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Background: While cardiovascular system and mechanical circulatory support devices are efficiently model the effect of disease and assistance, they can also lend valuable insights into clinical procedures. This study demonstrates the use of a CVS‐VAD model for an invasive procedure; hemodynamic ramp testing, in‐silico. Methods: The CVS model is developed using validated models in literature, using Simscape™. An analytically derived pump model is calibrated for the HeartWare VAD. Dilated cardiomyopathy is used as an illustrative example of heart failure, and heart failure patients are created virtually by calibrating the model with requisite disease parameters obtained from published patient data. A clinically applied ramp study protocol is adopted whereby speed optimization is performed following clinically accepted hemodynamic normalization criteria. Trends in hemodynamic variables in response to pump speed increments are obtained. Optimal speed ranges are obtained for the three virtual patients based on target values of central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), cardiac output (CO), and mean arterial pressure (MAP) for hemodynamic stabilization. Results: Appreciable speed changes in the mild case (300 rpm), slight changes in the moderate case (100 rpm), and no changes in the simulated severe case are possible. Conclusion: The study demonstrates a novel application of cardiovascular modeling using an open‐source acausal model, which can be potentially beneficial for medical education and research. [ABSTRACT FROM AUTHOR]

Objective: To detect and to compare the apoptotic effects of intraoperatively topically applied diltiazem, papaverine, and nitroprusside. Methods: Internal thoracic artery segments of ten patients were obtained during coronary bypass grafting surgery. Each internal thoracic artery segment was divided into four pieces and immersed into four different solutions containing separately saline (Group S), diltiazem (Group D), papaverine (Group P), and nitroprusside (Group N). Each segment was examined with both hematoxylin-eosin and the terminal deoxynucleotidyl transferasemediated dUTP-biotin nick end labeling (TUNEL) method in order to determine and quantify apoptosis. Results: Apoptotic cells were counted in 50 microscopic areas of each segment. No significant difference was observed among the four groups according to hematoxylin-eosin staining. However, the TUNEL method revealed a significant increase in mean apoptotic cells in the diltiazem group when compared with the other three groups (Group S=4.25±1.4; Group D=13.31±2.8; Group N=9.48±2.09; Group P=10.75±2.37). The differences between groups were significant (P=0.0001). No difference was observed between the samples of the diabetic and non-diabetic patients in any of the study groups. Conclusion: The benefit of topically applied vasodilator drugs must outweigh the potential adverse effects. In terms of apoptosis, diltiazem was found to have the most deleterious effects on internal thoracic artery graft segments. Of the analyzed medical agents, nitroprusside was found to have the least apoptotic activity, followed by papaverine. Diabetes did not have significant effect on the occurrence of apoptosis in left internal thoracic artery grafts. [ABSTRACT FROM AUTHOR]

Objective. To study pitavastatin's effects on nuclear factor-kappa B (NF-κB ) and adhesion molecules in human saphenous vein graft endothelial culture indicating its pleotropic properties. Materials and Method. Low-dose (0.1 μM/L) and high-dose (1μM/L) pitavastatin calcium were administered as a frontline therapy in human saphenous endothelial cell culture, followed by induction of inflammation by TNF-α and determination of mRNA level alterations of ICAM-1 and NF-κB genes of endothelial cells using the qRT-PCR method. Additionally, immunofluorescence method was used to show the expression of NF-κB and ICAM-1. Finally, LDH levels were determined by the ELISA method to quantify cytotoxicity. Results. ICAM-1 mRNA expression in the low-dose pitavastatin+TNF-α group was significantly higher than that in the TNF-α group and significantly lower than that in the high-dose pitavastatin+TNF-α group (for all comparisons, P = 0.001). The low-dose pitavastatin+TNF-α group had a similar NF-κB mRNA expression with TNF-α and high-dose pitavastatin+TNF-α groups. Conclusion. Pitavastatin increases ICAM-1 mRNA expression in saphenous vein endothelial cells. Furthermore, the effect of pitavastatin on adhesion molecules appears independent of NF-κB. Novel studies are needed in this field. [ABSTRACT FROM AUTHOR]

Background: Diabetes is a well- identified major risk factor for cardiovascular diseases. This study was performed to evaluate the effect of diabetes and impact of glycemic control on internal thoracic artery (ITA) morphology by electron microscopy. Methods: Thirty patients scheduled for coronary artery bypass grafting were enrolled in this study. Samples of ITA were taken during the surgery for electron microscopic evaluation. Group I (n = 10) consisted of diabetics who have poor glycemic control (HbA1c > 7.5%), group II (n = 10) of well-regulated (HbA1c = 4.4% to 6.2%) diabetic patients, and group III (n = 10) of nondiabetic patients. Samples were prepared as ultrathin sections and an original semiquantitative method of scoring was applied to describe the morphologic changes of endothelium. Final scores were analyzed with analysis of variance and post hoc analysis. Results: In group I large vacuoles, swollen mitochondria were seen in endothelial cells and subendothelial edema was prominent. Endothelia (2.5 ± 1.2), arterial wall (2.0 ± 0.0), and endothelial mitochondria (2.9 ± 1.3) scores of group I were significantly higher than the other 2 groups (p < 0.001). The samples of group II and group III did not show significant differences with each other. The correlation between HbA1c values and total endothelial scores statistically significant (r = 0.912; p < 0.001). Conclusions: There is a correlation between HbA1c values and morphologic changes of ITA graft. Uncontrolled diabetes is an important predictor of morphologic changes evidenced by the ultrastructural findings. These ultrastructural changes were not as prominent in the diabetes mellitus patients with well controlled metabolic statuses and patients without diabetes. [Copyright &y& Elsevier]

Objective: Functional tricuspid regurgitation (FTR) is the most common type of tricuspid insufficiency and occurs approximately in 30% of patients with mitral valve disease. The major etiologic factor in the triggering of right ventricular dilation and thus causing functional tricuspid regurgitation, is pulmonary artery hypertension secondary to mitral valve disease. We aimed to analyze long-term outcomes of patients with mild tricuspid regurgitation at the time of mitral valve replacement. Methods: Sixty-six patients with mild tricuspid insufficiency who underwent mitral valve replacement were included in this observational retrospective study. Mean follow-up time was 8.3±0.7 years. Patients whose tricuspid regurgitation remained unchanged or decreased following operation were enrolled to group 1 (n=32), patients whose tricuspid regurgitation increased were included to group 2 (n=34) and data were compared statistically with t-test, Mann-Whitney U, Chi-square and Fisher Exact test. Multiple regression analysis was performed to determine independent risk factors for FTR progression. Results: Preoperatively female gender (p=0.02), body surface area (p=0.04), left atrium diameter (p=0.01), functional capacity (p=0.03), right ventricle diameter (p=0.04), and left ventricle mass index (p=0.04) were found to be statistically significant between groups. In the follow-up; functional capacity, grade of tricuspid insufficiency, pulmonary artery pressure, vena contracta width (p<0.001), TAPSE (tricuspid annular plane systolic excursion index) (p=0.04), annulus diameter (p=0.02), right ventricle diameter (p=0.01), left ventricle mass index (p=0.05), and ejection fraction (p=0.02) were found to be statistically different between groups. In multiple logistic regression analysis; preoperative LA diameter (OR=5.05; 95% CI:1.49-17.12; p=0.009) and female gender (OR=10.93; 95% CI:1.77-67.31; p=0.01) were found as independent risk factors for FTR progression. Conclusion: This study revealed that mild FTR might advance to moderate to severe grade in more than half of the patients in the follow-up. Thus, surgical approach to even mild FTR should be individualized based on patient's risk assessment. [ABSTRACT FROM AUTHOR]

The article reports a medical case of Buerger disease or Thromboangiitis Obliterans in a young patient which could be a risk factor for heart disease and mentions the symptoms and treatment options for the disease.

Background: Inflammation plays a pivotal role in the pathogenesis of organ dysfunction after cardiopulmonary bypass (CPB). The aim of this study was to investigate whether pentoxifylline (PTX) has effects on the inflammatory process and leukocytes in cardiac surgery patients undergoing CPB. Material and methods: A double-blind, prospective, randomized, placebo-controlled study was undertaken to assess the effect of PTX on leukocyte counts, tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP) levels in 60 patients undergoing CPB for elective coronary artery bypass grafting. In 30 patients, 200 mg of PTX was added to 500 mL NaCl and perfused for 180 min after induction of anaesthesia and also 100 mg of PTX was added to the warm cardioplegic solution; another 30 patients received saline solution as placebo. Results: All measurements were performed before PTX infusion (T0), after induction of anaesthesia (T1), 30 min after weaning from CPB (T2), and 6 hours (T3) and 24 hours postoperatively (T4). PTX did not change the percentage of eosinophils, basophils, neutrophils, monocytes, or lymphocytes, or CRP levels. In the control group, however, total leukocyte count and IL-6 level at T3 and T4 period were significantly higher than the study group. The progressive increment in TNF-α level observed at each period was also significantly prominent in the control group. Conclusion: CPB-related whole body inflammatory response could be partially inhibited by intraoperative PTX administration. This effect of PTX would be helpful in preventing the well-known complications of CPB-induced systemic inflammation. [ABSTRACT FROM AUTHOR]

Background: Four methods of radial artery harvesting were evaluated with transmission electron microscopy and tissue lipid peroxidation to determine the degree of damage to the artery.Methods: Radial artery samples from 4 groups of patients (10 samples from each group) who underwent coronary artery surgery were evaluated. In groups I and II, radial arteries were stored in a solution containing 100 mL patients'' own heparinized oxygenated blood and 5 mg nitroglycerine. The grafts were distended in group II. In groups III and IV, side branches of the grafts were occluded and left in situ until the coronary anastomosis. In group III, the distal end of the graft was also occluded, while in group IV, both ends were open.Results: The least degree of endothelial damage and disruption of arterial wall integrity were in group IV according to electron microscopic evaluation. The grafts in group III were relatively in good condition compared to groups I and II. Tissue lipid peroxidation was also lowest in group IV. Tissue lipid peroxide levels correlated with ischemic preservation period of the radial artery (r = 0.426). Total semiquantitative transmission electron microscopic scores of the radial artery samples correlated with the lipid peroxide levels (r = 0.581) and ischemia times (r = 0.734).Conclusions: All arterial grafts, including the radial artery that will be used for coronary artery surgery should not be left ischemic during harvesting to prevent endothelial damage. Ischemia of the conduits for coronary artery grafting can be prevented by leaving them in their anatomic position until the distal coronary artery anastomosis. [Copyright &y& Elsevier]

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Multivessel spontaneous coronary artery dissection (SCAD) is extremely rare, and to the best of our knowledge, triple-vessel dissection has been reported in only 7 patients to date. We present the successful surgical treatment of the triple coronary artery dissection in a 57-year-old man. The patient had aortic valve replacement simultaneously. Triple SCAD is a rare and life-threatening condition, and long-term results are necessary for an optimum treatment approach. It should be kept in mind that triple SCAD may be more common and fatal than thought, as uninvestigated cases of sudden death could mask the true incidence and prognosis of triple SCAD. [Copyright &y& Elsevier]

Cerebral venous thrombosis in various clinical conditions, such as congenital heart disease (CHD) and hypercoagulable states, have been recognized previously. However, dural sinus thrombosis in a pediatric patient with Antiphospholipid Syndrome (APLS) after the repair of a ventricular septal defect (VSD) has not been reported yet. A child who underwent an operation for the surgical repair of VSD under cardiopulmonary bypass (CPB) developed a stroke after the procedure. A cranial computer tomography (CT) scan of the patient showed dural sinus thrombosis and severe cerebral edema. APLS and CPB were thought to be the only risk factors of dural sinus thrombosis. This observation warrants attention and screening should be taken into consideration in patients with APLS who carry a higher risk for dural sinus thrombosis after CPB. [ABSTRACT FROM AUTHOR]

Competing Interests: Conflict of Interest: The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Objectives: A continuous-flow centrifugal blood pump system has been recently developed as an implantable left ventricular assist device for patients with endstage heart failure. The objective of this study was to evaluate the initial in vivo performance of a newly developed left ventricular assist device (iHeart or Istanbul heart; Manufacturing and Automation Research Center, Koc University, Istanbul, Turkey) in an acute setting using a pig model., Materials and Methods: Three pigs (77, 83, 92 kg) received implants via a median sternotomy, with animals supported for up to 6 hours. An outflow cannula was anastomosed to the ascending aorta. Anticoagulation was applied by intravenous heparin administration. During the support period, pump performance was evaluated under several flow and operating conditions. All pigs were humanely sacrificied after the experiments, and organs were examined macroscopically and histopathologically., Results: Flow rate ranged between 1.5 and 3.6 L/min with pump speeds of 1500 to 2800 revolutions/min and motor current of 0.6 to 1.3 A. Initial findings confirmed thatthe iHeart ventricular assist device had sufficient hydraulic performance to support the circulation. During the experimental period, plasma free hemoglobin levels were found to be within normalranges.Thrombus formation was not observed inside the pump in all experiments., Conclusions: The iHeart ventricular assist device demonstrated encouraging hemodynamic performance and good biocompatibility in the pig model for use as an implantable left ventricular assist device. Further acute in vivo studies will evaluate the short-term pump performance prior to chronic studies for long-term evaluation.

Deep venous thrombosis is frequently seen in lower extremities. However, when seen in the iliac level, mass effect of an underlying pathology must be considered. In this report, we present two cases with upper region deep venous thrombosis, which had underlying pathologies of appendicitis and non-Hodgkin lymphoma.

Purpose: We aimed to present our preliminary single-center experience of the endovascular management of thoracic and abdominal aortic ruptures., Materials and Methods: Between September 2010 and May 2012, 11 consecutive patients (nine males, two females; age range, 26-80 years) with thoracic and abdominal aortic ruptures underwent endovascular repair in our unit. Thoracoabdominal computed tomography (CT) angiography was performed for diagnosis and follow-up. Patients were selected for endovascular repair by a cardiovascular surgeon, anesthesiologist, and interventional radiologist. All repairs were performed using commercially available stent-grafts. The patients were followed up with CT angiography before discharge, at six months, and yearly thereafter., Results: Three patients died by day 30. One patient died due to an unsuccessful procedure and hemodynamic instability; two patients died because of comorbidities. The other eight patients were followed for six to 24 months after the procedure. No endoleaks or late ruptures were observed during the follow-up period. The patient with iatrogenic thoracic aortic rupture developed paraplegia after the procedure., Conclusion: Reduced mortality due to aortic rupture has been reported with the expanding use of endovascular repair. Reports of small centers are important because of the rarity of these pathologies, and because transferring patients with aortic rupture to a referral center is not usually possible.

The electrocardiographic changes early after uncomplicated coronary artery bypass with complete revascularization were examined preoperatively and on the 1st and 3rd postoperative days in 53 patients. Heart rate, PR index, corrected PR interval, corrected P dispersion, corrected duration of QRS complex, corrected QT dispersion, corrected QT interval, rhythm, QRS axis, ST-segment changes, and blocks were determined. Changes in new parameters obtained by different combinations of R, S, and T waves were also studied. On the 1st postoperative day, atrial fibrillation was significantly less prevalent, right bundle branch block increased significantly, and QRS axis was significantly more positive but returned to baseline on the 3rd postoperative day. Postoperative heart rate and PR index were significantly higher than preoperative values. In the postoperative period, corrected PR interval was significantly lower, corrected QRS complex duration was significantly shorter, corrected QT interval was significantly longer, and corrected QT dispersion showed a significant increase on the 1st postoperative day. This study defines electrocardiographic changes in uncomplicated patients with complete revascularization. Any deviations from these findings may alert us to the need for further evaluation of an undesired event.

The feasibility of using modified Allen tests to evaluate arterial circulation in the forearm for possible radial artery grafting, and the correlation of these tests with Doppler ultrasonography, were examined. The hand circulation of 50 patients scheduled for coronary artery bypass grafting was assessed by plethysmography, pulse oximetry, and pencil Doppler, as well as Doppler ultrasonography. Flow, velocity, and diameter of the radial, ulnar, and snuffbox arteries were recorded, and radiological screening indices were evaluated to establish a standard set of criteria. The results of modified Allen tests by plethysmography and pulse oximetry demonstrated the dominance of the ulnar artery. The indices of flow x diameter and velocity x diameter, obtained from Doppler ultrasound measurements, confirmed the dominance of the ulnar artery. When compression was applied to the arteries sequentially, significant alterations were found. The arterial circulation in the forearm can be safely evaluated by the modified Allen tests with plethysmography, pulse oximetry, and pencil Doppler, as these results correlated with Doppler ultrasound.

Cardiac injury, occurred after traumatic brain injury (TBI), has been recognized for more than a century. Bcl-2 is a key regulatory component of the mitochondrial cell death pathway, and its overexpression is cytoprotective in many cell types. The therapeutic agents, which induce the expression of bcl-2 protein, might provide a new therapy to prevent cardiac myocyte damage following TBI. In this study, we investigated whether methylprednisolone sodium succinate (MPSS) influences the expression of bcl-2 in the heart. Wistar-Albino female rats underwent TBI (300 g/cm) generated by the weight-drop method, and were left untreated (n = 6) or treated with either MPSS (30 mg/kg) (n = 6) or vehicle (albumin solution) (n = 6). The heart was isolated from each animal with TBI. For comparison, the hearts were isolated from sham-operated (n = 6) and control rats (n = 6). The relative expression of bcl-2 mRNA in the heart was quantitated by real-time polymerase chain reaction. We also assessed lipid peroxidation in the heart tissue by determining the concentration of thiobarbituric acid-reactive substances (TBARs) as an indicator of tissue damage. The bcl-2 expression level was significantly higher in the hearts of MPSS-treated rats compared to that of other TBI groups (p < 0.0001). Moreover, TBI increased the lipid peroxidation in the heart, which was significantly reduced by the treatment with MPSS (p < 0.0001). These findings provide evidence for the efficacy of MPSS in protection of cardiac myocytes to achieve optimal heart donation after TBI in heart transplantation.

Background: Inflammation plays a pivotal role in the pathogenesis of organ dysfunction after cardiopulmonary bypass (CPB). The aim of this study was to investigate whether pentoxifylline (PTX) has effects on the inflammatory process and leukocytes in cardiac surgery patients undergoing CPB., Material and Methods: A double-blind, prospective, randomized, placebo-controlled study was undertaken to assess the effect of PTX on leukocyte counts, tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and C-reactive protein (CRP) levels in 60 patients undergoing CPB for elective coronary artery bypass grafting. In 30 patients, 200 mg of PTX was added to 500 mL NaCl and perfused for 180 min after induction of anaesthesia and also 100 mg of PTX was added to the warm cardioplegic solution; another 30 patients received saline solution as placebo., Results: All measurements were performed before PTX infusion (T0), after induction of anaesthesia (T1), 30 min after weaning from CPB (T2), and 6 hours (T3) and 24 hours postoperatively (T4). PTX did not change the percentage of eosinophils, basophils, neutrophils, monocytes, or lymphocytes, or CRP levels. In the control group, however, total leukocyte count and IL-6 level at T3 and T4 period were significantly higher than the study group. The progressive increment in TNF-alpha level observed at each period was also significantly prominent in the control group., Conclusion: CPB-related whole body inflammatory response could be partially inhibited by intraoperative PTX administration. This effect of PTX would be helpful in preventing the well-known complications of CPB-induced systemic inflammation.