{"id":{"repo_id":"varna","oai_identifier":"oai:repository.mu-varna.bg:nls/4170"},"canonical_url":"https://search.dev.ndltd.org/etd/varna/oai:repository.mu-varna.bg:nls/4170","repository":{"repo_id":"varna","name":"Medical University of Varna","base_url":"https://repository.mu-varna.bg/oai/request"},"display":{"title":"Early Postoperative Complications in Open Cardiac Surgery. A Current Strategy for Prediction and Risk Stratification // Ранни постоперативни усложнения при отворена сърдечна хирургия – съвременен подход за предикция и стратифициране на риска","abstract":"Open-heart surgery remains one of the primary methods for treating various cardiovascular diseases. Despite advances in surgical technique, like any surgical intervention, these procedures carry the risk of various complications that determine patient survival and quality of life. Accurate risk stratification for such complications enables optimisation of the perioperative approach and improvement of prognosis. The thesis aims to develop optimal models for defining the risk of early postoperative complications, including atrial fibrillation, significant bleeding, delirium, acute kidney injury and death after open cardiac surgery. A retrospective cohort study was conducted, encompassing patients who underwent coronary artery bypass graft surgery, valve surgery, or combined bypass and valve surgery at the Cardiac Surgery Clinic of St. Marina University Hospital in Varna from March 2017 to March 2020. Data on a total of 120 variables were collected for each patient, covering the preoperative, intraoperative, and postoperative periods. Using univariate and multivariate logistic regression methods, an attempt was made to predict the occurrence of newly developed atrial fibrillation, significant bleeding, delirium, acute renal injury, and death in the early postoperative period after cardiac surgery.","abstract_html":"Open-heart surgery remains one of the primary methods for treating various cardiovascular diseases. Despite advances in surgical technique, like any surgical intervention, these procedures carry the risk of various complications that determine patient survival and quality of life. Accurate risk stratification for such complications enables optimisation of the perioperative approach and improvement of prognosis. The thesis aims to develop optimal models for defining the risk of early postoperative complications, including atrial fibrillation, significant bleeding, delirium, acute kidney injury and death after open cardiac surgery. A retrospective cohort study was conducted, encompassing patients who underwent coronary artery bypass graft surgery, valve surgery, or combined bypass and valve surgery at the Cardiac Surgery Clinic of St. Marina University Hospital in Varna from March 2017 to March 2020. Data on a total of 120 variables were collected for each patient, covering the preoperative, intraoperative, and postoperative periods. Using univariate and multivariate logistic regression methods, an attempt was made to predict the occurrence of newly developed atrial fibrillation, significant bleeding, delirium, acute renal injury, and death in the early postoperative period after cardiac surgery.","abstract_has_math":false,"creators":["Bachvarov, Georgi","Бъчваров, Георги"],"institution":"Medical University of Varna","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025-09-30T13:16:54Z","date_published":"2025-09-30T13:16:54Z","updated_at":"2026-07-27T21:56:59Z","subjects":["open-heart surgery","postoperative complications","risk stratification","Хирургия / Surgery"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://repository.mu-varna.bg/handle/nls/4170","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Bachvarov, Georgi","Бъчваров, Георги"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2025-09-30T13:16:54Z","2025"]},{"key":"dc:publisher","label":"Institution","values":["Medical University of Varna"]},{"key":"dc:type","label":"Dc Type","values":["thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["open-heart surgery","postoperative complications","risk stratification","Хирургия / Surgery"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://repository.mu-varna.bg/handle/nls/4170"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Open-heart surgery remains one of the primary methods for treating various cardiovascular diseases. Despite advances in surgical technique, like any surgical intervention, these procedures carry the risk of various complications that determine patient survival and quality of life. Accurate risk stratification for such complications enables optimisation of the perioperative approach and improvement of prognosis. The thesis aims to develop optimal models for defining the risk of early postoperative complications, including atrial fibrillation, significant bleeding, delirium, acute kidney injury and death after open cardiac surgery. A retrospective cohort study was conducted, encompassing patients who underwent coronary artery bypass graft surgery, valve surgery, or combined bypass and valve surgery at the Cardiac Surgery Clinic of St. Marina University Hospital in Varna from March 2017 to March 2020. Data on a total of 120 variables were collected for each patient, covering the preoperative, intraoperative, and postoperative periods. Using univariate and multivariate logistic regression methods, an attempt was made to predict the occurrence of newly developed atrial fibrillation, significant bleeding, delirium, acute renal injury, and death in the early postoperative period after cardiac surgery.","Отворената сърдечна хирургия остава един от основните методи за лечение на редица сърдечно-съдови заболявания. Въпреки развитието в оперативната техника, както при всяка оперативна интервенция и тези операции са свързани с риск от редица усложнения, които са предопределящи за преживяемостта и качеството на живот на пациентите. Коректното стратифициране на риска от такива усложнения дава възможност за оптимизиране на периоперативния подход и подобряване на прогнозата. Целта на дисертационния труд беше да предложи оптимални модели за дефиниране на риска от новопоявило се предсърдно мъждене, значимо кървене , изява на делир, остра бъбречна увреда и смърт в ранния следоперативен период след сърдечна операция. Бе проведено ретроспективно кохортно проучване, обхващащо пациенти преминали аорто-коронарен байпас хирургия, клапна хирургия или комбинирана байпаси и клапна операция в Клиника по кардиохирургия на УМБАЛ Света Марина Варна в периода месец март 2017 до месец март 2020 година. При всеки пациент бяха събрани данни за общо 120 показатели, касаещи пред-, интра- и постоперативния период Чрез метода на едномерна и многомерна логистична регресия, сред всички анализирани показатели беше потърсена възможност за предикция изявата на новопоявило се предсърдно мъждене, значимо кървене , изява на делир, остра бъбречна увреда и смърт в ранния следоперативен период след сърдечна операция."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Early Postoperative Complications in Open Cardiac Surgery. A Current Strategy for Prediction and Risk Stratification // Ранни постоперативни усложнения при отворена сърдечна хирургия – съвременен подход за предикция и стратифициране на риска"]}]}],"canonical_facts":{"dc:creator":["Bachvarov, Georgi","Бъчваров, Георги"],"dc:date":["2025-09-30T13:16:54Z","2025"],"dc:description":["Open-heart surgery remains one of the primary methods for treating various cardiovascular diseases. Despite advances in surgical technique, like any surgical intervention, these procedures carry the risk of various complications that determine patient survival and quality of life. Accurate risk stratification for such complications enables optimisation of the perioperative approach and improvement of prognosis. The thesis aims to develop optimal models for defining the risk of early postoperative complications, including atrial fibrillation, significant bleeding, delirium, acute kidney injury and death after open cardiac surgery. A retrospective cohort study was conducted, encompassing patients who underwent coronary artery bypass graft surgery, valve surgery, or combined bypass and valve surgery at the Cardiac Surgery Clinic of St. Marina University Hospital in Varna from March 2017 to March 2020. Data on a total of 120 variables were collected for each patient, covering the preoperative, intraoperative, and postoperative periods. Using univariate and multivariate logistic regression methods, an attempt was made to predict the occurrence of newly developed atrial fibrillation, significant bleeding, delirium, acute renal injury, and death in the early postoperative period after cardiac surgery.","Отворената сърдечна хирургия остава един от основните методи за лечение на редица сърдечно-съдови заболявания. Въпреки развитието в оперативната техника, както при всяка оперативна интервенция и тези операции са свързани с риск от редица усложнения, които са предопределящи за преживяемостта и качеството на живот на пациентите. Коректното стратифициране на риска от такива усложнения дава възможност за оптимизиране на периоперативния подход и подобряване на прогнозата. Целта на дисертационния труд беше да предложи оптимални модели за дефиниране на риска от новопоявило се предсърдно мъждене, значимо кървене , изява на делир, остра бъбречна увреда и смърт в ранния следоперативен период след сърдечна операция. Бе проведено ретроспективно кохортно проучване, обхващащо пациенти преминали аорто-коронарен байпас хирургия, клапна хирургия или комбинирана байпаси и клапна операция в Клиника по кардиохирургия на УМБАЛ Света Марина Варна в периода месец март 2017 до месец март 2020 година. При всеки пациент бяха събрани данни за общо 120 показатели, касаещи пред-, интра- и постоперативния период Чрез метода на едномерна и многомерна логистична регресия, сред всички анализирани показатели беше потърсена възможност за предикция изявата на новопоявило се предсърдно мъждене, значимо кървене , изява на делир, остра бъбречна увреда и смърт в ранния следоперативен период след сърдечна операция."],"dc:format":["application/pdf"],"dc:identifier":["http://repository.mu-varna.bg/handle/nls/4170"],"dc:publisher":["Medical University of Varna"],"dc:subject":["open-heart surgery","postoperative complications","risk stratification","Хирургия / Surgery"],"dc:title":["Early Postoperative Complications in Open Cardiac Surgery. A Current Strategy for Prediction and Risk Stratification // Ранни постоперативни усложнения при отворена сърдечна хирургия – съвременен подход за предикция и стратифициране на риска"],"dc:type":["thesis"]},"updated_at":"2026-07-27T21:56:59Z"}