Repositório RCAAP

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Abstract Objective: Deep sternal wound infection following coronary artery bypass grafting is a serious complication associated with significant morbidity and mortality. Despite the substantial impact of deep sternal wound infection, there is a lack of specific risk stratification tools to predict this complication after coronary artery bypass grafting. This study was undertaken to develop a specific prognostic scoring system for the development of deep sternal wound infection that could risk-stratify patients undergoing coronary artery bypass grafting and be applied right after the surgical procedure. Methods: Between March 2007 and August 2016, continuous, prospective surveillance data on deep sternal wound infection and a set of 27 variables of 1500 patients were collected. Using binary logistic regression analysis, we identified independent predictors of deep sternal wound infection. Initially we developed a predictive model in a subset of 500 patients. Dataset was expanded to other 1000 consecutive cases and a final model and risk score were derived. Calibration of the scores was performed using the Hosmer-Lemeshow test. Results: The model had area under Receiver Operating Characteristic (ROC) curve of 0.729 (0.821 for preliminary dataset). Baseline risk score incorporated independent predictors of deep sternal wound infection: obesity (P=0.046; OR 2.58; 95% CI 1.11-6.68), diabetes (P=0.046; OR 2.61; 95% CI 1.12-6.63), smoking (P=0.008; OR 2.10; 95% CI 1.12-4.67), pedicled internal thoracic artery (P=0.012; OR 5.11; 95% CI 1.42-18.40), and on-pump coronary artery bypass grafting (P=0.042; OR 2.20; 95% CI 1.13-5.81). A risk stratification system was, then, developed. Conclusion: This tool effectively predicts deep sternal wound infection risk at our center and may help with risk stratification in relation to public reporting and targeted prevention strategies in patients undergoing coronary artery bypass grafting.

Abstract Objective: Acute kidney injury after cardiac surgery is associated with mortality and morbidity. Therefore, strategies to prevent acute kidney injury are very important. The aim of this placebo-controlled randomized double-blind study was to compare the prophylactic efficacy of N-Acetylcysteine and dopamine administration in patients with pre-existing moderate renal insufficiency who were undergoing cardiopulmonary bypass. Methods: This study included 135 patients with pre-existing moderate renal insufficiency who were scheduled for coronary artery bypass grafting surgery. Serum creatinine and GFR were recorded preoperatively and on the first and second postoperative days. Results: On the first and second postoperative days, the drugs used showed statistically significant differences among the creatinine groups (P<0.001). According to Tukey’s HSD, on the first and second PO, the creatinine of Group N, D and P were significantly different (P<0.001). On the first and second PO, the used drugs showed statistically significant differences among the effects of eGFR (P<0.001). According to Tukey’s HSD on the first postoperative day, the average eGFR score of Group N compared to D and P were significantly difference (P<0.001). On the second postoperative day, the eGFR of Group N and D showed no difference (P=0.37), but P showed a difference (P<0.001). Conclusion: We found that the prophylactic use of intravenous N-Acetylcysteine had a protective effect on renal function, whereas the application of renal dose dopamine did not have a protective effect in patients with pre-existing moderate renal failure.

Abstract Objective: The aim of this study was to describe the demographic, clinical and anatomic characteristics of coronary arteriovenous fistulas in adult patients who underwent open cardiac surgery and to review surgical management and outcomes. Methods: Twenty-one adult patients (12 female, 9 male; mean age: 56.1±7.9 years) who underwent surgical treatment for coronary arteriovenous fistulas were retrospectively included in this study. Coronary angiography, chest X-ray, electrocardiography and transthoracic echocardiography were preoperatively performed in all patients. Demographic and clinical data were also collected. Postoperative courses of all patients were monitored and postoperative complications were noted. Results: A total of 25 coronary arteriovenous fistulas were detected in 21 patients; the fistulas originated mainly from left anterior descending artery (n=9, 42.8%). Four (19.4%) patients had bilateral fistulas originating from both left anterior descending and right coronary artery. The main drainage site of coronary arteriovenous fistulas was the pulmonary artery (n=18, 85.7%). Twelve (57.1%) patients had isolated coronary arteriovenous fistulas and 4 (19.4%), concomitant coronary artery disease. Twenty (95.3%) of all patients were symptomatic. Seventeen patients were operated on with and 4 without cardiopulmonary bypass. There was no mortality. Three patients had postoperative atrial fibrillation. One patient had pericardial effusion causing cardiac tamponade who underwent reoperation. Conclusion: The decision of surgical management should be made on the size and the anatomical location of coronary arteriovenous fistulas and concomitant cardiac comorbidities. Surgical closure with ligation of coronary arteriovenous fistulas can be performed easily with on-pump or off-pump coronary artery bypass grafting, even in asymptomatic patients to prevent fistula related complications with very low risk of mortality and morbidity.

Abstract Objective To evaluate surgical treatment of chronic atrial fibrillation with ultrasound in patients with mitral valve disease, considering preoperative clinical characteristics of patients undergoing surgical procedure and follow-up in the immediate postoperative period, in hospital and up to 60 months after discharge. Methods: We studied 100 patients with chronic atrial fibrillation and mitral valve disease who underwent surgical treatment using ultrasound ablation. Patient data were reviewed by consulting the control reports, including signs and symptoms, underlying disease, functional class, hospital stay, surgical procedure time, ablation time, immediate complications, and complications at discharged and up to 60 months later. Actuarial curve (Kaplan-Meier) was used for the study of permanence without recurrence after 12, 24, 36, 48 and 60 months. Results: 86% of the patients had rheumatic mitral valve disease, 14% had degeneration of the mitral valve, 40% had mitral regurgitation, and 36% had mitral stenosis. Main symptoms included palpitations related to tachycardia by chronic atrial fibrillation (70%), congestive heart failure (70%), and previous episodes of acute pulmonary edema (27%). Early results showed that 94% of the patients undergoing ultrasound ablation reversed the rate of chronic atrial fibrillation, 86% being in sinus rhythm and 8% in atrioventricular block. At hospital discharge, maintenance of sinus rhythm was observed in 86% of patients and there was recurrence of chronic atrial fibrillation in 8% of patients. At follow-up after 60 months, 83.8% of patients maintained the sinus rhythm. Conclusion: Surgical treatment of chronic atrial fibrillation with ultrasound concomitant with mitral valve surgery is feasible and satisfactory, with maintenance of sinus rhythm in most patients (83.8%) after 60 months of follow-up.

Abstract Objective: This study evaluated clinical and diagnostic findings, treatment methods, and follow-up of cases of anomalous coronary arteries from the pulmonary artery. Methods: The study included all cases diagnosed with anomalous coronary arteries from the pulmonary artery between January 2012 and January 2016. Data from patients’ demographic characteristics, electrocardiography, echocardiography, angiographic findings, operation, intensive care unit stay, and follow-up were evaluated. Results: The study included 12 patients (8 male, 4 female), 10 with anomalous left coronary artery from the pulmonary artery (ALCAPA) and 2 with anomalous right coronary artery from the pulmonary artery (ARCAPA). Median age at diagnosis was 4 months (range, 1 month - 10 years old) and median weight was 5.5 kg (range, 3-30 kg). The most common complaints were murmur (n=7) and respiratory distress (n=5). In 4 cases, the initial diagnosis was dilated cardiomyopathy. Electrocardiographs were pathologic in all cases. Echocardiographic examination revealed medium to severe mitral valve regurgitation in 4 cases and reduced (< 40%) ejection fraction in 6 patients. Of the 12 patients, 8 underwent direct implantation of the left coronary artery into the aorta, 2 underwent implantation of the right coronary artery into the aorta, and the remaining 2 underwent a Takeuchi procedure. There were no early mortalities. Median hospital stay was 20 days (range, 5-35 days). Median follow-up duration was 18 months (range, 5-36 months), and no cases required further surgery during follow-up. Conclusions: Anomalous coronary arteries from the pulmonary artery can be successfully repaired providing there is early diagnosis and effective, appropriate intensive care unit follow-up. Therefore, coronary artery origins should be evaluated carefully, especially in cases with dilated cardiomyopathies.

Abstract Objective: This study is designed to evaluate the advantages between peratrial device closure under transesophageal echocardiographic guidance and open heart surgery in atrial septal defect. Methods: From November 2011 to September 2014, 28 patients with atrial septal defect were treated. Fourteen patients received peratrial device closure under transesophageal echocardiographic guidance (TEE group) and 14 patients received cardiopulmonary bypass (CPB group). Clinical parameters during intraoperative and postoperative periods were examined. Results: All patients recovered after surgery without serious complications. Compared with that in CPB group, clinical observations in TEE group showed significant decreases in the operation time (193.6±35.5 vs. 77.4±22.7 min, P<0.05), periods in intensive care unit (31.6±23.3 vs. 17.5±8.1 hours, P<0.05), fluid volume after operation (502.5±439.3 vs. 32.5±7.3 ml, P<0.05), postoperative length of hospital stay (8.9±2.8 vs. 6.8±2.4 days, P<0.05) and total hospitalization cost (7205.9±1617.6 vs. 5882.3±441.2 $, P<0.05). Conclusion: The peratrial device closure of atrial septal defect under transesophageal echocardiographic guidance is a mini-invasive, simple, safe and effective intervention. Its use in the clinical practice should be encouraged.

Abstract Objective: To evaluate our experience following the introduction of a percutaneous program for endovascular treatment of aortic diseases using Perclose Proglide® assessing efficacy, complications and identification of potential risk factors that could predict failure or major access site complications. Methods: A retrospective cohort study during a two-year period was performed. All the patients submitted to totally percutaneous endovascular repair (PEVAR) of aortic diseases and transcatheter aortic valve implantation since we started the total percutaneous approach with the preclosure technique from November 2013 to December 2015 were included in the study. The primary endpoint was major ipsilateral access complication, defined according to PEVAR trial. Results: In a cohort of 123 patients, immediate technical success was obtained in 121 (98.37%) patients, with only two (0.82%) cases in 242 vascular access sites that required intervention immediately after the procedure. Pairwise comparisons revealed increased major access complication among patients with >50% common femoral artery (CFA) calcification vs. none (P=0.004) and > 50% CFA calcification vs. < 50% CFA calcification (P=0.002). Small artery diameter (<6.5 mm) also increased major access complication compared to bigger diameters (> 6.5 mm) (P=0.027). Conclusion: The preclosure technique with two Perclose Proglide® for PEVAR is safe and effective. Complications occur more often in patients with unfavorable access site anatomy and the success rate can be improved with proper patient selection.

Abstract Advent of antiretroviral therapy has increased survival of patients with human immunodeficiency virus (HIV) infections, with the result that some of these patients now develop degenerative diseases, such as atherosclerotic aneurysms. Degenerative thoracoabdominal aortic aneurysm is rare in HIV patients. In this report, a 63-year-old male patient with HIV submitted to open repair of thoracoabdominal aortic aneurysm. The patient did not suffer any type of complication in the perioperative period and remained well in a 28-month follow-up period. In summary, open repair still remains a good alternative for aortic complex aneurysms even in HIV patients.

Abstract The authors report the case of a suicide attempt. A 59-year-old man with self-inflicted penetrating chest trauma underwent emergency cardiothoracic surgery. Pre-operative computed tomography scan showed critical proximity between the blade and the right ventricle. Intraoperative findings showed a pericardial laceration and a huge diaphragmatic lesion with heart and abdominal organs integrity. The diaphragm muscle was repaired with a CorMatrix® patch, an acceptable alternative to the traditional synthetic mesh avoiding infection and repeated herniation.

Abstract Objective: To report the early results of the BYPASS project - the Brazilian registrY of adult Patient undergoing cArdiovaScular Surgery - a national, observational, prospective, and longitudinal follow-up registry, aiming to chart a profile of patients undergoing cardiovascular surgery in Brazil, assessing the data harvested from the initial 1,722 patients. Methods: Data collection involved institutions throughout the whole country, comprising 17 centers in 4 regions: Southeast (8), Northeast (5), South (3), and Center-West (1). The study population consists of patients over 18 years of age, and the types of operations recorded were: coronary artery bypass graft (CABG), mitral valve, aortic valve (either conventional or transcatheter), surgical correction of atrial fibrillation, cardiac transplantation, mechanical circulatory support and congenital heart diseases in adults. Results: 83.1% of patients came from the public health system (SUS), 9.6% from the supplemental (private insurance) healthcare systems; and 7.3% from private (out-of -pocket) clinic. Male patients comprised 66%, 30% were diabetics, 46% had dyslipidemia, 28% previously sustained a myocardial infarction, and 9.4% underwent prior cardiovascular surgery. Patients underwent coronary artery bypass surgery were 54.1% and 31.5% to valve surgery, either isolated or combined. The overall postoperative mortality up to the 7th postoperative day was 4%; for CABG was 2.6%, and for valve operations, 4.4%. Conclusion: This first report outlines the consecution of the Brazilian surgical cardiac database, intended to serve primarily as a tool for providing information for clinical improvement and patient safety and constitute a basis for production of research protocols.

Abstract OBJECTIVE: Risk assessment for operative mortality is mandatory for all cardiac operations. For some operation types such as aortic valve repair, EuroSCORE II overestimates the mortality rate and a new scoring system (German AV score) has been developed for a more accurate assessment of operative risk. In this study, we aimed to validate German Aortic Valve Score in our clinic in patients undergoing isolated aortic valve replacement. METHODS: A total of 35 patients who underwent isolated open aortic valve replacement between 2010 and 2013 were included. Patients with concomitant procedures and transcatheter aortic valve implantation were excluded. Patients' data were collected and analyzed retrospectively. Patients' risk scores EuroSCORE II were calculated online according to criteria described by EuroSCORE taskforce, Aortic Valve Scores were also calculated. RESULTS: The mean age of patients was 61.14±13.25 years (range 29-80 years). The number of female patients was 14 (40%) and body mass index of 25 (71.43%) patients was in range of 22-35. Mean German Aortic Valve Score was 1.05±0.96 (min: 0 max: 4.98) and mean EuroSCORE was 2.30±2.60 (min: 0.62, max: 2.30). The Aortic Valve Score scale showed better discriminative capacity (AUC 0.647, 95% CI 0.439-0.854). The goodness of fit was x2HL=16.63; P=0.436). EuroSCORE II scale had shown less discriminative capacity (AUC 0.397, 95% CI 0.200-0.597). The goodness of fit was good for both scales. The goodness of fit was x2HL=30.10; P=0.610. CONCLUSION: In conclusion, German AV score applies to our population with high predictive accuracy and goodness of fit.

Abstract INTRODUCTION: Elevated hemoglobin A1c levels in patients with diabetes mellitus have been known as a risk factor for acute kidney injury after coronary artery bypass grafting. However, the relationship between hemoglobin A1c levels in non-diabetics and acute kidney injury is under debate. We aimed to investigate the association of preoperative hemoglobin A1c levels with acute kidney injury in non-diabetic patients undergoing isolated coronary artery bypass grafting. METHODS: 202 non-diabetic patients with normal renal function (serum creatinine <1.4 mg/dl) who underwent isolated coronary bypass were analyzed. Hemoglobin A1c level was measured at the baseline examination. Patients were separated into two groups according to preoperative Hemoglobin A1c level. Group 1 consisted of patients with preoperative HbA1c levels of < 5.6% and Group 2 consisted of patients with preoperative HbA1c levels of ≥ 5.6%. Acute kidney injury diagnosis was made by comparing baseline and postoperative serum creatinine to determine the presence of predefined significant change based on the Kidney Disease Improving Global Outcomes (KDIGO) definition. RESULTS: Acute kidney injury occurred in 19 (10.5%) patients after surgery. The incidence of acute kidney injury was 3.6% in Group 1 and 16.7% in Group 2. Elevated baseline hemoglobin A1c level was found to be associated with acute kidney injury (P=0.0001). None of the patients became hemodialysis dependent. The cut off value for acute kidney injury in our group of patients was 5.75%. CONCLUSION: Our findings suggest that, in non-diabetics, elevated preoperative hemoglobin A1c level may be associated with acute kidney injury in patients undergoing coronary artery bypass grafting. Prospective randomized studies in larger groups are needed to confirm these results.

Abstract OBJECTIVE: Myocardial protection is the most important in cardiac surgery. We compared our modified single-dose long-acting lignocaine-based blood cardioplegia with short-acting St Thomas 1 blood cardioplegia in patients undergoing single valve replacement. METHODS: A total of 110 patients who underwent single (aortic or mitral) valve replacement surgery were enrolled. Patients were divided in two groups based on the cardioplegia solution used. In group 1 (56 patients), long-acting lignocaine based-blood cardioplegia solution was administered as a single dose while in group 2 (54 patients), standard St Thomas IB (short-acting blood-based cardioplegia solution) was administered and repeated every 20 minutes. All the patients were compared for preoperative baseline parameters, intraoperative and all the postoperative parameters. RESULTS: We did not find any statistically significant difference in preoperative baseline parameters. Cardiopulmonary bypass time were 73.8±16.5 and 76.4±16.9 minutes (P=0.43) and cross clamp time were 58.9±10.3 and 66.3±11.2 minutes (P=0.23) in group 1 and group 2, respectively. Mean of maximum inotrope score was 6.3±2.52 and 6.1±2.13 (P=0.65) in group 1 and group 2, respectively. We also did not find any statistically significant difference in creatine-phosphokinase-MB (CPK-MB), Troponin-I levels, lactate level and cardiac functions postoperatively. CONCLUSION: This study proves the safety and efficacy of long-acting lignocaine-based single-dose blood cardioplegia compared to the standard short-acting multi-dose blood cardioplegia in patients requiring the single valve replacement. Further studies need to be undertaken to establish this non-inferiority in situations of complex cardiac procedures especially in compromised patients.

Abstract INTRODUCTION: The mortality due to cardiogenic shock complicating acute myocardial infarction (AMI) is high even in patients with early revascularization. Infusion of low dose recombinant human brain natriuretic peptide (rhBNP) at the time of AMI is well tolerated and could improve cardiac function. OBJECTIVE: The objective of this study was to evaluate the hemodynamic effects of rhBNP in AMI patients revascularized by emergency percutaneous coronary intervention (PCI) who developed cardiogenic shock. METHODS: A total of 48 patients with acute ST segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock and whose hemodynamic status was improved following emergency PCI were enrolled. Patients were randomly assigned to rhBNP (n=25) and control (n=23) groups. In addition to standard therapy, study group individuals received rhBNP by continuous infusion at 0.005 µg kg−1 min−1 for 72 hours. RESULTS: Baseline characteristics, medications, and peak of cardiac troponin I (cTnI) were similar between both groups. rhBNP treatment resulted in consistently improved pulmonary capillary wedge pressure (PCWP) compared to the control group. Respectively, 7 and 9 patients died in experimental and control groups. No drug-related serious adverse events occurred in either group. CONCLUSION: When added to standard care in stable patients with cardiogenic shock complicating anterior STEMI, low dose rhBNP improves PCWP and is well tolerated.

Abstract INTRODUCTION: Enhanced respiratory muscle strength in patients with heart failure positively alters the clinical trajectory of heart failure. In an experimental model, respiratory muscle training in rats with heart failure has been shown to improve cardiopulmonary function through mechanisms yet to be entirely elucidated. OBJECTIVE: The present report aimed to evaluate the respiratory muscle training effects in diaphragm citrate synthase activity and hemodynamic function in rats with heart failure. METHODS: Wistar rats were divided into four experimental groups: sedentary sham (Sed-Sham, n=8), trained sham (RMT-Sham, n=8), sedentary heart failure (Sed-HF, n=7) and trained heart failure (RMT-HF, n=7). The animals were submitted to a RMT protocol performed 30 minutes a day, 5 days/week, for 6 weeks. RESULTS: In rats with heart failure, respiratory muscle training decreased pulmonary congestion and right ventricular hypertrophy. Deleterious alterations in left ventricular pressures, as well as left ventricular contractility and relaxation, were assuaged by respiratory muscle training in heart failure rats. Citrate synthase activity, which was significantly reduced in heart failure rats, was preserved by respiratory muscle training. Additionally, a negative correlation was found between citrate synthase and left ventricular end diastolic pressure and positive correlation was found between citrate synthase and left ventricular systolic pressure. CONCLUSION: Respiratory muscle training produces beneficial adaptations in the diaphragmatic musculature, which is linked to improvements in left ventricular hemodynamics and blood pressure in heart failure rats. The RMT-induced improvements in cardiac architecture and the oxidative capacity of the diaphragm may improve the clinical trajectory of patients with heart failure.

Abstract INTRODUCTION: The biggest challenge faced in minimally invasive pediatric cardiac surgery is cannulation for cardiopulmonary bypass. Our technique and experience of cervical cannulation in infants and small children for repair of congenital cardiac defects is reported in this study. METHODS: From January 2013 to June 2015, 37 children (22 males) with mean age of 17.97±8.63 months and weight of 8.06±1.59 kg were operated on for congenital cardiac defects through right lateral thoracotomy. The most common diagnosis was ventricular septal defect (18 patients). In all patients, right common carotid artery, right internal jugular vein and inferior vena cava were cannulated for institution of cardiopulmonary bypass and aorta was cross clamped through right 2nd intercostal space. RESULTS: There were no deaths or any major complications related to cervical cannulation. Common carotid artery cannulation provided adequate arterial inflow while internal jugular vein with inferior vena cava provided adequate venous return in all patients. No patient required conversion to sternotomy or developed vascular, neurological or wound related complications. Three patients had residual lesions (small leak across ventricular septal defect patch-2, Grade II left atrio-ventricular valve regurgitation-1) and one patient had mild left ventricular dysfunction. At discharge, both common carotid artery and internal jugular vein were patent on color Doppler ultrasonography in all patients. In a mean follow-up period of 11.4±2.85 months, all patients were doing well. No patient had any wound related, neurological or vascular complication. No patient had residual leak across ventricular septal defect patch. CONCLUSION: Cervical cannulation of common carotid artery and internal jugular vein is a safe, reliable, efficient and quick method for institution of cardiopulmonary bypass in minimally invasive pediatric cardiac surgery.

Abstract INTRODUCTION: Left atrial ganglionated plexi ablation is an adjuvant technique used to increase the success rate of surgical ablation of atrial fibrillation. Ganglionated plexi ablation requires previous detection. We aimed to assess determinants of successful ganglionated plexi detection and to correlate range of ganglionated plexi ablation with risk of early atrial fibrillation recurrence. METHODS: The study involved 34 consecutive patients referred for surgical coronary revascularization with concomitant atrial fibrillation ablation. Ganglionated plexi detection was done by inducing vagal reflexes in the area of the pulmonary veins and left atrial fat pads. RESULTS: Detection of GP was successful in 85% of the patients. There was no difference in preoperative characteristics nor in atrial fibrillation type between patients in whom ganglionated plexi detection was successful and others. The number of detected ganglionated plexi correlated significantly only with preoperative resting heart rate. Significant negative correlation was found in patients with preoperative heart rate>75 beat/min in terms of total number of detected ganglionated plexi (P=0.04). Average number of detected ganglionated plexi was significantly higher in patients with in-hospital atrial fibrillation recurrence requiring electrical cardioversion (3.8±3) in comparison to rest of the study population (2±1.3; P=0.02). In patients in whom 4 or more ganglionated plexi were detected, significantly increased risk of in-hospital atrial fibrillation recurrence was observed (OR 15; 95% CI 1.5-164; P=0.003). CONCLUSION: Left atrial ganglionated plexi detection was unsuccessful in a considerable percentage of patients. Preoperative heart rate significantly influenced positive ganglionated plexi detection and number of ablated ganglia. Higher number of detected ganglionated plexi was related with early recurrence of atrial fibrillation.

Abstract The endothelium plays an important role in maintaining vascular homeostasis and regulating blood vessel function. Endothelial function is considered an independent predictor for risk of future cardiovascular events in cardiovascular and non-cardiovascular patients, as well as a predictor for postoperative complications in cardiovascular surgery patients. Brachial artery flow-mediated dilation by high-resolution ultrasound is widely used to evaluate endothelium-dependent vasodilation, which is mainly mediated by nitric oxide release. Physical exercise exerts beneficial effects on endothelial function and can be used in both primary and secondary prevention of cardiac and peripheral artery diseases, even in the postoperative period of cardiovascular surgery.

Abstract We present a patient with unstable angina candidate for coronary artery bypass grafting. Saphenous vein graft was used in obtuse marginal and left internal mammary artery to left anterior descending artery properly. After surgery, the patient experienced flaccid paralysis of lower limb and impaired sensation of touch and warmth of knee and below. A computed tomography angiogram of lower limbs and thoracolumbar magnetic resonance imaging showed no abnormality. Based on the symptom, clinical diagnosis of anterior spinal artery syndrome was considered. The artery of Adamkiewicz is an important supplier to the anterior spinal artery. Internal thoracic mammary artery, used in coronary artery bypass grafting, is suspected as a collateral supplier of the artery of Adamkiewicz and has been accused for cause of spinal infarction.