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Featured researches published by Birol Yamak.
The Annals of Thoracic Surgery | 1999
C Levent Birincioğlu; Haşmet Bardakçi; Şeref Küçüker; Ahmet Tulga Ulus; Kemal Arda; Birol Yamak; Oğuz Taşdemir
BACKGROUND Cardiac and pericardial echinococcosis as a life-threatening disease may present with a clear picture most of the time, however it may also become a clinical puzzle. METHODS In the period between 1977 and 1998, 14 patients were operated on with the diagnosis of cardiac and pericardial echinococcosis. Nine patients were operated on with standard cardiopulmonary bypass (CPB) techniques, and the remaining 5 patients were operated on without CPB. Transesophageal echocardiography (TEE) or intraoperative surface echocardiography were used to plan and perform the operation for the late cases. RESULTS One patient died during the postoperative period due to the rupture of interventricular septum. All other patients survived the perioperative period, received mebendazole treatment, and exhibited no recurrence during the follow-up. CONCLUSIONS The definitive treatment is the surgical extraction of the cyst. Because the clinical picture may vary according to the number, size, and location of cysts, as well as complications, cardiac echinococcosis should be remembered and included in the differential diagnosis to achieve the treatment. Intraoperative surface echocardiography is of paramount value for diagnosis and planning the management of a successful surgery.
The Journal of Thoracic and Cardiovascular Surgery | 1996
Oğuz Taşdemir; Ugursay Kiziltepe; Haldun Y. Karagoz; Birol Yamak; Sule Korkmaz; Kemal Bayazit
UNLABELLED One hundred twenty patients who had diffuse atherosclerotic lesions necessitating reconstruction of the left anterior descending artery with or without open endarterectomy and coronary artery bypass grafting were investigated retrospectively and compared with 130 patients who underwent conventional bypass grafting in the same time frame. METHODS Sixty-one endarterectomies were performed with long arteriotomies (group I) and 59 patch reconstructions were placed over stenosing plaques without an endarterectomy (group II). Patients having only conventional coronary bypass constituted group III. RESULTS Hospital mortalities were 6.5%, 5.1%, and 1.5% in group I, group II, and group III, respectively (p = not significant). Five patients in group I (8.1%), six in group II (10.1%), and two in group III (1.5%) had perioperative myocardial infarction (group II vs group III, p = 0.016). Angiographic restudy of grafts to the left anterior descending system revealed a patency rate of 81.5% in group I, 79.1% in group II, and 94.4% in group III patients after mean periods of 6.3, 5.7, and 6.1 years, respectively (p = not significant). Actuarial survivals at 7 years were 94% +/- 5.0%, 74.8% +/- 16%, and 90.9% +/- 7.4% in groups I, II, and III, respectively (group I vs group II, p = 0.007; group II vs group III, p = 0.008). Freedom from recurrent angina at 7 years was 42.7% +/- 15.6% in group I, 33.5% +/- 19% in group II, and 71.9% +/- 14.2% in group III (group I vs group III, p = 0.03; group II vs group III, p = 0.0001). Thirty-four percent of patients in group I, 24% in group II, and 60.4% in group III were working actively in the late postoperative period (p = 0.0001). CONCLUSION Extended revascularizations of the left anterior descending coronary artery increase surgical risk, although not to a statistically significant degree, and should be performed only of necessity. However, once needed, revascularization is a lifesaving procedure with acceptable early and long-term results.
The Annals of Thoracic Surgery | 1999
Cemal Levent Birincioğlu; Seref Alp Kucuker; Elif G Yapar; Ülkü Yildiz; Ahmet Tulga Ulus; Birol Yamak; Salih Fehmi Katircioglu; Oğuz Taşdemir
BACKGROUND Rheumatic mitral valve stenosis is still an endemic disease in some parts of the world and may complicate pregnancy and perinatal period. During the 10-year period between January 1988 and December 1997, 10 pregnant women with mitral stenosis were operated on. METHODS Combined cesarean delivery and closed mitral valvulotomy (CMV) were performed on 6 patients, combined cesarean delivery and Mitral Valve Replacement (MVR) were performed on 1 patient, and 3 patients had CMV during their third trimester. RESULTS There was 1 stillbirth. All other patients and delivered babies were healthy. MVR was necessary for mitral restenosis in one patient 5 years after her CMV. Three of the remaining patients had some degree of restenosis but did not require reoperation. CONCLUSION CMV when indicated during pregnancy can be performed with low risk. For symptomatic patients responding to medical therapy, a combined approach of cesarean section and CMV will prevent possible complications that may arise on perinatal period due to hemodynamic fluctuation.
Journal of Cardiac Surgery | 1999
S. Fehmi Katircioglu; A. Tulga Ulus; Birol Yamak; lbrahim Ozsoyler; Levent Birincioglu; Oguz Tagdemir
Abstract From 1986 to 1996, 2585 patients underwent valve replacement with the St. Jude medical prosthesis. Sixty experienced mechanical valve thrombosis. Seventeen of 60 patients (28.3%) had isolated aortic valve replacements, 33 had isolated mitral valve replacements (55%), and 10 had double valve replacements (16.7%) (aortic and mitral valve replacement). All patients who underwent reoperation for mechanical valve thrombosis were functional Class III or IV. Against medical advice, systemic anticoagulation with warfarin sodium had been discontinued or used only intermittently. Thus, anticoagulant activity was not adequate. The diagnosis of thrombosis was made by clinical examination, laboratory findings, and echocardiography and cineradiography. Of the 60 patients, 9 patients died early after surgery or before discharge. Most of the deaths were attributed to low cardiac output. The overall hospital mortality was 15%. The overall 10‐year actuarial survival rate was 82.8 ± 1.6%. In our study, reoperation for thrombosed mechanical prosthesis was not an independent parameter determining mortality. Age was the only statistically important hospital mortality predictor. Of this group, 90% suffered mechanical valve obstruction within the first 5 years after operation. These results suggest that valve re‐replacement appears to be a suitable surgical treatment for thrombosis of mechanical prosthetic valves, especially in the young. In these patients subsequent anticoagulation management is necessary.
Angiology | 1999
S. Fehmi Katircioglu; Tulga Ulus; Birol Yamak; Zülfikar Saritas; Ülkü Yildiz
Twelve animals (26 ± 5 kg) were subjected to the study. In this experimental study, the authors used prostacyclin to inhibit the toxic metabolite release during protamine admin istration. Animals were divided into two equal groups. Six animals received prostacyclin (the prostacyclin group), and the other six animals did not receive any additional treatment (the control group). All cardiac output and biochemical measurements were evaluated at baseline; before cardiopulmonary bypass; and at 5, 30, and 60 minutes after protamine administration. The measured cardiac index showed that the hearts treated with prostacyclin had satis factory preservation of left ventricular function. Metabolic and biochemical data showed that the tumor necrosis factor level was raised significantly in the control group (20.75 ± 2.2 in the control group and 13.75 ± 2.5 pg/mL in the prostacyclin group). Also, E and P selectin levels were elevated in the control group, but this change was less marked in the prostacyclin group. In addition, the intracellular adhesion molecule-1 (ICAM-1) level was significantly higher in the control group than in the prostacyclin group (9.26 ±2.13 in the control group and 5.13 ± 1.66 ng/mL in the prostacyclin group). The authors observed that prostacyclin inhibited the toxic mediator release during heparin reversal with protamine. This inhibition is one way of protecting the myocardium reserves from protamine cardiotoxicity.
Prostaglandins & Other Lipid Mediators | 1998
S. Fehmi Katircioglu; Zülfikar Saritas; A. Tulga Ulus; Birol Yamak; Doğan Yücel; Selime Ayaz
A total of 12 mongrel dogs were divided into two equal groups. Six animals received IIoprost and the other 6 animals did not receive any additional treatment. In the Iloprost group, Iloprost was added to the cardioplegic solution (25 ng). Also, Iloprost was used (10 ng/kg/min.) 5 min. before and after cross-clamping. All cardiac output and biochemical measurements were evaluated before cross-clamp and 15 min., 1 h, and 4 h after cross-clamp. The measured dp/dt shows that the hearts treated with Iloprost preserved left ventricular function. Comparison of contractility indices between the groups revealed that contractile recovery was 59% in the control group and 71% in the Iloprost group (p < 0.05). Tumor necrosis factor (TNF) alpha level was significantly elevated in the control group (p < 0.001). Its level was 22.2 +/- 2.2 pg/mL in the control group and 13.8 +/- 1.0 pg/mL in the Iloprost group. E- and P-selectin levels were elevated in the control group (p < 0.001). ICAM-1 level was also elevated in the control group. ICAM-1 level was 17.7 +/- 1.8 ng/mL in the control group and 8.5 +/- 1.8 ng/mL in the Iloprost group. The Iloprost that was added to the cardioplegic solution and low dose administration during the pre- and post-ischemic period inhibits the toxic mediator release from endothelium-leukocyte interaction and reduces the severity of ischemia-reperfusion injury.
European Surgical Research | 1998
Ulus At; Zafer H. Iscan; Zülfikar Saritas; Can C; Birol Yamak; Katircioglu Sf; Murat Bayazit
Purpose: The aim of this study was to evaluate the efficacy of octreotide in modulating the progression of intimal hyperplasia in autogenous vein bypass grafts in a canine model. The effect of the drug on the progression of intimal hyperplasia was measured with the Gilman parameter, a measure used extensively as a wound-healing descriptor. Methods: 12 mongrel dogs were randomly and equally divided into two groups. The first group (octreotide group) was administered octreotide 20 µg/kg/day. The control group (group II) received saline solution by subcutaneous injection. Each dog had 8- to 10-cm segments of autogenous jugular vein bypassed to the femoral arteries. Quantitative data on luminel narrowing over time from intimal hyperplasia were compared from calculated Gilman parameters after image analysis of retrieved, histologically processed graft sections. Each vein graft was analyzed by computerized morphometric analysis. Results: The mean Gilman parameter for distal graft segments was 0.47 ± 0.17 mm in the control group and 0.25 ± 0.07 mm in the octreotide group 6 weeks after operation (p < 0.05). Distal graft segments between the control and octreotide groups were statistically significant. In proximal, medial and distal graft segments, the mean Gilman parameters were 0.51 ± 0.16 mm in the control group and 0.37 ± 0.18 mm in the octreotide group, the difference being statistically significant (p < 0.01). Conclusion: Octreotide significantly inhibits myointimal thickening, and these data support the efficacy of octreotide in reducing intimal hyperplasia in arterialized vein grafts during the short postoperative period. Further investigations are required to as certain whether this beneficial effect of octretide persists in the long term.
Asian Cardiovascular and Thoracic Annals | 1999
C Levent Birincioğlu; A. Tulga Ulus; S. Fehmi Katircioglu; Birol Yamak; Arzum Kale; Gülden Aydog; Oğuz Taşdemir
A unique case of right atrial myxoma originating from the septal leaflet of the tricuspid valve is described. The tumor was detected by echocardiography and resected along with part of the septal leaflet, followed by primary repair.
Asian Cardiovascular and Thoracic Annals | 1998
Birol Yamak; Binali Mavitaş; Ahmet Saritas; S. Fehmi Katircioglu; A. Tulga Ulus; Levent Birincioglu; Y.Haldun Karagöz; Erol Sener; Oğuz Taşdemir; Kemal Bayazit
The Liotta porcine bioprosthesis is a third generation bioprosthesis with a very low profile supraannular configuration with low-pressure glutaraldehyde-fixed tissue. Between May 1986 and December 1990, 670 patients underwent isolated mitral valve replacement with Liotta porcine bioprosthesis. There were 403 (60%) females and 267 (40%) males; the mean age was 39.03 ± 4.57 years (range, 16 to 75 years). The predominant lesion was combined mitral stenosis and mitral insufficiency in 46% of the patients. The operative mortality rate was 5.9% and the most frequent cause of the mortality was low cardiac output. Total follow-up was 3193.5 patient-years. The average follow-up period was 6.1 ± 2.5 years (range, 1 to 10 years). During the late period, 44 patients (1.4% per patient-year) died. The long-term survival estimate at 10 years was 84.8% ± 2.7%. Structural valve deterioration developed in 198 patients (6.2% per patient-year). Actuarial estimates of freedom from structural valve deterioration at 5 and 10 years were 87.6% ± 1.5% and 28.5% ± 4.5% and it was unrelated to sex or age. Most patients (88%) who developed bioprosthesis dysfunction underwent repeat valve replacement. The period between the implantation and development of structural valve deterioration was 5.9 ± 1.8 years for female patients and 6.2 ± 1.8 years for males (no statistically significant difference). We concluded from the early and high rates of structural valve deterioration in this young age group that the Liotta porcine bioprosthesis has limited long-term durability for mitral valve replacement.
Asian Cardiovascular and Thoracic Annals | 2000
Birol Yamak; Mustafa Emir; Tulga Ulus; Ayşen Aksöyek; Zafer H. Iscan; S. Fehmi Katircioglu; Oğuz Taşdemir
From 1986 to 1995, 513 young women of childbearing age (11 to 45 years) underwent mitral valve replacement with a bileaflet St. Jude Medical prosthesis. Twenty-one patients became pregnant within 3 years postoperatively. The mean age of these patients at the onset of pregnancy was 27 ± 8 years (range, 16 to 43 years). Follow-up was complete for all pregnant patients. Of 11 who continued to take warfarin during pregnancy, one had a premature delivery, 2 had spontaneous abortions, and 8 had therapeutic abortions. Five patients who ceased oral anticoagulant therapy had normal deliveries but 4 underwent reoperation for valve thrombosis postnatally, with concurrent left hemiplegia in one case. The other 5 patients adhered to an anticoagulation protocol for pregnancy; there were 3 normal deliveries, 1 premature birth, and 1 abortion. There is a high risk of thromboembolism in patients with mechanical heart valves whose anticoagulants are interrupted during pregnancy. We believe that careful supervision can reduce maternal morbidity and mortality.