Implantation of novel small-diameter polyurethane vascular prostheses interposed in canine femoral and carotid arteries.

OBJECTIVES: The performance of small-diameter (3-5-mm) vascular grafts still poses a challenge in the field of vascular surgery. We present here our preliminary experience with implanting unique small-sized polycarbonate urethane vascular grafts in 7 dogs. MATERIAL AND METHODS: Each animal was implanted with 4 interposition grafts, 2 femoral and 2 carotid. No anti-thrombotic medication was administered. Doppler sonography was performed at 3-month intervals to examine for patency and flow characteristics. Animals were sacrificed electively at 3, 6 and 12 months. RESULTS: At 3 months, all grafts were patent. After 6 months, 3 grafts occluded and at 1 year a further 6 grafts occluded. Hence 9 of 28 grafts occluded (67.9% patency). During the study, no correlation could be established between flow velocity or resistance index and occlusion. Histopathology showed intimal hyperplasia to be the cause of occlusion. CONCLUSIONS: Compared to literature data on small-diameter grafts in the same position, ADIAM's Biomechanical grafts performed clearly better. Compliance data suggest a correlation between elastic compliance and patency.

Mg++SO4 treatment improves the hemodynamics following the acute myocardial ischemia and reperfusion.

BACKGROUND: The effect of Mg++SO4 on myocardial hemodynamics was investigated in this study. METHODS: Twelve dogs were entered in this research. Six dogs received Mg++SO4 and the remaining dogs were considered as controls. The amount of Mg++SO4 that was administered to the animals was 0.15 mmol/kg/hr each. The left anterior descending artery was occluded for a period of 1 hour and the drug was administered during reperfusion. RESULTS: Two hours after reperfusion, cardiac output was 1275+/-50 ml/min in the control group and 1475+/-25 ml/min in the Mg++SO4 group (p<0.05), pulmonary capillary wedge pressure was 18+/-3 mmHg in the control group and 12+/-2 mmHg in the Mg++SO4 group. CONCLUSIONS: In this study it was shown that Mg++SO4 usage after 1 hour arterial occlusion and 2 hours reperfusion protects the heart from the adverse effects of ischemia/reperfusion and had a better central hemodynamics.

Clinical results of the ATS prosthetic valve in 240 implants and review of the literature.

BACKGROUND AND AIM OF THE STUDY: Despite having been used in many thousands of implants, few published data exist concerning the ATS valve. Clinical data from ATS valve implants are presented, and the first two cases of mitral valve thrombosis with the ATS valve reported. Published data are also reviewed comparatively. METHODS: Between September 1998 and July 2000, 240 ATS valve prostheses were implanted in 199 patients, of whom 88 (36.6%) had mitral (MVR), 70 (29.1%) aortic (AVR), and 41 (17.1%) double valve replacements (DVR). Additional procedures were performed in 31 patients (15.6%). Transvalvular gradients and effective orifice areas were measured by transthoracic echocardiography. Total cumulative follow up of all patients was 241.6 patient-years (pt-yr); mean (+/-SE) follow up was 1.25+/-0.51 years. RESULTS: There were six early deaths (3.0%). Overall and event-free survival rates during follow up were 98.96+/-0.73% and 97.90+/-1.22%, respectively. Anticoagulant-related hemorrhage occurred in one patient. The global incidence of hemorrhagic complications was 0.41 per 100 pt-yr. One patient with AVR was reoperated on for periprosthetic leakage in the first postoperative week. Valve thrombosis occurred in two patients with MVR at 12 and 14 months postoperatively. The incidence of valve thrombosis in MVR patients was 1.84 per 100 pt-yr (0.82 per 100 pt-yr overall). Hemolysis was seen only in one patient, echocardiographic examination revealing periprosthetic leakage. CONCLUSION: The short-term outcome in 240 implants showed the ATS valve to be safe, to have a low incidence of complications, and to provide excellent hemodynamic performance.

Evaluation of DNA damage using the comet assay in children on long-term benzathine penicillin for secondary prophylaxis of rheumatic fever.

BACKGROUND: Benzathine penicillin is the most widely used antibiotic in the prophylaxis of children with rheumatic fever. The aim of the present study was to evaluate the DNA damage in children receiving one dose of 1.2 million units benzathine penicillin every 4 weeks over a long period to prevent recurrences of rheumatic fever. METHODS: Thirty-five children with confirmed rheumatic fever under benzathine penicillin prophylaxis were enrolled in the study and 35 healthy children with similar ages and socioeconomic backgrounds served as controls. To detect any DNA damage, the comet assay was performed on circulating lymphocytes from the study subjects. RESULTS: Damaged (limited and extensive migration) cells in children on prophylactic therapy were higher than those in controls (P<0.001). CONCLUSIONS: It has been suggested that differences in the comet scores were induced by the administration of benzathine penicillin over a long period of time and further investigations are needed to confirm this toxic effect.

Sister-chromatid exchange analysis on long-term benzathine penicillin for secondary prophylaxis of rheumatic fever.

A single intra-muscular injection of 1.2 millions units of benzathine penicillin every 4 weeks is the most widely used method for the antibiotic prophylaxis of rheumatic fever. The aim of this study is to evaluate the effect of long-term benzathine penicillin on DNA in patients with rheumatic fever. Thirty children with confirmed rheumatic fever who were on the benzathine penicillin prophylaxis were enrolled in the study, and 30 similar normal children served as a control group. To detect any DNA damage, SCE analysis were performed in circulating lymphocytes of the subjects. A statistically significant increased frequency of SCE was observed in children on the benzathine penicillin prophylaxis (no = 30, mean SCEs/cell +/- SD 7.54 +/- 1.81) as compared to a control group (no = 30, mean SCEs/cell +/- SD 5.82 +/- 1.40). It has been suggested that the difference in the SCE frequencies was induced by the administration of the benzathine penicillin for a long time, and further investigations are needed to confirm this toxic effect.

Two discrete masses of leiomyomatosis in a patient, one extending to the right atrium.

Leiomyomatosis extending to the right side of the heart through the inferior vena cava (IVC) is an extremely rare neoplasm. Although it is pathologically classified as a benign neoplastic formation, its growth and recurrence rate makes its extirpation mandatory. In this case report, we describe a 57-year-old woman who presented with leiomyotosis extending from the IVC to the right atrium (RA). This patient had presented with uterine leiomyoma three years previously. The patient died in the operating theatre from hemostatic problems after surgical complications arising from the unexpected presence of a second tumor.

Hydatid cyst of the abdominal aorta and bilateral common iliac arteries. A case report.

Hydatid disease, a parasitic infestation, is endemic in live-stock raising countries where the custom of feeding offal to dogs prevails. Though infestation of any part of the human body can occur, arterial involvement is a rare affliction. We report here the first case in which abdominal aorta and bilateral iliac arteries were totally occluded with intraluminal cysts.

Primary posterior chest wall echinococcosis.

Hydatid cyst is not mentioned among the chest wall tumours in areas not known to harbour echinococcosis. One of the uncommon sites for echinococcosis even in endemic countries is the chest wall. The striking resemblance between neoplasm and hydatid cysts forms a diagnostic dilemma and makes the correct diagnosis essential before surgery.

Congenital double-orifice mitral valve. A case report.

A three-year-old girl was admitted to Hacettepe Children's Hospital due to sweating and poor feeding. Echocardiography demonstrated ostium primum atrial septal defect with a cleft mitral valve. After two months of medical follow-up with digitalis, she was subjected to open-heart surgery, and a primum-type atrial septal defect with double mitral orifice was found. To avoid creating acute mitral stenosis, the cleft was only partially sutured and the septal defect was closed with a patch. Her postoperative recovery was uneventful. It is emphasized that surgical intervention should be individualized in each case.