• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• neurologie

Three-dimensional electrogram was used for analysis of ischemia manifestation in isolated hearts. Three parameters based on spherical coordination system were used in this study – amplitude of electrical heart vector, its azimuth and elevation. The parameters were presented as a trend. This approach reflected ischemic changes in a manner which can be easily observed and evaluated. Ischemia was analysed in seven isolated hearts of New Zealand white rabbits. It was found that (a) ischemia changes heart electric vector, (b) ischemic preconditioning has a protective effect, and (c) both of these findings can be clearly observed by the proposed method.

• MeSH
• akční potenciály MeSH
• elektrofyziologické techniky kardiologické MeSH
• financování organizované MeSH
• interpretace obrazu počítačem MeSH
• ischemická choroba srdeční diagnóza   prevence a kontrola   MeSH
• ischemické přivykání MeSH
• králíci MeSH
• modely kardiovaskulární MeSH
• modely nemocí na zvířatech MeSH
• prediktivní hodnota testů MeSH
• vektorkardiografie MeSH
• zobrazování trojrozměrné MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• zvířata MeSH
• Publikační typ
• přehledy MeSH

Measures from the theory of nonlinear dynamics were applied on complex fractionated atrial electrograms (CFAEs) in order to characterize their physiological dynamic behavior. The results were obtained considering 113 short term atrial electrograms (A-EGMs) which were annotated by three experts into four classes of fractionation according to A-EGMs signal regularity. The following measures were applied on A-EGM signals: General Correlation Dimension, Approximate Entropy, Detrended Fluctuation Analysis, Lempel-Ziv Complexity, and Katz-Sevcik, Variance and Box Counting Fractal Dimension. Assessment of disorganization was evaluated by a Kruskal Wallis statistical test. Except Detrended Fluctuation Analysis and Variance Fractal Dimension, the CFAE disorganization was found statistically significant even for low significant level alpha = 0.001. Moreover, the increasing complexity of A-EGM signals was reflected by higher values of General Correlation Dimension of order 1 and Approximate Entropy.

• MeSH
• algoritmy MeSH
• analýza rozptylu MeSH
• automatizace metody   MeSH
• elektrokardiografie metody   MeSH
• entropie MeSH
• fibrilace síní patofyziologie   MeSH
• fraktály MeSH
• lidé MeSH
• srdeční síně patofyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Considerable proportion of patients does not respond to the cardiac resynchronization therapy (CRT). This study investigated clinical relevance of left ventricular electrode local electrogram delay from the beginning of QRS (QLV). We hypothesized that longer QLV indicating more optimal lead placement in the late activated regions is associated with the higher probability of positive CRT response. METHODS: We conducted a retrospective, single-centre analysis of 161 consecutive patients with heart failure and LBBB or nonspecific intraventricular conduction delay (IVCD) treated with CRT. We routinely intend to implant the LV lead in a region with long QLV. Clinical response to CRT, left ventricular (LV) reverse remodelling (i.e. decrease in LV end-systolic diameter - LVESD ≥10%) and reduction in plasma level of NT-proBNP >30% at 12-month post-implant were the study endpoints. We analyzed association between pre-implant variables and the study endpoints. RESULTS: Clinical CRT response rate reached 58%, 84% and 92% in the lowest (≤105 ms), middle (106-130 ms) and the highest (>130 ms) QLV tertile (p < 0.0001), respectively. Longer QRS duration (p = 0.002), smaller LVESD and a non-ischemic cardiomyopathy (both p = 0.02) were also univariately associated with positive clinical CRT response. In a multivariate analysis, QLV remained the strongest predictor of clinical CRT response (p < 0.00001), followed by LVESD (p = 0.01) and etiology of LV dysfunction (p = 0.04). Comparable predictive power of QLV for LV reverse remodelling and NT-proBNP response rates was observed. CONCLUSION: LV lead position assessed by duration of the QLV interval was found the strongest independent predictor of beneficial clinical response to CRT.

• MeSH
• biologické markery krev   MeSH
• blokáda Tawarova raménka patofyziologie   terapie   MeSH
• časové faktory MeSH
• design vybavení MeSH
• dospělí MeSH
• elektrofyziologické techniky kardiologické * MeSH
• funkce levé komory srdeční * MeSH
• hodnocení rizik MeSH
• lidé středního věku MeSH
• lidé MeSH
• lineární modely MeSH
• multivariační analýza MeSH
• natriuretický peptid typu B krev   MeSH
• peptidové fragmenty krev   MeSH
• prediktivní hodnota testů MeSH
• prostředky srdeční resynchronizační terapie * MeSH
• remodelace komor MeSH
• retrospektivní studie MeSH
• rizikové faktory MeSH
• rozdělení chí kvadrát MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• srdeční blokáda krev   patofyziologie   terapie   MeSH
• srdeční resynchronizační terapie * škodlivé účinky   MeSH
• srdeční selhání krev   patofyziologie   terapie   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH

Most cardiac arrhythmias can be classified as atrial flutter, focal atrial tachycardia, or atrial fibrillation. They have been usually treated using drugs, but catheter ablation has proven more effective. This is an invasive method devised to destroy the heart tissue that disturbs correct heart rhythm. In order to accurately localise the focus of this disturbance, the acquisition and processing of atrial electrograms form the usual mapping technique. They can be single potentials, double potentials, or complex fractionated atrial electrogram (CFAE) potentials, and last ones are the most effective targets for ablation. The electrophysiological substrate is then localised by a suitable signal processing method. Sample Entropy is a statistic scarcely applied to electrograms but can arguably become a powerful tool to analyse these time series, supported by its results in other similar biomedical applications. However, the lack of an analysis of its dependence on the perturbations usually found in electrogram data, such as missing samples or spikes, is even more marked. This paper applied SampEn to the segmentation between non-CFAE and CFAE records and assessed its class segmentation power loss at different levels of these perturbations. The results confirmed that SampEn was able to significantly distinguish between non-CFAE and CFAE records, even under very unfavourable conditions, such as 50% of missing data or 10% of spikes.

• MeSH
• elektrofyziologické techniky kardiologické * MeSH
• entropie * MeSH
• fibrilace síní diagnóza   MeSH
• katetrizační ablace MeSH
• lidé MeSH
• srdeční elektrofyziologie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• chybná zdravotní péče MeSH
• defibrilátory implantabilní škodlivé účinky   MeSH
• elektrická stimulace MeSH
• elektrofyziologické techniky kardiologické metody   MeSH
• finanční podpora výzkumu jako téma MeSH
• implantované elektrody MeSH
• modely u zvířat MeSH
• oscilometrie metody   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH

• MeSH
• atrioventrikulární nodální reentry tachykardie * chirurgie   MeSH
• elektrofyziologické techniky kardiologické MeSH
• katetrizační ablace * MeSH
• lidé středního věku MeSH
• lidé MeSH
• peroperační komplikace * prevence a kontrola   MeSH
• retrospektivní studie MeSH
• spektrální analýza * statistika a číselné údaje   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH

• MeSH
• experimenty na zvířatech MeSH
• financování organizované MeSH
• koronární bypass metody   trendy   využití   MeSH
• počítačové zpracování signálu MeSH
• psi MeSH
• revaskularizace myokardu metody   využití   MeSH
• srdeční elektrofyziologie metody   přístrojové vybavení   trendy   MeSH
• statistika jako téma MeSH
• Check Tag
• psi MeSH

BACKGROUND: Cryoballoon ablation for treatment of atrial fibrillation (AF) reduces procedure times, but limited data is available about its impact on electrophysiology (EP) lab efficiency in Central and Eastern Europe (CEE). Using CEE-specific procedure data, the present study modeled cryoballoon ablation procedures on EP lab resource consumption to improve efficiency. METHODS: A discrete event simulation model was developed to assess EP efficiency with cryoballoon ablation. Model inputs were taken from CEE sites within the Cryo Global Registry, namely Czech Republic, Hungary, Poland, Serbia, and Slovakia. The main endpoints were percentage of days that resulted in overtime and percentage of days with time for one extra simple EP procedure. Use of the 'figure of 8' (Fo8) closure technique to reduce procedure time was also examined. RESULTS: The mean lab occupancy time across all CEE sites was 133 ± 47 minutes (min: 104 minutes, max:181 minutes). Cryoballoon ablation in the base-case scenario resulted in 14.6% of days with overtime and 64.8% of days with time for an extra simple EP procedure. Use of the Fo8 closure technique enhanced these values to 5.5% and 85.3%, respectively. Model endpoints were most sensitive to changes in lab occupancy times and overtime start time. CONCLUSIONS: In this CEE-specific analysis of EP lab efficiency it was found that 3 cryoballoon ablation procedures could be performed in 1 lab day, leaving time for a 4th simple EP procedure on most days. As such, use cryoballoon ablation for PVI is an effective way to improve EP lab efficiency.

• MeSH
• časové faktory MeSH
• délka operace MeSH
• elektrofyziologické techniky kardiologické MeSH
• fibrilace síní * chirurgie   patofyziologie   diagnóza   MeSH
• kryochirurgie * MeSH
• lidé MeSH
• registrace * MeSH
• venae pulmonales * chirurgie   patofyziologie   MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• Geografické názvy
• východní Evropa MeSH