Repositório RCAAP

Objective: To analyze the results of 125 carotid endarterectomies under loco-regional anesthesia, with selective use of shunt and bovine pericardium patch. Methods: One hundred and seventeen patients with stenosis ≥ 70% in the internal carotid artery on duplex-scan + arteriography or magnetic resonance angiography underwent 125 carotid endarterectomies. Intraoperative pharmacological cerebral protection included intravenous administration of alfentanil and dexametasone. Clopidogrel, aspirin and statins were used in all cases. Seventy-seven patients were males (65.8%). Mean age was 70.8 years, ranging from 48 to 88 years. Surgery was performed to treat symptomatic stenosis in 69 arteries (55.2%) and asymptomatic stenosis in 56 arteries (44.8%). Results: A carotid shunt was used in 3 cases (2.4%) due to signs and symptoms of cerebral ischemia after carotid artery clamping during the operation, and all 3 patients had a good outcome. Bovine pericardium patch was used in 71 arteries ≤ 6 mm in diameter (56.8%). Perioperative mortality was 0.8%: one patient died from a myocardial infarction. Two patients (1.6%) had minor ipsilateral strokes with good recovery, and 2 patients (1.6%) had non-fatal myocardial infarctions with good recovery. The mean follow-up period was 32 months. In the late postoperative period, there was restenosis in only three arteries (2.4%). Conclusion: Carotid artery endarterectomy can be safely performed in the awake patient, with low morbidity and mortality rates.

Objective: Postoperative atrial fibrillation is a common complication after cardiac surgery, with an incidence as high as 20-50%. Increased age is associated with a significant increase in postoperative atrial fibrillation risk. This common complication is associated with higher morbidity and mortality rates. The aim of this study was to assess the efficacy of nebivolol in preventing atrial fibrillation following coronary artery bypass surgery in patients over 60 years of age. Methods: In this prospective randomized study, 200 patients who were candidates for elective coronary artery bypass surgery were divided into two groups. The first group was administered with nebivolol and the second group was administered with metoprolol. Treatment was initiated four days prior to surgery, and patients were monitored for atrial fibrillation until discharge. Forty-one patients recieved 50 mg metoprolol succinate daily, which was initiated minimum 4 days before surgery. Results: Demographic data were similar in both groups. The incidence of postoperative atrial fibrillation in both groups was similar, with no significant difference being identified [n=20 (20%); n=18 (18%), P=0.718; respectively]. There were not any mortality at both groups during study. Inotropic agent requirement at ICU was similar for both groups [n=12 (12%), n=18 (18%), P=0.32]. Conclusion: We compared the effectiveness of nebivolol and metoprolol in decreasing the incidence of postoperative atrial fibrillation, and determined that nebivolol was as effective as metoprolol in preventing postoperative atrial fibrillation at patients. Nebivolol may be the drug of choice due to its effects, especially after elective coronary artery bypass surgery.

Objective: To evaluate the lung function and clinical outcome in severe chronic obstructive pulmonary disease in patients undergoing off-pump coronary artery bypass grafting with left internal thoracic artery graft, comparing the pleural drain insertion in the intercostal versus subxyphoid region. Methods: A randomized controlled trial. Chronic obstructive pulmonary disease patients were randomized into two groups according pleural drain site: II group (n=27) - pleural drain in intercostal space; SI group (n=29) - pleural drain in the subxyphoid region. Spirometry values (Forced Vital Capacity - and Forced expiratory volume in 1 second) were obtained on preoperative and 1, 3 and 5 postoperative days. Chest x-ray from preoperative until postoperative day 5 (POD5) was performed for monitoring respiratory events, such as atelectasis and pleural effusion. Pulmonary shunt fraction and pain score was evaluate preoperatively and on postoperative day 1. Results: In both groups there was a significant decrease of the spirometry values (Forced Vital Capacity and Forced expiratory volume in 1 second) until POD5 (P<0.05). However, when compared, SI group presented less decrease in these parameters (P<0.05). Pulmonary shunt fraction was significantly lower in SI group (P<0.05). Respiratory events, pain score, orotracheal intubation time and postoperative length of hospital stay were lower in the SI group (P<0.05). Conclusion: Subxyphoid pleural drainage in severe Chronic obstructive pulmonary disease patients determined better preservation and recovery of pulmonary capacity and volumes with lower pulmonary shunt fraction and better clinical outcomes on early postoperative off-pump coronary artery bypass grafting.

Objetivo: Comparar a eficácia do AAS e da Varfarina na profilaxia da trombose em pacientes submetidos a operação cavopulmonar total. Avaliar se fatores de coagulação (VII, VIII e Proteína C), dados clínicos, fenestração ou fatores hemodinâmicos, interferem na trombose no pós-operatório. Métodos: Estudo prospectivo e randomizado de 30 pacientes, randomizados em Grupo I (Varfarina) e Grupo II (AAS), submetidos à derivação cavopulmonar total com tubo extracardíaco, entre 2008 e 2011, com seguimento de dois anos. Foram realizadas consultas clínicas que avaliavam efeitos colaterais e aderência. Realizado ecocardiograma transesofágico no pós-operatório imediato, 3, 6,12 e 24 meses; angiotomografia aos 6, 12 e 24 meses de pós-operatório para avaliação de alterações na parede interna do tubo ou trombos e cintilografia pulmonar, para avaliar possível TEP. Resultados: Dois óbitos no grupo I; 33,3% dos pacientes apresentaram trombo (46,7% no Grupo II). A ocorrência prévia de trombo e baixos níveis de proteína C da coagulação foram os únicos fatores que influenciaram no tempo livre de trombo (P=0,035 e 0,047). Avaliação angiotomográfica: 35,7% dos pacientes do grupo II tinham atapeteamento maior que 2 mm (P=0,082). Cintilografia: dois pacientes apresentaram TEP no grupo II. Cinco pacientes tiveram dificuldade de aderência, 4 no grupo I com INR variando de 1 a 6,4. Conclusão: A ocorrência prévia de trombo é um fator de risco para trombose no pós-operatório. Pacientes em uso de AAS tendem a depósito de material na parede do tubo. O número reduzido da amostra não permitiu concluir qual a droga mais eficaz na prevenção da trombose na população estudada.

Introdução: O sangue alogênico é um recurso terapêutico esgotável. Novas evidências demonstram um consumo excessivo de sangue e uma diminuição das doações, resultando em estoques de sangue reduzidos em todo o mundo. As transfusões de sangue estão relacionadas a aumento na morbimortalidade e maiores custos hospitalares. Deste modo, torna-se necessário procurar outras opções de tratamento. Estas alternativas existem, porém são pouco conhecidas e raramente utilizadas. Objetivo: Reunir e descrever de maneira sistemática, objetiva e prática todas as estratégias clínicas e cirúrgicas, como opções terapêuticas eficazes para minimizar ou evitar transfusões de sangue alogênico e seus efeitos adversos nos pacientes submetidos à cirurgia cardíaca. Métodos: Foi efetuada uma pesquisa bibliográfica com busca ao descritor “Blood transfusion” (MeSH) e aos termos “Cardiac surgery” e “Blood management”. Estudos com títulos não relacionados diretamente ao tema da pesquisa, estudos que não continham nos resumos dados relacionados à pesquisa, estudos mais antigos que relataram estratégias repetidas foram excluídos. Resultados: Tratar anemia e plaquetopenia, suspender anticoagulantes e antiplaquetários, reduzir flebotomias rotineiras, técnica cirúrgica menos traumática com hipotermia e hipotensão moderada, hemostasia meticulosa, uso de agentes hemostáticos sistêmicos e tópicos, hemodiluição normovolêmica aguda, recuperação sanguínea intraoperatória, tolerância à anemia (oxigênio suplementar e normotermia), bem como várias outras opções terapêuticas mostram ser estratégias eficazes em reduzir transfusões de sangue alogênico. Conclusão: Existem múltiplas estratégias clínicas e cirúrgicas para otimizar a massa eritrocitária e o estado de coagulação, minimizar a perda de sangue e melhorar tolerância à anemia. Estes recursos terapêuticos deveriam ser incorporados à prática médica mundial, visando diminuir o consumo de hemocomponentes, reduzir a morbimortalidade e custos hospitalares.

Objective: Anomalous origin of coronary artery is uncommon. The taxonomies of anomalous origin of coronary artery are inconsistent and complex. Conceptual and therapeutic debates remain. The aim of the present study is to reappraise the concept of anomalous origin of coronary artery and to discuss the potential hazards and treatment rationale of this anomaly on basis of literature review. Methods: A comprehensive literature review was made in terms of the taxonomies including “simple”, “multiple” and “complex” types of anomalous origin of coronary artery. Results: Anomalous origin of coronary artery can be simply categorized according to the ectopically originated coronary artery. There are a couple of complex anatomical variants: “multiple” type, involving more than one coronary artery or branch, which can be subdivided into 2 subtypes, A) more than one coronary arteries or branches arising from one place; and B) two coronary arteries/branches arising from separate ectopic sites; and “complex” type, associated with acquired heart disease, or congenital heart defects. Conclusion: Sudden cardiac death in anomalous origin of coronary artery is associated with the anatomical features including abnormal coursing, acute angle take-off and ostial abnormalities. Atherosclerosis is prone to be in the right-sided ectopic and retroaortic coursing coronary artery. Surgical treatment is a definitive therapy. Simple coronary artery bypass grafting is not recommended due to the potential hazards of coronary steal phenomenon and poor patency of mammary arterial grafts, and modified maneuvers such as coronary ostial reimplantation, impinged coronary segment unroofing and coronary stent deployment are advocated instead.

Objective: The present study is to describe the clinical impact of S100 and S100β for the evaluation of cerebral damage in cardiac surgery with or without the use of cardiopulmonary bypass (CPB). Methods: Quantitative results of S100 and S100β reported in the literature of the year range 1990-2014 were collected, screened and analyzed. Results: Cerebrospinal fluid and serum S100 levels showed a same trend reaching a peak at the end of CPB. The cerebrospinal fluid/serum S100 ratio decreased during CPB, reached a nadir at 6 h after CPB and then increased and kept high untill 24 h after CPB. Serum S100 at the end of CPB was much higher in infant than in adults, and in on-pump than in off-pump coronary artery bypass patients. ∆S100 increased with age and CPB time but lack of statistical significances. Patients receiving an aorta replacement had a much higher ∆S100 than those receiving a congenital heart defect repair. Serum S100β reached a peak at the end of CPB, whereas cerebrospinal fluid S100 continued to increase and reached a peak at 6 h after CPB. The cerebrospinal fluid/serum S100β ratio decreased during CPB, increased at the end of CPB, peaked 1 h after CPB, and then decreased abruptly. The increase of serum S100β at the end of CPB was associated with type of operation, younger age, lower core temperature and cerebral damages. ∆S100β displayed a decreasing trend with age, type of operation, shortening of CPB duration, increasing core temperature, lessening severity of cerebral damage and the application of intervenes. Linear correlation analysis revealed that serum S100β concentration at the end of CPB correlated closely with CPB duration. Conclusion: S100 and S100β in cerebrospinal fluid can be more accurate than in the serum for the evaluations of cerebral damage in cardiac surgery. However, cerebrospinal fluid biopsies are limited. But serum S100β and ∆S100β seem to be more sensitive than serum S100 and ∆S100. The cerebral damage in cardiac surgery might be associated with younger age, lower core temperature and longer CPB duration during the operation. Effective intervenes with modified CPB circuit filters or oxygenators and supplemented anesthetic agents or priming components may alleviate the cerebral damage.

Introdution: The transcatheter aortic valve implantation in the treatment of high-risk symptomatic aortic stenosis has increased the number of implants every year. The learning curve for transcatheter aortic valve implantation has improved since the last 12 years, allowing access alternatives. Objective: The aim of this study is to approach the implantation of transcatheter aortic valve through transaortic via associated with off-pump cardiopulmonary bypass surgery in a 67-year-old man, with chronic obstructive pulmonary disease, arterial hypertension and kidney transplant. Methods: Off-pump coronary artery bypass surgery was performed and the valve in the aortic position was released successfully. Results: There were no complications in the intraoperative and postoperative period. Gradient reduction, effective orifice increasing of the prosthesis and absence of valvular regurgitation after implantation were observed by transesophageal echocardiography. Conclusion: Procedural success demonstrates that implantation of transcatheter aortic valve through the ascending aorta associated with coronary artery bypass surgery without CPB is a new option for these patients.

Current technology in robotic surgery allows us to perform myocardial revascularization procedures in a totally endoscopic fashion. We will describe the technique of choice for left internal mammary artery to left anterior descendent artery anastomosis with the use of cardiopulmonary bypass machine. The method is efficient and there is long term follow-up showing similar patency of the graft when compared to conventional methods (when performed through sternotomy).

Complete arterial revascularization for the right coronary artery is underused mainly due to technical issues. Herein we report on a new approach for complete arterial revascularization of arterial revascularization for the right coronary artery branches. Complete arterial revascularization for the right coronary artery revascularization was performed in 8 patients using a reverse T composite arterial graft. None of the patients suffered perioperative myocardial infarction. All patients underwent noninvasive coronary imaging, displaying an early patency rate of 100%. Complete arterial arterial revascularization for the right coronary artery revascularization using a reverse T graft offers a new paradigm with enhanced technical flexibility in performing all arterial myocardial complete revascularizations in selected patients.

An aneurysm of the left ventricle is a complication of acute myocardial infarction. We report a case of a giant aneurysm of the left ventricle after myocardial infarction in a 59 year-old male patient. The surgery to correct the aneurysm was performed with the use of cardiopulmonary bypass under normothermia. A bovine pericardial patch was used for the geometric reconstruction of the ventricular wall affected by the aneurysm. After the procedure, echocardiography and magnetic resonance imaging revealed improvement in left ventricular ejection fraction and volume reduction.

Objective: To apply and to compare the Society of Thoracic Surgery score (STS), EuroSCORE (Eurosc1), EuroSCORE II (Eurosc2) and InsCor (IS) for predicting mortality in patients undergoing to coronary artery bypass graft and/or valve surgery at the Santa Casa Marilia. Methods: The present study is a cohort. It is a prospective, observational, analytical and unicentric. We analyzed 562 consecutive patients coronary artery bypass graft and/or valve surgery, between April 2011 and June 2013 at the Santa Casa Marilia. Mortality was calculated for each patient through the scores STS, Eurosc1, Eurosc2 and IS. The calibration was calculated using the Hosmer Lemeshow test and discrimination by ROC curve. Results: The hospital mortality was 4,6%. The calibration is generally adequate group P=0.345, P=0.765, P=0.272 and P=0.062 for STS, Eurosc1, Eurosc2, and IS respectively. The discriminatory power of STS score 0.649 (95% CI 0.529 to 0.770, P=0.012), Eurosc1 0.706 (95% CI 0.589 to 0.823, P ≤0.001), Eurosc2 was 0.704 (95% CI 0.590-0.818 P=0.001) and InsCor 0.739 (95% CI 0.638 to 0.839, P ≤0.001). Conclusion: We can say that overall, the InsCor was the best model, mainly in the discrimination of the sample. The InsCor showed good accuracy, in addition to being effective and easy to apply, especially by using a smaller number of variables compared to the other models.

Objective: To establish the determinants of the peak VO2 in heart transplant recipients. Methods: Patient's assessment was performed in two consecutive days. In the first day, patients performed the heart rate variability assessment followed by a cardiopulmonary exercise test. In the second day, patients performed a resting echocardiography. Heart transplant recipients were eligible if they were in a stable condition and without any evidence of tissue rejection diagnosed by endomyocardial biopsy. Patients with pacemaker, noncardiovascular functional limitations such as osteoarthritis and chronic obstructive pulmonary disease were excluded from this study. Results: Sixty patients (68% male, 48 years and 64 months following heart transplantation) were assessed. Multivariate analysis selected the following variables: receptor's gender (P=0.001), receptor age (P=0.049), receptor Body Mass Index (P=0.005), heart rate reserve (P <0.0001), left atrium diameter (P=0.016). Multivariate analysis showed r=0.77 and r2=0.6 with P <0.001. Equation: peakVO2=32.851 - 3.708 (receptor gender) - 0.067 (receptor age) - 0.318 (receptor BMI) + 0.145 (heart rate reserve) - 0.111 (left atrium diameter). Conclusion: The determinants of the peak VO2 in heart transplant recipients were: receptor sex, age, Body Mass Index, heart rate reserve and left atrium diameter. Heart rate reserve was the unique variable positively associated with peak VO2. This data suggest the importance of the sympathetic reinnervation in peak VO2 in heart transplant recipients.

Introduction: Acute myocardial infarction is a social health problem of epidemiological relevance, with high levels of morbidity and mortality. Stress is one of the modifiable risk factors that triggers acute myocardial infarction. Stress is a result of a set of physiological reactions, which when exaggerated in intensity or duration can lead to imbalances in one's organism, resulting in vulnerability to diseases. Objective: To identify the presence of stress and its phases in hospitalized and active labor market patients with unstable myocardial infarction and observe its correlation with the life of this population with stress. Methods: The methodology used was a quantitative, descriptive and transversal research approach conducted with a total of 43 patients, who were still active in the labor market, presenting or not morbidities. Data collection occurred on the fourth day of their hospitalization and patients responded to Lipp's Stress Symptom Inventory for adults. Results: Thirty-one patients (72.1%) presented stress and twelve (27.8%) did not. In patients with stress, the identified phases were: alert - one patient (3.2%); resistance -twenty-two patients (71.0%); quasi-exhaustion - six patients (19.4%) and exhaustion - two patients (6.5%). All women researched presented stress. Conclusion: The results suggest a high level of stress, especially in the resistance phase, in the male infarcted population, hospitalized and active in the labor market.

Objective: A retrospective cohort study was preformed aiming to verify the presence of transient dysfunction of gas exchange in the postoperative period of cardiac surgery and determine if this disorder is linked to cardiorespiratory events. Methods: We included 942 consecutive patients undergoing cardiac surgery and cardiac procedures who were referred to the Intensive Care Unit between June 2007 and November 2011. Results: Fifteen patients had acute respiratory distress syndrome (2%), 199 (27.75%) had mild transient dysfunction of gas exchange, 402 (56.1%) had moderate transient dysfunction of gas exchange, and 39 (5.4%) had severe transient dysfunction of gas exchange. Hypertension and cardiogenic shock were associated with the emergence of moderate transient dysfunction of gas exchange postoperatively (P=0.02 and P=0.019, respectively) and were risk factors for this dysfunction (P=0.0023 and P=0.0017, respectively). Diabetes mellitus was also a risk factor for transient dysfunction of gas exchange (P=0.03). Pneumonia was present in 8.9% of cases and correlated with the presence of moderate transient dysfunction of gas exchange (P=0.001). Severe transient dysfunction of gas exchange was associated with patients who had renal replacement therapy (P=0.0005), hemotherapy (P=0.0001), enteral nutrition (P=0.0012), or cardiac arrhythmia (P=0.0451). Conclusion: Preoperative hypertension and cardiogenic shock were associated with the occurrence of postoperative transient dysfunction of gas exchange. The preoperative risk factors included hypertension, cardiogenic shock, and diabetes. Postoperatively, pneumonia, ventilator-associated pneumonia, renal replacement therapy, hemotherapy, and cardiac arrhythmia were associated with the appearance of some degree of transient dysfunction of gas exchange, which was a risk factor for reintubation, pneumonia, ventilator-associated pneumonia, and renal replacement therapy in the postoperative period of cardiac surgery and cardiac procedures.

Introduction: The knowledge of the prevalence of risk factors and comorbidities, as well as the evolution and complications in patients undergoing coronary artery bypass graft allows comparison between institutions and evidence of changes in the profile of patients and postoperative evolution over time. Objective: To profile (risk factors and comorbidities) and clinical outcome (complications) in patients undergoing coronary artery bypass graft in a national institution of great surgical volume. Methods: A retrospective cohort study of patients undergoing coronary artery bypass graft in the hospital Beneficência Portuguesa de São Paulo, from July 2009 to July 2010. Results: We included 3,010 patients, mean age of 62.2 years and 69.9% male. 83.8% of patients were hypertensive, 36.6% diabetic, 44.5% had dyslipidemia, 15.3% were smokers, 65.7% were overweight/obese, 29.3% had a family history of coronary heart disease. The expected mortality calculated by logistic EuroSCORE was 2.7%. The isolated CABG occurred in 89.3% and 11.9% surgery was performed without cardiopulmonary bypass. The most common complication was cardiac arrhythmia (18.7%), especially acute atrial fibrillation (14.3%). Pneumonia occurred in 6.2% of patients, acute renal failure in 4.4%, mediastinites in 2.1%, stroke in 1.8% and AMI in 1.2%. The in-hospital mortality was 5.4% and in isolated coronary artery bypass graft was 3.5%. The average hospital stay was 11 days with a median of eight days (3-244 days). Conclusion: The profile of patients undergoing coronary artery bypass graft surgery in this study is similar to other published studies.

Objective: To analyze a cardiac rehabilitation adapted protocol in physical therapy during the postoperative hospital phase of cardiac surgery in a service of high complexity, in aspects regarded to complications and mortality prevalence and hospitalization days. Methods: This is an observational cross-sectional, retrospective and analytical study performed by investigating 99 patients who underwent cardiac surgery for coronary artery bypass graft, heart valve replacement or a combination of both. Step program adapted for rehabilitation after cardiac surgery was analyzed under the command of the physiotherapy professional team. Results: In average, a patient stays for two days in the Intensive Care Unit and three to four days in the hospital room, totalizing six days of hospitalization. Fatalities occurred in a higher percentage during hospitalization (5.1%) and up to two years period (8.6%) when compared to 30 days after hospital discharge (1.1%). Among the postoperative complications, the hemodynamic (63.4%) and respiratory (42.6%) were the most prevalent. 36-42% of complications occurred between the immediate postoperative period and the second postoperative day. The hospital discharge started from the fifth postoperative day. We can observe that in each following day, the patients are evolving in achieving the Steps, where Step 3 was the most used during the rehabilitation phase I. Conclusion: This evolution program by steps can to guide the physical rehabilitation at the hospital in patients after cardiac surgery.

Introduction: Perioperative myocardial infarction adversely affects the prognosis of patients undergoing coronary artery bypass graft and its diagnosis was hampered by numerous difficulties, because the pathophysiology is different from the traditional instability atherosclerotic and the clinical difficulty to be characterized. Objective: To identify the frequency of perioperative myocardial infarction and its outcome in patients undergoing coronary artery bypass graft. Methods: Retrospective cohort study performed in a tertiary hospital specialized in cardiology, from May 01, 2011 to April 30, 2012, which included all records containing coronary artery bypass graft records. To confirm the diagnosis of perioperative myocardial infarction criteria, the Third Universal Definition of Myocardial Infarction was used. Results: We analyzed 116 cases. Perioperative myocardial infarction was diagnosed in 28 patients (24.1%). Number of grafts and use and cardiopulmonary bypass time were associated with this diagnosis and the mean age was significantly higher in this group. The diagnostic criteria elevated troponin I, which was positive in 99.1% of cases regardless of diagnosis of perioperative myocardial infarction. No significant difference was found between length of hospital stay and intensive care unit in patients with and without this complication, however patients with perioperative myocardial infarction progressed with worse left ventricular function and more death cases. Conclusion: The frequency of perioperative myocardial infarction found in this study was considered high and as a consequence the same observed average higher troponin I, more cases of worsening left ventricular function and death.

Introduction: Complete denervation of transplanted heart exerts protective effect against postoperative atrial fibrillation; various degrees of autonomic denervation appear also after transection of ascending aorta during surgery for aortic aneurysm. Objective: This study aimed to evaluate if the level of cardiac denervation obtained by resection of ascending aorta could exert any effect on postoperative atrial fibrillation incidence. Methods: We retrospectively analysed the clinical records of 67 patients submitted to graft replacement of ascending aorta (group A) and 132 with aortic valve replacement (group B); all episodes of postoperative atrial fibrillation occurred during the 1-month follow-up have been reported. Heart Rate Variability parameters were obtained from a 24-h Holter recording; clinical, echocardiographic and treatment data were also evaluated. Results: Overall, 45% of patients (group A 43%, group B 46%) presented at least one episode of postoperative atrial fibrillation. Older age (but not gender, abnormal glucose tolerance, ejection fraction, left atrial diameter) was correlated with incidence of postoperative atrial fibrillation. Only among a subgroup of patients with aortic transection and signs of greater autonomic derangement (heart rate variability parameters below the median and mean heart rate over the 75th percentile), possibly indicating more profound autonomic denervation, a lower incidence of postoperative atrial fibrillation was observed (22% vs. 54%). Conclusion: Transection of ascending aorta for repair of an aortic aneurysm did not confer any significant protective effect from postoperative atrial fibrillation in comparison to patients with intact ascending aorta. It could be speculated that a limited and heterogeneous cardiac denervation was produced by the intervention, creating an eletrophysiological substrate for the high incidence of postoperative atrial fibrillation observed.

Introduction: In spite of its importance as an experimental model, the information on the great cardiac vein in pigs is sparse. Objective: To determine the morphologic characteristics of the great cardiac vein and its tributaries in pigs. Methods: 120 hearts extracted from pigs destined to the slaughterhouse with stunning method were studied. This descriptive cross-over study evaluated continuous variables with T test and discrete variables with Pearson χ square test. A level of significance P<0.05 was used. The great cardiac vein and its tributaries were perfused with polyester resin (85% Palatal and 15% Styrene) and then subjected to potassium hydroxide infusion to release the subepicardial fat. Calibers were measured, and trajectories and relations with adjacent arterial structures were evaluated. Results: The origin of the great cardiac vein was observed at the heart apex in 91 (76%) hearts. The arterio-venous trigone was present in 117 (97.5%) specimens, corresponding to the open expression in its lower segment and to the closed expression in the upper segment in the majority of the cases (65%). The caliber of the great cardiac vein at the upper segment of the paraconal interventricular sulcus was 3.73±0.79 mm. An anastomosis between the great cardiac vein and the middle cardiac vein was found in 59 (49%) specimens. Conclusion: The morphological and biometric characteristics of the great cardiac vein and its tributaries had not been reported in prior studies, and due to their similitude with those of the human heart, allows us to propose the pig model for procedural and hemodynamic applications.