], VO(2)AT (ANCOVA effect 2.14 mL/min/k, CI 0.14-4.15, P = 0.03), and VE/VCO2 (ANCOVA effect -5.46, CI -10.79 to -0.13, P = 0.04) favouring BIV randomization. The significant advantage in pVO(2) persisted in OT analysis, while VO(2)AT and VE/VCO2 showed trends favouring BIV pacing. LogNT-proBNP did not differ between groups. (ITT:ANCOVA effect 0.008, CI -0.40 to +0.41, P = 0.97; OT: ANCOVA effect -0.03, CI -0.44 to 0.30, P = 0.90).; Conclusion Our study suggests that BIV pacing produces better exercise capacity over 1 year compared with RV pacing in patients without advanced heart failure and AV block. In contrast, we observed no significant changes of NT-proBNP. Larger trials will allow appraising the clinical usefulness of BIV pacing in AV block.
Aims This randomized trial evaluated clinically significant adverse events (CSAEs), in patients implanted with dual-chamber (DC) vs. single-chamber (SC) implantable cardioverter defibrillator (ICD). DC-ICD had atrial tachyarrhythmia (AT) therapy capabilities. Strict programming recommendations were reinforced.
Methods and results Patients with conventional SC-ICD indication were randomized to DC-ICD, SC-ICD, or a DC-ICD programmed as an SC-ICD (SC-simulated) and followed for 16 months. Patients in the DC and SC-simulated groups crossed over after 8 months. The primary endpoint was a composite of CSAE: all-cause mortality; invasive intervention; hospitalization (>24 h) for cardiovascular causes; inappropriate shocks (two or more episodes); and sustained symptomatic AT lasting >48 h. The outcome variable was a pre-specified score that corrected for clinical severity and follow-up duration. Three hundred and thirty-four patients were analysed (DC-ICD, n = 112; SC-ICD, n = 111; SC-simulated, n = 111). The mean left ventricular ejection fraction was 0.36 ± 0.13, 69% were in functional class =II. CSAE occurred in 65 DC-ICD, 82 SC-ICD, and 84 SC-simulated patients. The outcome variable was 33% lower in the DC-ICD group (OR 0.31; 95% CI 0.14–0.67; P = 0.0028). Mortality was 4% in DC, 9% in SC, and 10% in SC-simulated.
Conclusion In patients with a standard SC-ICD indication, DC-ICD was associated with less CSAE when compared with SC-ICD.
Mont, L.; Ruiz, R.; Martínez, J.; Carmona, J.; Fidalgo, M.; Cobo, E.; Riera, M.; Navarro, X. Europace Vol. 10, num. 1, p. 28-34 DOI: 10.1093/europace/eum268 Data de publicació: 2008-01 Article en revista
Single chamber (SC) implantable cardioverter defibrillators (ICDs) have several limitations that might be relevant during follow-up, like atrial pacing requirements, inadequate therapies, sustained atrial tachyarrhythmias and difficulties to achieve an accurate diagnosis of the arrhythmia. Dual chamber (DC) ICDs offer an attractive and rational solution, although controversy remains if the costs and complexity of these devices offer a real clinical advantage. The Dual Chamber & Atrial Tachyarrhythmias Adverse Events Study (DATAS) was designed to analyze the ability of DC ICD, DDED, to reduce clinically significant adverse events compared with SC ICD in a non-selected population with conventional indications for ICD implantation. This is a prospective, multicentre, randomized, open labelled study, with three arms: two of them (simulated SC ICD and true DC ICD) cross-over, and the third (true SC ICD) parallels the other two. The composite primary end point comprises four Clinically Significant Adverse Events (CSAE): (1) all-cause mortality, (2) invasive intervention, hospitalization or prolongation of hospitalization due to cardiovascular cause, (3) inappropriate shocks, and (4) sustained symptomatic atrial tachyarrhythmias that (a) require urgent termination or (b) last more than 48¿h leading to therapeutic intervention. Secondary end points constitute each of the individual components of CSAE, cardiovascular status, quality of life and a detailed analysis of atrial and ventricular arrhythmias. To date (June 2003) there have been 343 patients enroled from 947 screened patients. The projected enrolment includes 360 patients and the conclusion of the study is expected at the beginning of 2005.