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Elektrokardiografi är en vanligt förekommande undersökning inom hälso- och sjukvården då undersökningen är icke-invasiv och ger en bra överblick över hjärtats elektrofysiologiska status. Ett vanligt fel vid EKG är elektrodplacering i andra respektive tredje intercostala utrymmet istället för i fjärde intercostala utrymmet (IC4), vilket bland annat kan medföra reducering av R-vågs amplituden samt påverka datortolkningen. Syftet med arbetet var att se om avvikande EKG-kurvor uppstår vid omplacering av elektroderna V1 och V2 i andra och tredje intercostala utrymmet vid jämförelse med fjärde intercostala utrymmet på friska vuxna. I studien ingår 50 deltagare i åldern 18-48. Den statistiska analysen utfördes med hjälp av parvis T-test samt Fisher exact test. Jämförelsen mellan de olika placeringarna resulterade i en signifikant minskning av R-vågsamplituden (p <0,001) för samtliga kombinationer. En signifikant minskning visades i R-vågsduration i jämförelsen Intercostalrum 2 (IC2) versus (vs) IC4 i V2. För ST-sträckan visade båda avledningarna för jämförelsen IC2 vs IC4 en signifikant skillnad (p<0,001). Datortolkningen visade en signifikant skillnad för IC2 vs IC4 (p0,006) samt IC3 vs IC4 (p<0,001). Omplacering av elektroder medför förändrad datortolkning när det vid en standardplacering visar ett normalt EKG, vilket kan ge en inverkan på patientens fortsatta handläggning och eventuella diagnos., Electrocardiography is commonly used in healthcare as the examination is non-invasive and provides a good overview of the heart's electrophysiological status. A common error in ECG positioning is placement in the second or third intercostal space, which among other things can lead to a reduction in R wave amplitude and affect the computer interpretation. The aim of the study is to see if deviant ECG curves occur when repositioning the electrodes V1 and V2 in the second and third intercostal space when compared to the fourth intercostal space. The study includes 50 healthy adults aged 18-48. The statistical analysis was performed using paired t tests and Fisher exact test. The comparison resulted in a significant reduction in R wave amplitude (p <0.001) for all combinations. A significant decrease was shown in R wave duration in the comparison of IC2 vs IC4 in V2. For the ST segment, both leads for the comparison IC4 vs IC2 a significant difference was presented (p <0.001). For the computer interpretation, a significant difference was shown for IC2 vs IC4 (p0.006) and IC3 vs IC4 (p<0.001). Repositioning of electrodes leads to a different computer interpretation when in standard positioning shows a normal ECG, which may lead to misdiagnosis.

Elektrokardiografi är en vanligt förekommande undersökning inom hälso- och sjukvården då undersökningen är icke-invasiv och ger en bra överblick över hjärtats elektrofysiologiska status. Ett vanligt fel vid EKG är elektrodplacering i andra respektive tredje intercostala utrymmet istället för i fjärde intercostala utrymmet (IC4), vilket bland annat kan medföra reducering av R-vågs amplituden samt påverka datortolkningen. Syftet med arbetet var att se om avvikande EKG-kurvor uppstår vid omplacering av elektroderna V1 och V2 i andra och tredje intercostala utrymmet vid jämförelse med fjärde intercostala utrymmet på friska vuxna. I studien ingår 50 deltagare i åldern 18-48. Den statistiska analysen utfördes med hjälp av parvis T-test samt Fisher exact test. Jämförelsen mellan de olika placeringarna resulterade i en signifikant minskning av R-vågsamplituden (p <0,001) för samtliga kombinationer. En signifikant minskning visades i R-vågsduration i jämförelsen Intercostalrum 2 (IC2) versus (vs) IC4 i V2. För ST-sträckan visade båda avledningarna för jämförelsen IC2 vs IC4 en signifikant skillnad (p<0,001). Datortolkningen visade en signifikant skillnad för IC2 vs IC4 (p0,006) samt IC3 vs IC4 (p<0,001). Omplacering av elektroder medför förändrad datortolkning när det vid en standardplacering visar ett normalt EKG, vilket kan ge en inverkan på patientens fortsatta handläggning och eventuella diagnos., Electrocardiography is commonly used in healthcare as the examination is non-invasive and provides a good overview of the heart's electrophysiological status. A common error in ECG positioning is placement in the second or third intercostal space, which among other things can lead to a reduction in R wave amplitude and affect the computer interpretation. The aim of the study is to see if deviant ECG curves occur when repositioning the electrodes V1 and V2 in the second and third intercostal space when compared to the fourth intercostal space. The study includes 50 healthy adults aged 18-48. The statistical analysis was performed using paired t tests and Fisher exact test. The comparison resulted in a significant reduction in R wave amplitude (p <0.001) for all combinations. A significant decrease was shown in R wave duration in the comparison of IC2 vs IC4 in V2. For the ST segment, both leads for the comparison IC4 vs IC2 a significant difference was presented (p <0.001). For the computer interpretation, a significant difference was shown for IC2 vs IC4 (p0.006) and IC3 vs IC4 (p<0.001). Repositioning of electrodes leads to a different computer interpretation when in standard positioning shows a normal ECG, which may lead to misdiagnosis.

The paper presents a low complexity algorithm for extracting features of an electrocardiogram (QRS complex, P wave and T wave). A low power and resource optimal architecture is designed to implement this algorithm efficiently. The algorithm's parameters are chosen appropriately to avoid any floating-point compute-intensive arithmetic operation enabling us to implement it using comparators, shifters and adders only, which leads to efficient hardware resource utilization. The proposed architecture employs techniques such as clock gating to optimize power consumption. The modules delineating different peaks and boundaries of the ECG signal can be turned off when they are not operational or as per the medical requirements. The algorithm and architecture proposed in this paper are validated using MIT-BIH and QT database from Physionet. The proposed algorithm is implemented using the Virtex - 7 FPGA platform with average resource utilization of 0.42%, which is the least compared to other methods. The implementation is synthesized using 180 nm CMOS technology. The proposed design utilizes 7.38 mu W and 7.38 pJ of power and energy respectively, at an operating frequency of 1 MHz at 1.98 V. The energy consumption of the proposed architecture is reduced by factor of 1.28 compared to other known methods due to minimal utilization of Flip-Flops and LUTs. Therefore, our architecture can be efficiently deployed in low power and resource-constrained wearable healthcare applications., Článek představuje algoritmus s nízkou složitostí pro extrakci vlastností elektrokardiogramu (QRS komplex, vlna P a vlna T). Pro efektivní implementaci tohoto algoritmu je navržena architektura s nízkou spotřebou energie a optimálními zdroji. Parametry algoritmu jsou vhodně zvoleny tak, aby se vyhnuly jakýmkoli aritmetickým operacím náročným na výpočty v plovoucí řádové čárce, což nám umožňuje implementovat jej pouze pomocí komparátorů, posunovačů a sčítačů, což vede k efektivnímu využití hardwarových prostředků. Navržená architektura využívá techniky, jako je taktování, k optimalizaci spotřeby energie. Moduly vymezující různé špičky a hranice EKG signálu lze vypnout, pokud nejsou v činnosti nebo podle lékařských požadavků. Algoritmus a architektura navržené v tomto článku jsou ověřeny pomocí databáze MIT-BIH a QT z Physionet. Navržený algoritmus je implementován na platformě Virtex - 7 FPGA s průměrným využitím prostředků 0,42 %, což je nejméně ve srovnání s jinými metodami. Implementace je syntetizována pomocí 180 nm technologie CMOS. Navržený návrh využívá 7,38 mu W, respektive 7,38 pJ výkonu a energie při pracovní frekvenci 1 MHz a napětí 1,98 V. Spotřeba energie navržené architektury je ve srovnání s ostatními známými metodami snížena o faktor 1,28 díky minimálnímu využití Flip-Flops a LUT. Proto lze naši architekturu efektivně nasadit v aplikacích nositelné zdravotní péče s nízkou spotřebou energie a omezenými zdroji.

Background: Long QT syndromes (LQTS) arise from many genetic and nongenetic causes with certain characteristic ECG features preceding polymorphic ventricular tachyarrhythmias (PVTs). However, how the many molecular causes result in these characteristic ECG patterns and how these patterns are mechanistically linked to the spontaneous initiation of PVT remain poorly understood. Methods: Anatomic human ventricle and simplified tissue models were used to investigate the mechanisms of spontaneous initiation of PVT in LQTS. Results: Spontaneous initiation of PVT was elicited by gradually ramping up ICa,L to simulate the initial phase of a sympathetic surge or by changing the heart rate, reproducing the different genotype-dependent clinical ECG features. In LQTS type 2 (LQT2) and LQTS type 3 (LQT3), T-wave alternans was observed followed by premature ventricular complexes (PVCs). Compensatory pauses occurred resulting in short-long-short sequences. As ICa,L increased further, PVT episodes occurred, always preceded by a short-long-short sequence. However, in LQTS type 1 (LQT1), once a PVC occurred, it always immediately led to an episode of PVT. Arrhythmias in LQT2 and LQT3 were bradycardia dependent, whereas those in LQT1 were not. In all 3 genotypes, PVCs always originated spontaneously from the steep repolarization gradient region and manifested on ECG as R-on-T. We call this mechanism R-from-T, to distinguish it from the classic explanation of R-on-T arrhythmogenesis in which an exogenous PVC coincidentally encounters a repolarizing region. In R-from-T, the PVC and the T wave are causally related, where steep repolarization gradients combined with enhanced ICa,L lead to PVCs emerging from the T wave. Since enhanced ICa,L was required for R-from-T to occur, suppressing window ICa,L effectively prevented arrhythmias in all 3 genotypes. Conclusions: Despite the complex molecular causes, these results suggest that R-from-T is likely a common mechanism for PVT initiation in

Coronary perforations are a rare but potentially catastrophic complication of percutaneous coronary intervention. We report a rare case of a large cavity-spilling perforation from the left anterior descending coronary artery into the left ventricle, which was successfully treated with a covered stent. However, repeating angiography 1 week later demonstrated persistence of the perforation due to stent malapposition.Copyright © 2015, Japanese Association of Cardiovascular Intervention and Therapeutics.

Coronary perforations are a rare but potentially catastrophic complication of percutaneous coronary intervention. We report a rare case of a large cavity-spilling perforation from the left anterior descending coronary artery into the left ventricle, which was successfully treated with a covered stent. However, repeating angiography 1 week later demonstrated persistence of the perforation due to stent malapposition.Copyright © 2015, Japanese Association of Cardiovascular Intervention and Therapeutics.

BackgroundT-peak to T-end interval (Tp-e) is an independent marker of sudden cardiac death. Modulation of Tp-e by sympathetic nerve activation and circulating norepinephrine is not well understood. The purpose of this study was to characterize endocardial and epicardial dispersion of repolarization (DOR) and its effects on Tp-e with sympathetic activation.Methods and resultsIn Yorkshire pigs (n=13), a sternotomy was performed and the heart and bilateral stellate ganglia were exposed. A 56-electrode sock and 64-electrode basket catheter were placed around the epicardium and in the left ventricle (LV), respectively. Activation recovery interval, DOR, defined as variance in repolarization time, and Tp-e were assessed before and after left, right, and bilateral stellate ganglia stimulation and norepinephrine infusion. LV endocardial and epicardial activation recovery intervals significantly decreased, and LV endocardial and epicardial DOR increased during sympathetic nerve stimulation. There were no LV epicardial versus endocardial differences in activation recovery interval during sympathetic stimulation, and regional endocardial activation recovery interval patterns were similar to the epicardium. Tp-e prolonged during left (from 40.4±2.2 ms to 92.4±12.4 ms; P<0.01), right (from 47.7±2.6 ms to 80.7±11.5 ms; P<0.01), and bilateral (from 47.5±2.8 ms to 78.1±9.8 ms; P<0.01) stellate stimulation and strongly correlated with whole heart DOR during stimulation (P<0.001, R=0.86). Of note, norepinephrine infusion did not increase DOR or Tp-e.ConclusionsRegional patterns of LV endocardial sympathetic innervation are similar to that of LV epicardium. Tp-e correlated with whole heart DOR during sympathetic nerve activation. Circulating norepinephrine did not affect DOR or Tp-e.

Background: Many newer cardiac implantable devices have remote monitoring capability. Remote monitoring reduces time to arrhythmia detection; reduces number of patient visits and is thought to be cost effective. Monash- Heart started remote monitoring of cardiac devices in 2009, presently has 612 device patients being remotely monitored. Remote monitoring devices included automatic wireless transmission and devices requiring manual interrogation. Method(s): Data was prospectively collected from June 2013 to October 2014. Automated arrhythmia alerts, technologist interpretation of these alerts, event to alert time, intervention provided in form of clinic visit/hospitalisation and adherence to remote monitoring (for wired telephone remote monitoring) were recorded and analysed. Result(s): Devices monitored included implantable cardiac defibrillators(ICD) 49%,Bi-ventricular-ICDs 14%, pacemakers 30% and implantable loop recorders 6% (ILD). A total of 275 events were reviewed by technologist and found to be ventricular tachycardia (n=140,50%); atrial fibrillation/ flutter (n=74,27%);T wave over-sensing (n=4,1%); lead . These numbers exclude false alerts from ILD, where frequent undersensing leading to false diagnosis of asystole(>3000 alerts/year from 40 ILDs). Average event to alert time was 0.77 days in devices with automatic transmission, 11.5 days for devices requiring manual interrogation. Conclusion(s): Remote monitoring of cardiac devices is feasible and leads to early detection of arrhythmia alerts. Longer arrhythmia detection times were seen in devices requiring manual interrogation. Most common artefact was under sensing-related asystole in implantable loop recorders. Device interpretation of alerts needs to be frequently reclassified by a trained technologist.

Background: Many newer cardiac implantable devices have remote monitoring capability. Remote monitoring reduces time to arrhythmia detection; reduces number of patient visits and is thought to be cost effective. Monash- Heart started remote monitoring of cardiac devices in 2009, presently has 612 device patients being remotely monitored. Remote monitoring devices included automatic wireless transmission and devices requiring manual interrogation. Method(s): Data was prospectively collected from June 2013 to October 2014. Automated arrhythmia alerts, technologist interpretation of these alerts, event to alert time, intervention provided in form of clinic visit/hospitalisation and adherence to remote monitoring (for wired telephone remote monitoring) were recorded and analysed. Result(s): Devices monitored included implantable cardiac defibrillators(ICD) 49%,Bi-ventricular-ICDs 14%, pacemakers 30% and implantable loop recorders 6% (ILD). A total of 275 events were reviewed by technologist and found to be ventricular tachycardia (n=140,50%); atrial fibrillation/ flutter (n=74,27%);T wave over-sensing (n=4,1%); lead . These numbers exclude false alerts from ILD, where frequent undersensing leading to false diagnosis of asystole(>3000 alerts/year from 40 ILDs). Average event to alert time was 0.77 days in devices with automatic transmission, 11.5 days for devices requiring manual interrogation. Conclusion(s): Remote monitoring of cardiac devices is feasible and leads to early detection of arrhythmia alerts. Longer arrhythmia detection times were seen in devices requiring manual interrogation. Most common artefact was under sensing-related asystole in implantable loop recorders. Device interpretation of alerts needs to be frequently reclassified by a trained technologist.

BackgroundT-peak to T-end interval (Tp-e) is an independent marker of sudden cardiac death. Modulation of Tp-e by sympathetic nerve activation and circulating norepinephrine is not well understood. The purpose of this study was to characterize endocardial and epicardial dispersion of repolarization (DOR) and its effects on Tp-e with sympathetic activation.Methods and resultsIn Yorkshire pigs (n=13), a sternotomy was performed and the heart and bilateral stellate ganglia were exposed. A 56-electrode sock and 64-electrode basket catheter were placed around the epicardium and in the left ventricle (LV), respectively. Activation recovery interval, DOR, defined as variance in repolarization time, and Tp-e were assessed before and after left, right, and bilateral stellate ganglia stimulation and norepinephrine infusion. LV endocardial and epicardial activation recovery intervals significantly decreased, and LV endocardial and epicardial DOR increased during sympathetic nerve stimulation. There were no LV epicardial versus endocardial differences in activation recovery interval during sympathetic stimulation, and regional endocardial activation recovery interval patterns were similar to the epicardium. Tp-e prolonged during left (from 40.4±2.2 ms to 92.4±12.4 ms; P<0.01), right (from 47.7±2.6 ms to 80.7±11.5 ms; P<0.01), and bilateral (from 47.5±2.8 ms to 78.1±9.8 ms; P<0.01) stellate stimulation and strongly correlated with whole heart DOR during stimulation (P<0.001, R=0.86). Of note, norepinephrine infusion did not increase DOR or Tp-e.ConclusionsRegional patterns of LV endocardial sympathetic innervation are similar to that of LV epicardium. Tp-e correlated with whole heart DOR during sympathetic nerve activation. Circulating norepinephrine did not affect DOR or Tp-e.

Background: Deregulated acetylation of histones plays a key role in the pathogenesis of haematological and solid tumors by changing the transcription of genes involved in cell cycle control, differentiation or apoptosis. Thus, there is considerable interest in HDAC inhibition as a potential therapeutic modality in the treatment of hematological and solid tumor malignancies, including pediatric malignancies. Method(s): This is an open label, Phase I, multi-centre study evaluating panobinostat in pediatric patients with refractory solid tumours. Primary endpoints were to define and describe associated toxicities, and to characterize its pharmacokinetics (PK). Secondary endpoints included assessing the anti-tumour activity of panobinostat, and also to assess its biologic activity by measuring the histone acetylation status in peripheral blood mononuclear cells (PBMNC). Result(s): Nine patients were enrolled and treated with intravenous panobinostat at a dosing level of 15mg/m2. Three patients were removed from study prior to completion of course one due to tumour progression. A dose of 15mg/m2 was tolerated with one dose limiting toxicity (DLT) observed in the six patients evaluated for DLT. Two (22%) patients experienced grade 3-4 thrombocytopenia, 1 (11%) experienced grade 3 anemia, and 2 (22%) experienced grade 3 neutropenia. Grade 4 drug related pain occurred in 2 (22%) of patients studied. Vomiting (44%), nausea (33%) and hypokalaemia (22%) were also common adverse events. Two (22%) of patients experienced a Grade II QTcF change (0.478 +/- 0.006 msec). One cardiac DLT (T wave changes) was reported. PK values for 15mg/m2 (n=9) dosing were: Tmax 0.8 hours, Cmax 235.2 ng/ml, AUC0-t 346.8h.ng/ml and t1/2 7.3 hours. Pooled flow cytometry results of all nine patient samples confirm that panobinostat significantly induced acetylation of histone H3 and H4 at 6 hours (p< 0.001), 24 hours (P<0.01) and 28-70 hours (p<0.05) post dose. Conclusion(s): A significant, sustained

Background: Deregulated acetylation of histones plays a key role in the pathogenesis of haematological and solid tumors by changing the transcription of genes involved in cell cycle control, differentiation or apoptosis. Thus, there is considerable interest in HDAC inhibition as a potential therapeutic modality in the treatment of hematological and solid tumor malignancies, including pediatric malignancies. Method(s): This is an open label, Phase I, multi-centre study evaluating panobinostat in pediatric patients with refractory solid tumours. Primary endpoints were to define and describe associated toxicities, and to characterize its pharmacokinetics (PK). Secondary endpoints included assessing the anti-tumour activity of panobinostat, and also to assess its biologic activity by measuring the histone acetylation status in peripheral blood mononuclear cells (PBMNC). Result(s): Nine patients were enrolled and treated with intravenous panobinostat at a dosing level of 15mg/m2. Three patients were removed from study prior to completion of course one due to tumour progression. A dose of 15mg/m2 was tolerated with one dose limiting toxicity (DLT) observed in the six patients evaluated for DLT. Two (22%) patients experienced grade 3-4 thrombocytopenia, 1 (11%) experienced grade 3 anemia, and 2 (22%) experienced grade 3 neutropenia. Grade 4 drug related pain occurred in 2 (22%) of patients studied. Vomiting (44%), nausea (33%) and hypokalaemia (22%) were also common adverse events. Two (22%) of patients experienced a Grade II QTcF change (0.478 +/- 0.006 msec). One cardiac DLT (T wave changes) was reported. PK values for 15mg/m2 (n=9) dosing were: Tmax 0.8 hours, Cmax 235.2 ng/ml, AUC0-t 346.8h.ng/ml and t1/2 7.3 hours. Pooled flow cytometry results of all nine patient samples confirm that panobinostat significantly induced acetylation of histone H3 and H4 at 6 hours (p< 0.001), 24 hours (P<0.01) and 28-70 hours (p<0.05) post dose. Conclusion(s): A significant, sustained

Sudden cardiac death (SCD) is a major medical and public health concern responsible for 50% of cardiovascular deaths and as much as 15% to 20% of overall mortality. Coronary heart disease is the underlying cause of most of these deaths, and in 50% of such cases, SCD is the first manifestation of the disease. Researchers have investigated numerous noninvasive methods to more accurately identify individuals at high risk of SCD, but most such studies have focused on patients with specific heart disease. The standard 12-lead electrocardiogram (ECG) is a widely available tool to analyze the electrical activity of the heart, but few epidemiological studies have successfully identified specific electrocardiographic risk markers of SCD at the population level. This thesis aims to clarify the prognostic implications of several ECG patterns in the general population. We evaluated the 12-lead ECGs of 10899 middle-aged Finnish subjects (52% male) recorded between 1966 and 1972, and followed the subjects for 30 ± 11 years. The prevalence of a prolonged QRS duration ≥ 110 ms and nonspecific intraventricular conduction delay (IVCD; defined as QRS ≥ 110 ms with no partial or complete bundle branch block) in the population was 1.3% and 0.6%, respectively. Both were significantly associated with an elevated risk of all-cause mortality and cardiovascular mortality. QRS duration ≥ 110 ms doubled the risk of SCD, and IVCD was associated with a three-fold higher risk of SCD. Two percent of the subjects presented with wide frontal QRS-T angle ≥ 100° (the angle between the QRS axis and the T-wave axis in the frontal plane). A wide QRS-T angle was associated with higher overall mortality and more than doubled the risk of SCD, which was mainly due to an abnormal T-wave axis. Inverted T-waves in the right precordial leads (V₁–V₃) or beyond were present in 0.5% of the population. No increase in mortality or SCD was associated with right precordial T-wave inversions. In, Tiivistelmä Sydänperäinen äkkikuolema on yleisin kuolinsyy länsimaissa, missä puolet sydänkuolemista ja 15–20 % kokonaiskuolleisuudesta johtuu äkillisestä sydänpysähdyksestä. Sepelvaltimotauti on yleisin taustalla oleva syy, ja jopa puolessa sepelvaltimotautikuolemista äkkikuolema on taudin ensimmäinen oire. Jo pitkään on yritetty kehittää menetelmiä, joilla voitaisiin tunnistaa suurimmassa äkkikuoleman vaarassa olevat. 12-kanavainen EKG on laajalti käytössä oleva tutkimus, jolla tutkitaan sydämen sähköistä toimintaa, mutta sydänperäistä äkkikuolemaa spesifisti väestössä ennustavia EKG-poikkeavuuksia ei ole juuri pystytty osoittamaan. Tämän väitöskirjatyön tarkoituksena oli tutkia, miten EKG:ssä nähtävät ilmiöt kuten QRS kompleksin kesto, QRS-kompleksin ja T-aallon välinen kulma, kääntyneet T-aallot sekä PR-aika korreloivat ennusteeseen väestötasolla. Tutkimme 10899 suomalaisen keski-ikäisen henkilön (52 % miehiä) EKG:t, jotka oli rekisteröity 1966–1972, ja seurasimme tutkittavia keskimäärin 30 (± 11) vuotta. Leventynyt QRS kompleksi ≥ 110 ms löytyi 1.3 %:lta ja epäspesifi kammionsisäinen johtumishäiriö eli IVCD (QRS ≥ 110 ms ilman osittaista tai täydellistä haarakatkosta) 0.6 %:lta tutkituista. Molemmat muutokset liittyivät lisääntyneeseen kokonaiskuolleisuuteen sekä sydänkuoleman riskiin. QRS kompleksin kesto ≥ 110 ms assosioitui lisäksi kaksinkertaiseen ja IVCD kolminkertaiseen äkkikuolemariskiin. 2 %:lla tutkituista sydänlihaksen depolarisaation suuntaa kuvaavan QRS-kompleksin akselin ja repolarisaatiota kuvaavan T-aallon akselin välinen frontaalitason QRS-T kulma oli leveä ≥ 100°. Näillä henkilöillä kokonaiskuolleisuus oli lisääntynyt, ja sydänperäisen äkkikuoleman riski oli yli kaksinkertainen verrattuna henkilöihin jolla QRS-T kulma oli < 100°. Oikeanpuoleisissa rintakytkennöissä V₁–V₃ todettiin negatiiviset T-aallot 0.5 %:lla tutkituista, mutta näillä ei ollut vaikutusta kuolleisuuteen. Se

The ventricle exhibits gradients in repolarization time in both transmural and apicobasal directions. These gradients, caused by the varying strengths of cellular ionic currents in the different regions, affect the morphology of the electrocardiographic T wave. Abnormal gradients, observed clinically by alterations in the ECG, can increase susceptibility to arrhythmias, and therefore the characteristics of both gradients as well as their roles in manifesting the T wave must be understood. The UCLA rabbit ventricular action potential model is based on experimental data from rabbit ventricular myocytes along with reported ion channel properties. To recreate the repolarization gradients in the ventricle, alterations were made to the conduction of repolarizing currents, IKr and Ito,f in the single cell model to simulate the different APDs observed in-situ. The resulting cells were then incorporated into a 3D ventricle model. Simulations were performed with varying presence and direction of repolarization gradients, and an in-silico ECG was calculated. It was found that transmurally, APD epi must be shorter than APD endo and apicobasally, APD base must be shorter than APD apex to give a correct ECG.

The ventricle exhibits gradients in repolarization time in both transmural and apicobasal directions. These gradients, caused by the varying strengths of cellular ionic currents in the different regions, affect the morphology of the electrocardiographic T wave. Abnormal gradients, observed clinically by alterations in the ECG, can increase susceptibility to arrhythmias, and therefore the characteristics of both gradients as well as their roles in manifesting the T wave must be understood. The UCLA rabbit ventricular action potential model is based on experimental data from rabbit ventricular myocytes along with reported ion channel properties. To recreate the repolarization gradients in the ventricle, alterations were made to the conduction of repolarizing currents, IKr and Ito,f in the single cell model to simulate the different APDs observed in-situ. The resulting cells were then incorporated into a 3D ventricle model. Simulations were performed with varying presence and direction of repolarization gradients, and an in-silico ECG was calculated. It was found that transmurally, APD epi must be shorter than APD endo and apicobasally, APD base must be shorter than APD apex to give a correct ECG.

We present two patients in whom negative T waves are developed, and appeared in the electrocar diogram as a result of the electric cardiac memory. Though described many years ago, this phenomenon is the cause for T-wave misinterpretation due to cardiac ischemia. It can be seen in certain clinical situations which lead to suspect its presence., Presentamos dos pacientes en los que se desarro-llaron ondas T negativas que aparecen en el electro-cardiograma por la memoria eléctrica cardíaca. Este fenómeno aunque fue descrito hace muchos años es causa de interpretación errónea de ondas T debido a isquemia cardíaca, y puede ser visto en ciertas situa- ciones clínicas que permiten sospechar su presencia.

We present two patients in whom negative T waves are developed, and appeared in the electrocar diogram as a result of the electric cardiac memory. Though described many years ago, this phenomenon is the cause for T-wave misinterpretation due to cardiac ischemia. It can be seen in certain clinical situations which lead to suspect its presence., Presentamos dos pacientes en los que se desarro-llaron ondas T negativas que aparecen en el electro-cardiograma por la memoria eléctrica cardíaca. Este fenómeno aunque fue descrito hace muchos años es causa de interpretación errónea de ondas T debido a isquemia cardíaca, y puede ser visto en ciertas situa- ciones clínicas que permiten sospechar su presencia.

BACKGROUND: Several conditions with repolarization disturbances are associated with increased level of nondipolar components of the T wave. The nondipolar content has been proposed as a measure of repolarization inhomogeneity. This computer simulation study examines the link between increased nondipolar components and increased repolarization inhomogeneity in an established model. METHODS: The simulation was performed with Ecgsim software that uses the equivalent double-layer source model. In the model, the shape of transmembrane potential is derived from biological recordings. Increased repolarization inhomogeneity was simulated globally by increasing the variance in action potential duration and locally by introducing changes mimicking acute myocardial infarction. We synthesized surface ECG recordings with 12, 18, and 300 leads. The T-wave residue was calculated by singular value decomposition. The study examined the effects of the number of ECG leads, changes in definition of end of T wave and random noise added to the signal. RESULTS: Normal myocardial source gave a low level of nondipolar content. Increased nondipolar content was observed in the two types of increased repolarization inhomogeneity. Noise gave a large increase in the nondipolar content. The sensitivity of the result to noise increased when a higher number of principal components were used in the computation. CONCLUSIONS: The nondipolar content of the T wave was associated with repolarization inhomogeneity in the computer model. The measure was very sensitive to noise, especially when principal components of high order were included in the computations. Increased number of ECG leads resulted in an increased signal-to-noise ratio.

The purposes are to validate the noninvasive parameters, QT interval, QT dispersion, Tpeak-Tend interval, and the activation recovery time (ART) for estimation of global dispersion of ventricular repolarization (DVR), and to investigate the changes of repolarization sequence and DVR by altered ventricular pacing sites. The material consisted of 12 patients (Study I) and two series healthy pigs with 10 in each (Studies II and III; Studies IV and V). In Study I, endocardial MAPs and unipolar electrograms were recorded using the CARTO system in 12 patients. End of repolarization (EOR) times from the MAPs and ARTs from the unipolar electrograms were acquired and 3-dimensional maps of global EOR and ART were reconstructed. The ART sequence was consistent with that of EOR and no significant diffence was found between EOR times and ART. A significant, positive correlation between the ART and the EOR time was also found in all maps. These findings suggest the usefulness of the ART in evaluation of global sequence and dispersion of ventricular repolarization. In Studies II and III, MAP mapping was performed over both the ventricular endo- and the epicardium using the CARTO system in 10 open-chest pigs, from which the EOR times over the epi- (EORepi), endocardium (EORendo) and over both (EORtotal) were obtained- 12-lead ECG were recorded simultaneously. The QTpeak intervals were significantly smaller than the maximal EORepi. No significant difference was found between the maximal QTend interval and the maximal EORendo, between the maximal QTend interval and the maximal EORtotal nor between the minimal QTpeak interval and the minimal EORtotal, which suggests that not only the transmural gradients, but also the apico-basal repolarization gradients contribute to the genesis of the T wave. In addition, the maximal Tpeak-Tend intervals were consistent with the dispersion of EOR-total, and significantly correlated with the dispersion of EOR-total. However, the mean Tpeak-Tend inter

Práce se zabývá intraaortální balonkovou kontrapulzací, která slouží jako podpůrná metoda pro činnost selhávajícího srdce. V první části práce je popsán princip metody, její efekt a základní indikace a kontraindikace jejího použití. V druhé části práce je navržená metoda zrealizována v grafickém prostředí LabVIEW. Výstupem programu jsou detekované konce T vln pro inflaci balonku a R vlny pro jeho deflaci., The thesis is concerned with intraaortic balloon counterpulsation, which serves as a supporting method for the operation of failing heart. In the teoretical part is described principle of this method, its effects and the basic indications and contraindications of using. In the practical part of this work is proposed method for detecting triggering points realized in graphical program LabVIEW. The program outputs are detected ends of T wave for balloon inflation and R wave for its deflation.

Automatická detekce charakteristických vln v EKG signálu a jejich rozměření je základní procedurou jakékoliv počítačové analýzy EKG. Zároveň je nezbytným krokem k usnadnění práce lékařům při vyhodnocování dlouhých záznamů. V této práci byla navržena a vyhodnocena metoda detekce a rozměřování jednosvodového záznamu EKG využívající dyadickou vlnkovou transformaci s následnou korekcí v pseudoortogonálním svodovém systému vybraného ze standardního 12-ti svodového systému. Metoda využívá informace o pozici páru pozitivní maximum – negativní minimum k detekci charakteristických vln. Nejprve je detekován QRS komplex a jeho morfologie, tedy přítomnost vlny Q a S, následně jsou stanoveny začátek a konec QRS komplexu. Poté je v definovaném vyhledávacím okně detekována a rozměřena vlna T a nakonec je detekována a rozměřena vlna P. Při použití této metody byly porovnány výsledky pro dva typy vlnek, haarovu a quadratic spline. Navržená metoda byla otestována na databázi CSE. Při použití haarovy vlnky byla senzitivita QRS komplexu 99,14%. V práci byla následně otestována i přesnost rozměřování P-vlny, komplexu QRS a T-vlny. Při rozměřování P-vlny a komplexu QRS bylo dosaženo poměrně dobrých výsledků. Při detekci konce T-vlny byly výsledky horší. Odchylky jsou v práci přehledně zobrazeny v histogramech., Automatic detection and delineation of ECG characteristic points is a basic procedure of any analyze of ECG using computer. This detection is a necessary step to simplify the work of cardiologists to evaluate long ECG records. In this thesis is proposed and evaluate a method of detection and delineation in a single-lead ECG using dyadic wavelet transform followed by correction in pseudo-orthogonal lead system taken from standard 12-lead system. The method uses information about position of positive maximum – negative minimum pair to detect ECG characteristic waves. At first the QRS complex is detected and than its morphology (waves Q and S) and the onset and end of the complex. After that the T-wave is detected and delineated within a searching window dependent on QRS position. And last the P-wave is detected and delineated. There are used two types of wavelets in developed method, “haar” and “quadratic spline”. The developed method was evaluated on CSE database. When haar wavelet was used the QRS detector sensitivity was 99.14%. In the work is also evaluated the accuracy of delineation characteristic points. As the P-wave and QRS complex delineation produced quite good results the T-wave end delineator produced relatively big deviations. All deviations are presented in histograms.

Práce se zabývá intraaortální balonkovou kontrapulzací, která slouží jako podpůrná metoda pro činnost selhávajícího srdce. V první části práce je popsán princip metody, její efekt a základní indikace a kontraindikace jejího použití. V druhé části práce je navržená metoda zrealizována v grafickém prostředí LabVIEW. Výstupem programu jsou detekované konce T vln pro inflaci balonku a R vlny pro jeho deflaci., The thesis is concerned with intraaortic balloon counterpulsation, which serves as a supporting method for the operation of failing heart. In the teoretical part is described principle of this method, its effects and the basic indications and contraindications of using. In the practical part of this work is proposed method for detecting triggering points realized in graphical program LabVIEW. The program outputs are detected ends of T wave for balloon inflation and R wave for its deflation.

V rámci diplomové práce autor navrhl a realizoval detektor vrcholu a konce T vlny za pomocí dosud nepublikované transformace svodů na bázi lineární regrese napříč svody. Během vývoje se daná transformace ukázala jako užitečný nástroj pro detekci QRS komplexu. Realizovaný QRS detektor byl testován na databázi CSE a výsledky byly porovnány výsledky jiných autorů. Detektor parametrů T vlny byl testován kvalitativně a výsledky byly uvedeny ve formě grafických ukázek., A T wave peak and offset detector based on an unpublished lead transformation that can be briefly described as multilead linear regression was proposed and implemented afterwards. Potential of the transformation as a useful QRS detection tool was revealed later on. Proposed QRS detector was put to the test of CSE database. Results were compared with work of other authors. Results of T wave peak and offset detector were introduced in visual way.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a na závěr také s metodou detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a také s metodou a realizací detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a také s metodou a realizací detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.

V rámci diplomové práce autor navrhl a realizoval detektor vrcholu a konce T vlny za pomocí dosud nepublikované transformace svodů na bázi lineární regrese napříč svody. Během vývoje se daná transformace ukázala jako užitečný nástroj pro detekci QRS komplexu. Realizovaný QRS detektor byl testován na databázi CSE a výsledky byly porovnány výsledky jiných autorů. Detektor parametrů T vlny byl testován kvalitativně a výsledky byly uvedeny ve formě grafických ukázek., A T wave peak and offset detector based on an unpublished lead transformation that can be briefly described as multilead linear regression was proposed and implemented afterwards. Potential of the transformation as a useful QRS detection tool was revealed later on. Proposed QRS detector was put to the test of CSE database. Results were compared with work of other authors. Results of T wave peak and offset detector were introduced in visual way.

Automatická detekce charakteristických vln v EKG signálu a jejich rozměření je základní procedurou jakékoliv počítačové analýzy EKG. Zároveň je nezbytným krokem k usnadnění práce lékařům při vyhodnocování dlouhých záznamů. V této práci byla navržena a vyhodnocena metoda detekce a rozměřování jednosvodového záznamu EKG využívající dyadickou vlnkovou transformaci s následnou korekcí v pseudoortogonálním svodovém systému vybraného ze standardního 12-ti svodového systému. Metoda využívá informace o pozici páru pozitivní maximum – negativní minimum k detekci charakteristických vln. Nejprve je detekován QRS komplex a jeho morfologie, tedy přítomnost vlny Q a S, následně jsou stanoveny začátek a konec QRS komplexu. Poté je v definovaném vyhledávacím okně detekována a rozměřena vlna T a nakonec je detekována a rozměřena vlna P. Při použití této metody byly porovnány výsledky pro dva typy vlnek, haarovu a quadratic spline. Navržená metoda byla otestována na databázi CSE. Při použití haarovy vlnky byla senzitivita QRS komplexu 99,14%. V práci byla následně otestována i přesnost rozměřování P-vlny, komplexu QRS a T-vlny. Při rozměřování P-vlny a komplexu QRS bylo dosaženo poměrně dobrých výsledků. Při detekci konce T-vlny byly výsledky horší. Odchylky jsou v práci přehledně zobrazeny v histogramech., Automatic detection and delineation of ECG characteristic points is a basic procedure of any analyze of ECG using computer. This detection is a necessary step to simplify the work of cardiologists to evaluate long ECG records. In this thesis is proposed and evaluate a method of detection and delineation in a single-lead ECG using dyadic wavelet transform followed by correction in pseudo-orthogonal lead system taken from standard 12-lead system. The method uses information about position of positive maximum – negative minimum pair to detect ECG characteristic waves. At first the QRS complex is detected and than its morphology (waves Q and S) and the onset and end of the complex. After that the T-wave is detected and delineated within a searching window dependent on QRS position. And last the P-wave is detected and delineated. There are used two types of wavelets in developed method, “haar” and “quadratic spline”. The developed method was evaluated on CSE database. When haar wavelet was used the QRS detector sensitivity was 99.14%. In the work is also evaluated the accuracy of delineation characteristic points. As the P-wave and QRS complex delineation produced quite good results the T-wave end delineator produced relatively big deviations. All deviations are presented in histograms.

V rámci diplomové práce autor navrhl a realizoval detektor vrcholu a konce T vlny za pomocí dosud nepublikované transformace svodů na bázi lineární regrese napříč svody. Během vývoje se daná transformace ukázala jako užitečný nástroj pro detekci QRS komplexu. Realizovaný QRS detektor byl testován na databázi CSE a výsledky byly porovnány výsledky jiných autorů. Detektor parametrů T vlny byl testován kvalitativně a výsledky byly uvedeny ve formě grafických ukázek., A T wave peak and offset detector based on an unpublished lead transformation that can be briefly described as multilead linear regression was proposed and implemented afterwards. Potential of the transformation as a useful QRS detection tool was revealed later on. Proposed QRS detector was put to the test of CSE database. Results were compared with work of other authors. Results of T wave peak and offset detector were introduced in visual way.

Práce se zabývá intraaortální balonkovou kontrapulzací, která slouží jako podpůrná metoda pro činnost selhávajícího srdce. V první části práce je popsán princip metody, její efekt a základní indikace a kontraindikace jejího použití. V druhé části práce je navržená metoda zrealizována v grafickém prostředí LabVIEW. Výstupem programu jsou detekované konce T vln pro inflaci balonku a R vlny pro jeho deflaci., The thesis is concerned with intraaortic balloon counterpulsation, which serves as a supporting method for the operation of failing heart. In the teoretical part is described principle of this method, its effects and the basic indications and contraindications of using. In the practical part of this work is proposed method for detecting triggering points realized in graphical program LabVIEW. The program outputs are detected ends of T wave for balloon inflation and R wave for its deflation.

Práce se zabývá intraaortální balonkovou kontrapulzací, která slouží jako podpůrná metoda pro činnost selhávajícího srdce. V první části práce je popsán princip metody, její efekt a základní indikace a kontraindikace jejího použití. V druhé části práce je navržená metoda zrealizována v grafickém prostředí LabVIEW. Výstupem programu jsou detekované konce T vln pro inflaci balonku a R vlny pro jeho deflaci., The thesis is concerned with intraaortic balloon counterpulsation, which serves as a supporting method for the operation of failing heart. In the teoretical part is described principle of this method, its effects and the basic indications and contraindications of using. In the practical part of this work is proposed method for detecting triggering points realized in graphical program LabVIEW. The program outputs are detected ends of T wave for balloon inflation and R wave for its deflation.

Automatická detekce charakteristických vln v EKG signálu a jejich rozměření je základní procedurou jakékoliv počítačové analýzy EKG. Zároveň je nezbytným krokem k usnadnění práce lékařům při vyhodnocování dlouhých záznamů. V této práci byla navržena a vyhodnocena metoda detekce a rozměřování jednosvodového záznamu EKG využívající dyadickou vlnkovou transformaci s následnou korekcí v pseudoortogonálním svodovém systému vybraného ze standardního 12-ti svodového systému. Metoda využívá informace o pozici páru pozitivní maximum – negativní minimum k detekci charakteristických vln. Nejprve je detekován QRS komplex a jeho morfologie, tedy přítomnost vlny Q a S, následně jsou stanoveny začátek a konec QRS komplexu. Poté je v definovaném vyhledávacím okně detekována a rozměřena vlna T a nakonec je detekována a rozměřena vlna P. Při použití této metody byly porovnány výsledky pro dva typy vlnek, haarovu a quadratic spline. Navržená metoda byla otestována na databázi CSE. Při použití haarovy vlnky byla senzitivita QRS komplexu 99,14%. V práci byla následně otestována i přesnost rozměřování P-vlny, komplexu QRS a T-vlny. Při rozměřování P-vlny a komplexu QRS bylo dosaženo poměrně dobrých výsledků. Při detekci konce T-vlny byly výsledky horší. Odchylky jsou v práci přehledně zobrazeny v histogramech., Automatic detection and delineation of ECG characteristic points is a basic procedure of any analyze of ECG using computer. This detection is a necessary step to simplify the work of cardiologists to evaluate long ECG records. In this thesis is proposed and evaluate a method of detection and delineation in a single-lead ECG using dyadic wavelet transform followed by correction in pseudo-orthogonal lead system taken from standard 12-lead system. The method uses information about position of positive maximum – negative minimum pair to detect ECG characteristic waves. At first the QRS complex is detected and than its morphology (waves Q and S) and the onset and end of the complex. After that the T-wave is detected and delineated within a searching window dependent on QRS position. And last the P-wave is detected and delineated. There are used two types of wavelets in developed method, “haar” and “quadratic spline”. The developed method was evaluated on CSE database. When haar wavelet was used the QRS detector sensitivity was 99.14%. In the work is also evaluated the accuracy of delineation characteristic points. As the P-wave and QRS complex delineation produced quite good results the T-wave end delineator produced relatively big deviations. All deviations are presented in histograms.

Automatická detekce charakteristických vln v EKG signálu a jejich rozměření je základní procedurou jakékoliv počítačové analýzy EKG. Zároveň je nezbytným krokem k usnadnění práce lékařům při vyhodnocování dlouhých záznamů. V této práci byla navržena a vyhodnocena metoda detekce a rozměřování jednosvodového záznamu EKG využívající dyadickou vlnkovou transformaci s následnou korekcí v pseudoortogonálním svodovém systému vybraného ze standardního 12-ti svodového systému. Metoda využívá informace o pozici páru pozitivní maximum – negativní minimum k detekci charakteristických vln. Nejprve je detekován QRS komplex a jeho morfologie, tedy přítomnost vlny Q a S, následně jsou stanoveny začátek a konec QRS komplexu. Poté je v definovaném vyhledávacím okně detekována a rozměřena vlna T a nakonec je detekována a rozměřena vlna P. Při použití této metody byly porovnány výsledky pro dva typy vlnek, haarovu a quadratic spline. Navržená metoda byla otestována na databázi CSE. Při použití haarovy vlnky byla senzitivita QRS komplexu 99,14%. V práci byla následně otestována i přesnost rozměřování P-vlny, komplexu QRS a T-vlny. Při rozměřování P-vlny a komplexu QRS bylo dosaženo poměrně dobrých výsledků. Při detekci konce T-vlny byly výsledky horší. Odchylky jsou v práci přehledně zobrazeny v histogramech., Automatic detection and delineation of ECG characteristic points is a basic procedure of any analyze of ECG using computer. This detection is a necessary step to simplify the work of cardiologists to evaluate long ECG records. In this thesis is proposed and evaluate a method of detection and delineation in a single-lead ECG using dyadic wavelet transform followed by correction in pseudo-orthogonal lead system taken from standard 12-lead system. The method uses information about position of positive maximum – negative minimum pair to detect ECG characteristic waves. At first the QRS complex is detected and than its morphology (waves Q and S) and the onset and end of the complex. After that the T-wave is detected and delineated within a searching window dependent on QRS position. And last the P-wave is detected and delineated. There are used two types of wavelets in developed method, “haar” and “quadratic spline”. The developed method was evaluated on CSE database. When haar wavelet was used the QRS detector sensitivity was 99.14%. In the work is also evaluated the accuracy of delineation characteristic points. As the P-wave and QRS complex delineation produced quite good results the T-wave end delineator produced relatively big deviations. All deviations are presented in histograms.

Táto bakalárska práca je zameraná na meranie a detekciu QT intervalu. Práca začína problematikou rozmerania EKG signálu so zameraním na metódy detekcie QT intervalu pomocou prvej a druhej derivácie. Následne je popísaný detektor QRS komplexu. Pre uvedenú detekciu je vhodný detektor založený na algoritme Pan - Tompkins. Ďalej je v praktickej časti je popísaný algoritmus pre detekciu QT intervalu s využitím prvej a druhej derivácie. Tento algoritmus bol otestovaný na štandardnej databáze CSE. Detekované pozície boli porovnané s referenčnými hodnotami a dosiahnuté výsledky zhodnotené v závere., This bachelor´s thesis deals with QT interval measurement and detection. The thesis starts with problematic of ECG signal delineation and its methods of detection of QT interval using first and second derivate. Next part of the work describes QRS complex detector. For this detection it is suitable to use detector based on the Pan-Tompkins algorithm. Next in practical part of the work is described algorithm of the detection of QT interval using first and second derivate. Selected algotithm was evaluated on the standard CSE database. Detected positions were compared with reference values. Result of this work is evaluation of results.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a také s metodou a realizací detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.

Táto bakalárska práca je zameraná na meranie a detekciu QT intervalu. Práca začína problematikou rozmerania EKG signálu so zameraním na metódy detekcie QT intervalu pomocou prvej a druhej derivácie. Následne je popísaný detektor QRS komplexu. Pre uvedenú detekciu je vhodný detektor založený na algoritme Pan - Tompkins. Ďalej je v praktickej časti je popísaný algoritmus pre detekciu QT intervalu s využitím prvej a druhej derivácie. Tento algoritmus bol otestovaný na štandardnej databáze CSE. Detekované pozície boli porovnané s referenčnými hodnotami a dosiahnuté výsledky zhodnotené v závere., This bachelor´s thesis deals with QT interval measurement and detection. The thesis starts with problematic of ECG signal delineation and its methods of detection of QT interval using first and second derivate. Next part of the work describes QRS complex detector. For this detection it is suitable to use detector based on the Pan-Tompkins algorithm. Next in practical part of the work is described algorithm of the detection of QT interval using first and second derivate. Selected algotithm was evaluated on the standard CSE database. Detected positions were compared with reference values. Result of this work is evaluation of results.

V rámci diplomové práce autor navrhl a realizoval detektor vrcholu a konce T vlny za pomocí dosud nepublikované transformace svodů na bázi lineární regrese napříč svody. Během vývoje se daná transformace ukázala jako užitečný nástroj pro detekci QRS komplexu. Realizovaný QRS detektor byl testován na databázi CSE a výsledky byly porovnány výsledky jiných autorů. Detektor parametrů T vlny byl testován kvalitativně a výsledky byly uvedeny ve formě grafických ukázek., A T wave peak and offset detector based on an unpublished lead transformation that can be briefly described as multilead linear regression was proposed and implemented afterwards. Potential of the transformation as a useful QRS detection tool was revealed later on. Proposed QRS detector was put to the test of CSE database. Results were compared with work of other authors. Results of T wave peak and offset detector were introduced in visual way.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a na závěr také s metodou detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a také s metodou a realizací detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.

V rámci diplomové práce autor navrhl a realizoval detektor vrcholu a konce T vlny za pomocí dosud nepublikované transformace svodů na bázi lineární regrese napříč svody. Během vývoje se daná transformace ukázala jako užitečný nástroj pro detekci QRS komplexu. Realizovaný QRS detektor byl testován na databázi CSE a výsledky byly porovnány výsledky jiných autorů. Detektor parametrů T vlny byl testován kvalitativně a výsledky byly uvedeny ve formě grafických ukázek., A T wave peak and offset detector based on an unpublished lead transformation that can be briefly described as multilead linear regression was proposed and implemented afterwards. Potential of the transformation as a useful QRS detection tool was revealed later on. Proposed QRS detector was put to the test of CSE database. Results were compared with work of other authors. Results of T wave peak and offset detector were introduced in visual way.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a na závěr také s metodou detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.

Práce se zabývá intraaortální balonkovou kontrapulzací, která slouží jako podpůrná metoda pro činnost selhávajícího srdce. V první části práce je popsán princip metody, její efekt a základní indikace a kontraindikace jejího použití. V druhé části práce je navržená metoda zrealizována v grafickém prostředí LabVIEW. Výstupem programu jsou detekované konce T vln pro inflaci balonku a R vlny pro jeho deflaci., The thesis is concerned with intraaortic balloon counterpulsation, which serves as a supporting method for the operation of failing heart. In the teoretical part is described principle of this method, its effects and the basic indications and contraindications of using. In the practical part of this work is proposed method for detecting triggering points realized in graphical program LabVIEW. The program outputs are detected ends of T wave for balloon inflation and R wave for its deflation.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a na závěr také s metodou detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.

Práce se zabývá intraaortální balonkovou kontrapulzací, která slouží jako podpůrná metoda pro činnost selhávajícího srdce. V první části práce je popsán princip metody, její efekt a základní indikace a kontraindikace jejího použití. V druhé části práce je navržená metoda zrealizována v grafickém prostředí LabVIEW. Výstupem programu jsou detekované konce T vln pro inflaci balonku a R vlny pro jeho deflaci., The thesis is concerned with intraaortic balloon counterpulsation, which serves as a supporting method for the operation of failing heart. In the teoretical part is described principle of this method, its effects and the basic indications and contraindications of using. In the practical part of this work is proposed method for detecting triggering points realized in graphical program LabVIEW. The program outputs are detected ends of T wave for balloon inflation and R wave for its deflation.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a také s metodou a realizací detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.

Tato práce se zabývá optimální detekcí konce vlny T v EKG signálech, která využívá metodu vlnkové transformace. Metoda vlnkové transformace je dnes poměrně dost užívaná, protože v praxi dosahuje dobrých výsledků. Cílem práce je obecné seznámení s EKG signálem, vlnkovou transformací a na závěr také s metodou detekce konce T vlny., This work deals with the optimal detection of the T wave end in ECG signals, which uses the method of wavelet transform. Method of wavelet transform is now used quite a lot, because in practice it achieves good results. The aim of this work is a general introduction to ECG signal, wavelet transforms, and also with the method and realization of the T wave end detection.