Erdem Silistreli

Surgical Management of Giant Aneurysms Complicating Arteriovenous Fistulae

The creation of an arteriovenous fistula (AVF) is frequently used to achieve easier access for haemodialysis in patients with chronic renal insufficiency. The most frequent late complication of AVFs is aneurysm formation, which carries the risk of spontaneous rupture. This study reports on 18 patients with giant aneurysms that developed on antebrachial AVFs who were operated on over a period of 6 years. Colour duplex ultrasonographic examination of the upper extremity was performed in all but one patient in the preoperative period. Surgical management included resection of the aneurysm and re-establishment of arterial continuity. There were no complications such as infection, ischaemic extremity loss, neurological sequelae or mortality. Colour duplex ultrasonographic examinations after 6 months were all normal. The mean follow-up period was 29.1 months (range 7 − 50 months). There were no additional vascular complications observed during follow-up. Early surgical intervention is the recommended treatment of choice for giant aneurysm complicating antebrachial AVF.

A case of a bronchogenic cyst in a rare location

Bronchogenic cysts occur as a result of a developmental fault during the division and budding of the tracheobronchial tree in the embryonic period. They are usually located in the mediastinum and intrapulmonary regions. They may cause serious respiratory distress in childhood; they present less commonly in adults and often present with a variety of symptoms, including recurrent infections. We report the case of an adult female patient who presented with recurrent pulmonary infections and swelling of the neck because of a bronchogenic cyst that was unusually located in the cervical region.

Early protective effects of iloprost, a stable prostacyclin analog, during spinal cord ischemia in a rabbit model

Spinal cord ischemia may develop into paraplegia in some cases during operation of the thoracoabdominal aorta. This is attributable to the vulnerability of spinal motor neurons to ischemia. In this study, iloprost was used as an agent to decrease the severity of ischemia and reperfusion injury to the spinal cord motor neurons. Twenty-one rabbits were randomized into three groups of seven animals each: group A (iloprost not administered), group B (25 ng/kg per minute iloprost), and group S (sham-operated). The spinal cord ischemia model was created by a 15-min occlusion of the aorta just caudal to the renal artery with a balloon catheter. Administration of iloprost began 10 min before occlusion of the aorta, and continued thereafter for 60 min. The pre- and postocclusion arterial pressure and heart rate recordings, results of blood gas analyses, and hematocrit and glucose levels were recorded. The spinal cords were removed after 8-h monitoring of neurologic function. Viable and nonviable motor neurons in the anterior horn of the spinal cord were counted under light microscopy. Any significant alteration in hemodynamics, blood gases, and other physiologic parameters could not be detected within the groups. Iloprost had a moderately hypotensive effect. Neurologic function in terms of Johnson scoring was significantly better in the iloprost group (P < 0.05). The number of viable cells was higher, whereas the number of nonviable cells was lower in iloprost group, when compared with the control group (P < 0.05). Higher numbers of viable motor neurons were consistent with the neurological findings. As a result of this study we concluded that iloprost infused during clamping of the aorta mitigates the spinal cord injury due to ischemia and reperfusion, and has a significant protective effect.

Stroke and Myxoma

Cardiac myxoma was detected by transthoracic echocardiography in 8 patients (aged 11 to 64 years) who were admitted between 1991 and 1999 with stroke or transient ischemic attacks, representing 80% of the total myxoma cases treated in this period. All patients underwent surgery and the myxomas were successfully removed. There were no recurrences during a mean follow-up of 3.1 years. In the presence of unexplained transient ischemic attack, cerebral infarction, or syncope, this relatively rare cardiac lesion should be suspected and investigated by transthoracic echocardiography.

Insulin—Blood Cardioplegia Decreases Matrix Metalloproteinase Activity in Ischaemia-reperfusion Injury during Coronary Artery Bypass Surgery

Reperfusion of myocardium during coronary bypass activates matrix metalloproteinases (MMPs) with changes occurring in the levels of tissue inhibitors of metalloproteinases (TIMPs) in the myocardium. This study investigated the effects of insulin-blood cardioplegia on MMP activity and TIMP levels during reperfusion. Non-diabetic patients undergoing coronary artery bypass graft with cardiopulmonary bypass were randomized into a control group (n = 12) or an insulin group (n = 12). Blood cardioplegia was used for both groups; insulin and glucose were added to the insulin group. Blood samples were obtained from the coronary sinus just before aortic cross clamping and after 1 and 30 min of reperfusion. Plasma proenzyme MMPs (proMMP-2 and −9) and TIMPs (TIMP-1 and TIMP-2) levels were measured. There were no differences between groups for MMP-2 and TIMP-2 levels. However, insulin diminished proMMP-9 activation, although some still occurred. TIMP-1 consumption lessened during reperfusion which, we conclude, was as a result of the diminished MMP activation. This is the first open heart surgery study in which diminished MMP activation was achieved via a metabolic change.

A new minimally invasive method of aortofemoral revascularization.

In recent years, minimal invasive surgical applications have been used in every field of surgery and became a routine application for some kinds of operations. Mini-laparotomy has been limited to abdominal incisions between 3 and 10 cm long. Four aortobifemoral and one aortofemoral bypass cases that were performed with mini-laparotomy incision between January 1997 and February 1998 are presented. In all cases, revascularization of lower extremities was performed successfully without enlarging the incision. The average operation time was shorter and the number of transfused blood units was significantly lower in that group when compared to the conventional laparotomy group of 12 cases. In all cases, bowel sounds appeared in 2 to 8 hours and at the end of 24 hours, oral nutrition was started. The mean discharge time from the hospital was 4.7 days. With the advantages of less operation time, optimal aortic exposure, ability in safe cross-clamping, less postoperative pain, less scar tissue occurrence, early resumption of intestinal functions, early mobilization and shorter hospitalization time, the mini-laparotomy technique is a safe reliable method for use in aortobifemoral bypass operations.

Effects on the Endocrine System of Pulsatile and Nonpulsatile Perfusion in Heart Surgery

The effects of cardiopulmonary bypass on the endocrine system were investigated in 10 patients who had pulsatile perfusion and in another 10 who had nonpulsatile perfusion during coronary bypass or valve replacement surgery. Measurements were made of thyroid-stimulating hormone, free and total triiodothyronine, free and total tetraiodothyronine, adrenocorticotropic hormone, cortisol, aldosterone, growth hormone, insulin, and glucose at 5 fixed time intervals up to 24 hours postoperatively. In the perfusion period, free and total triiodothyronine levels were less depressed in the pulsatile group. The mean level of growth hormone was significantly higher in the pulsatile group after 60 minutes of perfusion. The mean levels of insulin and glucose were significantly lower in the pulsatile group after 60 minutes of perfusion. Other changes were not statistically significant. We concluded that pulsatile perfusion was of benefit in stabilizing glucose and some hormone levels.

Transthoracic Colour Doppler Ultrasonography in the Evaluation of Internal Thoracic Artery Bypass Graft Patency

The internal thoracic artery (ITA) is the most important conduit for coronary artery bypass grafting. The quality of the anastomosis joining the ITA to the left anterior descending coronary artery has a major impact on left ventricular perfusion. The rapid detection of flow disturbances due to sub-optimal anastomosis is, therefore, of great prognostic significance. In this study, 47 coronary bypass patients were examined using colour Doppler ultrasonography peri-operatively and 4–6 months post-operatively. Findings were correlated with clinical observations and a treadmill exercise test. The pre-operative ITA flow pattern was normally triphasic, but changed post-operatively to simulate the normal biphasic flow pattern of left anterior descending coronary artery. A 35-case-control group was used to compare pre-operative ITA flow characteristics. The authors conclude that Doppler parameters, clinical findings and the treadmill test can be used in combination for the routine evaluation of graft patency, and to select cases that require more invasive coronary angiography.

Lung-Volume Reduction in Parallel with Coronary Heart Surgery: A Case Report

For patients with severe disabling emphysema, lung-volume reduction surgery has recently been introduced as an alternative to transplantation. Performing parenchyma resection from appropriate areas can improve pulmonary functions in selected patients having severe emphysema with a flattened diaphragm. We report the case of a patient, who urgently needed coronary revascularization and was otherwise inoperable because of severe chronic obstructive pulmonary disease (COPD). We carried out lung-volume reduction surgery at the same time as the coronary bypass.

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.