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Biomedical subjects

K Bayazit

Publications and source records attributed to K Bayazit.

At least 55 records · Page 3Linked to original sources
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↗
PubMed1995

Low dose anticoagulation after St. Jude Medical prosthesis implantation in patients under 18 years of age.

Between September 1986 and January 1994, 129 St. Jude Medical prostheses were implanted in 113 patients who were 18-year-old or younger at the Cardiovascular Surgery Clinic of Turkiye Yuksek Ihtisas Hospital. Thirty-seven patients underwent aortic, 60 patients mitral and the remaining 16 patients double valve replacement. Overall hospital mortality was 7.9% (9/113). All patients received 2.5 mg/day warfarin from the first postoperative day, in addition 225 mg/day dipyridamole and 100 mg/day aspirin was given following the removal of mediastinal tubes. This regimen was continued indefinitely thereafter. Follow up period ranged between 2-94 months. Total follow up experience was 276.4 patient-years. There were five late deaths; the cause of death was prosthetic valve thrombosis in two patients, intracerebral hemorrhage in one, cardiomyopathy in one, and sudden death in one. Other late complications included one endocarditis, a further anticoagulant related bleeding and one paravalvular leak. There was no case of cerebral or peripheral embolism reported. Seven-year actuarial survival was 92.4 +/- 6.8% for the entire group, 84.6 +/- 13.8% after mitral and 100% after aortic or double valve replacement. In conclusion, low dose oral anticoagulation after heart valve replacement with St. Jude Medical prosthesis in this age group showed satisfactory clinical results.

Adolescent↗
PubMed1994

The beneficial effects of aminophylline administration on heparin reversal with protamine.

The aim of this study was to demonstrate the beneficial effects of aminophylline on protamine cardiotoxicity. Thirty-four patients were examined, 17 of whom received aminophylline 3 mg/kg before protamine administration, being the study group, while the other 17, being the control group, did not. All cardiac output and biochemical measurements were evaluated 5 min following protamine administration. The cAMP level was 43.4 +/- 3.51 pmol/ml in the study group and 18.7 +/- 2.98 in the control group (P < 0.0001) before protamine administration, while the oxygen extraction rate decreased from 49% to 44 +/- 2% in the control group, and from 51.2% to 47 +/- 3% in the study group (P < 0.03). The N-acetyl glucosaminidase value was 16.9 +/- 13.9 pmol/ml in the study group and 27.8 +/- 1.47 pmol/ml in the control group (P < 0.01), and myocardial lactate extraction was -0.20 +/- 0.03 in the control group and -0.07 +/- 0.07 in the study group (P < 0.001). The left ventricular stroke work index was 28.6 +/- 3.14 gm/m2 in the control group and 37 +/- 6.77 gm/m2 in the study group (P < 0.002). The findings of this study led us to conclude that the adverse effects of heparin neutralization using protamine can be relieved by aminophylline.

Acetylglucosaminidase↗
PubMed1994

Vascular complications related to percutaneous insertion of intraaortic balloon pumps.

The hemodynamic effects of intraaortic balloon pumps (IABPs) are well known. The use of IABPs is prone to many complications, including those classified as vascular. These complications are said to be more frequent with percutaneous insertion techniques. These complications and the algorithm for identifying patients who are most likely to suffer vascular complications were evaluated in a retrospective manner in a group of patients that received percutaneous IABPs. The study group consisted of 449 patients. The mean age of these patients was 53.6 +/- 12.8 years (range, 18 to 80 years), and 24.7% were female. The early mortality rate of these patients was 53.2%. The mortality for patients in whom vascular complications developed was significantly higher than that in the patients who did not suffer any vascular complications (65.7% versus 50.8%; p = 0.018). Minor or major vascular complications developed in 17.4% (n = 78) of the patients. There was no statistical difference in the frequency of complications between the patients who received a sheathless IABP and those who received a sheathed IABP. Ischemic complications occurred in 16.6% of the patients who received a sheathless IABP and in 17.6% of the patients with sheathed IABPs (p < 0.05). Diabetic patients (relative risk, 2.5), female patients (relative risk, 1.83), patients with peripheral vascular disease (relative risk, 3.69), and patients undergoing coronary artery bypass operations (relative risk, 2.08) were at increased risk for suffering vascular complications. These risk factors should be evaluated before insertion of an IABP, and routes other than percutaneous femoral insertion are preferred if the patient is IABP dependent.

Acute Kidney Injury↗
PubMed1994

Coronary sinus retroperfusion combined with intraaortic balloon pumping to perfuse the acutely ischemic myocardium.

This study was planned to show the effect of retroperfusion and intraaortic balloon pumping (IABP) on myocardial hemodynamic recovery. Twelve dogs entered this study. Half of them received IABP and coronary sinus retroperfusion (CSPR) combination (Group II) and the remaining received IABP alone (Group I). Left anterior descending artery was occluded for a period of three hours. 15 minutes after occlusion IABP and IABP + CSRP were initiated. The average cardiac output was 1.41 +/- 0.18 L/min in the group I and 1.72 +/- 0.24 L/min in the group II (p < 0.03) after 3 hours of occlusion. Mean arterial pressure was 82.1 +/- 4.8 mmHg in the group I and 89.7 +/- 2.6 mmHg in the group II (p < 0.03). On the basis of this study it was concluded that CSRP + IABP could be an alternative treatment to IABP alone during the acutely developing ischemia.

Acute Disease↗
PubMed1994

Hypertrophic obstructive cardiomyopathy in combination with anomalous insertion of papillary muscle directly into anterior mitral leaflet and "sawfish" systolic narrowing of the left anterior descending coronary artery.

This report describes an unusual case of subaortic stenosis in which hypertrophic obstructive cardiomyopathy was found in combination with both anomalous insertion of papillary muscle directly into the anterior mitral leaflet and "sawfish" systolic narrowing of the left anterior descending coronary artery. Definitive diagnosis was made on operation. We freed the left anterior descending coronary artery by incising the muscular bridge, resected both papillary muscles, and replaced the mitral valve.

Adult↗
PubMed1993

Warm blood cardioplegia: ultrastructural and hemodynamic study.

Forty patients with coronary artery disease were included in this study. Half of them received cold crystalloid and cold blood cardioplegia (group 1), and half received normothermic blood cardioplegia (group 2). In group 1, left ventricular stroke work index was 24 +/- 3 g.m/m2 1 hour after the operation, 29 +/- 8 g.m/m2 12 hours after the operation, and 33 +/- 6 g.m/m2 24 hours after the operation. In group 2, left ventricular stroke work index was 37 +/- 4 g.m/m2 1 hour after the operation, 37 +/- 4 g.m/m2 12 hours after the operation, and 44 +/- 7 g.m/m2 24 hours after the operation. Myocardial oxygen extraction 20 minutes after the termination of cardiopulmonary bypass was 0.28 +/- 0.03 in group 1 and 0.44 +/- 0.08 in group 2. Myocardial lactate extraction at the same time was -0.09 +/- 0.02 in patients receiving cold blood cardioplegia and 0.17 +/- 0.07 in patients receiving normothermic blood cardioplegia. Electron microscopic study revealed no calcium accumulation in the mitochondria in group 2 patients, whereas calcium accumulation was present in the other group.

Aged↗
PubMed1993

Low-dose anticoagulant management of patients with St. Jude Medical mechanical valve prostheses.

Between February 1984 and December 1990, 622 St. Jude Medical valves were implanted in 548 patients. There were 382 males (69.7%) and 166 females (30.3%) with a mean age of 32.3 +/- 11.9 years (range 9-68 years). Sixty-eight percent of the patients were referred from rural areas. Three hundred and forty patients underwent aortic valve replacement (AVR), 134 had mitral valve replacement (MVR), and 74 had aortic and mitral valve replacement (DVR). The hospital mortality was 4.7% (16/340) for AVR, 6.7% (9/134) for MVR and 10.8% (8/74) for DVR. Follow-up period ranged from 1.1 to 7.2 years. Total follow-up was 1317.3 patient-years (py). All patients received 2.5 mg warfarin, 225 mg dipyridamole, and 250 mg aspirin daily, regardless of prothrombin time and cardiac rhythm. Thromboembolism was observed in 10 patients (0.75 py); there were 3 mortalities (0.22% py). Valve thrombosis occurred in 4 patients (0.30% py): 3 in the MVR group (0.94% py) and 1 in the AVR group (0.11% py). Hemorrhage occurred in 19 patients (1.44% py) with 11 fatal outcomes (0.83% py). It is concluded that a random daily dose of 2.5 mg warfarin with 225 mg dipyridamole and 250 mg aspirin is sufficient for safe anticoagulation without the need for serial prothrombin-time adjustments.

Adolescent↗
PubMed1993

Pseudoaneurysm of the tibioperoneal trunk.

A young woman with an iatrogenic coagulation defect related to a mechanical mitral valve prosthesis developed a pseudoaneurysm of the tibioperoneal trunk after a minor blunt injury. The importance of minor blunt trauma in such cases and the surgical approach are reviewed.

Adult↗
PubMed1993

Effects of prostacyclin on spinal cord ischemia: an experimental study.

BACKGROUND: Paraplegia after thoracic aortic aneurysm has an incidence of 2.2% to 24%. This study was planned to show the beneficial effects of prostacyclin on spinal cord ischemia. METHODS: Twelve rabbits underwent 30 minutes of aortic occlusion. Six rabbits received prostacyclin, whereas the remaining rabbits did not. Prostacyclin administration was started with a rate of 5 ng/kg/min 5 minutes before aortic occlusion. This dosage was increased to 25 ng/kg/min during aortic occlusion. Prostacyclin administration after aortic occlusion was maintained for a period of 5 minutes. During this period, prostacyclin dosage was 5 ng/kg/min. RESULTS: One rabbit in the prostacyclin group and five rabbits in the control group were paraplegic. Arterial pressure proximal to the clamp was 65 +/- 7 mm Hg before aortic occlusion and 78 +/- 10 mm Hg during aortic occlusion in the control group and 68 +/- 12 mm Hg before aortic occlusion and 65 +/- 6 mm Hg during aortic occlusion in the prostacyclin group. Arterial pressure distal to the clamp was 11 +/- 4 mm Hg during aortic occlusion in the control group and 18 +/- 5 mm Hg during aortic occlusion in the prostacyclin group (p = 0.02). CONCLUSIONS: Intravenous prostacyclin reduced the neurologic injury caused by spinal cord ischemia and reperfusion after 30 minutes of aortic occlusion in the rabbit model.

Animals↗
PubMed1992

Aorto-pulmonary artery fistula: an unusual complication of ascending aortic aneurysm.

We report an unusual outcome of an ascending aorta aneurysm ruptured into the main pulmonary trunk. After successful emergency repair, an acute respiratory distress syndrome developed perioperatively and complicated the postoperative period. The patient could not be weaned from mechanical ventilation for a long time. The patient was discharged on the 62nd day of admission in good condition.

Aorta↗
PubMed1992

Surgical approach to pseudoaneurysms with Behçet's disease.

One of the arterial complications of Behçet's disease, arterial false aneurysms, has a sudden onset of symptoms and high mortality risk if left untreated. Four cases with arterial pseudoaneurysms of 3 male patients is reported and the choice of surgical intervention is emphasized. It is underlined that PTFE grafts are the graft of choice in reconstructions for arterial complications of Behçet's disease.

Adult↗
PubMed1989

In vitro thrombolysis of thrombosed valve prostheses: therapeutic considerations of left-sided thrombotic lesions.

Six thrombosed Bjørk-Shiley mitral valve prostheses which had been removed in emergency reoperations between November 1985 and December 1986 underwent in vitro thrombolysis with urokinase. After a mean period of 14 +/- 3 h of in vitro fibrinolysis, lysis of thrombus was observed, but large fragments of organized thrombus were released into the medium, suggesting that thrombolytic therapy should not be used for thrombotic occlusions on the left side of the heart, as the risk of systemic embolization is high.

Heart Valve Prosthesis↗
PubMed1989

Congenital coronary artery fistulas. Diagnostic and surgical considerations.

Between 1974 and April, 1988, 9 patients with congenital coronary artery fistulas underwent surgical repair. Of these, 4 were female and 5 male, ranging in age from 6 to 50 years (mean 28.2 +/- 18.9). Seven patients were symptomatic (congestive heart failure and/or angina), whereas in 2 patients the diagnosis was established through the investigation of an asymptomatic continuous murmur. The origin of the fistula was the left main coronary artery in 1, left anterior descending artery (LAD) in 2, circumflex artery (Cx) in 3, Cx + LAD in 2 and LAD + right coronary artery in 1 patient. The sites of termination of the fistulous tract were the pulmonary artery in 6, the right atrium in 1, the right ventricle in 1 and the left ventricle in 1 patient. In 2 cases the fistulous tracts were ligated without utilizing cardiopulmonary bypass (CPB). In 7 cases CPB was instituted and in 6 of these the fistulous communications were closed from within the termination chamber, in 1 patient the fistula was closed through a coronary arteriotomy during elective ventricular fibrillation. There was no operative mortality and long term follow-up was uneventful after a mean follow-up of 5.4 +/- 5.2 years, with 8 patients still completely asymptomatic. Surgical therapy is recommended for patients having coronary artery fistulas in order to prevent fistula-related complications. In those cases requiring CPB, closure of the fistula from the involved chamber only is suggested.

Adolescent↗
PubMed1989

The association of lower extremity peripheral vascular disease in patients undergoing coronary bypass surgery.

The association of lower extremity peripheral vascular disease (PVD) in patients undergoing coronary artery bypass (CAB) has been studied in two groups of patients who have been operated upon between January and May 1987. Group 1 consists of 125 cases in which only resting ankle-arm pressure index (AAPI) were evaluated. Group 2 consists of 50 cases where both resting and after exercise AAPI were recorded. In total, 17 cases of one extremity and in 10 both lower extremity resting AAPI were below 0.9 (15.4%). In Group 2 comparison of resting and after exercise AAPI on both sides showed no statistically significant difference. However in Group 2, 13 cases (26%) had after exercise AAPI below 0.9 and in 26 (52%) cases after exercise AAPI were lower than the resting AAPI. This study showed that, although the coexistence of PVD in patients undergoing CAB is not as high as the coexistence of CAD in patients undergoing peripheral vascular procedures, this percentage can increase when the presence of PVD is evaluated with an exercise test whenever possible.

Adult↗
PubMed1987

Postcardiotomy right ventricular failure: experience with pulmonary arterial balloon counterpulsation and pulmonary arterial venting.

From 1981 through 1985, 3,057 patients underwent cardiac operations using cardiopulmonary bypass (CPB) at our institution. When we reviewed these cases, we found that in ten cases (0.32%) right ventricular or biventricular failure had prevented weaning from CPB. All ten patients were also refractory to pharmacologic intervention and to systemic intraaortic balloon pumping. Two patients had isolated right ventricular failure, and the other eight had biventricular failure. Four patients had had previous pulmonary hypertension. Of the ten patients who could not be weaned, three were treated with pulmonary arterial balloon counterpulsation (PABC), and seven underwent pulmonary arterial venting (PAV). Procedures performed concomitantly with PABC included left heart bypass in one case and creation of an atrial septal defect in another case. All of the PAV group underwent concomitant intraaortic balloon pumping. One PABC patient and four PAV patients could be weaned from CPB. All who were treated with PABC eventually died, but there are three long-term survivors in the PAV group. In light of this study, biventricular unloading with PAV appears to be a valid method of treating right ventricular or biventricular failure.

Journal Article↗