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Nihan Kayalar

Publications and source records attributed to Nihan Kayalar.

11 recordsLinked to original sources
PubMed2005

Reversed-J inferior sternotomy for awake coronary bypass.

Many approaches for minimally invasive coronary bypass surgery are available and to further decrease the invasiveness, coronary artery bypass grafting has been performed under high thoracic epidural anesthesia without endotracheal intubation in the last years. Less invasive approach to coronary artery bypass graft operations is possible through combination of the high thoracic epidural anesthesia and a reversed-J sternotomy, and coronary revascularization can be accomplished without any additional technical difficulties and with a good exposure of both the left anterior descending artery and the left internal thoracic artery. This technique is less traumatic for patients and provides practical better oxygenation and shorter hospital stay.

Anesthesia, Epidural↗
PubMed2005

Melatonin protects against ischemia/reperfusion injury in skeletal muscle.

Melatonin has been shown to diminish ischemia-reperfusion (I/R) injury in many tissues. The main aim of this study was to evaluate the protective antioxidant effect of melatonin in skeletal muscle during I/R injury. Wistar albino rats were randomly divided into three groups. Hindlimb ischemia was achieved by clamping the common femoral artery in two groups but not in control group. Limbs were rendered ischemic for 1.5 hr; at the end of the reperfusion period of 1.5 hr muscle tissue samples were taken for the histological evaluation and biochemical analysis. Melatonin (10 mg/kg) was injected i.p. in the I/R + Mel group at the onset of ischemia whereas the vehicle solution was injected in the I/R group. In I/R + Mel group histological damage was significantly less than in the I/R group (P < 0.001). In the I/R + Mel group, the mean malonedialdehyde level was lower than in the I/R group (P < 0.01) and was quite near to the levels in the control group (P > 0.05). Glutathione levels were found to be reduced in the I/R group compared with the control (P < 0.01) and I/R + Mel group (P < 0.01). Melatonin has a protective effect against I/R injury in skeletal muscle and may reduce the incidence of compartment syndrome, especially after acute or chronic peripheral arterial occlusions.

Animals↗
PubMed2004

Off-pump awake coronary revascularization using bilateral internal thoracic arteries.

BACKGROUND: A new technique has been developed that permits complete arterial revascularization of the lateral and/or inferior wall of the heart using in situ bilateral internal thoracic artery grafts in awake patients. This technique, without cardiopulmonary bypass and mechanical ventilation, creates the least invasive revascularization method for the lateral and/or posterior wall of the heart yet described. METHODS: In 7 patients double or triple vessel coronary artery bypass grafting was performed without general anesthesia. A high thoracic epidural anesthesia was started one hour before surgery. Bilateral internal thoracic arteries were harvested and all anastomoses were performed with the off-pump technique by standard median sternotomy. Circumflex, or the right coronary artery, were anastomosed with bilateral internal thoracic arteries using a heart positioner. Six patients received double bypass grafting and one patient received triple bypass grafts (bilateral internal thoracic arteries and one radial artery). RESULTS: All patients remained awake throughout the whole procedure. There was no perioperative myocardial infarction or mortality. Pneumothorax was observed in three patients, but it was repaired in two. Only one patient completed the procedure with unilateral pneumothorax. There were no hemodynamic and pulmonary problems during lateral or posterior wall revascularization. Two patients required unexpected coronary endarterectomy during circumflex and right coronary artery anastomoses. CONCLUSIONS: Complete arterial revascularization by median sternotomy using in situ bilateral internal thoracic artery grafts without general anesthesia is a feasible and safe procedure for multivessel disease. This approach gives a chance for awake revascularization of the right and/or circumflex coronary artery.

Adult↗
PubMed2004

Combined coronary artery bypass grafting and lung surgery.

Combined coronary bypass and lung surgery was performed in 3 patients. Through a median sternotomy or a left thoracotomy, bypass grafting was performed on beating heart or under cardiopulmonary bypass, followed by the lung operation. The lung lesion was diagnosed as carcinoma in 2 patients and hydatid cyst in 1 patient. With few exceptions, beating heart coronary bypass through a median sternotomy can be performed in a combined operation.

Aged↗
PubMed2004

Complete off-pump coronary revascularization in patients with dialysis-dependent renal disease.

Patients who have dialysis-dependent renal disease frequently present with coronary artery disease but are considered at high risk for coronary artery bypass grafting. From 1 September 2000 through 31 August 2003, we performed complete off-pump coronary revascularization in 6 patients who had end-stage dialysis-dependent renal failure, and we prospectively studied the perioperative and early postoperative results. The effect of off-pump coronary artery bypass grafting on mortality, morbidity, postoperative complications, and transfusion requirements in this group of patients was investigated. No perioperative deaths or ischemic cardiac events were observed after off-pump coronary artery bypass grafting. In all patients, anginal symptoms were relieved during the postoperative period. The mean duration of follow-up was 172 +/- 12.4 months. Patients with dialysis-dependent chronic renal failure who present with coronary artery disease should be thoroughly evaluated preoperatively for risk factors and coexistent severe diseases. We believe that in patients with end-stage dialysis-dependent chronic renal failure, off-pump coronary revascularization is a good alternative.

Adult↗
PubMed2003

Markers of myocardial ischemia in the evaluation of the effect of left anterior descending coronary artery lesion and collateral circulation on myocardial injury in 1-vessel off-pump coronary bypass surgery.

BACKGROUND: The purpose of this study was to use serum markers for myocardial tissue damage to evaluate the effect of the severity of left anterior descending artery (LAD) lesions after 1-vessel off-pump coronary artery bypass grafting. METHODS: A consecutive series of 20 patients with a totally occluded LAD and only retrograde filling (group T; n = 10) or critical stenosis (70%-99%) and only antegrade filling (group C; n = 10) were included in this study. One patient in group C who displayed no increases in the levels of markers for myocardial ischemia was excluded from the study because of the intraoperative repetition of the anastomosis. Creatine kinase activity (CK), CK-MB activity, and CK-MB mass, myoglobin, lactate, and cardiac troponin I (cTnI) concentrations were determined in venous blood samples taken immediately before and after the anastomosis and at 4, 8, 12, 24, and 48 hours postoperatively. RESULTS: There were no perioperative myocardial infarctions. One patient in group T developed low cardiac output syndrome 48 hours after the operation and died after 1 month. His enzyme levels did not increase in the first 2 days postoperatively. Anastomosis times were similar for the T and C groups (6.85 +/- 0.9 minutes versus 8.4 +/- 2.2 minutes, respectively; P =.069). The levels of all cardiac markers except cTnI increased significantly in the first 24 postoperative hours. CK-MB activity, CK-MB mass concentration, and cTnI concentration were not different between the 2 groups. Four patients in each group were evaluated for the patency of the anastomosis, and all control angiography and myocardial scanning tests showed patent anastomoses and no ischemia. CONCLUSIONS: One-vessel off-pump coronary artery bypass grafting can be performed safely in patients with serious LAD stenosis and borderline antegrade blood flow without the need for any coronary collateral circulation support. A short anastomosis time prevents myocardial injury during off-pump coronary surgery.

Adult↗
PubMedDate not supplied

Long-term outcome after total correction of tetralogy of Fallot in adolescent and adult age.

Although most patients with tetralogy of Fallot (TOF) undergo radical repair during infancy and childhood, patients remaining undiagnosed and untreated until adulthood can still be treated. These patients have either a previous palliative or natural collateral circulation to the lung or a mild form of right ventricular outflow tract (RVOT) obstruction. The aim of this study is to analyze the perioperative and long-term results of radical corrective procedures in patients who reached adult ages. Two hundred and seven patients with TOF underwent complete correction between 1985-and 2002, 64 (30.9%) of whom were aged 14 years or more. The mean age at corrective repair for this group was 20.6 +/- 7.5 years (range 14 to 49 years). Only two patients had previous modified Blalock-Taussig shunts. In 44 patients (68.7%) besides infundibular resection, a transannular gluteraldehyde-treated pericardial patch was used to reconstruct right ventricular outflow tract (RVOT). Only infundibular patching was used in 15 patients (23.4%) and infundibular muscular resection with primary closure of right ventricle was performed in five patients (7.8%). Hospital mortality was 3.1% with two patients. Four patients (6.2%) underwent reoperation because of recurrent ventricular septal defect (VSD) with/without residual obstruction or pulmonary regurgitation. All survivors were in NYHA class I (42) or II (17). Late mortality was recorded in two patients and 16-year actuarial survival was 89.2%+/- 4.9%. The significant negative predictors of late survival determined by univariate analysis were reoperation <0.018) and associated cardiac anomalies <0.011). Multivariate analysis showed that there was no negative predictor of late-term mortality. Corrective procedures in adult patients with TOF can be performed successfully compared to patients who underwent operation during infancy and childhood.

Adolescent↗
PubMedDate not supplied

Surgery for chronic total occlusion of the left main coronary artery--myocardial preservation.

We report seven patients with chronic total occlusion of the left main coronary artery that were operated in our institution and discuss the myocardial preservation options in these patients. In addition to total occlusion of the left main coronary artery, three patients also had severe lesions of right coronary artery. Prior myocardial infarction history and significantly depressed left ventricle functions were detected in all three patients with right coronary artery lesions. Five patients were operated on cardiopulmonary bypass while two patients were operated off pump. All patients received alternating antegrade/retrograde cardioplegia for myocardial preservation. In patients with simultaneous right coronary artery disease we first established the origin of the collaterals to the left coronary system. For patients with collaterals arising from the right coronary artery segment distal to the right coronary artery lesion, the antegrade component was administered through the saphenous vein graft bypassed to a distal part of right coronary artery segment. Thus we have achieved a more effective distribution of the antegrade cardioplegia. In off-pump-operated patients the left coronary system was revascularized before the right coronary system. Postoperative low cardiac output syndrome occurred in only one patient who was operated off pump. There was no operative and early mortality. Mean follow-up was 32 +/- 21.42 (range, 4 to 60) months. Alternating antegrade/retrograde cardioplegia was used with acceptable results in patients with total occlusion of the left main coronary artery. In patients with simultaneous RCA lesion we recommend regulation of the antegrade component based on the origin of collaterals that supplies the left coronary system. In off-pump-operated patients we suggest avoiding of clamping of right coronary artery at the beginning of the operation while it still supplies all the coronary circulation.

Adult↗
PubMedDate not supplied

Reversed-J inferior versus full median sternotomy: which is better for awake coronary bypass surgery.

BACKGROUND: The aim of this study was to ascertain whether the approach with a less invasive reversed-J inferior sternotomy could improve intraoperative patient compliance and postoperative recovery than the standard median sternotomy. METHODS: Seventeen patients underwent elective single coronary artery bypass graft operation under high thoracic epidural anesthesia without endotracheal intubation. The reversed-J sternotomy was performed in 10 patients (Group A) and full sternotomy in 7 patients (Group B). The technical and surgical difficulties, pulmonary functions (by spirometric tests) and hospital stay were assessed. RESULTS: Through the reversed-J sternotomy coronary revascularization was accomplished without any additional technical difficulties and with a good exposure of both the left anterior descending artery and the left internal thoracic artery. No conversion to standard sternotomy and no intubation were observed. Additional doses of local anesthetic at jugular notch was not required in Group A. Pleura was opened more in Group B (57% vs. 20%; p = 0.14). Oxygen saturation was better in Group A during the surgical procedure (98.8 +/- 0.7% vs. 97.1 +/- 2.1%; p = 0.033), however, intraoperative PaCO2 was similar in both the groups. The patients in Group A were discharged from the hospital earlier (3.2 +/- 1.5 vs. 7.3 +/- 3.5 days; p = 0.004). CONCLUSIONS: Less invasive approach to coronary artery bypass graft operations is possible through combination of the high thoracic epidural anesthesia and a reversed-J sternotomy. This technique is less traumatic for patient and provides practical better oxygenation and shorter hospital stay.

Adult↗
PubMedDate not supplied

Risk factors for requirement of permanent pacemaker implantation after aortic valve replacement.

BACKGROUND: The aim of this study was to evaluate the frequency of requirement for permanent pacing and related risk factors after aortic valve replacement. METHODS: Among 465 patients operated between 1994 and 2004, 19(4.1%) patients with a mean age 49.9 +/- 17.2 years required the implantation of a permanent pacemaker. Eleven of them were female (57.9%). The main indication was aortic stenosis (89.5%). Severe annular calcification was documented in 78.9% of them, and the aortic valve was bicuspid in 57.9%. RESULTS: Risk factors for permanent pacing after aortic valve replacement (AVR) identified by univariate analysis were female sex, hypertension, preoperative ejection fraction, aortic stenosis, annular calcification, bicuspid aorta, presence of right bundle branch block (RBBB) or left bundle branch block (LBBB), prolonged aortic cross-clamp and perfusion times, and preoperative use of calcium channel blockers. Multivariate analysis showed that female sex (p = 0.01, OR; 5.21, 95% CI: 1.48-18.34), annular calcification (p < 0.001, OR; 0.05, 95% CI: 0.01-0.24), bicuspid aortic valve (p = 0.02, OR; 0.24, 95% CI: 0.07-0.84), presence of RBBB (p = 0.009, OR; 0.03, 95% CI: 0.003-0.44) or LBBB (p = 0.01, OR; 0.13, 95% CI: 0.02-0.69), hypertension (p = 0.03, OR; 0.22, 95%CI: 0.05-0.89), and total perfusion time (p = 0.002, OR; 1.05, 95% CI: 1.01-1.08) were associated risk factors. CONCLUSION: Irreversible atrioventricular block requiring a permanent pacemaker implantation is an uncommon complication after AVR. Risk factors are annular calcification, bicuspid aorta, female sex, presence of RBBB or LBBB, prolonged total perfusion time, and hypertension.

Adult↗