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Mehmet Halit Andac

Publications and source records attributed to Mehmet Halit Andac.

7 recordsLinked to original sources
PubMed2006

Decrease of total antioxidant capacity during coronary artery bypass surgery.

OBJECTIVE: Cardiac surgery induces an oxidative stress, which may lead to impairment of cardiac function. In this study, we aimed to measure the changes of oxidative and antioxidative status of patients undergoing coronary artery bypass surgery (CABG). MATERIALS AND METHODS: We studied 79 patients who underwent CABG with and without cardiopulmonary bypass (CPB). Of the 79 patients, 39 had CPB and 40 did not. Blood samples were drawn before, during, and after the surgery. Antioxidant status was evaluated by measuring total antioxidant capacity (TAC), and oxidative status was evaluated by measuring total peroxide (TP) levels and oxidative stress index (OSI). RESULTS: TP and OSI levels increased, while TAC decreased progressively after the beginning of surgery, for all patients. There were negative correlations between TAC levels and aortic cross-clamping period and anastomosis time ( r = -0.553, p < 0.001 and r = -0.500, p < 0.001, respectively). In addition, there was a positive correlation between TAC and ejection fraction (r = 0.647, p < 0.001). CONCLUSIONS: During CABG, oxidant and OSI levels significantly increase and TAC significantly decreases. This situation is influenced by long CPB and anastomosis time, and also by low ventricular ejection fraction. We concluded that the patients who undergo CABG are exposed to potent oxidative stress that impairs their TAC. We speculate that supplementation with antioxidant vitamins such as vitamins C and E may be beneficial for patients undergoing CABG.

Antioxidants↗
PubMed2005

Coronary artery bypass surgery in high-risk patients.

BACKGROUND: In high-risk coronary artery bypass patients; off-pump versus on-pump surgical strategies still remain a matter of debate, regarding which method results in a lower incidence of perioperative mortality and morbidity. We describe our experience in the treatment of high-risk coronary artery patients and compare patients assigned to on-pump and off-pump surgery. METHODS: From March 2002 to July 2004, 86 patients with EuroSCOREs > 5 underwent myocardial revascularization with or without cardiopulmonary bypass. Patients were assigned to off-pump surgery (40) or on-pump surgery (46) based on coronary anatomy coupled with the likelihood of achieving complete revascularization. RESULTS: Those patients undergoing off-pump surgery had significantly poorer left ventricular function than those undergoing on-pump surgery (28.6 +/- 5.8% vs. 40.5 +/- 7.4%, respectively, p < 0.05) and also had higher Euroscore values (7.26 +/- 1.4 vs. 12.1 +/- 1.8, respectively, p < 0.05). Differences between the two groups were nonsignificant with regard to number of grafts per patient, mean duration of surgery, anesthesia and operating room time, length of stay intensive care unit (ICU) and rate of postoperative atrial fibrillation. CONCLUSION: Utilization of off-pump coronary artery bypass graft (CABG) does not confer significant clinical advantages in all high-risk patients. This review suggest that off-pump coronary revascularization may represent an alternative approach for treatment of patients with Euroscore > or = 10 and left ventricular function < or = 30%.

Journal Article↗
PubMed2005

Mini-dose pump-prime aprotinin inhibited enhanced fibrinolytic activity and reduced blood loss and transfusion requirements after coronary artery bypass surgery.

OBJECTIVES: Low-dose aprotinin in the pump during cardiopulmonary bypass (CPB) has been shown to improve postoperative hemostasis and platelet preservation. This investigation was undertaken to evaluate the effects of mini-dose pump prime only aprotinin (70 mg) on the hemostatic parameters and blood transfusion requirements in patients undergoing on-pump coronary artery bypass surgery (CABG). MATERIALS AND METHODS: We studied 86 patients who underwent CABG. Forty patients received mini-dose aprotinin (500.000 KIU [70 mg] in the pump), and a control group of 46 did not. D-dimer level, full blood count, postoperative blood loss, and transfusion requirements were analyzed before, after one hour operation and first day after operation. RESULTS: Twenty-four-hour postoperative blood loss was significantly reduced in the aprotinin group (188+/- 51.5 ml vs. 818+/- 243.5 ml, [mean +/- standard deviation] p < 0.01). Patients in the aprotinin group also received significantly less banked blood posoperatively than the control group (1.20 +/- 0.52 vs. 3.33 +/- 1.13 Units/per patient (p < 0.04). One hour after operation, and 24 hours after operation D-dimer level was significantly reduced in the aprotinin group (p < 0.008 and p < 0.017, respectively). CONCLUSIONS: Mini dose pump-prime aprotinin reduces postoperative blood loss, transfusion requirements and yet confers hemostatic improvement through reduced fibrinolysis in patients undergoing routine coronary artery bypass grafting.

Aged↗
PubMed2005

Coronary endarterectomy with beating heart in patients with diffuse atheromatous coronary artery disease and poor ventricular function: early and midterm results.

BACKGROUND: In this study, we retrospectively reviewed our experience with off-pump coronary artery bypass grafting and coronary artery endarterectomy in patients with severely reduced left ventricular function and diffuse atheromatous coronary artery disease to evaluate the early and midterm results. METHODS: Between July 1998 and March 2004, 42 patients underwent off-pump myocardial revascularization with coronary artery endarterectomy. The mean age (+/-SD) for the 28 male and 14 female patients was 59 +/- 10.2 years. Twenty-seven patients (64.2%) had experienced a previous myocardial infarction, and 11 (26.2%) had undergone an operation on an emergency basis. All patients had an ejection fraction of less than 30%. The left anterior descending coronary artery was the most endarterectomized vessel (75% of patients). RESULTS: There were 5 early deaths (11%). Twenty-five (67.6%) of the surviving patients were symptom free, and 8 were in Canadian Cardiovascular Society classes II to IV. The ejection fraction improved after the operation in the 30 patients (71.42%) who underwent echocardiographic control and coronary angiography. The 28.4-month patency rate of the endarterectomized coronary arteries was 89%. The patency rates were 93.3% for the left internal thoracic artery-left anterior descending coronary artery and 88.8% for the right coronary artery. CONCLUSION: The results of this study show increased operative mortality and morbidity in patients requiring coronary artery endarterectomy. However, the early results and particularly the midterm survival rates, clinical status, and continued graft patency justify off-pump coronary artery endarterectomy in patients with severely depressed left ventricular function and diffuse coronary artery disease. Many of these patients have disease that would otherwise be inoperable.

Adult↗
PubMed2005

Closure of secundum atrial septal defect with autologous right atrial patch: case report.

BACKGROUND: Although various synthetic materials and pericardium have been used for atrial septal defect (ASD) closure, investigators are continuing to search for an ideal material for this procedure. We report and evaluate a case in which autologous right atrial wall tissue was used for ASD closure. CASE: In this case, we closed a secundum ASD of a 22-year-old woman who also had right atrial enlargement due to the defect. After establishing standard bicaval cannulation and total cardiopulmonary bypass, we opened the right atrium with an oblique incision in a superior position to a standard incision. After examining the secundum ASD, we created a flap on the inferior rim of the atrial wall. A stay suture was stitched between the tip of the flap and the superior rim of the defect, and suturing was continued in a clockwise direction thereafter. Considering the size and shape of the defect, we incised the inferior attachment of the flap, and suturing was completed. Remnants of the flap on the inferior rim were resected, and the right atrium was closed in a similar fashion. RESULTS: During an echocardiographic examination, neither a residual shunt nor perigraft thrombosis was seen on the interatrial septum. The patient was discharged with complete recovery. CONCLUSION: Autologous right atrial patch is an ideal material for ASD closure, especially in patients having a large right atrium. A complete coaptation was achieved because of the muscular nature of the right atrial tissue and its thickness, which is a closer match to the atrial septum than other materials.

Adult↗
PubMed2003

How I do it: a novel method that provides simultaneous coronary artery occlusion and retraction for beating heart bypass surgery.

BACKGROUND: Coronary artery stabilization and retraction have been a crucial problem in beating heart bypass surgery. Conventional methods such as looping and suspension of the target artery carry risk of coronary artery damage. Above all, these methods do not aid in retraction in coronary arteriotomy. METHODS: Five mongrel dogs were used in this study. After intratracheal general anesthesia, median sternotomy was performed, and the left anterior descending coronary artery (LAD) and right coronary artery (RCA) were chosen as target vessels. To stabilize epicardium we passed the proximal portion of each coronary artery with a pledgeted suture parallel to the orientation of the coronary artery through the arteriotomy. After a similar suture was passed on the distal side, pledgets were placed on both sides of the incised coronary artery, and tourniquets were applied and snared just after opening of the target coronary artery for occlusion of proximal and distal flow. The tourniquets also were pulled up at an angle of 45 degrees on both sides for stabilization of the epicardium and retraction of the arteriotomy edges. RESULTS: All instances of snare-induced coronary occlusion and retraction were analyzed (10 coronary snares in 5 dogs, the RCA and the LAD of each dog being used). Flow in the coronary artery was stopped, and visualization of the arteriotomy was successful. CONCLUSIONS: We described a novel technique of temporary coronary artery stabilization and occlusion that provided simultaneous retraction in coronary arteriotomy. This procedure resulted in a clean and retracted operative field for suitable anastomosis even in the arteriotomy edges.

Animals↗