Background: Despite the recent improvements in surgical techniques and postoperative patient care, atrial fibrillation (AF) remains the most frequent complication after cardiac surgery. Although postoperative AF is often regarded as a benign clinical condition, this arrhythmia has significant adverse effects on patient recovery and postoperative survival. Its exact pathophysiology has not yet been elucidated. The present thesis aims to analyze AF risk factors and their interaction, pre-existing histological explanatory alterations of the atrium, the AF impact on postoperative survival and the compliance of a prophylactic drug regimen. Methods: During a 10-year period, consecutive cardiac surgery cases with complete data on AF occurrence and postoperative survival were extracted. All patients were operated on for coronary or valvular surgery, with cardiopulmonary bypass (CPB). Hospital and long-term survival data were obtained from Swedish population registry. Study I) Isolated coronary artery bypass grafting (CABG, n=7056), aortic valve replacement (n=690) and their combination (n=688) were considered. Independent AF risk factors and AF effects on early and 1 year mortality were investigated. Study II) Patients affected by postoperative AF among isolated CABG patients (n=7621), valvular surgeries (n=995) and their combination (n=879) were studied. Long-term survival was obtained and prognostic factors identified. Study III) Seventy patients were randomized to on-pump (n=35) or off-pump (n=35) CABG. Samples from the right atrial appendage were collected and histology was evaluated by means of light and electronic microscopy with reference to preexistent alterations related to postoperative AF. Study IV) Cardiac surgery patients with complete data on smoking status (n=3245) were reviewed. Effects of smoking on AF development and interaction among variables were explored. Study V) CABG patients without clinical contraindications to receive oral sotalol (80 mg twice daily) and magnesium were prospectively enrolled (n = 49) and compared with a matched contemporary control CABG group (n = 844). The clinical compliance to the AF prophylactic drug regimen was tested. Results: The overall AF incidence was around 26%, subdivided into 23%, 40% and 45% for isolated CABG, valve procedures and their combined surgeries, respectively. Age was the strongest predictor of postoperative AF. Coronary disease superimposed risk factors with reference to myocardial conditions at CPB weaning. Considering the preoperative smoking condition, smokers demonstrated a reduced AF incidence compared to non-smokers (20% versus 27%, p<0.001). An interaction between smoking status and inotropic support was observed: without this interaction smoking conferred a 46% risk reduction of AF (p=0.011). At the histological level, myocyte vacuolization and nuclear derangement represented anatomical independent AF predictors (p=0.002 and p=0.016, respectively). CPB exposure was not associated to postoperative AF nor histological changes. Although, postoperative AF increases the length of hospitalization in all patient groups, it did not affect the hospital survival. However, AF independently impaired the late survival, a phenomenon seen in the CABG group only. With reference to the tested sotalolmagnesium drug regimen, only 55% of CABG patients were compliant to the treatment, with marginal effects on AF occurrence. Conclusions: In addition to age, details at the CPB weaning period, pre-existing histopathological changes, the hyperadrenergic state and catecholamines are key mechanisms in the pathophysiology of postoperative AF. In particular, the CPB period hides valuable information for timely AF prophylactic stratifications. Further, compliance effects due to patient selection should also be considered in a prophylactic therapy model. Postoperative AF increases late mortality after isolated CABG surgery, but not after valvular procedures. Although the mechanisms are unclear, our results draw the attention to possible AF recurrence after hospital discharge, indicating a strict postoperative surveillance.

No description available.

Contents 1. Introduction 7 1.1. The aim of the study 8 1.2. Tasks of the study 9 1.3. The scientific novelty and originality of the study 9 1.4. Practical importance of the study 9 2. Material and methods 11 2.1. The contingent of studied patients 11 2.2. Methods 12 2.2.1.Coronary artery bypass grafting 12 2.2.2. The used equipment 12 2.2.3. The method of myocardial SPECT performance 12 2.2.4. Evaluation of myocardial SPECT 13 2.3. Statistical analysis of data 15 3. Results 16 3.1. The evaluation of influence of left ventricular ejection fraction on postoperative changes of perfusion of revascularized myocardium 16 3.2. The evaluation of influence of left ventricle ejection fraction on postoperative changes of contraction of revascularized myocardium 18 3.3. The evaluation of influence of collaterals on postoperative changes of perfusion of revasculized myocardium 19 3.4. The evaluation of influence of collaterals on postoperative changes of contraction of revasculized myocardium 21 3.5. The prediction of postoperative myocardial perfusion and contraction 23 3.6. The identification of period of the maximal recovery of myocardial perfusion and contraction after surgical revascularization 27 4. Conclusions 29 5. List of publications 30 6. Summary in Lithuanian 31 7. Autobiography 34 1. Introduction Heart and blood vessels diseases, the most common of which is coronary artery disease (CAD), are the leading causes of death and disability of middle-aged and elderly... [to full text]

Ischemic heart disease is currently the leading cause of death globally. Coronary artery bypass grafting (CABG) is considered the best treatment for many patients and its success depends on the long-term patency of the conduits. Greater use of arterial grafts has been advocated because of their higher long-term patency compared to saphenous vein grafts (SVGs). Despite this, SVGs account for up to 80% of all grafts used in CABG. Consequently, the long-term patency of the saphenous vein (SV) is one of the most crucial challenges in cardiovascular surgery. The no-touch (NT) SV in CABG has shown a superior patency rate, slower progression of atherosclerosis, and better clinical outcome compared to conventional veins up to 8.5 years postoperatively. The aim of this thesis was to study the long-term angiographic, echocardiographic, and clinical aspects of CABG patients receiving either NT or conventional vein grafts and to investigate the health-related quality of life (HRQoL) in this patient group. Studies I-II report a randomized trial between NT and conventional veins where 74 patients were followed-up at a mean of 16 years postoperatively. Study III is a prospective cohort trial in which 97 patients with NT vein grafts anastomosed to the left anterior descending artery (LAD) were included and followed-up at a mean of 6 years postoperatively. Study IV included 257 patients in whom HRQoL and graft patency were studied during the same follow-up visit. Overall, NT vein grafts showed a higher patency compared to conventional veins at a mean of 16 years, 83% vs. 64% (p=0.03), which was similar to the patency of the left internal thoracic artery, 88%. The NT group had a better left ventricular ejection fraction compared to the conventional group, 57.9% vs. 49.4% (p=0.011). After a mean of 6 years, the patency rate of NT SVs to the LAD was 95.6% and to non-LAD targets, 93.9%. Graft patency was an independent predictor of HRQoL in CABG patients. These patients reported a function and wellbeing similar to that of the Swedish population and clearly higher health status than those in the same disease group in the general population.

Die hier vorliegende Studie stellt die Früh- und Langzeitergebnisse der chirurgischen Vorhofablation zur Behandlung des ischämischen Vorhofflimmerns (VHF) in Kombination mit einer aortokoronaren Bypass-Anlage vor. Dabei wurden die epikardiale Pulmonalvenenisolation mittels Radiofrequenzenergie (RF) und die endokardiale Kryoablation inklusive einer Box-Läsion und Mitralisthmuslinie miteinander verglichen. Im Zeitraum von 2002 bis 2009 wurden die prä- und postoperativen Daten von 262 Patienten mit paroxysmalem oder lang-persistierendem VHF prospektiv erhoben und anschließend eine Nachbeobachtung von durchschnittlich 2,30 Jahren durchgeführt. Die Kryoablation war im Vergleich zur RF-Ablation mit einer signifikant höheren perioperativen Invasivität und Morbidität verbunden. Die Operations- und Ischämiezeit sowie die postoperative intensivmedizinische Betreuung waren nach der Kryoablation signifikant länger. Die Rate an Schrittmacherimplantationen (4,8 % vs. 0,0 %), kardialen bzw. zerebralen Komplikationen (22,9 % vs. 12,3 %) und die Krankenhausmortalität (8,4 % vs. 2,2 %) lagen ebenfalls signifikant höher. Hingegen waren die Langzeitergebnisse ohne signifikante Unterschiede zwischen den Ablationsmethoden. Sowohl das Überleben (81,9 % vs. 86,0 %) als auch die Konversionsrate in den Sinusrhythmus (55,6 % vs. 61,5 %), die Lebensqualität der Patienten und die Komplikations- und Reinterventionsraten zeigten im Langzeitverlauf vergleichbare Ergebnisse. Auf der Basis der oben erhobenen Befunde kann die endokardiale Kryoablation nicht als Standardverfahren zur Therapie des paroxysmalen und lang-persistierenden ischämischen VHFs begleitend zu einer aortokoronaren Bypass-Anlage empfohlen werden. Die epikardiale RF-Ablation ist hier aufgrund der geringeren operativen Invasivität bei vergleichbaren Früh- und Langzeitergebnissen der endokardialen Ablation vorzuziehen. :BIBLIOGRAFISCHE ZUSAMMENFASSUNG ABKÜRZUNGSVERZEICHNIS TABELLENVERZEICHNIS ABBILDUNGSVERZEICHNIS 1 EINLEITUNG 1.1 Grundlagen zum Vorhofflimmern 1.1.1 Definition 1.1.2 Epidemiologie 1.1.3 Ätiologie 1.1.4 Klassifikation 1.1.5 Pathophysiologie 1.1.6 Klinik und Komplikationen 1.1.7 Therapieansätze 1.2 Chirurgische Vorhofablation 1.2.1 Entwicklung der VHF-Chirurgie 1.2.2 Indikation 1.2.3 Chirurgische Ablationskonzepte 1.2.4 RF-Ablation 1.2.5 Kryoablation 1.2.6 Alternative Energiequellen 1.3 KHK und operative Revaskularisation bei VHF-Patienten 1.4 Ziele der Arbeit und Fragestellung´ 2 MATERIAL UND METHODEN 2.1 Patientenkollektiv 2.2 Erfassung der Patientenvariablen 2.3 Definition der Endpunkte 2.4 Operations- und Ablationstechnik 2.5 Postoperatives Management 2.6 Follow-Up 2.7 Statistische Auswertung 3 ERGEBNISSE 3.1 Patienten mit paroxysmalem VHF 3.1.1 Patientencharakteristik 3.1.2 Operative Ergebnisse 3.1.3 Postoperative Ergebnisse und Komplikationen 3.1.4 Zustand bei Krankenhausentlassung 3.1.5 Ergebnisse der Langzeitbeobachtung 3.2 Patienten mit lang-persistierendem VHF 3.2.1 Patientencharakteristik 3.2.2 Operative Ergebnisse 3.2.3 Postoperative Ergebnisse und Komplikationen 3.2.4 Zustand bei Krankenhausentlassung 3.2.5 Ergebnisse der Langzeitbeobachtung 3.3 Ausgewählte Vergleiche von Patienten mit paroxysmalem und mit lang-persistierendem VHF 3.3.1 Patientencharakteristik 3.3.2 Operative Ergebnisse 3.3.3 Zustand bei Krankenhausentlassung 3.3.4 Ergebnisse der Langzeitbeobachtung 3.4 Ausgewählte Vergleiche von Patienten mit RF- und Kryoablation 3.4.1 Patientencharakteristik 3.4.2 Operative Ergebnisse 3.4.3 Postoperative Ergebnisse und Komplikationen 3.4.4 Zustand bei Krankenhausentlassung 3.4.5 Ergebnisse der Langzeitbeobachtung 4 DISKUSSION 4.1 Bezug zur Fragestellung 4.2 Einfluss des ischämischen VHFs 4.3 Einfluss des Ablationskonzepts 4.4 Einfluss der Ablationsenergie 4.4.1 Herzspezifische Laborparameter 4.4.2 Postoperative Verlaufsparameter 4.4.3 Ergebnisse der Langzeitbeobachtung 4.5 Schlussfolgerung und Ausblick 4.6 Limitationen 6 ZUSAMMENFASSUNG DER ARBEIT 7 LITERATURVERZEICHNIS 8 ANLAGEN SELBSTÄNDIGKEITSERKLÄRUNG PUBLIKATIONEN DANKSAGUNG

京都大学 / 新制・課程博士 / 博士(医学) / 甲第24474号 / 医博第4916号 / 新制||医||1062(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 石見 拓, 教授 永井 洋士, 教授 大鶴 繁 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Justificativa e objetivos: Estudo longitudinal, prospectivo, randomizado para avaliar a influência do uso de um ou dois drenos pleuromediastinais na dor pós-operatória, na função pulmonar e na liberação de interleucinas pró-inflamatórias dos pacientes submetidos à revascularização do miocárdio. Casuística e método: 33 pacientes escalados para cirurgia eletiva de revascularização do miocárdio, com uso de CEC, foram alocados por sorteio em dois grupos: grupo GDU (dreno único) e grupo GDD (dreno duplo). No período pósoperatório foram avaliadas a intensidade da dor, a performance ventilatória por meio das medidas da CVF e da VEF1 e foram quantificadas as concentrações de interleucinas nos três primeiros dias do período pós-operatório. Resultados: 33 pacientes analisados, 16 no grupo GDU e 17 no grupo GDD. O grupo GDU apresentou valores espirométricos maiores que o grupo GDD (p<0,001) no pós-operatório, denotando menor interferência do dreno na respiração. A PaO2 arterial, no primeiro e segundo PO, aumentou significantemente no grupo GDU quando comparada com o grupo GDD (p<0,001). A intensidade da dor no grupo GDU, antes e após a espirometria, foi menor que no grupo GDD (p<0,001). Houve aumento significativo dos valores espirométricos em ambos os grupos, após a retirada do dreno pleural. As variações das concentrações de interleucina não foram significativas quando se compararam valores intra e intergrupos, embora tenha havido uma tendência a aumento da IL- 6, no primeiro dia de pós-operatório no grupo GDD. Conclusão: O uso de apenas um dreno torácico altera menos a função pulmonar, possibilita uma melhor recuperação dos parâmetros respiratórios, além de mostrar eficácia semelhante a dois drenos na drenagem torácica. / BACKGROUND AND OBJECTIVES: A prospective, randomized, longitudinal study to evaluate the influence of one or two pleuromediastinal drains on postoperative pain, pulmonary function, and the release of proinflammatory interleukins from patients undergoing myocardial revascularization. Patients and methods: 33 patients who underwent elective coronary artery bypass grafting (CABG) were randomized into two groups: GDU group (single drain) and GDD group (double drain). In the postoperative period, pain intensity, ventilatory performance were measured through FVC and FEV1 measurements, and interleukin concentrations were quantified in the first three days of the postoperative period. Results: 33 patients were analyzed, 16 in the GDU group and 17 in the GDD group. The GDU group presented higher spirometric values than the GDD group (p <0.001) in the postoperative period, indicating less interference of the drain in the breath. The arterial PaO2, in the first and second PO, increased significantly in the GDU group when compared to the GDD group (p <0.001). The pain intensity in the GDU group, before and after spirometry, was lower than in the GDD group (p <0.001). There was a significant increase in spirometric values in both groups, after the pleural drainage was removed. Variations in interleukin concentrations were not significant when comparing intra and intergroup values, although there was a tendency for IL-6 to increase on the first postoperative day in the GDD group. Conclusion: The use of only one thoracic drainage modifies pulmonary function less, allows better recovery of respiratory parameters, and shows similar efficacy to two drains in the thoracic drainage.

A artéria radial (AR) constitui valiosa opção de enxerto na revascularização do miocárdio (RM), desde a retomada de seu uso, nos anos 1990. O objetivo deste estudo foi avaliar perviedade e remodelamento dos enxertos de AR e sua relação com lesão obstrutiva pré-operatória e parede miocárdica revascularizada, observando-se também os enxertos de artéria torácica interna (ATI). CASUÍSTICA E MÉTODO: Entre 1994 e 2007, 3.964 pacientes foram operados com uso da AR, no InCor/HCFMUSP. Foram selecionados os reestudos angiográficos (12 meses) de 100 pacientes, sendo 11 deles reestudados em duas épocas diferentes. Em 92 pacientes foi utilizada a ATI. Foram determinados os diâmetros médios de AR e ATI, através do software CASS-II®. RESULTADOS: O tempo médio de reestudo foi de 70,53 ±33,18 meses. Em 82 casos (82,0%), a AR revascularizou uma única coronária, mais freqüentemente (50,83%) os ramos marginal esquerdo (ME) ou ventricular posterior (VP/CX). As obstruções pré-operatórias entre 90 e 99% foram as mais prevalentes (39,0%). A perviedade observada foi de 80 casos para AR (80,0%) e 80 para ATIE (86,96%). Houve correlação entre as maiores obstruções pré-operatórias e maior perviedade da AR (p=0,024). Os diâmetros médios dos enxertos foram de 2,302mm ±0,479 (AR) e 2,262mm ±0,409 (ATI). Observaram-se AR maiores do que a média (>2,30mm) nas obstruções pré-operatórias de 100%, em comparação com as demais (p=0,017). As AR que revascularizaram a parede lateral apresentaram os maiores diâmetros, em comparação às demais (p=0,04). Nos 11 pacientes com 2 reestudos, os diâmetros médios das AR foram de: 2,482mm ±0,424 (primeiro reestudo) e 2,599mm ±0,532 (segundo reestudo)(p=n/s). Para as ATIE, observaram-se: 2,308mm ±0,459 (primeiro reestudo) e 2,326mm ±0,531 (segundo reestudo) (p=n/s). No segundo reestudo, observou-se maior número de AR com diâmetros maiores, relacionados às obstruções entre 90-100% (p=0,013). A parede miocárdica revascularizada não interferiu nos diâmetros dos enxertos. CONCLUSÕES: A obstrução pré-operatória interfere na perviedade e nos diâmetros dos enxertos de AR, especialmente nas obstruções de 90% ou mais. A parede miocárdica revascularizada não interfere na perviedade da AR, porém interfere nos diâmetros dos enxertos. Foi observado remodelamento dos enxertos de AR, estando as obstruções mais graves relacionadas aos maiores aumentos de diâmetros dos enxertos comportamento semelhante às ATI. / The radial artery (RA) is an invaluable option for coronary artery bypass grafting (CABG), since its re-introduction in the late 1990 s.The objective of this study was to assess patency and remodeling of RA grafts regarding the interference of pre-operative coronary obstruction and grafted myocardial wall, also observing the internal thoracic artery grafts (ITA). METHODS: Between 1994 and 2007, 3,964 patients were operated with RA grafts, at Heart Institute, University of São Paulo, Brazil. Post-operative coronary angiographies (12 months)of 100 patients were obtained, including 11 patients with two post-op exams, at different periods. In 92 patients the ITA was also used.The grafts medium diameters were obtained using the CASS-II® software. RESULTS: Mean time of post-op angiography was 70,53 ±33,18 months. In 82 cases (82,0%) the RA grafted a single coronary, more frequently (50,83%) the left marginal (LM) or posterior ventricular (PV) branches. Pre-op obstructions between 90 and 99% were more prevalent (39,0%). Patency was of 80 cases for the RA (80,0%) and 80 cases for the ATI grafts (86,96%). There was a correlation between more severe pre-op obstructions and greater patency of the RA grafts (p=0,024). The mean diameters were 2,302mm ±0,479 (RA) and 2,262mm ±0,409 (ITA). RA diameters were above the mean value (>2,30mm) in pre-op obstructions of 100%, compared to the rest (p=0,017). The RA grafting the lateral wall showed the larger diameters, compared to the rest (p=0,04). For the 11 patients with 2 post-op angiographies, mean diameters of RA grafts were: 2,482mm ±0,424 (first) and 2,599mm ±0,532 (second)(p=n/s). For ITA grafts, mean diameters were: 2,308mm ±0,459 (first) and 2,326mm ±0,531 (second)(p=n/s). For the second angiographies, RA grafts exhibited larger diameters, related to pre-op obstructions between 90 and 100% (p=0,013). The grafted myocardial wall showed no interference with graft diameter. CONCLUSIONS: Pre-op coronary obstruction interferes in patency and diameters of RA grafts, more evidently for obstructions of 90% or greater. The grafted myocardial wall does not interfere with RA patency, although it does interfere with graft diameter. Remodeling was observed in RA grafts, correlating greater pre-op coronary obstructions and more evident increase in graft diameter similarly to the ITA grafts.

Faktoren, die die funktionelle Erholung von hibernating myocardium nach aortokoronarem Venen Bypass (ACVB) beeinflussen, werden gegenwärtig untersucht. Von 3/2000 bis 3/2003 untersuchten wir prospektiv 41 Patienten mit einer linksventrikulären Ejektionsfraktion (LVEF) / Objectives: Factors that influence functional recovery of hibernating myocardium after coronary artery bypass grafting are at present under investigation. Methods: From 3/2000 to 3/2003 we prospectively analyzed 41 patients with ejection fraction (EF) 15% during DE in group I preoperatively; the increase was < 15% in group II. MRI hyperenhancement was measured with a mean of 16,7±11,6% of the left ventricle in group I compared to a mean of 27,4±14,4% in group II (p 19µm) in group I than in group II (< 17µm). Gene expression of pro-apoptotic genes such as BAK and BAX was lowered (0.5±0.1/0.8±0.1) compared to "normal" myocardium (1.0±0.1) (p

Background: The 30-day readmission rate is considered a quality of care measure for providers and has become important because providers might face reduced reimbursement from any increase in unplanned readmissions Objective: The aim of the first chapter is to investigate the waiting-length of stay (WLOS) and post-length of stay (PLOS) on the 30-day readmission. In the second chapter, we examined the hospital procedural volume and hospital quality on the 30-day readmission. Our objective in the third chapter is to examine the zip code-level SES factors on the 30-day readmission rates. Participants: patients undergoing isolated coronary artery bypass grafting (CABG) in Virginia Methods: A retrospective study design has been conducted using a multi-level logistic model of increasing complexity for all three chapters. The sample used was from the Virginia Cardiac Surgery Quality Initiative (VCSQI) of the periods 2008-2014, the dataset included patient characteristics. Afterward, we merged the sample with both the Virginia Health Information (VHI) to obtain hospital characteristics (ownership, teaching status, and location), and Agency for Healthcare Research and Quality (AHRF) to obtain county-socio-economic status (SES) characteristics (education, employment, and median household income), the previous SES was used for chapter’s one and two. In chapter three, instead of AHRF, we merged the sample with the American Community Survey (ACS) to obtain zip code-SES characteristics (employment, median household income, education, median house price). The main outcome was the 30-day readmission rate. The analytical sample of chapter one n = 22,097, in chapter two the sample n = 25,531, while in chapter three the sample n= 25,829. We conducted a sensitivity analysis in all three chapters. In chapter one we analyzed the data at the patient level, in chapter two we analyzed the data at the hospital level, while in chapter three we conducted the analysis at the area zip code level. Results: In chapter one, we found that readmitted patients after a prolonged PLOS had increased odds of readmission, by 68.7%, compared to readmitted patients with a shorter PLOS in the fully adjusted model; while, WLOS was not significant at the P < 0.05. In chapter two, the fully adjusted model displayed significant results with a reduced odds in readmissions by 22.8% in the middle-volume hospitals compared to the low-volume hospitals, while the middle-quality hospitals had increased odds of readmission by 23.5% compared to the low-quality hospitals. In chapter three, statistically, we did not find that area zip code-SES had an effect on the 30-day readmission rate. While, geographically, we found that addresses of individuals were clustered in certain areas of Virginia. Conclusion: In chapter one, patients undergoing CABG and experience a prolonged PLOS of > 6 days are at risk to be readmitted within 30-days of the procedure. In chapter two, the higher volume hospitals (middle-volume) compared to low-volume hospitals showed a significant reduction in odds in the 30-day readmissions, especially after adjusting the model with hospital quality. In chapter three, even though, there was no association of area-SES with 30-day readmission, in the maps, we found a cluster of patient addresses in the southern parts of Virginia with an increased readmission, which is considered underprivileged area; and the fact might be due to the proximity of these areas to cardiovascular hospitals. Policy Implication: In chapter one, the study provided a model for clinicians to stratify patients at risk of readmission, especially patients with risks of staying longer in the hospital after CABG. In chapter two, policymakers and the CMS should find new ways to help hospitals with low-volumes to reduce their isolated-CABG readmission rates and be able to compete with high-volume hospitals. In chapter three, no significant correlation between area-SES and readmission for patients who underwent CABG was found; these backs prior notion that SES should not be adjusted for the reimbursement penalties of the Hospital Readmission Reductions Program (HRRP) on hospitals