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O Tasdemir

Publications and source records attributed to O Tasdemir.

At least 19 recordsLinked to original sources
PubMed2003

Coronary reoperations without the use of cardiopulmonary bypass.

BACKGROUND: Reoperations of coronary artery surgery still carry a higher mortality and morbidity rate, compared to primary revascularization procedures. Coronary artery bypass reoperations without the use of cardiopulmonary bypass (CPB) is a potential strategy that has been developed to decrease mortality and morbidity. MATERIALS AND METHODS: Between 1978 and 2000, 113 patients were reoperated for coronary artery revascularization, 32 (28.3%) cases on beating heart without the use of CPB (Group II) and 81 (71.7%) cases under CPB and cardioplegic arrest (Group I). Mean age of Groups I and II were 61.3+/-5 and 57.4+/-7.3 years, respectively. RESULTS: Statistically significant difference was found between the two groups, favoring off pump surgery in the early postoperative findings with respect to low cardiac output, postoperative myocardial infarction and postoperative hospitalization duration until discharge. Operative mortality was not statistically different between groups and these figures for cardiopulmonary and off pump groups were 11/81 (13.5%), 1/32 (3.1%), respectively. CONCLUSION: Reoperations of coronary artery revascularization surgery without the use of CPB is more economic, necessitating less manipulations, free of side effects of CPB, less time consuming surgical procedure compared to reoperations performed under standard techniques. When performed with a refined technique and true indications, off pump coronary reoperations have mortality and morbidity advantages over the surgery performed under CPB, improvements in techniques and instruments off pump strategy must be in the surgeons armamentarium in coronary reoperations.

Adult↗
PubMed2001

Closed commissurotomy versus balloon valvuloplasty for rheumatic mitral stenosis.

BACKGROUND AND AIM OF THE STUDY: Closed mitral commissurotomy (CMC) and percutaneous mitral balloon valvuloplasty (PMBV) were compared by their initial results and Doppler echocardiographic data obtained at one week and one year after the procedure. METHODS: Of 580 patients with severe rheumatic mitral stenosis, 280 underwent CMC and 300 PMBV. The mean pre-procedural transmitral gradient (TMG) was 21 +/- 6 mmHg in the CMC group and 20 +/- 5 mmHg in the PMBV group (p = 0.6); the mean mitral valve area (MVA) was 1.1 +/- 0.2 cm2 in both groups. RESULTS: Mortality was 0.7% after CMC and 0.3% after PMBV; the primary success rates were 98.3% and 89% respectively (p <0.0001). Two CMC patients and three PMBV patients underwent emergency mitral valve replacement. At the first week, the mean TMG was decreased to 4 +/- 3 mmHg in the CMC group, and to 5.8 +/- 2 mmHg in the PMBV group (p <0.0001). The mean MVA was increased to 2.5 +/- 0.5 cm2 after CMC, and to 2.1 +/- 0.4 cm2 after PMBV (p <0.0001). After one year, TMG was 5.4 +/- 4 mmHg in the CMC group (p <0.0001) and 7.1 +/- 3 mmHg in the PMBV group (p <0.0001); MVA was 2.3 +/- 0.5 cm2 (p <0.0001) and 1.9 +/- 0.4 cm2 (p <0.0001), respectively. The results of CMC were significantly better (p <0.0001) with regard to TMG and MVA at these times. A significant decrease was also seen in mean left atrial diameter and pulmonary artery pressure in both groups (p <0.0001). CONCLUSION: Although satisfactory results can be achieved using either approach, CMC provides a higher primary success rate, greater MVA augmentation, and better technical control during the procedure, while reducing the cost. PMBV shortens in-hospital stay and eliminates the risk imposed by thoracotomy and anesthesia. Therefore, in our practice, when surgical intervention is contraindicated due to associated problems, PMBV may be the preferred approach, but exposure to radiation may be of concern in pregnant patients.

Adult↗
PubMed1999

Perinatal mitral valve interventions: a report of 10 cases.

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.

Adult↗
PubMed1999

Low-dose oral anticoagulation and antiplatelet therapy with St. Jude Medical heart valve prosthesis.

BACKGROUND AND AIM OF THE STUDY: Since 1986, the St. Jude Medical (SJM) mechanical heart valve prosthesis has been implanted in patients at the authors' institution. We present our experience of low-dose oral anticoagulation and antiplatelet therapy following SJM valve implantation. METHODS: Among 2,585 patients (mean age 40.3 +/- 13.5 years) living in a rural environment, 865 underwent aortic valve replacement (AVR), 1,231 mitral valve replacement (MVR) and 489 double valve replacement (DVR). All patients received 2.5 mg/day warfarin and a combination of antiaggregation therapy (dypridamole 3 x 75 mg/day plus aspirin 100 mg/day), irrespective of their prothrombin time and cardiac rhythm. RESULTS: Postoperatively, 139 adverse events occurred (51 in AVR patients, 58 in MVR, 30 in DVR). Operative mortality rate was 5.9%, 4.7% and 6.1%, respectively, in the three groups (overall mortality rate 5.4%). The most frequent cause of operative mortality was low cardiac output. During follow up, there were 88 anticoagulant hemorrhages (1.2%/patient-year (pt-yr)), 11 paravalvular leaks (0.2%/pt-yr), 52 thromboembolisms (0.7%/pt-yr), 60 mechanical valve thromboses (0.8%/pt-yr) and 78 reoperations (1.1%/pt-yr). These complications occurred in 101 patients after AVR, in 125 after MVR, and in 63 after DVR (4.2%, 3.7% and 4.6% per pt-yr, respectively). Patient age (p = 0.0004), concomitant surgery (p = 0.0017) and late valve-related complications (p = 0.0159) were statistically significant mortality factors after AVR. Previous surgery was a significant risk factor for operative mortality after MVR (p <0.05). Female gender (p = 0.0059) and age (p = 0.017) were significant risk factors for operative mortality after DVR (p <0.01). CONCLUSIONS: Following implantation of the St. Jude Medical mechanical heart valve prosthesis, a fixed dose of 2.5 mg/day warfarin and combined dipyridamole/aspirin provided satisfactory results in terms of thrombosis, embolism and bleeding.

Administration, Oral↗
PubMed1998

Optimization of synchronization delay in latissimus dorsi dynamic cardiomyoplasty.

BACKGROUND: Optimal synchronization delay (SD) for triggering the implanted cardiomyostimulators in patients undergoing latissimus dorsi dynamic cardiomyoplasty has not been clearly defined. Generally a synchronization delay time of 45 to 60 ms is used in the current practice, in which the implanted cardiomyostimulator stimulates the latissimus dorsi muscle 45 to 60 ms after mitral valve closure acquired with M-mode echocardiography. We investigated the effect of shortening or prolonging the delay time on cardiac functions. METHODS: We studied 10 patients who were in their first 2 years postoperatively. Three values for SD (SD = 0 ms, 45 to 60 ms, and 150 to 160 ms) were echocardiographically evaluated for their influence on both systolic and diastolic left ventricular parameters. RESULTS: Ejection fractions were 0.27 +/- 0.07, 0.28 +/- 0.07, and 0.32 +/- 0.06; peak aortic velocities were 0.85 +/- 0.8, 0.86 +/- 0.11, and 0.92 +/- 0.8 m/s; and velocity-time integrals were 0.16 +/- 0.03, 0.16 +/- 0.03, and 0.19 +/- 0.03 m for the SD values of 0, 45 to 60 ms, and 150 to 160 ms, respectively. Diastolic parameters were also measured. Isovolumetric diastolic relaxation time was 97.5 +/- 49, 97.20 +/- 44, and 111.8 +/- 49 ms; deceleration time was 83.67 +/- 32, 88.48 +/- 35, and 92.68 +/- 34 ms; and ratio or velocity-time integral of e wave to velocity-time integral of a wave was 3.09 +/- 0.98, 2.48 +/- 0.69, and 2.38 +/- 0.65 for the SD values of 0, 45 to 60 ms, and 150 to 160 ms, respectively. Systolic functions were better when SD was set at 150 to 160 ms, but there was a diastolic compromise. On the other hand, diastolic parameters were more favorable when SD = 0 (i.e., cardiomyostimulator triggered without delay) but the systolic assist was suboptimal. Systolic and diastolic parameters seemed relatively well-balanced with the current practice of setting the synchronization delay at 45 to 60 ms. CONCLUSIONS: The most favorable systolic effects were obtained with a prolonged delay of synchronization (150 to 160 ms), at some expense of diastolic functions. On the other hand, with a short or absent delay, diastolic parameters were improved but systolic parameters became suboptimal. Therefore, the current practice of setting the SD between 45 and 60 ms after echocardiographic mitral valve closure is suggested for the optimal timing for cardiomyostimulator stimulation in patients who have undergone latissimus dorsi dynamic cardiomyoplasty. Yet a great deal of individualization is necessary, and fixed preset values cannot definitely be determined because one setting does not fit all patients.

Aorta↗
PubMed1998

Coronary artery bypass grafting on the beating heart without the use of extracorporeal circulation: review of 2052 cases.

OBJECTIVE: A total of 2052 patients operated on with the off-pump technique (coronary artery bypass grafting on the beating heart without the use of extracorporeal circulation) between June 1993 and March 1996 are retrospectively reviewed. Predictors for early mortality, perioperative myocardial infarction, and low cardiac output state were statistically analyzed. METHOD: Our indications for an off-pump procedure were either patients with technically suitable coronary lesions (the vast majority) or patients who could not tolerate cannulation, hypothermia, or cardiopulmonary bypass because of the poor left ventricular function (198 patients) and/or associated diseases or conditions (73 patients). RESULTS: Overall operative mortality was 1.9% and perioperative myocardial infarction occurred in 59 patients (2.9%). According to logistic regression analysis, associated bronchial asthma (p = 0.0001), hypertension (p = 0.05), poor quality of the left anterior descending artery (p = 0.02), and ungrafted circumflex coronary artery disease (p = 0.007) were the early mortality predictors. Nonbypassed circumflex disease was also associated with a high incidence of perioperative myocardial infarction and low cardiac output state. No homologous blood or packed red cell transfusion was required in 74.2% of the patients. CONCLUSION: On the basis of the presented data, off-pump coronary artery bypass grafting appeared to be a safe and effective technique in selected patients with appropriate coronary lesions.

Adult↗
PubMed1998

Bloodstream, respiratory, and deep surgical wound infections after open heart surgery.

Nosocomial infections are one of the most feared complications after open heart surgery. A large retrospective study was conducted to evaluate the nature and scope of the problem. Between 1992 and 1998, 9352 patients who had undergone open heart surgery were evaluated. Bloodstream infections, pneumonia, and deep sternal wound infections were included. Univariate and logistic regression analyses were conducted to identify the high-risk patients that were likely to become infected. Three hundred forty-six infections in 276 patients were diagnosed. Age, preoperative albumin level, banked blood requirement, duration of operation, diabetes mellitus, previous open heart surgery, moderate or severe pericardial adhesions, obesity, postoperative low cardiac output, and postoperative cerebrovascular accident were found to be significant in univariate and logistic regression analyses for infectious outcome. Univariate analysis also revealed additional significant factors: fresh frozen plasma requirement, duration of cardiopulmonary bypass and cross-clamp, preoperative high levels of blood urea and glucose, presence of occlusive peripheral arterial disease, preoperative history of hypertension, and nasal carriage of Staphylococcus aureus. Methicillin resistant S. aureus was involved in 58.4% of the infections. Risk factors should be individualized for patients and every effort should be carried out to minimize infectious outcome.

Adolescent↗
PubMed1998

Mitral valve replacement with St. Jude Medical prosthesis and low-dose anticoagulation in patients aged over 50 years.

BACKGROUND AND AIMS OF THE STUDY: These studies were designed to assess the effect of low-dose anticoagulation in elderly patients after mitral valve replacement. METHODS: Between 1986 and 1995, 250 patients aged > or = 50 years underwent isolated mitral valve replacement at the Cardiovascular Surgery Clinic of Turkiye Yuksek Ihtisas Hospital. The overall hospital mortality rate was 8%. Postoperatively, all patients received 2.5 mg/day warfarin, and 225 mg/day dypridamole and 250 mg/day aspirin following removal of mediastinal tubes. This regimen was continued indefinitely thereafter. RESULTS: Postoperatively, the mean International Normalized Ratio (INR) was 1.4 +/- 0.67 (range: 0.9 to 4.19) and mean prothrombin time 13.33 +/- 1.98 min (range: 11.7 to 21.3 min). Mean follow up was 1.42 +/- 1.2 years (range: 2 months to 8.3 years); total cumulative follow up was 322.75 patient-years (pt-yr). During follow up, six patients (1.85% per pt-yr) developed thromboembolic complications (including mechanical valve thrombosis), two (0.62% per pt-yr) developed oral anticoagulant-related bleeding, and two (0.62% per pt-yr) developed paravalvular leak. Five patients died during follow up (late mortality rate 1.2% per pt-yr). The nine-year actuarial survival rate was 93.9 +/- 4.8% for the entire group. CONCLUSIONS: Low-dose oral anticoagulation after mitral valve replacement with St. Jude Medical prosthesis in elderly patients provided satisfactory clinical results.

Actuarial Analysis↗
PubMed1997

A comparison of the early and midterm results after dynamic cardiomyoplasty in patients with ischemic or idiopathic cardiomyopathy.

OBJECTIVE: The main goal of this study is to determine the efficiency of the cardiomyoplasty procedure on patients with cardiomyopathy of different origins (ischemic and idiopathic origins). METHOD: Between June 1993 and August 1995, 24 patients underwent dynamic cardiomyoplasty with the left latissimus dorsi muscle in our institution. Early and midterm results, as well as the changes in hemodynamics and functional status during follow-up, were compared. RESULTS: Early mortality rate was 20.8% (five patients). Concomitant coronary revascularization, a preoperative left ventricular ejection fraction below 20%, and a functional capacity of class IV (intermittently) were associated with early mortality. The mean follow-up time was 17.3 months. Survival analysis (including early mortality) extending to the twenty-fourth month revealed no difference between the ischemic and idiopathic groups (55% vs 85%, respectively, p = 0.09). Functional status improved in the both groups. Ejection fractions were improved after cardiomyoplasty in all patients, regardless of their cause. Cardiac indices were higher 6 months after the operation. Changes in pulmonary capillary wedge pressure, peak pulmonary artery pressure, and left ventricular end-diastolic volume were not significant. CONCLUSION: Although cardiomyoplasty improves functional capacity and hemodynamics in patients with both idiopathic and ischemic cardiomyopathy, the idiopathic group is thought to achieve optimal benefit with regard to lower complication rates and lower early mortality expectancy owing to the absence of concomitant coronary revascularization.

Adult↗
PubMed1997

Treatment of functional tricuspid regurgitation by bicuspidalization annuloplasty during mitral valve surgery.

BACKGROUND AND AIMS OF THE STUDY: Surgical treatment of functional tricuspid regurgitation associated with advanced valvular disease remains controversial, mainly due to the difficulty in choosing between valve replacement or reconstructive surgery. Failure to correct tricuspid regurgitation during valvular surgery carries a poor prognosis, as reoperation may represent a significant risk to the patient. Thus correct tricuspid valve surgery is vital to achieve improved early and long-term clinical results. METHODS: A total of 142 patients underwent concomitant tricuspid annuloplasty with mitral valve replacement and their clinical outcome was assessed. RESULTS: Overall hospital mortality rate was 11.3%. Seven patients died during follow up. The overall actuarial survival rate for 10 years was 74.1 +/- 14.2%. Postoperatively, 75.8% of the patients had no residual tricuspid insufficiency, while 24.2% had first- or second-degree tricuspid insufficiency and were treated medically. All patients were in NHYA functional class I or II postoperatively. CONCLUSION: Clinically, it is important to assess the severity of functional tricuspid insufficiency before and/or during the operation. Bicuspidalization annuloplasty for functional tricuspid insufficiency has provided good results, with a low incidence of reoperation and significant clinical improvement. The technique could be used in most patients with functional tricuspid regurgitation.

Adolescent↗
PubMed1996

Long term results of mitral valve replacement with preservation of the posterior leaflet.

BACKGROUND AND AIMS OF THE STUDY: It is commonly held that preservation of the annulo-ventricular continuity during mitral valve replacement has a beneficial effect on postoperative ventricular function. This paper presents our eight-year experience with this technique. MATERIALS AND METHODS: From 1986 to December 1992, 120 patients with rheumatic valve disease underwent mitral valve replacement (MVR) combined with preservation of the posterior leaflet of the mitral valve. The mean age was 33.87 years (range 16 to 63). The preoperative New York Heart Association (NYHA) class was III in 64% of the patients and IV in 3%. The early (30 day) mortality rate was 2.5% (3/120). Follow up was 100% complete. The total cumulative follow up was 477 patient-years (pty) with a mean 3.94 years (range: 2-8 years). RESULTS: The actuarial survival rate (including hospital mortality) was 87.6% at eight years. Advanced age (p = 0.0457), increased preoperative functional capacity (p = 0.0251), increased preoperative end-systolic diameter (p = 0.0352) and combined tricuspid reconstruction (p = 0.0001) were found to be independent parameters for a lower actuarial survival rate. Six patients (1.25%/pty) developed thromboembolic complications. Two of these were cerebrovascular accidents (0.41%/pty) and four were caused by mechanical valve thrombosis (1.83%/pty). Freedom from thromboembolic complications (including mechanical valve thrombosis) was 89.8% +/- 7.9%. Fifteen patients (3.14%/pty) developed valve failure, four (0.83%/pty) mechanical valve thrombosis and nine (1.88%/pty) bioprosthetic valve failure. Freedom from reoperation was 60.7% +/- 16.1%. One patient with a St. Jude Medical valve (0.2%/pty) suffered from prosthetic valve endocarditis. Three patients (0.62%/pty) died during the follow up period, and, freedom from all valve related complications was 51.4% +/- 16.1% at eight years. CONCLUSION: Preservation of the posterior leaflet during mitral valve replacement reduces the risk of early mortality and did not cause additional complications to the patients. Despite the beneficial effects of this technique in the long term this technique did not increase the long term survival in patients with associated impaired valvular and/or ventricular function.

Adolescent↗
PubMed1996

Hemodynamic effects of acute intestinal ischemia.

Twelve animals entered in this study with the aim of documenting that superior mesenteric artery small occlusions lasting for one hour have adverse effects on the myocardium. Three hours after cross clamp removal CO decreased to 1.07 +/- 0.11 from 1.99-0.09 a preoperative value (p < 0.01) and PCWP increased to 17 +/- 3 from 8 +/- 3 a preoperative value. MOE reduced to 40-5% 3 hours after cross clamp removal. MLE was -0.21 +/- 0.11 three hours after clamp removal. Changes in MOE and MLE were commented as a defect in myocardial aerobic metabolism. As a result of this study it was concluded that toxic mediators are released from the intestine being reperfused after temporary occlusions of the SMA impair myocardial metabolism, resulting in decreased hemodynamic functions.

Animals↗
PubMed1995

Routine coronary arteriography before abdominal aortic aneurysm repair.

BACKGROUND: As cardiac complications constitute the principal cause of early and late morbidity and mortality after the surgical treatment of abdominal aortic aneurysm (AAA), a prospective study was planned to evaluate the effects of revascularization of coronary arteries on survival after AAA repair during early and long-term follow-up periods. PATIENTS AND METHODS: A total of 125 patients underwent elective repair of AAA between 1986 and 1994. Coronary arteriography was performed in all cases. All cases with critical left anterior descending artery (LAD) lesions underwent a coronary artery bypass operation either simultaneously or shortly before AAA repair. In addition, percutaneous transluminal coronary angioplasty (PTCA) was performed for symptomatic and critical stenosis of arteries other than the LADs, or if noncritical but symptomatic stenosis of the LADs existed. Early and late follow-up data were obtained for all cases, and late-term cumulative survival rates were calculated. RESULTS: Coronary artery lesions were found in 66 (53%) cases. In 24 cases, AAA repairs were performed 2.3 (mean) months after coronary artery bypass grafting (CABG), whereas in 4 cases both procedures were performed simultaneously. PTCA was performed in 4 cases 3 to 4 days prior to the abdominal surgery. Even though the coronary artery lesions were found inoperable in 7 cases, these patients underwent repair of AAA because of rapidly expanding and painful aneurysms. Early mortality rate was 4% (5 cases), in which 3 of these were from the group inoperable for CABG. A mean follow-up of 3.17 years (3 to 87 months) was achieved for all discharged patients. Cumulative survival rates for 6 months and 1, 2, 3, and 6 years were 99%, 99%, 95%, 93%, and 89%, respectively. CONCLUSIONS: The results of this study emphasize the importance of coronary artery revascularization for early, and especially for late, survival after AAA repair.

Adult↗
PubMed1995

Late results of mitral valve replacement with Carpentier-Edwards high profile bioprosthesis in young adults.

Carpentier-Edwards (C/E) high profile supra-annular porcine bioprostheses were implanted in 163 patients between September 1982-February 1987 in the mitral position due to rheumatic disease. The patients' ages ranged between 15 and 58 years (mean: 36.5 +/- 11.5). One hundred-two of the patients (62.5%) were female. The hospital mortality was 9.8% (16/163). The total cumulative follow-up period was 1093 patient-years (p-y) with a mean of 7.3 +/- 3.5 p-y (range 6 months-12 years). Linearised occurrence rates of the late complications were as follows: Thromboembolism 0.82%/p-v, anticoagulant-related bleeding 1.0%/p-y, prosthetic valve endocarditis 0.09%/p-y. Actuarial survival rates for 5 and 12 years were 87% +/- 6% and 76% +/- 9%, respectively, with 95% confidence limits. Freedom from structural deterioration was 92% +/- 5% for 5 years and 44% +/- 11% for 12 years. Freedom from all valve-related complications was 81% +/- 7 for 5 years and 26% +/- 9 for 12 years. In conclusion, this prosthesis provides satisfactory clinical performance in young population despite the high risk of degeneration with good prognosis and better tolerability of reoperation.

Actuarial Analysis↗
PubMed1995

Cardiomyoplasty.

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Cardiomyoplasty↗
PubMed1995

Effects of dynamic cardiomyoplasty on right ventricular function.

This study was planned to document the right ventricular function immediately after cardiomyoplasty. Right ventricular volumes were calculated with the use of fast response thermistor. Right ventricular end-diastolic volume was reduced from 91 +/- 8 mL/M2 to 75 +/- 7 mL/M2 (p < 0.05) and right ventricular end-systolic volumes increased from 51 +/- 5 mL/M2 to 59 +/- 4 mL/M2 24 hours after the operation. Central venous pressure was raised from 2 +/- 1 to 9 +/- 3 mm H2O. These changes were interpreted as impairment of the right ventricular diastolic function. Cardiac index raised from 1.8 +/- 0.5 L/M2 per minute to 2.7 +/- 0.3 L/m2 per minute within a period of 7 days (p < 0.05). As a result of this study, we concluded that preoperatively normal right ventricular function deteriorates after the cardiomyoplasty. In the intensive care unit volume balance must be carefully monitored to avoid creating right ventricular dysfunction.

Adult↗