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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

A prospective observational study to investigate the effect of prehospital airway management strategies on mortality and morbidity of patients who experience return of spontaneous circulation post cardiac arrest and are transferred directly to regional Heart Attack Centres by the Ambulance Service

Edwards, Timothy Robin January 2017 (has links)
Introduction: The most appropriate airway management technique for use by paramedics in out-of-hospital cardiac arrest is yet to be determined and evidence relating to the influence of airway management strategy on outcome remains equivocal. In cases where return of spontaneous circulation (ROSC) occurs following out-of-hospital cardiac arrest, patients may undergo direct transfer to a specialist heart attack centre (HAC) where the post resuscitation 12 lead ECG demonstrates evidence of ST elevation myocardial infarction. To date, no studies have investigated the role of airway management strategy on outcomes in this sub-set of patients. The AMICABLE (Airway Management In Cardiac Arrest, Basic, Laryngeal mask airway, Endotracheal intubation) study therefore sought to investigate the influence of prehospital airway management strategy on outcomes in patients transferred by the ambulance service directly to a HAC post ROSC. Methods: Adults with ROSC post out-of-hospital cardiac arrest who met local criteria for transfer to a HAC were identified prospectively. Ambulance records were reviewed to determine prehospital airway management approach and collect physiological and demographic data. HAC notes were obtained to determine in-hospital course and quantify neurological outcome via the Cerebral Performance Category (CPC) scale. Neurologically intact survivors were contacted post discharge to assess quality of life via the SF-36 health survey. Statistical analyses were performed via Chi-square, Mann Whitney U test, odds ratios, and binomial logistic regression. Results: A total of 220 patients were recruited between August 2013 and August 2014, with complete outcome data available for 209. The age of patients ranged from 22-96 years and 71.3% were male (n=149). Airway management was undertaken using a supraglottic airway (SGA) in 72.7% of cases (n=152) with the remainder undergoing endotracheal intubation (ETI). There was no significant difference in the proportion of patients with good neurological outcome (CPC 1&2) between the SGA and ETI groups (p=.286). Similarly, binomial logistic regression incorporating factors known to influence outcome demonstrated no significant difference between the SGA and ETI groups (Adjusted OR 0.725, 95% CI 0.337-1.561). Clinical and demographic variables associated with good neurological outcome included the presence of a shockable rhythm (p < .001), exposure to angiography (p < .001), younger age (p < .001) and shorter time to ROSC (p < .001). Due to an inadequate response rate (25.4%, n=15) analysis of SF36 data was limited to descriptive statistics. Limitations: The study only included patients who achieved ROSC and met the criteria for direct transfer to a HAC. Results are therefore not generalisable to more heterogenous resuscitation populations. Accuracy of clinical decision making and ECG interpretation were not assessed and therefore some patients included in the study may have been inappropriately transferred to a HAC. The low SF-36 survey response rate limited the level of neurological outcome analysis that could be undertaken. Conclusion: In this study, there was no significant difference in the proportion of good neurological outcomes in patients managed with SGA versus ETI during cardiac arrest. Further research incorporating randomised controlled trials is required to provide more definitive evidence in relation to the optimal airway management strategy in out-of-hospital cardiac arrest.
102

Liberação de biomarcadores de necrose miocárdica após angioplastia coronária percutânea em ausência de infarto do miocárdio manifesto: estudo com ressonância nuclear magnética / Biomarker release after percutaneous coronary intervention in patients without definitive myocardial infarction assessed by cardiac magnetic resonance with late gadolinium enhancemen

Melo, Rodrigo Morel Vieira de 25 February 2016 (has links)
Introdução: A liberação de biomarcadores de necrose miocárdica após a intervenção coronária percutânea (ICP) ocorre frequentemente. No entanto, a correlação entre a liberação dos biomarcadores e o diagnóstico do infarto agudo do miocárdio (IAM) tipo 4a tem gerado controvérsia, especialmente com o aumento da sensibilidade nos ensaios de troponina (Tn). Neste estudo, objetivamos quantificar a liberação dos biomarcadores cardíacos em pacientes submetidos à ICP eletiva sem o surgimento de novo realce tardio pelo gadolínio (RTG) na ressonância magnética cardíaca (RMC) após o procedimento. Métodos: Foram incluídos pacientes consecutivos com doença arterial coronária estável e função ventricular preservada, com indicação eletiva para ICP em pelo menos duas artérias epicárdicas. RMC com RTG foi realizada em todos os pacientes antes e depois das intervenções. Medidas seriadas de Tn e creatinoquinase fração MB (CK-MB) foram realizadas imediatamente antes do procedimento até 48 horas após. Pacientes com novo RTG na RMC após o procedimento foram excluídos. Resultados: 71 pacientes foram referenciados para a realização eletiva da ICP sendo que 15 (21,1%) foram excluídos, 10 (14,1%) por causa do surgimento de um novo RTG na RMC após a ICP. Nos 56 pacientes sem a evidência de IAM tipo 4a pela RMC predominava o gênero masculino 37 (66,1%) com idade média de 61,7 (± 8,4) anos e escore de SYNTAX médio de 16,6 (± 7,7). Após a ICP, 48 (85,1%) pacientes apresentaram um pico de elevação de Tn acima do percentil 99 sendo que em 32 (57,1%) a elevação foi superior a 5 vezes esse limite, enquanto que apenas 2 (3,6%) apresentaram um pico de CK-MB maior do que 5 vezes o percentil 99. A mediana do pico de liberação da Tn foi de 0,290 (0,061 - 1,09) ng/mL, valor 7,25 vezes superior ao percentil 99. Conclusão: Diferentemente da CK-MB, a liberação da troponina I ocorre com frequência após procedimento de ICP mesmo na ausência de realce tardio pelo gadolínio na ressonância magnética cardíaca / Background: The release of myocardial necrosis biomarkers after percutaneous coronary intervention (PCI) frequently occurs. However, the correlation between biomarker release and the diagnosis of procedurerelated myocardial infarction (MI) (type 4a) has been controversial. This study aims to evaluate the amount and pattern of cardiac biomarker release after elective PCI in patients without the image of a new MI after the procedure assessed by cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE). Methods: Patients with normal baseline cardiac biomarkers referred for elective PCI were prospectively included. CMR with LGE was performed in all of the patients before and after the interventions. Measurements of troponin I (TnI) and creatinekinase MB fraction (CK-MB) were systematically performed before and after the procedure. Patients with a new LGE on the post-procedure CMR were excluded. Results: Of the 56 patients without the evidence of a procedure-related MI assessed by the CMR after PCI, 48 (85.1%) exhibited a TnI elevation peak above the 99th percentile. In 32 (57.1%), the peak was greater than 5 times this limit. On the other hand, 17 (30.4%) had a CK-MB peak above the limit of the 99th percentile, and this peak was greater than 5 times the 99th percentile in only 2 patients (3.6%). The median peak release of TnI was 0.290 (0.061 to 1.09) ng/ml, which is 7.25-fold higher than the 99th percentile. Conclusions: In contrast to CK-MB, TnI release often occurs after an elective PCI procedure, despite the absence of a new LGE on CMR
103

Perkutane koronare Intervention bei Stenosen und Verschlüssen in aortokoronaren Venenbypässen - Wertigkeit der zusätzlichen lokalen Thrombolyse im Vergleich zur alleinigen Ballondilatation mit Stent / Percutaneous coronary intervention in patients with stenosis or occlusion in coronary artery bypass grafts use of additive intracoronary thrombolysis compared with conventional percutaneous coronary intervention alone

Drewek-Platena, Sylwia Izabella 01 February 2011 (has links)
No description available.
104

Etude de l'angioplastie guidée par tomographie en cohérence optique / Optical coherence tomography-guided angioplasty as a new tool to improve coronary evaluation and guide percutaneous coronary intervention procedures

Huang, Jianfeng 15 June 2018 (has links)
L'imagerie par tomographie en cohérence optique (OCT) est prometteuse comme support de la prise de décision au cours des procédures d'interventions coronariennes percutanées (PCI), pou évaluer les lésions athéromateuses, juger de la bonne implantation du stent, et dépister les lésions vasculaires dues au stent. L'OCT représente donc bien une aide potentielle pour le cardiologue interventionnel tout au long de la procédure de stenting, avec un impact certain sur la stratégie interventionnelle initialement programmée. De plus, l'OCT se révèle comme un nouvel outil pour prédire la dissection des bords de stent chez les patient avec ACS sans élévation du segment ST, rendant possible une stratification des patients quant à ce risque. Des essais cliniques randomisés sont maintenant nécessaires pour savoir si l'assistance par l'OCT pendant la procédure améliore le pronostic à long terme des patients après PCI / Optical Coherence Tomography (OCT) imaging is promising in decision making during Percutaneus Coronary Interventions {PCI) procedures, including evaluating controversial plaque lesions, assessing stent implantation, and surveying stent-related vascular injury. Thus, OCT has potential to guide interventional cardiologists throughout the stent implantation procedure, impacting on planned interventional strategy. In addition, OCT is the most novel image technology to predict stent edge dissection for patients with non-ST-segment elevation ACS, enabling risk stratification of patients who are at a higher risk of this complication. Large-scale randomized trials are now warranted to assess whether OCT results and guidance during de procedure improve long-term clinical outcomes of PCis.
105

Minimizando a utilização de contraste através do uso de ultrassom intravascular durante angioplastia coronária: estudo randomizado MOZART / Intravascular ultrasound guidance to minimize the use of iodine contrast in percutaneous coronary intervention: the MOZART randomized trial

José Mariani Júnior 16 May 2018 (has links)
INTRODUÇÃO: Poucas são as estratégias testadas para reduzir o volume de contraste durante angioplastia coronária. Levantamos a hipótese de que o ultrassom intravascular teria o potencial de substituir muitas informações fornecidas pela angiografia, reduzindo, dessa forma, o volume total de contraste utilizado durante a angioplastia coronária. MÉTODOS: No total, 83 pacientes foram randomizados para realização de angioplastia guiada pela angiografia isolada ou angioplastia guiada pelo ultrassom intravascular. Ambos os grupos foram tratados com estratégias rigorosas para redução de contraste, tendo como objetivo primário o volume final de contraste utilizado na angioplastia coronária. Os pacientes foram acompanhados por um período médio de 4 meses. RESULTADOS: A mediana do volume total de contraste foi de 64,5 ml (intervalo interquartil [ITQ], 42,8-97 ml; mínimo de 19 ml e máximo de 170 ml) no grupo angioplastia guiada pela angiografia isolada vs. 20 ml (ITQ, 12,5-30 ml; mínimo de 3 ml e máximo de 54 ml) no grupo angioplastia guiada pelo ultrassom intravascular (P < 0,001). De forma semelhante, a mediana da razão entre o volume de contraste e o clearance de creatinina foi significantemente menor entre os pacientes submetidos a angioplastia guiada pelo ultrassom intravascular, quando comparados aos pacientes do grupo angioplastia guiada pela angiografia isolada (1 [ITQ, 0,6-1,9] vs. 0,4 [ITQ, 0,2- 0,5], respectivamente; P < 0,001). Os desfechos intra-hospitalares e aos 4 meses de acompanhamento não foram diferentes entre os pacientes randomizados para o grupo angioplastia guiada pela angiografia isolada e aqueles do grupo angioplastia guiada pelo ultrassom intravascular. CONCLUSÕES: A utilização racional do ultrassom intravascular como método de imagem para guiar a angioplastia foi segura e reduziu de forma significativa o volume de contraste, comparativamente à angioplastia guiada pela angiografia isolada. O uso do ultrassom intravascular para esse propósito deve ser considerado para pacientes de elevado risco para o desenvolvimento de nefropatia induzida pelo contraste ou sobrecarga de volume e que serão submetidos a angioplastia coronária / BACKGROUND: To date, few approaches have been described to reduce the final dose of contrast agent in percutaneous coronary intervention. We hypothesized that intravascular ultrasound might serve as an alternative imaging tool to angiography in many steps during percutaneous coronary intervention, thereby reducing the use of iodine contrast. METHODS: A total of 83 patients were randomized to angiography alone-guided percutaneous coronary intervention or intravascular ultrasound-guided percutaneous coronary intervention. Both groups were treated according to a pre-defined meticulous procedural strategy, and the primary endpoint was the total volume contrast agent used during percutaneous coronary intervention. Patients were followed clinically for an average of 4 months. RESULTS: The median total volume of contrast was 64.5 mL (interquartile range [IQR], 42.8 to 97 mL; minimum, 19 mL; maximum, 170 mL) in the angiography alone-guided group vs. 20 mL (IQR, 12.5 to 30 mL; minimum, 3 mL; maximum, 54 mL) in the intravascular ultrasound-guided group (P < 0.001). Similarly, the median volume of contrast/creatinine clearance ratio was significantly lower among patients treated with intravascular ultrasound-guided percutaneous coronary intervention when compared with patients treated with angiography alone-guided percutaneous coronary intervention (1 [IQR, 0.6 to 1.9] vs. 0.4 [IQR, 0.2 to 0.6], respectively; P < 0.001). In-hospital and 4-month outcomes were not different between patients randomized to angiography alone-guided and intravascular ultrasound-guided percutaneous coronary intervention. CONCLUSIONS: Thoughtful and extensive use of intravascular ultrasound as the primary imaging tool to guide percutaneous coronary intervention was safe and markedly reduced the volume of iodine contrast compared with angiographyalone guidance. The use of intravascular ultrasound should be considered for patients at high risk of contrast-induced acute kidney injury or volume overload undergoing coronary angioplasty
106

Liberação de biomarcadores de necrose miocárdica após angioplastia coronária percutânea em ausência de infarto do miocárdio manifesto: estudo com ressonância nuclear magnética / Biomarker release after percutaneous coronary intervention in patients without definitive myocardial infarction assessed by cardiac magnetic resonance with late gadolinium enhancemen

Rodrigo Morel Vieira de Melo 25 February 2016 (has links)
Introdução: A liberação de biomarcadores de necrose miocárdica após a intervenção coronária percutânea (ICP) ocorre frequentemente. No entanto, a correlação entre a liberação dos biomarcadores e o diagnóstico do infarto agudo do miocárdio (IAM) tipo 4a tem gerado controvérsia, especialmente com o aumento da sensibilidade nos ensaios de troponina (Tn). Neste estudo, objetivamos quantificar a liberação dos biomarcadores cardíacos em pacientes submetidos à ICP eletiva sem o surgimento de novo realce tardio pelo gadolínio (RTG) na ressonância magnética cardíaca (RMC) após o procedimento. Métodos: Foram incluídos pacientes consecutivos com doença arterial coronária estável e função ventricular preservada, com indicação eletiva para ICP em pelo menos duas artérias epicárdicas. RMC com RTG foi realizada em todos os pacientes antes e depois das intervenções. Medidas seriadas de Tn e creatinoquinase fração MB (CK-MB) foram realizadas imediatamente antes do procedimento até 48 horas após. Pacientes com novo RTG na RMC após o procedimento foram excluídos. Resultados: 71 pacientes foram referenciados para a realização eletiva da ICP sendo que 15 (21,1%) foram excluídos, 10 (14,1%) por causa do surgimento de um novo RTG na RMC após a ICP. Nos 56 pacientes sem a evidência de IAM tipo 4a pela RMC predominava o gênero masculino 37 (66,1%) com idade média de 61,7 (± 8,4) anos e escore de SYNTAX médio de 16,6 (± 7,7). Após a ICP, 48 (85,1%) pacientes apresentaram um pico de elevação de Tn acima do percentil 99 sendo que em 32 (57,1%) a elevação foi superior a 5 vezes esse limite, enquanto que apenas 2 (3,6%) apresentaram um pico de CK-MB maior do que 5 vezes o percentil 99. A mediana do pico de liberação da Tn foi de 0,290 (0,061 - 1,09) ng/mL, valor 7,25 vezes superior ao percentil 99. Conclusão: Diferentemente da CK-MB, a liberação da troponina I ocorre com frequência após procedimento de ICP mesmo na ausência de realce tardio pelo gadolínio na ressonância magnética cardíaca / Background: The release of myocardial necrosis biomarkers after percutaneous coronary intervention (PCI) frequently occurs. However, the correlation between biomarker release and the diagnosis of procedurerelated myocardial infarction (MI) (type 4a) has been controversial. This study aims to evaluate the amount and pattern of cardiac biomarker release after elective PCI in patients without the image of a new MI after the procedure assessed by cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE). Methods: Patients with normal baseline cardiac biomarkers referred for elective PCI were prospectively included. CMR with LGE was performed in all of the patients before and after the interventions. Measurements of troponin I (TnI) and creatinekinase MB fraction (CK-MB) were systematically performed before and after the procedure. Patients with a new LGE on the post-procedure CMR were excluded. Results: Of the 56 patients without the evidence of a procedure-related MI assessed by the CMR after PCI, 48 (85.1%) exhibited a TnI elevation peak above the 99th percentile. In 32 (57.1%), the peak was greater than 5 times this limit. On the other hand, 17 (30.4%) had a CK-MB peak above the limit of the 99th percentile, and this peak was greater than 5 times the 99th percentile in only 2 patients (3.6%). The median peak release of TnI was 0.290 (0.061 to 1.09) ng/ml, which is 7.25-fold higher than the 99th percentile. Conclusions: In contrast to CK-MB, TnI release often occurs after an elective PCI procedure, despite the absence of a new LGE on CMR
107

Auswirkungen der koronaren Kollateralisierung bei Patienten mit akutem ST-Elevations-Myokardinfarkt und primärer perkutaner Koronarintervention

Koch, Alexander 22 May 2014 (has links)
Ziel der Studie war es zu analysieren, welchen Einfluss eine angiographisch sichtbare Kollateralisierung vor Revaskularisation bei Patienten mit einem akuten ST-Elevations-Myokardinfarkt (STEMI) und primärer perkutaner Koronarintervention (PCI) auf verschiedene in der kardialen Magnetresonanztomographie messbare Parameter und auf die klinische Prognose hat. Es wurden 235 Patienten mit STEMI und einem Symptombeginn <12 Stunden in die Analyse eingeschlossen. Alle Patienten wiesen einen funktionell insuffizienten antegraden Fluss in der Infarktarterie auf. Die Patienten wurden in zwei Gruppen unterteilt: Gruppe A mit fehlender oder nur geringer Kollateralversorgung (n=166) und Gruppe B mit einer signifikanten Kollateralisierung (n=69). Es wurden Infarktgröße, mikrovaskuläre Obstruktion und linksventrikuläre Funktion mittels Magnetresonanztomographie im Median 3 Tage nach dem Infarktereignis bestimmt sowie die Patienten über einen Zeitraum von >2 Jahren nachbeobachtet. Das Ausmaß der frühen mikrovaskulären Obstruktion war in Gruppe B signifikant geringer (3,3% gegenüber 2,1% der linksventrikuläre Masse, p = 0,009). Die mittels maximaler Kreatinkinase-MB-Ausschüttung gemessene Infarktgröße war in Gruppe B kleiner (p=0,02). Bei 227 Patienten (97%) wurde nach im Median 2,2 Jahren eine klinische Verlaufskontrolle durchgeführt. Insgesamt starben während des Kontrollzeitraums 25 Patienten: 22 Patienten (13,8%) der Gruppe A mit fehlender oder nur schwacher Kollateralisierung und 3 Patienten (4,4%) der Gruppe B mit signifikanter Kollateralversorgung vor Behandlungsbeginn (p=0,04). In Gruppe A traten 12 (7,5%) nicht-tödliche Reinfarkte auf im Vergleich zu 2 (2,9%) in Gruppe B (p=0,18). Ein kombinierter Endpunkt aus Tod oder nicht-tödlichem Reinfarkt trat in Gruppe B signifikant seltener auf als in Gruppe A (p=0,02). Zusammenfassend lässt sich formulieren, dass gut ausgebildete Kollateralgefäße vor einer Revaskularisation mittels PCI bei Patienten mit akuten STEMI mit einer schützenden Wirkung auf die koronare Mikrozirkulation und einem besseren Langzeit-Überleben assoziiert sind.:1 BIBLIOGRAPHISCHE BESCHREIBUNG 2 ABKÜRZUNGSVERZEICHNIS 3 EINFÜHRUNG 4 AUFGABENSTELLUNG 5 MATERIALIEN UND METHODEN 5.1 Überblick über das Studiendesign 5.2 Koronarintervention 5.3 Enzymatische Infarktgröße 5.4 Kardiale Magnetresonanztomographie 5.4.1 Linksventrikuläre Volumina und Ejektionsfraktion 5.4.2 Infarktgröße 5.4.3 Mikrovaskuläre Obstruktion 5.5 Klinisches Follow-up 5.6 Statistik 6 ERGEBNISSE 6.1 Patientencharakteristika 6.2 Enzymatische Infarktgröße 6.3 Magnetresonanztomographie 6.4 Klinische Ereignisse im Langzeitverlauf 6.5 Prädiktoren klinischer Ereignisse 6.5.1 Univariate Cox-Regressions-Analyse 6.5.2 Multivariate Cox-Regressions-Analyse 6.6 Klinische Ergebnisse in Abhängigkeit von der Zeit zwischen Symptombeginn und Reperfusion 6.7 Magnetresonanztomographische Ergebnisse in Abhängigkeit von der Zeit zwischen Symptombeginn und Reperfusion 7 DISKUSSION 7.1 Limitationen 8 ZUSAMMENFASSUNG DER ARBEIT 9 LITERATURVERZEICHNIS 10 DANKSAGUNG 11 ERKLÄRUNG ÜBER DIE EIGENSTÄNDIGE ABFASSUNG DER ARBEIT 12 LEBENSLAUF 13 PUBLIKATIONEN
108

Auswirkungen der koronaren Kollateralisierung bei Patienten mit akutem ST-Elevations-Myokardinfarkt und primärer perkutaner Koronarintervention

Koch, Alexander 22 May 2014 (has links)
Ziel der Studie war es zu analysieren, welchen Einfluss eine angiographisch sichtbare Kollateralisierung vor Revaskularisation bei Patienten mit einem akuten ST-Elevations-Myokardinfarkt (STEMI) und primärer perkutaner Koronarintervention (PCI) auf verschiedene in der kardialen Magnetresonanztomographie messbare Parameter und auf die klinische Prognose hat. Es wurden 235 Patienten mit STEMI und einem Symptombeginn <12 Stunden in die Analyse eingeschlossen. Alle Patienten wiesen einen funktionell insuffizienten antegraden Fluss in der Infarktarterie auf. Die Patienten wurden in zwei Gruppen unterteilt: Gruppe A mit fehlender oder nur geringer Kollateralversorgung (n=166) und Gruppe B mit einer signifikanten Kollateralisierung (n=69). Es wurden Infarktgröße, mikrovaskuläre Obstruktion und linksventrikuläre Funktion mittels Magnetresonanztomographie im Median 3 Tage nach dem Infarktereignis bestimmt sowie die Patienten über einen Zeitraum von >2 Jahren nachbeobachtet. Das Ausmaß der frühen mikrovaskulären Obstruktion war in Gruppe B signifikant geringer (3,3% gegenüber 2,1% der linksventrikuläre Masse, p = 0,009). Die mittels maximaler Kreatinkinase-MB-Ausschüttung gemessene Infarktgröße war in Gruppe B kleiner (p=0,02). Bei 227 Patienten (97%) wurde nach im Median 2,2 Jahren eine klinische Verlaufskontrolle durchgeführt. Insgesamt starben während des Kontrollzeitraums 25 Patienten: 22 Patienten (13,8%) der Gruppe A mit fehlender oder nur schwacher Kollateralisierung und 3 Patienten (4,4%) der Gruppe B mit signifikanter Kollateralversorgung vor Behandlungsbeginn (p=0,04). In Gruppe A traten 12 (7,5%) nicht-tödliche Reinfarkte auf im Vergleich zu 2 (2,9%) in Gruppe B (p=0,18). Ein kombinierter Endpunkt aus Tod oder nicht-tödlichem Reinfarkt trat in Gruppe B signifikant seltener auf als in Gruppe A (p=0,02). Zusammenfassend lässt sich formulieren, dass gut ausgebildete Kollateralgefäße vor einer Revaskularisation mittels PCI bei Patienten mit akuten STEMI mit einer schützenden Wirkung auf die koronare Mikrozirkulation und einem besseren Langzeit-Überleben assoziiert sind.:1 BIBLIOGRAPHISCHE BESCHREIBUNG 2 ABKÜRZUNGSVERZEICHNIS 3 EINFÜHRUNG 4 AUFGABENSTELLUNG 5 MATERIALIEN UND METHODEN 5.1 Überblick über das Studiendesign 5.2 Koronarintervention 5.3 Enzymatische Infarktgröße 5.4 Kardiale Magnetresonanztomographie 5.4.1 Linksventrikuläre Volumina und Ejektionsfraktion 5.4.2 Infarktgröße 5.4.3 Mikrovaskuläre Obstruktion 5.5 Klinisches Follow-up 5.6 Statistik 6 ERGEBNISSE 6.1 Patientencharakteristika 6.2 Enzymatische Infarktgröße 6.3 Magnetresonanztomographie 6.4 Klinische Ereignisse im Langzeitverlauf 6.5 Prädiktoren klinischer Ereignisse 6.5.1 Univariate Cox-Regressions-Analyse 6.5.2 Multivariate Cox-Regressions-Analyse 6.6 Klinische Ergebnisse in Abhängigkeit von der Zeit zwischen Symptombeginn und Reperfusion 6.7 Magnetresonanztomographische Ergebnisse in Abhängigkeit von der Zeit zwischen Symptombeginn und Reperfusion 7 DISKUSSION 7.1 Limitationen 8 ZUSAMMENFASSUNG DER ARBEIT 9 LITERATURVERZEICHNIS 10 DANKSAGUNG 11 ERKLÄRUNG ÜBER DIE EIGENSTÄNDIGE ABFASSUNG DER ARBEIT 12 LEBENSLAUF 13 PUBLIKATIONEN
109

Metode istraživanja podataka u evaluaciji intra-hospitalnog ishoda obolelih od akutnog infarkta miokarda lečenih primarnom perkutanom koronarnom intervencijom / Data mining methods in evaluation of intra-hospital outcome of patients with acute myocardial infarction treated with primary percutaneous coronary intervention

Sladojević Miroslava 28 September 2016 (has links)
<p>Uvod: Stratifikacija rizika je postala integralna komponenta savremenog pristupa tretmanu u kliničkoj praksi. Danas se u dijagnostici i lečenju akutnog infarkta miokarda (AIM) koriste različiti skorovi rizika kao prognostički instrumenti za kratkoročan i dugoročan ishod bolesti. Nužni proceduralni procesi, u toku primarne perkutane koronarne intervencije (pPKI), kao i saznanja o distribuciji i vrstama lezija koronarnih arterija su od velikog značaja, te se preporučuje finalna evaluacija rizika neposredno nakon izvr&scaron;ene pPKI. Metode istraživanja podataka omogućavaju pronalaženje skrivenih obrazaca u podacima, otkrivanje njihovih uzročno-posledičnih veza I odnosa, te razvoj savremenih prediktivnih modela. Cilj: Kreiranje i testiranje jednostavnog, praktičnog i u svakodnevnoj praksi upotrebljivog prediktivnog modela za procenu intra-hospitalnog ishoda lečenja pacijenata obolelih od AIM sa ST-elevacijom (STEMI) lečenih pPKI. Metode: Istraživanje je unicentrična, retrospektivna, ali I prospektivna studija. U retrospektivnu studiju je uključeno 1495 pacijenta sa STEMI koji su lečeni na Klinici za kardiologiju Instituta za kardiovaskularne bolesti Vojvodine (IKVBV) kod kojih je u cilju rekanalizacije infarktne arterije izvr&scaron;ena pPKI, u periodu od decembra 2008. godine do decembra 2011. godine. Svaki pacijent je inicijalno predstavljen sa 629 obeležja sadržanih u postojećem IKVBV informacionom sistemu, koja čine demografske karakteristike, podaci iz anamneze i kliničkog nalaza, parametri biohemijskih analiza krvi priprijemu, parametri ehokardiografskog pregleda, angiografski i proceduralni detalji i &scaron;ifre prijemnih dijagnoza. U svrhu istraživanja podataka kori&scaron;ćeno je programsko re&scaron;enje otvorenog koda Weka. Tokom evaluacije različitih algoritama izabran je algoritam koji daje najbolje rezultate po tačnosti predikcije i ROC parametru. U sklopu retrospektivnog dela izvr&scaron;ena je validacija prediktivnog modela&nbsp; desetostrukom unakrsnom validacijom na celom skupu podataka. Prospektivnom studijom je na uzorku od 400 pacijenata sa STEMI lečenih pPKI u toku 2015. godine izvr&scaron;ena dodatna validacija razvijenog prediktivnog modela. Za iste pacijente je izračunavat i GRACE skor rizika, te je upoređena njegova, i prediktivna moć razvijenog modela. Rezultati: Alternativno stablo odluke (ADTree) izdvojen je kao algoritam sa najboljim performansama u odnosu na ostale evaluirane algoritme. Cost sensitive klasifikacija je kori&scaron;ćena kao dodatna metodologija da bi se pojačala tačnost. ADTree stablo odluke izdvojilo je osam ključnih parametara koji najvi&scaron;e utiču na ishod intra-hospitalnog lečenja: sistolni krvni pritisak pri prijemu, ejekciona frakcija leve komore, udarni volumen leve komore, troponin, kreatinin fosfokinaza, ukupni bilirubin, T talas i<br />rezultat intervencije. Performanse razvijenog modela su: tačnost predikcije je 93.17%, ROC 0.94. Razvijeni model je na prospektivnoj validaciji zadržao performanse: tačnost predikcije 90.75%, ROC 0.93. &Scaron;iroko kori&scaron;ćeni GRACE skor je na prospektivnom skupu postigao ROC=0.86, &scaron;to pokazuje da je razvijeni prediktivni model superiorniji u odnosu na njega. Zaključak: Razvijeni prediktivni model je jednostavan i pouzdan. Njegova implementacija u svakodnevnu kliničku praksu, omogućila bi kliničarima da izdvoje visokorizične pacijente, nakon reperfuzionog tretmana, a potom kod njih intenziviraju tretman i kliničko praćenje, a sa ciljem smanjenja incidence intra-hospitalnih komplikacija i povećanja njihovog preživljavanja.</p> / <p>Introduction: Risk stratification has become an integral component of modern treatment in clinical practice. Today, the diagnosis and treatment of acute myocardial infarction (AMI) use different risk scores as a prognostic instruments for short-term and long-term outcome of the disease. The necessary procedural processes during primary percutaneous coronary intervention (pPCI) as well as knowledge about the distribution and types of lesions in coronary arteries are of great importance, and a final risk evaluation is recommended directly after the pPCI. Methods of data mining allow finding hidden patterns in data, disclosure of their causal connections and relationships, and the development of modern predictive models. Aim: To create and test a simple, practical and usable predictive model in daily practice for the&nbsp; assessment of intrahospital treatment outcome of patients with AMI with STsegment elevation (STEMI) treated with pPCI. Methods: Presented research is unicentric, retrospective but also prospective study. Retrospective study included 1495 patients with STEMI who were admitted to the Clinics of cardiology of the Institute of Cardiovascular Diseases Vojvodina (IKVBV). For the purpose of recanalization of the infarct artery, pPCI has been performed to these patients during the period from December 2008 to December 2011. Each patient was initially described with 629 attributes from the existing information system of IKVBV. Those attributes consist of demographic characteristics, data from history and clinical findings, biochemical parameters of blood tests on admission, the echocardiographic parameters, angiographic and procedural details and admission diagnosis codes. For model development, an open source software solution Weka was used. During the evaluation of different algorithms, algorithm that gives the best results in terms of accuracy and ROC parameter was chosen. As part of the retrospective study, in order to assess the models performance, ten-fold cross-validation on the entire data set was used. A prospective study, on a sample of 400 patients with STEMI, treated with pPCI in 2015, performed additional validation of the developed predictive model. GRACE risk score was calculated for the prospective study patients and comparison with the developed model has been performed. Results: Alternative decision tree (ADTree) was isolated as an algorithm with the best performance in relation to other algorithms evaluated. Cost sensitive classification was used as an additional methodology to enhance accuracy. ADTree selected eight key parameters that most influence the outcome of intra-hospital treatment: systolic blood pressure on admission, left ventricular ejection fraction, stroke volume of the left ventricle, troponin, creatine phosphokinase, total bilirubin, T wave and the result of the intervention. The performance of the developed model are: the accuracy of the prediction is 93.17%, ROC 0.94. The developed model kept its performance in prospective validation: accuracy of prediction 90.75%, ROC 0.93. Widely used GRACE score achieved ROC = 0.86 in the prospective study patients, indicating that developed predictive model is superior to him. Conclusion: Developed predictive model is simple and reliable. Its implementation in everyday clinical practice, would allow clinicians to distinguish high-risk patients after reperfusion treatment, and then for them to intensify treatment and clinical follow-up, with an aim of reducing the incidence of intra-hospital complications and increase their survival.</p>
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Bridging Knowledge Gaps in the Management of Acute Coronary Syndromes

Huynh Thi, Thanh Thao 04 1900 (has links)
Contexte L’occlusion d’une artère du cœur cause un syndrome coronarien aigu (SCA) soit avec une élévation du segment ST (IAMEST) ou sans élévation du segment ST (1). Le traitement des patients avec un IAMEST requiert soit une intervention coronarienne d’urgence (ICP primaire) ou une thérapie fibrinolytique (FL). La thérapie FL peut être administrée soit dans un contexte pré-hospitalier (PHL) ou à l’hôpital. Une prise en charge précoce des patients avec SCA peut être améliorée par un simple indice de risque. Objectifs Les objectifs de cette thèse étaient de : 1) comparer l’ICP primaire et la thérapie FL (2); décrire plusieurs systèmes internationaux de PHL; (3) développer et valider un indice de risque simplifié pour une stratification précoce des patients avec SCA. Méthodes Nous complétons des méta-analyses, de type hiérarchique Bayésiennes portant sur l’effet de la randomisation, d’études randomisées et observationnelles; complétons également un sondage sur des systèmes internationaux de PHL; développons et validons un nouvel indice de risque pour ACS (le C-ACS). Résultats Dans les études observationnelles, l’ICP primaire, comparée à la thérapie FL, est associée à une plus grande réduction de la mortalité à court-terme; mais ce sans bénéfices concluants à long terme. La FL pré-hospitalière peut être administrée par des professionnels de la santé possédant diverses expertises. Le C-ACS a des bonnes propriétés discriminatoires et pourrait être utilisé dans la stratification des patients avec SCA. Conclusion Nous avons comblé plusieurs lacunes importantes au niveau de la connaissance actuelle. Cette thèse de doctorat contribuera à améliorer l’accès à des soins de qualité élevée pour les patients ayant un SCA. / Background Acute occlusion of an artery of the heart results in acute coronary syndromes (ACS), either with ST-segment elevation (STEMI) or without ST-segment elevation (1). STEMI requires urgent treatment to restore coronary artery flow either by primary percutaneous coronary intervention (PCI) or fibrinolytic therapy (FL) (2). Although several randomized controlled trials (RCTs) demonstrate the superiority of primary PCI in reducing mortality compared to FL (2), the benefit of primary PCI over FL remains uncertain in unselected “real-life” patients (3,4). FL can be administered either in the pre-hospital setting (i.e., pre-hospital FL (PHL)) or at the hospital. PHL is rarely available outside Europe (5,6). Insights into the organization of PHL systems of care may promote more widespread use of PHL. Risk stratification of ACS patients should be prompt to ensure timely PCI for high-risk patients and to avoid unnecessary intervention in low-risk patients (7). Despite the availability of numerous ACS risk scores, there is still no simple risk score that can be easily applied in the initial management of ACS patients (8). Objectives The objectives of this doctoral dissertation were to address these current knowledge gaps in the optimal management of ACS. The objectives were to: 1) evaluate the efficacy, effectiveness, and safety of primary PCI and FL, (2) describe the infrastructure, processes and outcomes of several international PHL systems; and (3) develop and validate a novel clinical risk score for early risk stratification of ACS patients. Methods To address these objectives, I completed Bayesian hierarchical random-effects meta-analyses of published RCTs and observational studies which compare primary PCI and FL in patients with STEMI. I undertook a survey of the infrastructure, processes and outcomes of PHL in several European and North American pre-hospital emergency systems. Finally, I developed and validated an ACS risk score called the Canadian ACS (C-ACS). Results Primary PCI was superior to FL in reducing short-term mortality in RCTs and observational studies. However, the long-term survival benefit of primary PCI was noted only in RCTs, and not in the observational studies. PHL can be effectively delivered by health care professionals with variable levels of expertise. The new risk score, C-ACS, has good discriminant properties for short- and long-term mortality in patients with ACS. Conclusions The first manuscript of this dissertation has been recognized as one of the most valuable recent publications in STEMI management and has contributed to reorganization of STEMI care in Ontario. The other two manuscripts in this dissertation provide practical information and tools for health professionals caring for patients with ACS. In summary, this doctoral dissertation has and will continue to contribute to improve access to high quality care for patients with ACS.

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