Attenuation of acute lung injury following lower limb ischemia/reperfusion: the pharmacological approach.

AIM: The purpose of this study was to examine the effects of N-acetylcysteine (NAC), calcium dobesilate (DOBE) and aprotinin on the amelioration of lung damage following ischemia/reperfusion injury in a rat hind limb model. A well known antioxidant dimethyl-sulfoxide (DMSO) was also tested for comparison. METHODS: Ischemia was induced in the lower limb for 4 h by vascular clamping and followed by 1 h of reperfusion. Lung injury was evaluated in 5 groups as a saline (control), DMSO, NAC, DOBE and aprotinin group. Plasma creatine kinase, lactate dehydrogenase, thiobarbituric acid reactive substances (TBARS) as well as lung tissue TBARS levels were measured. Lung tissue samples were taken for histological examination. P<0.005 was considered statistically significant. RESULTS: Plasma TBARS values were found to be significantly lower in the DMSO (P<0.005), NAC (P<0.005) and aprotinin (P<0.005) groups compared to the control group. Lung TBARS values were significantly lower in the DMSO, NAC, DOBE and aprotinin groups compared to the control group (P<0.001, P<0.001, P<0.001). Also in the aprotinin group lung TBARS values were found to be significantly lower compared to DMSO (P<0.001), NAC (P<0.001) and DOBE (P<0.001) groups. Histological examination showed less prominent peribronchial leukostasis (P<0.005) and interstitial leukostasis (P<0.005) in all drug groups compared to the control group. CONCLUSION: These observations indicate that DOBE and NAC, which are known to have antioxidant properties and aprotinin, a serine proteinase inhibitor, acted effectively on the prevention of lung injury in a rat hind limb ischemia/reperfusion model. The reason why aprotinin exerts a more protective effect than the other drugs is not clear, however, its clinical use may have the dual advantage of hemostasis and lung protection in surgical practice.

A randomized trial of intravenous iloprost (a stable prostacyclin analogue) versus lumbar sympathectomy in the management of Buerger's disease.

AIM: The aim of this study was to compare the effects of iloprost and lumbar sympathectomy (LS) in the treatment of Buerger's disease. METHODS: Two hundred patients with rest pain and/or ischemic ulcers were randomized to undergo LS or 28-day intravenous treatment of iloprost. The primary endpoint was complete healing without pain or major amputation at 4 and 24 weeks. The secondary endpoints were analgesic requirement, reduction in the ulcer size, 50% reduction of the ulcer, and shift in the modified SVS/ISCVS clinical status grading scale. RESULTS: The comparison was carried out in 162 patients (iloprost: n=84; LS: n=78). Complete healing rate was 61.9% in the iloprost group, but 41% in the LS group at the 4th week (P=0.012); respective values for the 24th week were 85.3%, 52.3%, P<0.001. Analgesic requirement was lower in the iloprost group at the 4th and 24th weeks (P=0.01, and P=0.098, respectively). The size of the ulcers decreased more in the iloprost group than the LS group (P=0.044 and P=0.035 at 4th and 24th weeks); 50% reduction in the ulcer size in the iloprost group was greater than in the LS group (P=0.001 and P=0.009 at 4th and 24th weeks). SVS/ISCVS grading scale demonstrated a better clinical benefit in patients treated with iloprost (P<0.001 at 4th week, and P<0.001 and at 24th week). CONCLUSIONS: The results of this independent study indicate that using iloprost relieves ischemic symptoms better than LS. In the era of stable prostacyclin analogues, there is no reliable evidence to support the use of LS in Buerger's disease.

The effects of clopidogrel and calcium dobesilate on intimal hyperplasia following vascular injury.

BACKGROUND: Neo-intimal hyperplasia is one of the most common causes of failure of arterial patency following cardiovascular interventions. It has been proposed that clopidogrel and calcium dobesilate may play an important role in the amelioration of intimal hyperplasia. The aim of this study is to examine the effect of these agents on intimal hyperplasia occurring after experimental balloon catheter injury. MATERIAL AND METHODS: Twenty-four male New Zealand rabbits were divided into three groups. Endothelial injury was caused by introducing a 2.5 x 20 mm balloon angioplasty-catheter into the left iliac artery. After the procedure, clopidogrel (25 mg/kg/day/orally) or calcium dobesilate (100 mg/kg/day/orally) were given for 2 weeks. Eight rabbits were given a placebo and served as controls. The contralateral non-injured iliac arteries of the control group were considered as normal iliac artery samples. Iliac artery specimens were examined planimetrically and the intima/media ratio was obtained for each vessel. RESULTS: In the control group, the intima/media ratio was still significantly higher (p < 0.05) than the contralateral normal artery 14 days after the balloon catheter injury. In the clopidogrel and calcium dobesilate groups, this ratio had significantly decreased when compared with the control group (p < 0.05). No significant difference was found when the clopidogrel and calcium dobesilate groups were compared. CONCLUSION: The anti-agregant agent clopidogrel, and the venous endothelial regulator calcium dobesilate, ameliorate intimal hyperplasia after experimentally induced vascular injury in rabbit iliac arteries.

Effect of combining phosphodiesterase III inhibitors with St Thomas Hospital's solution used as transplantation preservative solution in isolated rat hearts.

Improved preservation of the harvested heart with attenuation of the reperfusion injury is important for successful outcomes of cardiac transplantations. The most commonly used cardioplegic solution, to prevent ischemic changes has been St Thomas' Hospital cardioplegic solution (STHCS). However, it is neither ideal nor sufficient to prevent myocardial ischemia and reperfusion injury. Phosphodiesterase inhibitors can attenuate the damage due to the injuries of ischemia and reperfusion. In this study we sought to enrich STHCS with a phosphodiesterase inhibitor to improve preservation of cardiac functions. The harvested hearts of 24 rats were divided into four groups. All hearts were mounted on a Langendorff perfusion system. After a stabilization period, cardiac arrest was maintained by STHCS. The hearts were stored in STHCS alone or with milrinone, amrinone, or enoximone for 6 hours. The reperfusion was maintained using a modified Tyrode's solution. All hearts were compared for their preischemic and postischemic left ventricular developed pressure, +dp/dtmax, -dp/dtmax, duration of systole, ejection time, and time to reach peak systolic pressure. Coronary effluent was collected for lactate dehydrogenase (LDH) measurements. The initial values for all metrics were comparable between the groups. During the postreperfusion period, all hearts showed lower peak systolic pressures than the initial values. Although the amrinone group seemed to have higher values, the 25-minute result was at the border of significance and the 30-minute value, significantly higher. All hearts showed far lower results of maximum changes in contractility during the time period (+dp/dtmax) versus the initial values; comparisons between groups were not significant. For the parameter of maximum changes in relaxation during the time period (-dp/dtmax), while other hearts showed lower results, the amrinone group displayed values comparable to the initial ones after 20 minutes. Comparisons between groups were insignificant. While other hearts had comparable values for time of systole, the hearts applied with milrinone reached these values after 15 minutes. Group comparison for time of ejection revealed that the results at 5-minute postreperfusion were higher in the enoximone and the amrinone groups than the milrinone group. Postreperfusion 5-minute results were higher in the enoximone and the amrinone groups than the milrinone group for time to reach peak systolic pressure. LDH levels were lowest in the amrinone group. In conclusion, our study revealed that adding phosphodiesterase inhibitors to STHCS improved peak systolic pressure and maximum changes in relaxation during the time period (-dp/dtmax, mm Hg/s). It also decreased the LDH leakage, which corresponded to the degree of ischemic tissue damage. Amrinone seemed to result in more favorable results, which may be attributed to its additional effects on inflammation, including those on cytokines and leukocyte aggregation.

A brachial aneurysm in childhood caused by Ehlers-Danlos syndrome.

A case of an 11-year-old boy with Ehlers-Danlos syndrome (EDS) type IV is presented. He was referred with a pulsatile mass above the right antecubital fossa and Doppler revealed a saccular aneurysm. Excision and ligation of the brachial artery aneurysm was performed. The diagnosis was confirmed by skin fibroblast cultures and histopathologic evaluation. We conclude that arteriography should be avoided in EDS and color-Doppler should be the sole means of diagnosis. Ligation rather than arterial reconstruction should be preferred.

Cephalic vein and hemodialysis fistula: surgeon's observation versus color Doppler ultrasonographic findings.

The aim of this study was to evaluate whether preoperative color Doppler ultrasonography improves immediate success rates of arteriovenous fistulas for dialysis. One hundred twenty-four patients with chronic renal failure underwent color Doppler ultrasonographic examination of both arms, including the cephalic vein, before arteriovenous fistula construction. Patients were randomly divided into 2 groups: A and B. In group A, there were 52 patients, and the surgeon planned to construct arteriovenous fistulas depending only on physical examination. In group B, which comprised 72 patients, surgeons performed arteriovenous fistula construction on sites labeled by color Doppler ultrasonography. In group A, of 52 patients who had surgery for arteriovenous fistula construction, 13 had fistulas that did not function. Among these 13 patients, 8 were found to have chronic thrombotic changes in the cephalic vein on color Doppler ultrasonography, and 5 had none of these changes. When we checked the color Doppler ultrasonographic findings, we noted that these 5 patients had decreased volume flow in the radial artery. On the whole, the arteriovenous fistulas worked in 39 patients (75%) and did not function in 13 patients (25%). In group B, surgeons followed the color Doppler ultrasonographic results. Of 72 patients who underwent the procedure, 68 patients (94.4%) had functioning fistulas, whereas 4 (5.6%) had fistulas that did not work. These 4 patients were found to have low volume flow in the radial artery. When both groups were compared by chi2 analysis, the difference was statistically significant (P = .002). Group B, in which patients were preoperatively evaluated by color Doppler ultrasonography, had a high success rate. We found that color Doppler ultrasonography is very helpful as a noninvasive procedure for this evaluation. Although many surgical clinics still perform arteriovenous fistula construction without the aid of color Doppler ultrasonographic findings, we think that the use of color Doppler ultrasonography should be emphasized before surgeons proceed with arteriovenous fistula construction.

Right atrial thrombus mimicking myxoma and bilateral pulmonary artery aneurysms in a patient with Behçet's disease--a case report.

A case of Behçet's disease, in which superior vena cava syndrome was the presenting feature is reported. Magnetic resonance imaging and echocardiography revealed a mass lesion in the right atrium. This patient developed bilateral pulmonary artery aneurysms postoperatively and represents one of the bizarre manifestations of Behçet's disease.