Biomedical subjects

Mehmet Erdem Toker

Publications and source records attributed to Mehmet Erdem Toker.

11 recordsLinked to original sources

PubMed2006

Combined approach to a peripheral congenital arteriovenous malformation: surgery and embolization.

A 28-year-old woman with a complex peripheral congenital arteriovenous malformation in the left shoulder and left upper arm was treated by a combination of surgery and embolization. In the consecutive four operations, the major feeding arteries of the arteriovenous malformation were ligated, but as her complaints increased, transcatheter embolization was planned for releaving the symptoms in the first aspect. A total of eight embolization sessions were performed with Onyx during the 3-year period. The arteriovenous communications were occluded by embolization, with approximately more than an 80% decrease in the lesion size angiographically. After these interventions, the patient's symptoms improved clinically and dyspnea was lessened. Peripheral congenital arteriovenous malformation is a rare and therapeutically challenging condition in which a combination of surgery and embolization would be necessary to obtain a good result.

Adult↗

PubMed2006

Multivariate analysis for operative mortality in obstructive prosthetic valve dysfunction due to pannus and thrombus formation.

The objective of the present study was to investigate the risk factors for early hospital mortality in reoperations performed for obstructive prosthetic valve dysfunction. Between January 1994 and April 2005, 63 patients underwent reoperation for obstructive prosthetic valve dysfunction. The mean age of the patients was 40.3 +/- 12.8 years. The mitral valve was replaced in 47 (74.6%) patients, the aortic valve in 6 (9.5%) patients, and both valves in 10 (15.9%) patients. Forty-three (68.2%) patients underwent emergency reoperations. Early hospital mortality occurred in 13 (20.6%) patients. The ethiology of the valve dysfunction was pannus formation in 45 (71.4%) patients and thrombus formation in 18 (28.6%). Pannus and thrombus were localized at the atrial side of the prosthetic valve in 15 (23.9%) patients, at the ventricular side in 13 (20.6%), and at both sides in 35 (55.5%). Inadequate anticoagulation was diagnosed in 28 of 63 (44.4%) patients. The mean INR level in these 28 patients was 1.43 +/- 0.24. In multivariate analysis, the only risk factor for early hospital mortality was left ventricular ejection fraction (P = 0.015; Odds: 0.000, 95% CI: 0.000-0.043). It is concluded reoperations for prosthetic valve dysfunction have a high mortality rate. This study revealed that left ventricular dysfunction is the major determinant of surgical mortality in patients requiring reoperation for valve dysfunction due to pannus or thrombus.

Adolescent↗

PubMed2006

Pedicled right internal mammary artery for reoperative off-pump revascularization of left anterior descending coronary artery.

In situ right internal mammary artery is the graft of choice in reoperative off-pump coronary artery bypass grafting, as well as in primary on-pump coronary artery bypass grafting, unless the vessel has been used previously. However, there are not enough data about postoperative angiographic findings of the in situ right internal mammary artery in reoperative coronary artery bypass grafting with the off-pump technique. From September 1993 through January 2004, we reviewed the postoperative course and the graft patency of 12 selected patients who underwent off-pump coronary artery bypass grafting reoperation only for revascularization of the left anterior descending artery, by means of a pedicled right internal mammary artery graft. All patients were evaluated clinically and by postoperative coronary angiography. There were no early or late deaths during the mean follow-up period of 33.08 +/- 30.05 months (range, 1-77 months). The mean interval from the 1st operation to the 2nd operation was 74.1 +/- 57.01 months (range, 4.5-171 months). Postoperative coronary angiograms of all patients showed a 100% patency rate for both in situ grafts and composite grafts. We suggest that use of the in situ right internal mammary artery in off-pump coronary artery bypass grafting is a safe and reliable option for revascularizing the left anterior descending artery, especially in reoperation.

Adult↗

PubMed2005

Operative mortality after valvular reoperations.

BACKGROUND: To determine the incidence and risk factors of mortality and morbidity in valvular reoperations. METHODS: Between January 1993 and December 2003, 309 valvular reoperations were performed. The reasons for reoperations were reconstructive surgery in first operation (110 patients, 35.5%), prosthetic valve endocarditis (12 patients, 3.8%), periprosthetic leakage (32 patients, 10.3%), new valve degenerations (12 patients, 3.8%), bioprosthetic dysfunction (92 patients, 29.7%), acute thrombotic stuck valve (30 patients, 9.7%), and pannus formation (21 patients, 6.7%). Mitral valves were replaced in 235 patients, aortic valves were replaced in 32 patients, 24 patients had aortic and mitral valve replacements, 2 patients had mitral and tricuspid valve replacements, and reconstruction of periprosthetic leakage was held in 16 patients. 264 patients had elective surgery, whereas 45 were operated on emergency basis. RESULTS: Hospital mortality was 14.23%. Mortality rate was found to be 10.6% for elective cases and 35.5% for emergency cases. Permanent pacemaker was required in 12 patients, 3 patients had cerebrovascular events, and mediastinitis was observed in 1 patient. Multivariate analysis demonstrated that age > 60 (P = .006; OR 7.3, 95% CI 1.7-30.1), emergency surgery (P = .001; OR 8.1, 95% CI 2.4-27.7), preoperative cerebrovascular accident (P = .003; OR 11.8, 95% CI 2.458.7), and concomitant ascending aorta replacement (P < .001; OR 27.4, 95% CI 6-127) were independent risk factors. CONCLUSION: Valvular reoperations can be carried out with acceptable morbidity and mortality in elective operations but mortality rates are still very high in emergent cases.

Adult↗

PubMed2005

Using the bilateral internal mammary artery in the left or right coronary artery system: 5-year comparison of operation techniques and angiographic results.

OBJECTIVE: Using the bilateral internal mammary artery (IMA) in coronary artery bypass grafting (CABG) surgery has prolonged survival, improved functional capacity, and reduced the rate of reintervention without increasing postoperative early morbidity and mortality. METHODS: Between January 1996 and December 1997, 94 CABG operations were performed using the bilateral IMA. In Group A (n = 45), the right IMA was anastomosed to the left coronary artery system; in Group B (n = 49), the right IMA was anastomosed to the right coronary artery system. The left IMA was always anastomosed to the left coronary artery system in both groups. RESULTS: There was 1 death (Group A) (1.06%), and 1 late death (Group B) (1.07%). One patient in Group A underwent balloon angioplasty, and 1 patient in Group B underwent reoperation after the follow-up. Pre- and postoperative data were similar between both groups, except for off-pump CABG, which was higher in Group B (2.2% versus 36.7%; P <.001). Twenty-three randomized patients in each group underwent control angiography until May 2002. Angiographic results showed that the patency of the right IMA to the right or left coronary artery system was similar (78.26% versus 82.6%; P = .7). But the left IMA had a better patency rate than the right IMA (95.65% versus 80.43%; P = .02). The patency rates of the left and right IMA anastomosis on the beating heart in Group B were not significantly different (92.3% versus 76.9%; P = .27). The patency of right IMA anastomosis with or without off-pump technique in Group B was similar (76.9% versus 80%; P = .84). CONCLUSIONS: Bilateral IMA can be used with low morbidity and mortality. The angiographic and clinical results of off-pump CABG show that bilateral IMA can also be used in off-pump surgery with similar results.

Adult↗

PubMed2005

Simultaneous Carotid Endarterectomy and Coronary Revascularization is Safe Using Either On-Pump or Off-Pump Technique.

The appropriate surgical strategy for patients with combined carotid and coronary artery disease remains controversial. We retrospectively compared our surgical results for 2 types of approaches in this disorder. The records of 76 patients consecutively operated on for carotid and coronary artery disease between August 1993 and October 2004 were reviewed. There were 18 males (66.6%) and 9 females (33.3%) in group I. Group II consisted of 35 males (71.4%) and 14 females (28.5%). The patients were divided into two groups: patients with combined off-pump coronary artery bypass and carotid endarterectomy (group I, n = 27), and those with one-stage on-pump coronary artery bypass and carotid endarterectomy (group II, n = 49). Surgical mortality and morbidity and late outcome were compared among the two groups. The average number of grafts was 1.2 +/- 0.4, with the average operative time of 3.3 +/- 0.3 hours in group I, and 2.3 +/- 0.5 grafts with operative time of 4.6 +/- 0.4 hours in group II (P < 0.001 and P < 0.001, respectively). There was 1 death (3.7%) in group I and 2 deaths (4.8%) in group II (P = 0.937). No patient from either group I or group II had postoperative stroke. Mean hospital stay was 7.4 +/- 1.9 days in group I and 11.3 +/- 1.7 days in group II (P < 0.001). At a mean follow-up of 5.5 +/- 3.3 years in group I, 1 patient had contralateral carotid endarterectomy (3.7%). Group II had a mean follow-up of 5.2 +/- 3.0 years and contralateral carotid endarterectomy was performed in 1 patient (2.0%). There were no late strokes or deaths in either group. Combined coronary artery bypass grafting and carotid endarterectomy using 2 different types of technique is a safe and effective procedure in patients with significant concomitant monolateral carotid and coronary artery disease.

Cardiac Surgical Procedures↗

PubMed2005

Double-patch repair of postinfarction ventricular septal defect.

We report 4 consecutive cases in which the double-patch technique was used to repair an inferior postinfarction ventricular septal rupture. The ventricular septal perforation was closed directly by stitching, with the same sutures, 2 autologous pericardial patches onto both sides of the affected septum, through only a left ventriculotomy. Complete closure of the defect was accomplished, and no residual shunt was observed in any patient. This technique appears to be useful in selected cases, such as ventricular septal perforation with myocardial infarction in the subacute or chronic phase, especially in instances of inferoposterior infarction. Further experience is needed to verify its safety and efficacy.

Cardiac Surgical Procedures↗

PubMed2005

Surgical treatment of aortobronchial and aortoesophageal fistulae due to thoracic aortic aneurysm.

We present a review of our single-institution experience, over 19 years, with aortobronchial and aortoesophageal fistulae due to descending thoracic aortic aneurysm. We conducted a retrospective chart review of 10 cases involving surgery for aortobronchial and aortoesophageal fistulae in our clinic from February 1985 through October 2004. Pathologic or predisposing conditions associated with aortobronchial fistula were descending thoracic aortic aneurysm (n=8), previous aortic surgery (n=1), and concomitant aortoesophageal fistula (n=1). Three patients presented emergently with aortobronchial fistula (n=2) and aortoesophageal fistula (n=1). Ages of the 10 patients ranged from 42 to 74 years (median, 63 years). The median cross-clamp time was 34 minutes (range, 27-41 min). Repairs, in 9 patients, involved an inlay of prosthetic tube graft using the clamp-and-sew technique, and in 1 patient repair involved patch aortoplasty. The operative mortality rate was 20%:1 patient had acute concomitant aortoesophageal and aortobronchial fistulae, and another had chronic aortobronchial fistula. There was no embolic stroke or paraplegia. During follow-up (median, 2.5 years), there were no deaths or postoperative morbidity We conclude that repair of aortobronchial and aortoesophageal fistulae using the clamp-and-sew technique can be performed with acceptable operative mortality and long-term results. However, the mortality rate continues to be highly significant in patients with acute bleeding aortobronchial fistula or with aortoesophageal fistula, despite rapid surgical intervention.

Adult↗

PubMed2003

Mitral clefts and interatrial septum defects: 15-year results.

Between 1985 and 2002, 60 patients (58% female) with a mean age of 20.3 +/- 12.1 years (range, 2-55 years) were treated for anterior mitral leaflet cleft. There was a primum atrial septal defect in 52 patients (87%) and a secundum type in 8 (13%). Concomitant cardiac defects were patent foramen ovale in 6 patients, cleft tricuspid valve in 3, ventricular septal defect in 2, cor triatriatum in 1, and persistent left superior vena cava in 1. Mean grade (1-4) of mitral insufficiency was 2.28 +/- 0.74. Atrial septal defects were closed with a pericardial patch in 45 patients, with a prosthetic patch in 11, and primarily in 4. Mitral leaflet clefts were repaired using interrupted sutures. There was no early or late mortality. Two patients (3%) needed a permanent pacemaker. Postoperatively, severe (> or =grade 3) mitral insufficiency developed in 2 patients; valve replacement was performed in one, cleft recurrence and leakage from the patch were treated in the other. Freedom from reoperation was 92.2% +/- 5.6% at 15 years. Surgical intervention can be performed for congenital anterior mitral leaflet cleft and interatrial septal defect with good results in both pediatric and adult age groups.

Adolescent↗

PubMed2002

Early- and long-term comparison of the on- and off-pump bypass surgery in patients with left ventricular dysfunction.

OBJECTIVE: The adverse effects of extracorporeal circulation increase the morbidity and mortality risk of coronary bypass surgery, especially in patients with left ventricular dysfunction. The purpose of this study was to provide a comparison of the early and long-term outcome between patient groups with left ventricular dysfunction (LVEF<40% or LVPS>or=15) operated with or without using cardiopulmonary bypass. METHODS: Fifty-one patients with left ventricular dysfunction, who were operated on between October 1992 and March 1994, were investigated retrospectively. They were divided into two groups: BH-group included 26 patients and cardiopulmonary bypass group had 25 patients. Mean age and risk factors were identical. All patients received one vessel bypass left internal mammary artery to left descending artery. RESULTS: There was no early mortality and perioperative myocardial infarction in either group. In the early postoperative period the need of cardiac support therapy was significantly higher in the cardiopulmonary-bypass group than in the beating heart-group: 32% versus 7.7% (p<0.05). The need for blood products (for fresh frozen plasma 3.63 +/- 2.15u versus 2.5 +/- 1.34u; p = 0.023; for packed red blood cells 1.8 +/- 0.75u versus 1.25 +/- 0.46u; p = 0.048), the extubation time (18.2 +/- 5.5 hours versus 15.3 +/- 3.8 hours; p = 0.03) and the hospital stay (10.64 +/- 3.2 days versus 7.92 +/- 2.25 days; p = 0.001) were higher in the cardiopulmonary bypass -group than in the beating heart-group. Actuarial survival for the beating heart-group was 92.3 +/- 5.2% at 6 years, and for the cardiopulmonary bypass group was 92 +/- 5.4% at 6 years (p = 0.67). CONCLUSIONS: In spite of more than four times as many patients in the cardiopulmonary bypass group requiring inotropic support after surgery, survival and cardiac death rates were similar for both groups. Off-pump bypass surgery conserves the blood constituents. The benefits of both techniques to improve the left ventricular performance score and ejection fraction were similar, but postoperative extubation time, length of intensive care unit and hospital stay were reduced significantly in the beating heart group. With these good results of the beating heart coronary bypass surgery and considering its cost effectiveness, we concluded that coronary bypass on a beating heart can be an alternative to cardiopulmonary bypass technique in selective patient groups.

Adult↗

PubMedDate not supplied

Does aortic root enlargement impair the outcome of patients with small aortic root?

BACKGROUND: Posterior root enlargement procedures provide the implantation of suitable-sized prosthetic valves in patients with a small aortic root to prevent a high postoperative transvalvular gradient. The aim of this study was to evaluate long-term results of the posterior root enlargement. METHODS: Between 1985 and 2002, 124 patients underwent aortic valve replacement with a posterior root enlargement. The main indication was a small aortic valve orifice area to patient body surface area (indexed valve area < 0.85 cm2/m2). Fifty-four (44%) patients were male, and 70 (56%) were female with a mean age 39.1 +/- 14.3 years. Indications for operation were severe calcified aortic valve stenosis (37.1%), severe aortic insufficiency (25.8%), or combination (37.1%). Seventy-five (60%) patients received double-valve replacement. A pericardial patch was used in 100 patients (80.6%) and a Dacron patch was used in 24 patients. RESULTS: Operative mortality was 6.4% (8 patients). The causes of hospital mortality were low cardiac output syndrome (LCOS) (in 6 patients), cerebrovascular events (in 1 patient) and multiple organ failure (in 1 patient). Multivariate analysis demonstrated concomitant coronary revascularization to be a significant (p = 0.03) predictor for early mortality. There were six (5.4%) late deaths. Cox proportional hazards regression analysis demonstrated LCOS (p = 0.013) and infective endocarditis (p = 0.003) to be significant predictors for late mortality. Atrioventricular block required a permanent pacemaker was observed in 4 patients (3.2%). CONCLUSIONS: Posterior aortic root enlargement techniques can be easily applied without additional risks. Long-term survival and freedoms from valve-related complications are satisfactory.

Adolescent↗