Sahin Bozok

The clinical utility of vascular mapping with Doppler ultrasound prior to arteriovenous fistula construction for hemodialysis access

Purpose To compare the outcomes of vascular access (VA) procedures performed using physical examination (PE) alone to PE and ultrasound vein mapping for assessment of patients needing hemodialysis access. Methods Comparative analysis of data obtained by retrospective review of records of 63 patients who underwent PE and vascular mapping (VM) using colored Doppler ultrasonography (CDUS) and 76 patients assessed by physical examination alone to schedule vascular access surgery. The parameters assessed to study the impact of these two different pre-operative assessment approaches included selection of surgical site, procedure, construction of arteriovenous fistulas (AVF) and grafts (AVG), negative surgical exploration rates and surgical outcomes (maturation and patency rates). Results The rate of successfully constructed AVF increased significantly from 75% to 97% (P=.001) with pre-operative ultrasonographic vascular mapping. In 22 patients (34.9%) the access planned with physical examination was modified based on CDUS examination. In 12 patients, the surgical site for AVF creation and type of surgical procedure were modified based on the CDUS results. Permanent access placement rates were significantly higher in patients assessed with CDUS (P=.001). All patients who underwent vascular mapping had successful VA construction while the PE group had a 18.4% negative surgical exploration rate. When fistulas were assessed at six months, the patency rate was 80.7% for the physical examination (PE) group and 93.4% for the vascular mapping (VM) group. Conclusions Pre-operative vascular mapping using CDUS significantly increases the success of AVF construction and patency.

Surgical stimulation of angiogenesis

Objective The results of surgical approaches are unsatisfactory in patients with a distal arterial bed that is ineligible for revascularization. In this retrospective study, we investigated outcomes in patients who underwent surgical interventions that are reported to induce angiogenesis. Method 6 patients diagnosed with thromboangiitis obliterans were included in this study. Of these 6 patients, 2 underwent femoropopliteal bypass surgery using reversed great saphenous vein as a conduit. The other 4 underwent ascending venous arterialization (bypass from the popliteal artery to the great saphenous vein at the level of medial malleolus, using reversed great saphenous vein). Results During the early postoperative period, all of the reversed saphenous vein grafts were occluded. The mean postoperative ankle-brachial index increased from 0.33 to 0.83. During the postoperative period, intermittent claudication disappeared in all patients. Angiograms taken during the postoperative period showed evidence of neovascularization when compared to those taken during preoperative evaluation. Conclusion Wound healing is an inflammatory process that simultaneously activates angiogenesis. We propose that the improved ankle-brachial index values and neovascularization shown in our patients were associated with this inflammatory process.

The effect of combined hyperbaric oxygen and iloprost treatment on the prevention of spinal cord ischaemia–reperfusion injury: an experimental study

OBJECTIVES Hyperbaric oxygen (HBO) has been shown to be effective in preventing neurological injuries in animal models of ischaemia, whereas iloprost (IL) prevents ischaemia-related mitochondrial dysfunction and reduces infarction size after focal cerebral ischaemia in animal models. The aim of the present study was to investigate the effect of combined HBO and IL treatment on spinal cord ischaemia-reperfusion (IR) injury by neurological, histopathological and biochemical methods in an experimental study. METHODS Eighty New Zealand white male rabbits were randomly allocated into one of five study groups. The HBO group received a single session of HBO treatment and the IL group received an infusion of 25 ng/kg/min IL; the HBO + IL group received both HBO and IL and the control group received only 0.9% saline; the fifth group was the sham group. Levels of S100β protein, neuron-specific enolase (NSE) and nitric oxide (NO) were measured at onset, at the end of ischaemia period and at the 24th and 48th hour of reperfusion. Physical activity was assessed using Tarlov criteria 24, and the spinal cords of the sacrificed rabbits were evaluated histopathologically. Additionally, tissue malondialdehyde (MDA) and antioxidant enzyme activities [total superoxide dismutase (SOD); catalase (CAT) and glutathione peroxidase (GSH-Px) were assessed. RESULTS Neurological scores in the HBO, IL and HBO + IL groups were statistically significantly better compared with the control group at the 24th (P = 0.001 for all) and 48th hour (P = 0.001 for all). Histopathological scores in the HBO, IL and HBO + IL groups were also significantly better compared with the control group (P = 0.003, 0.001 and 0.001, respectively). Whereas MDA, NSE, S100β protein and NO concentrations were significantly lower, CAT and GSH-PX levels were significantly higher in either sham or treatment groups compared with the control group. CONCLUSIONS Since we demonstrated beneficial effects on spinal cord IR injury, we think that both HBO and IL, either alone or in combination, may be reasonable in the treatment of IR injury. Furthermore, there did not appear to be synergistic effects with combined treatment. More research is needed for practical application in humans, following thoracoabdominal aortic surgery.

Surgical Treatment of Postinfarction Left Ventricular Pseudoaneurysms

OBJECTIVE Left ventricular pseudoaneurysm is a rare but serious complication of acute myocardial infarction. It is under debate whether surgical intervention is mandatory in asymptomatic patients. The aim of this report was to present our experience based on surgical treatment and midterm outcomes of patients with postinfarction left ventricular pseudoaneurysm. METHODS Eight consecutive patients who underwent left ventricular pseudoaneurysm operation between January 1, 1995, and January 1, 2006, were included in the study. There were 5 male and 3 female patients. Mean age was 62.87 +/- 5.03 years. All patients had echocardiography and coronary angiography before the operation. Two anterior and 6 posterior pseudoaneurysms were detected. Left ventricular pseudoaneurysm was repaired with a synthetic patch by the remodeling ventriculoplasty method of Dor in all patients. Coronary revascularization was performed if necessary. Preoperative, operative, and postoperative data were collected from the patient cohorts. RESULTS The mean duration from myocardial infarction to diagnosis of the ventricular septal rupture was 13.5 +/- 12 days. Additional coronary artery bypass surgery was performed with a median of 1.2 grafts in 5 patients (62.5%). The mean postoperative mechanic ventilator support time was 20.12 +/- 29.22 hours. Overall 30-day mortality was 12.5% with 1 patient death. The mean intensive care unit stay was 3.75 +/- 2.1 days. The late mortality rate was 12.5%. In the follow-up period (mean, 30.66 +/- 16.86 months), of the 6 patients who were alive, 5 were in New York Heart Association class I or II and 1 was in class III because of pre-existing low left ventricular ejection fraction. Transthoracic echocardiography showed good left ventricular configurations without a false aneurysm together with increases in the ejection fractions. CONCLUSION Prompt diagnosis and early surgical intervention is essential for patients with large or expanding left ventricular pseudoaneurysms due to the high propensity of fatal rupture. Associated coronary artery bypass grafting may reduce early mortality of patients with left ventricular pseudoaneurysm by resuscitating the ischemic myocardium.

Bilateral pseudoaneurysm secondary to intraarterial tianeptine abuse.

Mycotic aneurysms occur due to destruction of the vessel wall, either by infection of a previously healthy artery wall, or through secondary infection of a preexisting aneurysm. Although mycotic aneurysms are frequent in femoral artery, mycotic pseudoaneurysms of femoral artery are rare (1, 2). Tianeptine is a tricyclic antidepressant with a unique mechanism of action as a glutamatergic modulator. However, tianeptine is also known for its abuse and dependence potential (3-5). We hereby report a case with bilateral femoral pseudoaneurysm due to intraarterial administration of tianeptine in a patient with drug addiction, and surgical treatment of this type of pseudoaneurysm.

α-tocopherol and ascorbic acid in early postoperative period of cardiopulmonary bypass

Aim To investigate whether &agr;-tocopherol and ascorbic acid have effect on the suppression of inflammation in the early postoperative period after open heart surgery. Methods A total of 59 patients who had undergone cardiopulmonary bypass (CPB) in the Cardiovascular Surgery Department of a tertiary center between June 2008 and December 2008 were retrospectively investigated. The study group consisted of 34 patients (25 men, 9 women) to whom ascorbic acid (500 mg/day) and &agr;-tocopherol (300 mg/day) were administered on the day of operation (0th day) and the first four consecutive postoperative days. In contrast, 25 controls (20 men, 5 women) received no additional anti-inflammatory medications. The two groups were compared in terms of demographics, blood parameters such as C-reactive protein (CRP) and white blood cell (WBC) count, and durations of cross-clamp and CPB. Results In the control group, CRP levels were found to be increased on the first postoperative day (P < 0.001) and CRP levels were correlated with triglyceride levels on the day of operation (P = 0.009) and the first postoperative day (P = 0.021). On the second postoperative day WBC count was found to be decreased (P = 0.008) and correlated with glucose level (P < 0.005). In the study group, CRP levels were found to be inversely correlated with serum high-density lipoprotein (HDL) (P = 0.049) on the first postoperative day and directly correlated with triglyceride levels on the second postoperative day (P = 0.017). Blood glucose levels were found to be increased on the first postoperative day (P = 0.021) and a correlation was detected between WBC count on the fourth postoperative day and doses of ascorbic acid and &agr;-tocopherol (P = 0.027). Conclusion Suppression of the systemic inflammatory response to CPB is a double-edged sword and whether this suppression aids in the attenuation of morbidity and mortality is obscure. In this respect, ascorbic acid and &agr;-tocopherol seem to display some anti-inflammatory effect, but further studies are necessary to reveal the actual therapeutic potential and the complex mechanism related to biochemical and inflammatory parameters.

Dextroposition of the aorta in tetralogy of Fallot

Criticisms of Dr Anderson have given theimpression that we might not be able to elucidateourhypothesisverywell,whichsuggestedanaorticdextroposition ranging between 5% and 95%. Ourrelevant presentation ‘‘Dextroposition of aorta intetralogy of Fallot’’, which was submitted at the2008 ‘‘World Congress of the World Society ofCardio-Thoracic Surgeons organised in Kos island,Greece’’, and our investigation ‘‘Think twice whileinserting a transannular patch’’ published in 2009

Approach to the vascular complications of lumbar disc surgery

The objective of this study was to demonstrate the role of major surgery on patients presenting with vascular complications after lumbar disc surgery. A retrospective analysis of seven cases treated surgically in two tertiary care centers between August 2001 and June 2010 was carried out. The average age of patients (three women and four men) was 35.8 ± 7.2. The most common vessel injured was the left common iliac artery occurring in five patients (71.4%), followed by the left common iliac vein injury detected in two patients (28.5%). Transperitoneal approach was preferred in all cases and primary suturing, graft interposition and end-to-end anastomoses were the surgical methods used for the repair of vascular injury. No mortality was seen in our series during the follow-up period of two years; however, the most noteworthy complication was paraplegia occurring in one patient. Vascular injury occurring at lumbar discus surgery has a considerable potential for morbidity and mortality. A high index of suspicion is necessary for early diagnosis. In hemodynamically instable patients, the transperitoneal approach provides better exposure and more effective control of hemorrhage, while minimal angiography and endovascular intervention should be preserved for hemodynamically stable cases.

Aortic coaptation in repair.

Thanks to the authors for their article, which teaches us many things [1]. Because the reoperation rate is 10% in the long-term results, we searched and came to the conclusion that, in remodelling and subvalvular annuloplasty, the durability of leaflets worsens due to the inability of aortic expansion [2]; for this reason, the durability of the leaflets should be enhanced. In the supracoronary graft + annuloplasty method, the expansion property of the aorta is lost [2] and so the flow becomes turbulent due to the expandable ring. This situation begets aneurysm, dissection and leaflet destruction in the graft-free part. The expandable ring causes turbulent flow. The shape and angular difference in time causes an increase in the turbulent flow. There are two factors influencing aortic leaflet coaptation:

Aortic valve replacement in true severe aortic stenosis with low gradient and low ejection fraction.

OBJECTIVE The results of aortic valve replacement are uncertain among patients with severe aortic stenosis, reduced left ventricular ejection fraction, and low mean transvalvular gradient. The aim of the present study was to report on 27 patients who underwent surgery for aortic stenosis with left ventricular ejection fraction <or=30% and mean transvalvular gradient <30 mmHg. METHODS The study was performed between January 2000 and December 2005. Twenty-seven patients with aortic stenosis with a calculated valve area <1.0 cm2, aortic mean transvalvular gradient <30 mmHg, and ejection fraction <or=30% were studied. Exclusion criteria were coronary artery disease, concomitant valvular operation, previous aortic valve replacement, or more than moderate aortic valve regurgitation. Preoperative clinical, echocardiography and dobutamine echocardiography, cardiac catheterization and coronary angiography, and operative data were recorded in all patients. Patients who were diagnosed with true aortic stenosis were divided into 2 groups according to left ventricular ejection fraction changes during dobutamine echocardiography, 16 with recruitable myocardium (group 1) versus 11 without (group 2). RESULTS One patient from group 2 died. The functional capacities of all of the patients in group 1 significantly improved in the postoperative period (P = .001). All of the patients except for 1 in group 1 had improved left ventricular ejection fraction after the operation (P <.001). The comparison of the preoperative and postoperative functional status of these patients in group 2 was also statistically significant (P = .001). The 10 of the 11 patients in group 2 who were alive had left ventricular ejection fraction value changes that were not significant statistically (P = .096). The comparison of the improvement of functional capacities of the groups revealed a significant difference; that is, the improvement was higher in group 1 (P = .039). CONCLUSION Left ventricular ejection fraction and functional capacity improved after aortic valve replacement in patients with left ventricular dysfunction, low mean transvalvular gradient, and aortic valve replacement in these patients has acceptable mortality rates with significantly improved functional status.