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Biomedical subjects

O Taşdemir

Publications and source records attributed to O Taşdemir.

At least 19 recordsLinked to original sources
PubMed2002

Inhibition of systemic inflammatory response with sodium nitroprusside in open heart surgery.

BACKGROUND: A nitric oxide donor, sodium nitroprusside has been reported to reduce the inflammatory response during cardiopulmonary bypass (CPB). To investigate this, a double-blind and prospective study was conducted. METHODS: Twenty patients with multi vessel coronary disease were randomly chosen to form study (SNP) and control groups. In the SNP group, 0.5 microg/kg/min sodium nitroprusside were administered for 20 min right after the release of the aortic crossclamp. Mac-1 (CD11b/CD18) leukocyte adhesion molecule expressions, interleukin-6 levels were measured from radial artery blood as well as leukocyte and platelet counts in both groups at 6 different time points: a) before anesthesia, b) after heparin administration, c) after aortic crossclamp release, d) after protamine administration, e) 3 hours after the termination of CPB, f) 24 hours after the termination of CPB. RESULTS: The increase in Mac-1 expressions were not different between the two groups at any time point except the measurements after the administration of protamine. At this time point, Mac-1 expressions were not different between the groups (99.8+/-30.7 vs 134.6+/-95.1%, p=0.076), but higher when compared with the preinduction levels. IL-6 levels for SNP and control groups was 89+/-43 and 215+/-131 pg/dL, respectively (p=0.016) 3 hours after the termination of CPB. Twenty-four hours after the termination of CPB, IL-6 levels were still significantly higher in the control group (47+/-27 vs 111+/-68 pg/dL, p=0.039). Leukocyte and platelet counts were not different at any time point between the groups. CONCLUSIONS: Systemic inflammatory response in patients undergoing CPB can be reduced to a certain level with sodium nitroprusside, especially the activation of vascular endothelial cells can be inhibited, but activation of leukocytes still takes place.

Aged↗
PubMed2001

Long-term patency of sequential and individual saphenous vein coronary bypass grafts.

OBJECTIVES: The long-term patency rates for individual and sequential saphenous vein grafts (SVG) as coronary bypass conduits are angiographically compared; the impact of native coronary vessel characteristics is investigated. METHODS: A total of 875 distal coronary anastomoses on 500 SVGs were assessed in 430 patients at an average of 5.8+/-3 years after a coronary revascularization procedure. RESULTS: The patency rates of sequential conduits were markedly higher than those of individual ones (82 vs. 68%, P=0.0005). Also, the anastomoses on the sequential conduits had better patency (75 vs. 68%, P=0.03). This difference was even more pronounced in coronary arteries of poor quality and small (<1.5 mm) diameter (57 vs. 28% for the sequential grafts and individual grafts, respectively, P=0.001). Also, when the most distally located coronary artery on a sequential graft was of poor run-off, the patency rate for the entire conduit was considerably low (42.5%). CONCLUSIONS: The patency of a sequential vein graft conduit is generally better than that of an individual one, especially for poor run-off coronary vessels, provided that the most distally located anastomosis is done on a good coronary artery in terms of quality and diameter. Using a minimal length of conduits is another advantage. However, failure of a single sequential conduit jeopardizes all the anastomoses along that graft segment. Besides, sequential grafting is technically more demanding, and the technical expertise in performing a sequential anastomosis is probably among the important determinants of short- and long-term patency.

Adult↗
PubMed2001

Approach to sinus of Valsalva aneurysms: a review of 53 cases.

OBJECTIVE: The reported experience with sinus of Valsalva aneurysms (SVAs) is limited. Our approach to this subset of patients and an algorithm-dependent classification are presented. METHODS: Between 1985 and 2000, 53 patients (mean age: 24+/-12; range 4--60) underwent repair for ruptured (64%) or non-ruptured (36%) SVA. Associated lesions were present in 21 patients; VSD in 18, moderate to severe aortic insufficiency in five, aortic stenosis in four (two subaortic membrane and one bicuspid valve), PDA in two, mitral insufficiency in one, tetralogy of Fallot in one and endocarditis in one. Operative procedures included simple or Teflon pledgetted direct suturing (31 cases; 58%), patch repair (21 cases; 40%), and stentless porcine bioprosthetic aortic root replacement in a case with extensive involvement and aortic root distortion (2%). Concomitant procedures were VSD repair in 18 patients, aortic valve replacement in four, aortic valve resuspension in three, subaortic membrane resection in two, PDA ligation in two, mitral annuloplasty in one and total correction in one. RESULTS: Early mortality was 1.9%. A permanent pacemaker was inserted in one patient due to complete heart block. The survivors were followed up for 8.2+/-5 years (range: 21 days to 15 years). There were three reoperations due to suture dehiscence; patch repair was undertaken in these patients with no further unfavorable consequences. All patients were in NYHA Class I or II as of their last follow-up. CONCLUSIONS: Repair of SVA can be performed with an acceptably low operative risk and a good symptom-free long-term outcome expectation. Echocardiography provides all the necessary details for diagnosis. Dual exposure/patch repair strategy is advocated in the ruptured cases.

Adult↗
PubMed2000

Mid-term results of partial left ventriculectomy in end-stage heart disease.

OBJECTIVE: Immediate and mid-term effectiveness of partial left ventriculectomy (PLV) is assessed in 27 idiopathic dilated cardiomyopathy patients. METHODS: All patients were in New York Heart Association (NYHA) class III (17) or IV (ten). The average left ventricular ejection fraction (LVEF) was 19+/-4% by MUGA, and 23+/-4% by digital echocardiography. The mean end-systolic volume (LVESV) was 259+/-66 ml and the mean end-diastolic volume (LVEDV) was 342+/-83 ml. Mitral valve replacement was a routine part of the procedure. RESULTS: Operative mortality was 18.5%, a LVEDP>25 mmHg, left atrial diameter>55 mm, pulmonary artery systolic pressure>40 mmHg, congestive hepatomegaly and NYHA class IV being the mortality predictors. Three-year Kaplan-Meier survival was 64+/-10%, including operative mortality; freedom from congestive heart failure was 65+/-11%. Functional status improved from 3.2+/-0.4 to 1.5+/-0.6 (P=0.0003). The mean LVEF was dramatically increased after PLV (to 40+/-4%, P=0.0001); LVESV was decreased to 90+/-30 ml (P<0.0001) and LVEDV to 160+/-49ml (P<0.0001). This improvement was sustained during the first 30 months. CONCLUSIONS: PLV is a reasonable approach for end-stage patients, providing sustained dramatic changes in ventricular geometry and functional capacity, especially in the absence of compromised right and diastolic left heart functions. Routine replacement of the mitral valve allows a more liberal ventriculectomy and eliminates mitral regurgitation, and this may help minimize ventricular distention.

Activities of Daily Living↗
PubMed2000

Comparison of 21-23 size St. Jude medical valves to the 27-29 size mechanical valves in aortic position. Ten-year follow-up.

BACKGROUND: Between 1986 and 1996, 194 patients underwent isolated aortic valve replacement with 21-23 no. St. Jude Medical mechanical heart valves (small sized group) and 163 patients with 27-29 no. (large sized group). METHODS: The mean age at operation was 45.04+/-15.90 years (range: 12-76 years) for the small sized group and 38.05+/-13.41 years (range: 16-68 years) for the large sized group. Preoperatively, 39.7% of the patients from the small sized group and 42.9% from the large sized group had pure aortic stenosis, 31.9% and 27.6% had pure aortic insufficiency. Most of the patients had rheumatic valve disease. RESULTS: The overall hospital mortality rate was 12.4% and 3.07% respectively in the small sized and large sized groups (p<0.001). The overall actuarial survival rate for 10 years was 95.33+/-2.73% and 93.06+/-3.98% respectively in the small sized group and large sized group (p>0.05). In the small sized group male sex and all complications, in large sized group age and all complications were the statistically important hospital mortality predictors (p<0.05). CONCLUSIONS: Although, operative mortality and long term morbidity were higher in the small sized group, these changes did not reflect the actuarial survivals between the groups. Small sized valves carry some risk, but these risks do not affect long-term survival.

Adolescent↗
PubMed1999

A clinical dilemma: cardiac and pericardiac echinococcosis.

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.

Adolescent↗
PubMed1999

Comparison of reoperation findings of the Carpentier-Edwards (standard) bioprosthesis and the St Jude bioimplant (formerly Liotta) in the mitral position.

Between 1986 and 1996, 50 patients with Carpentier-Edwards porcine bioprostheses and 211 with a St Jude bioprosthesis underwent reoperation because of structural valve deterioration. Structural valve deterioration was defined as an intrinsic abnormality of the prosthesis (leaflet disruption, calcification, leaflet thickening, etc.) that caused stenosis or regurgitation found on physical examination and echocardiography. Fifteen of the Carpentier-Edwards bioprosthesis group were male and 35 were female. Eighty-two of the St Jude group were male and 129 female. The mean age at reoperation was 33.88 +/- 10.31 years (range 19-70) for the Carpentier-Edwards group and 39.03 +/- 9.97 years (range 20-70) for the St Jude group. The average duration was 94.32 +/- 3.83 months for the Carpentier-Edwards group and 73.76 +/- 1.44 months for the St Jude group (P < 0.001). The mean aortic cross-clamp time was 67.4 min (minimum 32, maximum 210) for the St Jude group and 63.21 min (minimum 36, maximum 230) for the Carpentier-Edwards group. Reoperative hospital mortality was 10% (5/50) in the Carpentier-Edwards group and 7.1% (15/211) in the St Jude group (P > 0.05). Late failure modes of the bioprostheses were defined for the purposes of this study as calcification, stenosis and torn leaflets. Of the Carpentier-Edwards group, seven patients (14%) developed calcification, six patients (12%) developed stenosis and 13 patients (26%) developed leaflet tears. Of the St Jude group, the incidences were 22 patients (10%), 67 patients (31.8%) and 87 patients (41%), respectively. This study indicates that the Carpentier-Edwards bioprosthesis is more durable than the St Jude. The St Jude bioprosthesis tended to develop leaflet tears and linear calcification in female patients, and nodular calcification in male patients.

Adult↗
PubMed1999

Carotid disease in patients scheduled for coronary artery bypass: analysis of 678 patients.

The purpose of this article is to investigate the frequency of carotid disease and to identify high-risk groups among patients scheduled for isolated coronary artery bypass grafting (CABG) procedures under nonemergent conditions. A total of 678 consecutive patients underwent preoperative carotid artery duplex scanning (CADS) before CABG procedures. Morphology of carotid artery was determined and five groups were formed. Age, sex, cervical bruit, diabetes mellitus (DM), hypertension, smoking, history of cerebrovascular event (CVE), peripheral vascular disease (PVD), and severity of coronary artery disease were investigated to describe the high-risk group for carotid artery disease. In 41% of patients carotid examination produced normal findings; 46.2% had less than 60% luminal stenoses, 7.1% had 60-79% stenoses, 4.6% had 80-99% stenoses, and 1.2% had total occlusion. Previous cerebral ischemic events (CVE) (p<0.05), hypertension (p < 0.01), smoking (p < 0.01), advanced age (p < 0.01), and female sex (p < 0.01) were identified as high-risk factors for carotid artery stenoses. There was a linear association between carotid disease and coronary disease (p < 0.05). Documentation of previous CVE, hypertension, smoking, advanced age, female sex, and severe coronary artery disease may be helpful in identifying patients at high risk for carotid artery stenoses.

Adult↗
PubMed1999

Coronary sinus retroperfusion during acute experimental coronary artery occlusion.

BACKGROUND: This study was planned to show the effect of retroperfusion and cardiopulmonary bypass on myocardial hemodynamic recovery. METHODS: Eighteen dogs entered this study. After, left anterior descending artery (LAD) was dissected and occluded, the animals were divided into three equal groups; Group I: retrograde coronary sinus perfusion, group II: cardiopulmonary bypass and retrograde coronary sinus perfusion, Group III: control group, left anterior descending artery occlusion only. RESULTS: In Group III, deterioration of the hemodynamic values progressed parallel with the degree of ischemic damage but in Group I, hemodynamic parameters were better because of the retrograde coronary sinus perfusion and minimally affected by the reperfusion. In Group II, at the end of the cardiopulmonary bypass minimal myocardial damage was observed. CONCLUSIONS: There is no statistical difference between Group I and II if we examine the data that was taken after reperfusion although myocardial performance was better in Group II.

Animals↗
PubMed1999

Successful reoperation after Batista partial left ventriculectomy demonstrates patient's hemodynamic recovery.

We report an emergency reoperation due to mechanical valve thrombosis following a Batista partial left ventriculectomy and mitral valve replacement with a St. Jude prosthesis. We re-replaced the valve with an identical St. Jude device and counseled the patient on the importance of routine anticoagulation. To the best of our knowledge, this is the 1st reported case of a patient who has survived cardiac reoperation after a Batista partial left ventriculectomy. Moreover, our report demonstrates that the hemodynamic recovery achieved after a Batista operation can enable a patient to tolerate reoperation on cardiopulmonary bypass, even in the presence of acute pulmonary edema and cardiogenic shock.

Heart Failure↗
PubMed1999

Experimental evaluation of retrograde cerebral perfusion by single photon emission computed tomography technique (SPECT).

BACKGROUND: Protection of the brain is of vital importance during aortic arch aneurysms. In this study efficiency of retrograde cerebral perfusion was evaluated with the use of single photon emission computed tomography technique (SPECT) by using 99mTc hexamethylpropylene amine oxime (HMPAO). METHODS: Four animals were used. The internal maxillary vein was the site of retrograde cerebral perfusion. The animals were studied after the heart rate and respiration were stopped with the use of the high dose drug administration and the brain was perfused with cold Ringer's lactated solution. After this procedure, 99mTc HMPAO-SPECT study was performed. RESULTS: In one animal we did not get any cerebral image because of the competent venous valve in the internal maxillary vein. In the remaining animals, normal brain perfusion was achieved. CONCLUSIONS: 99mTc HMPAO-SPECT study documented that blood flow via the retrograde way meets the metabolic demand of the brain. Retrograde delivery of 99mTc HMPAO did not conclude any poorly perfused area in the brain when in given both sides and all parts of the brain can be effectively perfused by cerebral venous system in hypothermic conditions.

Animals↗
PubMed1999

Is there another type of biventricular atrioventricular connection?

In evaluating a 9-year-old girl, we encountered the following cardiac anomalies: a left atrioventricular valve (the morphologic left atrium on the left side, connected with the morphologic left ventricle); concordant atrioventricular connections; a right atrioventricular valve (a morphologic right atrium on the right side, connected with the morphologic right ventricle); concordant atrioventricular connection; a "central" atrioventricular valve (separating the morphologic right atrium from the morphologic left ventricle); and discordant atrioventricular connection with intact interatrial and interventricular septa. A right-to-left shunt passed through the central valvular structure, which was situated at the atrioventricular septum. This was the only means of mixing pulmonary and systemic blood. We suggest that this case presents a newly recognized cardiac anomaly.

Child↗
PubMed1998

Left ventricular aneurysm repair: an assessment of surgical treatment modalities.

OBJECTIVE: Different closure techniques (linear vs. circular), as well as the efficacy of revascularization in the left ventricular aneurysm repair, with regard to immediate and mid-term results, were assessed and factors having influence on the early mortality and morbidity and survival were analyzed. METHOD: Between January 1991 and November 1996, 248 patients underwent surgical repair for postischemic left ventricular aneurysm. A total of 26 of them were female (10.50%). Linear closure was employed in 121 patients (48.8 %) and circular (patch endoaneurysmorraphy) closure in 127 (51.2%). Coronary revascularization was added in 203 (81.9%) cases. Patients were followed for an average follow-up time of 39.3 months. RESULTS: Early mortality rate was 6% (15 patients). The difference in mortality rate by the repair method was not statistically significant (8.3% in the linear closure group and 3.9% in the circular closure group, P = 0.15). Absence of preoperative angina pectoris (P = 0.029), dyspnea as the presenting symptom, a preoperative left ventricular segmental wall motion scoring of 14 or greater, a cardiopulmonary bypass duration exceeding 2 h (P = 0.004), an aortic clamping time exceeding 1 h (P = 0.026) were associated with early mortality. Concomitant coronary revascularization had no effect on early mortality. However, low cardiac output state was less frequent in patients with concomitant coronary revascularization (P = 0.022). Functional status improved in both groups. Follow-up extending to 81st month revealed no difference in survival between the groups (84% for linear closure group and 92% in circular closure group, including operative mortality, P = 0.12). However, functional status improvement was better in the patients who underwent circular repair (P = 0.0077). Revascularization appeared as having no important influence on both survival and functional status. A preoperative left ventricular segmental wall motion scoring of 14 or greater was associated with a higher incidence of early mortality, low cardiac output syndrome and poor long-term survival. CONCLUSION: Left ventricular aneurysm repair is an important therapeutic intervention and can be performed with reliable results, regardless of repair method, either linear or circular. Long term results revealed better functional status in circular repair group. Concomitant coronary revascularization reduced the incidence of low cardiac output state. Performance of the unaffected regions of myocardium was found to be an important determinant of both early and late outcome.

Adolescent↗