Inhibitory effect of adenosine on intimal hyperplasia and proliferation of smooth muscle cells in a carotid arterial anastomosis animal model.

PURPOSE: The effect of adenosine (9-ß-0-ribifuranosyladenine) on the endothelial cell proliferation and neointimal hyperplasia is investigated in the rabbit carotid artery anastomosis model. METHODS: Twenty-eight New Zealand white rabbits were arranged in four groups of seven animals each. The right carotid arteries of each animal were transsected and re-anastomosed. The left sides remained as control. In Group A, no medication was used. In Group B, subcutaneous Adenosine was applied for 3 days. In Group C, the same dose was applied for 7 days, and in Group D for 21 days. After 28 days, the luminal diameters, luminal areas, intima/media ratios were all measured by using histopathological evaluation. FINDINGS: The mean luminal diameters and areas of the four groups were smaller than the control ones. Massive thickening of smooth muscle cell proliferation and dense intensifying in the connecting tissues were observed most prominently in Group A, in decreasing degrees within other groups. Intima/media ratio was highest in Group A. Scoring the quantity of e-NOS positive staining also revealed a significant difference between the experimental groups and their control associates. CONCLUSION: The process of endothelial cell proliferation and neointimal hyperplasia can be significantly reduced by the use of adenosine.

The effects of PPAR-γ agonist pioglitazone on renal ischemia/reperfusion injury in rats.

BACKGROUND: Acute renal failure due to renal ischemia/reperfusion (IR) injury is a significant clinical problem in cardiovascular surgery. Reactive oxygen species and inflammation play essential roles in the pathophysiology of IR injury. Matrix metalloproteinases (MMPs) are enzymes that play important roles in inflammation and mediate extracellular matrix degradation. It is known that peroxisome proliferator-activated receptor-γ agonists have antiinflammatory and antioxidant effects. In the present study, we aimed to investigate the effects of pioglitazone, a synthetic peroxisome proliferator-activated receptor-γ agonist, on MMPs and oxidative stress in a renal IR injury model in rats. MATERIALS AND METHODS: Male Wistar albino rats were divided into three groups: control (n = 7), placebo (n = 7; saline/p.o.), and pioglitazone (n = 7; 5 mg/kg/day/p.o.). In the control group, a right nephrectomy was conducted without left renal IR injury. In the placebo and pioglitazone groups, pretreatments were started 3 d before operation. In both groups, left renal pedicles were clamped for 60 min and then reperfused for 60 min. Paraffinized renal sections were evaluated histopathologically. Furthermore, expressions of MMP-2, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-2, superoxide dismutase 1 (SOD1), and p47-phox/p67-phox subunits of NADPH oxidase were determined by immunostaining and scoring. RESULTS: In the placebo group, renal IR injury induced diffuse tubular necrosis and intense acute inflammation, but pioglitazone inhibited these effects. MMP-2, MMP-9, and TIMP-2 expression increased in the placebo group. However, while MMP-2 and -9 expression decreased, TIMP-2 expression did not change in the pioglitazone group. p47-phox/p67-phox expression increased in the placebo group, but SOD1 expression did not change. Pioglitazone diminished p47-phox/p67-phox expression, whereas it enhanced SOD1 expression. CONCLUSION: Our results suggest that pioglitazone might be helpful to reduce renal IR injury because of its antiinflammatory and antioxidant effects.

Preoperative mild cognitive dysfunction predicts pulmonary complications after coronary artery bypass graft surgery.

OBJECTIVES: In elderly patients with mild cognitive impairment, noncompliance with respiratory exercises, ineffective expectoration, reluctance in mobilization, and difficulty in learning the use of drugs such as inhalers were observed in the early postoperative period after coronary artery bypass graft surgery. It was hypothesized that respiratory complications may be more frequent in these patients, and so the postoperative respiratory complications in patients with preoperative mild cognitive impairment were compared with the postoperative respiratory complications of a control group. DESIGN: A prospective cohort control. SETTING: A university hospital. PARTICIPANTS: Patients undergoing elective coronary artery bypass graft surgery. INTERVENTIONS: Investigators separated 48 patients>70 years old who were scheduled for elective coronary artery bypass graft surgery into two groups: patients with preoperative mild cognitive impairment (group A, n = 25) and patients with no cognitive impairment (control group; group B, n = 23). The patients' cognitive status was evaluated preoperatively by the Montreal Cognitive Assessment test. MEASUREMENTS AND MAIN RESULTS: Pulmonary functions and respiratory complications were evaluated via chest x-rays and spirometry tests preoperatively and postoperatively. A significant difference was observed between the groups, particularly with regard to atelectasis and prolonged ventilation (p<0.001 and p<0.05). No significant impairment was observed in the spirometry tests of the control group. However, a significant deterioration was observed in the postoperative spirometry tests of patients with preoperative mild cognitive impairment. CONCLUSIONS: This study suggested that mild cognitive impairment was associated with pulmonary complications after coronary artery bypass graft surgery.

Intrapericardial teratoma in a newborn: a case report.

We report a successfully surgically intervened case of intrapericardial teratoma, which was diagnosed prenatally. Intrapericardial teratomas are rare cases, and surgical management of those tumors are challenging in this age group. The compression effect of the mass led to misdiagnosis of the anomaly as a transposition of the great vessels. We conclude that intrauterine echocardiography in experienced hands is an essential tool for the follow-up of these patients to detect the pericardial effusion and compression of the cardiac structures, which may cause tamponade and heart failure.

The effect of resveratrol on intimal hyperplasia and endothelial proliferation of rabbit carotid artery anastomosis.

OBJECTIVES: We assessed the effect of resveratrol on intimal hyperplasia and endothelial proliferation after its use for carotid artery anastomosis in rabbits. METHODS: Fourteen New Zealand-type male rabbits, weighing a mean of 2-3 kg were selected randomly. Their right carotid arteries were transected and anastomosed side by side using 8/0 polypropylene. The rabbits were divided into two groups with seven in each group. While the rabbits in the first group were accepted as the Control group, the rabbits in the second group were given resveratrol (1 mg/kg/day) for 14 days intravenously. At the end of the 28th day, all the carotid artery segments that were transected and anastomosed and the left carotid arteries that did not undergo surgery were removed and evaluated histologically. RESULTS: The results of histological evaluation were as follows: lumen diameter (P <0.001) and lumen area (P <0.05) of the Resveratrol group were larger than those of the Control group, intimal thickness (P <0.05) and media thickness of the Resveratrol group (P = 0.04) were thinner than those of the Control group, and intima/media ratio of the Control group was found to be greater than that of the Resveratrol group (P = 0.002). CONCLUSIONS: Resveratrol can prevent intimal hyperplasia and endothelial proliferation following surgical anastomosis.

Advanced treatment of acute femoropopliteal bypass graft occlusion with Fogarty catheter guidance.

PURPOSE: The guiding role of the Fogarty catheter was investigated among patients suffering from limb ischemia due to acute femoropopliteal bypass graft occlusion. METHODS: A total of 27 patients with a history of femoropopliteal bypass operation who was admitted with acute limb ischemia were enrolled in this retrospective study. In cases in which the Fogarty catheter could not be passed through the popliteal anastomosis, the popliteal region was explored and a new bypass or patch plasty was performed for the distal anastomosis. The cases in which the blood circulation was observed in the graft, but in which the Fogarty catheter balloon was stuck in the native vessels on the proximal and distal side of the graft and the balloon could be withdrawn by deflation, were referred to conventional angiography. The stenosis observed in native vessels was managed by endovascular stent grafting and/or balloon dilatation. FINDINGS: Graft patency was achieved in all patients. In 11 patients, conventional angiography was implemented following embolectomy. In these patients, all the occlusions found as significant on angiography were removed by percutaneous transluminal angioplasty. CONCLUSION: Effective use of Fogarty catheter is safe in acute femoropopliteal bypass graft occlusions and in particular, in the planning of further treatment following thrombectomy.

Bedside surgery to treat patent ductus arteriosus in low-birth-weight premature infants.

BACKGROUND: Patent ductus arteriosus (PDA) is commonly seen in premature infants with low birth weights (LBW). It is a condition that has high mortality and morbidity rates. Early closure of the ductus arteriosus may require surgery or medical treatment. However, the decision of first medical approach for symptomatic PDA closure is still debated. In this study, we compared the surgical and medical treatments for the closure of PDA in premature LBW infants. METHODS: This study included 27 premature infants whose birth weights were lower than 1500 g, who were born in the period between 2011 and 2013 and had symptomatic PDA. Patients were separated into two groups: groups A and B. Group A included patients whose PDAs were closed with medical treatment (n = 16), and group B included patients who had undergone surgical operations for PDA closure (n = 11). RESULTS: There were no statistically significant differences between groups A and B when the groups were compared in terms of birth weight, gestational age, respiratory distress syndrome (RDS), necrotizing enterocolitis (NEC), sepsis, intraventricular hemorrhage (IVH), retinopathy of prematurity (ROP), and pneumothorax. Although the mortality rate was determined to be lower in group B (2 out of 11, 18.1%) than in group A (7 out of 16, 43.7%), no statistically significant difference was found between the two groups. A statistically significant increase was determined in the incidence of kidney function loss in patient group that received Ibuprofen, a medical treatment, in comparison to the patients who had surgery. CONCLUSION: In conclusion, surgery is a safe method to repair PDA in premature LBW infants. Although there is no remarkable difference between surgery and medical treatment, we suggest that a surgical approach may be used as a first choice to repair PDA considering the lower rate of mortality and morbidity and higher rate of closure compared to medical treatment.

Pulsatile versus non-pulsatile flow to reduce cognitive decline after coronary artery bypass surgery: A randomized prospective clinical trial.

BACKGROUND: In this prospective study, we aimed to compare the effect of pulsatile and non-pulsatile flow on the cognitive functions in patients undergoing coronary artery bypass surgery. METHODS: Patients scheduled for their first coronary artery bypass surgery (n = 148) were randomly assigned to the pulsatile flow group (Group A, n = 75) or non-pulsatil group (Group B, n = 73). Cognitive performance was assessed with (MoCA) montreal cognitive assessment test performed by psychologists before coronary artery bypass surgery and 1 month after the operation. RESULTS: Mild cognitive impairment was seen in 12 (16%) patients and serious cognitive impairment was seen in 1 (1.33%) patient in the pulsatile flow group. In the other group, mild cognitive impairment was detected in 23 (31.50%) patients and serious cognitive decline was found in 3 (4.10%) patients. Mean MoCA scores were 25.86 ± 2.62 in group A and 22.12 ± 2.20 in group B. The difference between two groups was statistically significant (P = 0.041). CONCLUSIONS: We suggest that pulsatile flow has beneficial effects to decrease cognitive dysfunction in patients undergoing on-pump coronary artery bypass surgery.

A mandatory modification in extracorporeal biventricular assist device (BIVAD) implantation: intercostal tunnel application: a case report.

In this case, our patient was a heart transplant candidate connected to a respiratory system. An extracorporeal biventricular assist device (BIVAD) was the only option in order to bridge to transplantation. In routine procedures, it is recommended that Berlin Heart Excor cannulas be removed through the subfascial subcostal tunnel. As the severely dilated right ventricle compressed the apex of the left ventricle, which was also dilated to the mid-back zone of the left hemithorax, the whole length of the Extracorporeal BIVAD apical cannula had to remain within the thorax; however, the cannula was removed from the body by creating a tunnel at the 7th intercostal space. In the long-term follow-up, this compulsory modification has proven to be safe and effective.

Effect of tadalafil on neointimal hyperplasia in a rabbit carotid artery anastomosis model.

PURPOSE: Intimal thickening, which results from the response to arterial damage caused by therapeutic interventions or other reasons, is usually called as neointima. Neointimal hyperplasia is a main step in the pathogenesis of late-term restenosis, which is developed after vascular interventions. Reduction in nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling plays a substantial role in the pathogenesis of neointima formation. Phosphodiesterase V is detected in the peripheral coronary and pulmonary vascular smooth muscle cells and in the cardiac tissue. Based on the effects of phosphodiesterase V inhibitors on vascular smooth muscle cells, in the present study, the effect of tadalafil, a new member of phosphodiesterase V inhibitors, on neointimal hyperplasia was investigated in the rabbit carotid artery anastomosis model. MATERIAL AND METHOD: Fourteen male New Zealand white rabbits weighing between 2.5-3 kg, were used. The rabbits were randomly divided into two equal groups; tadalafil group received oral tadalafil (2 mg/kg/day), and PBS group received sterile PBS solution (normal saline; 2 mg/kg/day) for 28 days after the surgery. The right carotid arteries of all rabbits were anastomosed in an end-to-end fashion using 8/0 polypropylene suture. The rabbits were sacrificed at the end of the postoperative period of 28 days. After sacrificing, firstly anastomosis segment on the right carotid artery and secondly a part of the left carotid artery (as control) of each rabbit were removed. Morphometric examination of tissue sections was performed under a light microscope connected to an image capture system. RESULTS: There was a significant difference between the right and left carotid arteries in terms of intimal area and intima/media ratio both in tadalafil and PBS groups (p <0.001 for each). Intimal area and intima/media ratio were increased in the right carotid arteries compared to the left carotid arteries (p <0.001 for each). Besides, when the right carotid arteries of both groups were compared using covariance analysis, it was observed that intimal area and intima/media ratio in the anastomosis site were significantly reduced with tadalafil treatment (p <0.001). CONCLUSION: The present study was promising in terms of tadalafil use as a new agent for the prevention of neointimal hyperplasia, which is the leading cause of late-term graft failure in vascular surgery.

Pulmonary segmental artery ratio: an alternative to the pulmonary artery index in patients with tetralogy of fallot.

The objective of this study was to determine a reliable, alternative ratio to the pulmonary artery (PA) index, which will help to estimate the adequacy of postoperative pulmonary blood flow in patients with tetralogy of Fallot. We propose the pulmonary segmental artery ratio (PSAR), which is an angiographic measure for the quantitative standardization of the total number of pulmonary segmental arteries in a patient. The expected value of the PSAR is 1 and it is constant after the 16(th) week of intrauterine life. Retrospective analysis of the PSAR and PA index calculations in patients with tetralogy of Fallot was conducted. Sixty-one patients were assigned to a moderate or low risk group according to their PSAR; the low risk group included 31 patients whose PSAR was between 0.75-1 (group 1) while the moderate risk group included 30 patients whose PSAR was between 0.50-0.75 (group 2). High risk patients whose PSAR was less than 0.50 were excluded from the study. Postoperative peak right ventricular pressure, the pulmonary artery to systemic pressure ratio, and peripheral arterial oxygen saturation preoperatively after cardiopulmonary bypass were analyzed separately in groups 1 and 2. Postoperative peak right ventricular pressure was lower in group 1 than group 2, while the pulmonary artery to systemic pressure ratio and peripheral arterial oxygen saturation were higher in group 1 than group 2 (P < 0.01). Based on the present findings, it is concluded that PSAR is not as reliable as the Nakata index. However, in cases in which the PSAR and PA index are not correlated, PSAR may be helpful for determining the adequacy of postoperative pulmonary blood flow and postoperative outcomes of patients with hypoplastic pulmonary arteries.