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Tayfun Aybek

Publications and source records attributed to Tayfun Aybek.

At least 19 recordsLinked to original sources

[Indication, technique, and results of aortic valve and ascending aorta reconstruction].

Aortic valve replacement is the standard procedure in patients with aortic valve regurgitation (AR). Although long-term results for both biological and mechanical heart valves could be improved, a valve-sparing operation has several advantages especially in young patients. Alterations in the geometry of the aortic root, especially dilatation of the sinutubular junction, are the primary cause of AR in patients with aneurysms of the ascending aorta. In patients with a bicuspid aortic valve, AR is usually caused by a prolapse; with appropriate surgical experience, the prolapse can be corrected and the valve reconstructed. Isolated reconstruction of a tricuspid aortic valve such as decalcification, commissurotomy or plication of ring or leaflets are seldom indicated. The recontstructive techniques for aortic root aneurysms or type A dissection described by David and Yacoub have become routine procedures over the last decade. The long-term clinical results are excellent, and revision and thromboembolism rates are very low. A maximal diameter of the aortic root > 5 cm is indicative for performing the above procedures. This technique has been used in the own clinic since 1996 with excellent clinical and echocardiographic results. Only four of 101 patients operated had a moderate AR during the follow-up period. The reconstruction of a prolapse in a bicuspid aortic valve is possible by using an autologous, fixed pericardial patch, with very good long-term results. By using this surgical technique, two geometrically correct pockets with a broad coaptation zone can be constructed. In 36 of the patients operated in the own clinic, only four patients showed grade I AR. No patient had to undergo reoperation. An aortic valve reconstruction for an isolated leaflet perforation following a healed endocarditis is seldom indicated.In the authors' opinion, valve-sparing reconstruction in cases of aneurysms of the ascending aorta, and for bicuspid valves, represents a promising alternative to prosthetic valve replacement. With low surgical mortality and morbidity, excellent clinical and functional long-term results can be achieved. Furthermore, the lack of the necessity of anticoagulation as well as positive hemodynamic factors argue for a valve-sparing surgical technique. A final evaluation of the method is not possible, however, until long-term follow-up of up to 20 years is available and the positive results have been confirmed.

Adult↗

Does totally endoscopic access for off-pump cardiac surgery influence the incidence of postoperative atrial fibrillation in coronary artery bypass grafting? A preliminary report.

BACKGROUND: The occurrence rate of atrial fibrillation (AF) after coronary artery bypass grafting, quoted in the literature, is wide ranging from 5% to over 40%. It is speculated that, off-pump coronary artery bypass grafting (OPCAB) and also minimally invasive cardiac surgery reduces the incidence of postoperative AF due to reduced trauma, ischemia, and inflammation. Current data, however, do not clearly answer the question, whether the incidence of postoperative AF is reduced in using minimally invasive techniques, ideally resulting in the combination of both small access and off-pump surgery. The aim of this study was to evaluate the incidence of postoperative AF in patients undergoing totally endoscopic off-pump coronary artery bypass grafting (TECAB). METHODS: A retrospective analysis of 72 patients undergoing myocardial revascularization was performed. Early postoperative incidence of AF was compared between three groups of patients: 24 after conventional coronary artery bypass grafting (CABG), 24 after OPCAB, and 24 after totally endoscopic off-pump CABG. Clinical profile of the patients, including factors having potential influence on postoperative AF was matched for groups. RESULTS: Postoperative AF occurred in 25% of the patients in the CABG group, in 16% of the patients in the OPCAB group, and in 16% of the patients in the TECAB group. This difference has no statistical significance. Risk factors and incidence of postoperative complications were comparable in all groups excepting the number of distal anastomoses. There was a statistical significance between CABG group and TECAB group. CONCLUSION: Avoiding cardiopulmonary bypass and minimizing surgical trauma did not reduce the incidence of postoperative AF in this patient collective. It remains an attractive hypothesis that postoperative AF is reduced by off-pump myocardial revascularisation and minimizing surgical trauma but more robust data are required.

Aged↗

Left ventricular remodeling impacts the function of the Quattro stentless mitral valve bioprosthesis (a 4-year experience).

OBJECTIVE: The St Jude Quattro stentless mitral valve prosthesis (QMV) is sutured to the mitral annulus and the papillary muscle heads, thereby preserving the subvalvular apparatus. After mitral valve replacement, remodeling of the left ventricle is often observed, causing a dilated ventricle to shrink in diameter. It was our objective to assess these changes in left ventricular (LV) geometry and evaluate its effects on the function of the QMV. METHODS: From September 1997 to October 2000, 24 patients received QMV at our institution. The patients were followed up at yearly intervals (mean 4.1 +/- 2.2 years). All pre- and postoperative echocardiograms were evaluated, with attention focused on the subvalvular apparatus, leaflet morphology, and occurrence of late mitral regurgitation. In addition, all clinical outcomes and valve-related complications were recorded. RESULTS: Forty-one percent of patients (10/24) developed late mitral regurgitation (mild, n = 5; moderate, n = 5). The site of regurgitation was located at the 2 commissures in all cases. In 8 patients, changes in LV diameter had occurred. The point of leaflet coaptation had shifted away from the annulus in 4 patients. The overall mortality was 12.3%, and the postoperative stroke rate was 12.3%. CONCLUSIONS: Midterm changes in LV geometry seem to affect the competence of the QMV. Predicting these changes and subsequently adapting the sizing procedure remain a challenging task. The high rate of late valve incompetence and poor clinical outcomes has prompted us to discontinue recruitment of patients for this trial.

Bioprosthesis↗

Two hundred forty minimally invasive mitral operations through right minithoracotomy.

BACKGROUND: This study reports of our 7-year experience with minimally invasive mitral valve operations using the transthoracic clamp technique, reviewing morbidity and mortality as well as echocardiographic follow-up results. METHODS: Between 1997 and 2004, 241 patients (121 male; aged 56 +/- 14 years) underwent minimally invasive mitral valve surgery through right thoracotomy using the transthoracic clamp technique. Reconstructions were done in 199 patients, and 42 valves were replaced. Mean length of incision was 7.0 +/- 1.2 cm. Mean preoperative New York Heart Association functional class was 2.6 +/- 0.9. RESULTS: Thirty-day mortality was 3.3% (n = 8). Operating, bypass, and cross-clamp times averaged 241 +/- 52, 142 +/- 40, and 84 +/- 26 minutes, respectively. Seven patients (2.9%) had conversion to sternotomy. Nine patients (3.7%) underwent reexploration for bleeding. Mean intensive care unit and hospital stay were 18 hours and 8.1 days, respectively. Mean follow-up was 30 +/- 18 months (range, 3 to 76). Echocardiographic follow-up documented persistently competent valve function in all but 6 patients who had grade III regurgitation. Five of them underwent mitral valve re-reconstruction and 1 underwent transplantation. At 76 months, freedom from nontrivial recurrent mitral regurgitation and reoperation were 92.3% and 96.2%, respectively. Actuarial survival at 76 months, including early mortality, was 90.7%. Thoracic wounds were free from infection in all patients. CONCLUSIONS: This study demonstrates that the direct vision, transthoracic clamp technique for minimally invasive mitral valve surgery is reproducible with low mortality and morbidity rates. It results in excellent cosmesis and abolished the risk of thoracic wound infection. Results are comparable to midterm outcomes of conventional operations.

Adolescent↗

Seven years' experience with suture annuloplasty for mitral valve repair.

OBJECTIVE: Our early experience with the mural annulus shortening suture procedure for mitral valve repair showed superior hemodynamic performance over ring annuloplasty. The aim of this study was to assess the durability of the mural annulus shortening suture procedure and evaluate our 7-year experience regarding valve function, hemodynamic performance, and clinical outcome. METHODS: Between 1996 and 2003, 222 elective consecutive patients (58.1% males; age, 59 +/- 14 years) underwent simple or complex mitral valve repair. Minimal invasive reconstruction was performed in 150 patients. For correction of annular dilatation, we used double-running 2-0 polytetrafluoroethylene sutures to reinforce the posterior circumference of the annulus. Patients were investigated prospectively by means of transthoracic echocardiography before discharge and 1 and 5 years after the operation. The mean follow up was 32 +/- 21 months (range 1-77 months). RESULTS: The operative mortality was 3.1%. Hemodynamic performance at 1 and 5 years showed low mean transvalvular gradients (2.1 +/- 0.9 and 2.0 +/- 0.8 mm Hg, respectively) and a calculated mitral valve orifice area of 3.3 +/- 0.9 cm2 and 3.1 +/- 0.6 cm2, respectively, with progressive annular dilatation from 31.2 +/- 3 mm to 33.9 +/- 4 mm at 1 year and 35.7 +/- 4 mm at 5 years (P < .01). Clinical status improved from New York Heart Association class 3.0 +/- 0.4 to 0.6 +/- 0.8 at 1 year and 0.8 +/- 0.8 at 5 years. Freedom form nontrivial residual mitral regurgitation was 82.3%, freedom from reoperation was 95.1% and actuarial survival was 87.2%, all at 77 months. CONCLUSIONS: The midterm results show satisfactory hemodynamic performance and clinical improvement. Valve competence and reoperation rates are comparable with those of other reports. Durability of the mural annulus shortening suture procedure for mitral valve repair is questioned because progressive annular redilatation occurs.

Female↗

The radial artery as a conduit for coronary artery bypass grafting: review of current knowledge.

The effect of coronary artery bypass grafting (CABG) lasts as long as the grafts are patent. The internal mammary artery has been considered the "golden" graft due to the superb long-term patency, exceeding 90% at 10 years. The saphenous vein grafts, unfortunately, tend to occlude with a rate of 10-15% within a year after surgery, and eventually, at 10 years after the operation, as much as 60-70% of these vein grafts are either occluded or have angiographic evidence of atherosclerosis. The search for another "arterial conduit", the radial artery, has intensified through the last 15 years in hope to provide a better graft than the saphenous vein for CABG. This article reviews the current knowledge for the radial artery as a conduit in CABG.

Coronary Artery Bypass↗

Disseminated Aspergillus fumigatus infection with consecutive mitral valve endocarditis in a lung transplant recipient.

Aspergillus infection is a known complication of lung transplantation and remains associated with high mortality rates. The manifestation of the infection varies from simple colonization of the lung to disseminated complicated infections. Early Aspergillus infection has been rarely observed in a small number of lung transplant recipients; most cases occur during the late post-operative period. The pulmonary involvement has often been described as the first clinical localization of the disease. Although other various forms of Aspergillus infection are not uncommonly encountered after lung transplantation, Aspergillus mitral valve endocarditis is rare. We present a case of disseminated Aspergillus fumigatus infection with consecutive mitral valve endocarditis having developed 78 days after double-lung transplantation for cystic fibrosis.

Adult↗

Echocardiographic assessment in minimally invasive mitral valve surgery.

BACKGROUND: Due to limited exposure, removal of intracavitary air and visual assessment of cardiac function during minimally invasive procedures are not always possible. We analysed the utility of intraoperative transesophageal echocardiography (TEE) and postoperative transthoracic echocardiographic (TTE) in minimally invasive mitral valve (MV) procedures. MATERIAL/METHODS: We evaluated data from 163 consecutive patients undergoing isolated minimally invasive MV replacement (n=40) or repair (n=123) via small right anterolateral thoracotomy (121 complex mitral procedures). Cardioplegic arrest was achieved using either endoaortic (n=23) or transthoracic aortic clamp (n=140). In addition to preoperative TTE, TEE was used intraoperatively before and after cardiopulmonary bypass (CPB). Postoperative TTE was performed to monitor valve function at 3 and 12 months, and at 5-year follow-up. RESULTS: Pre-CPB TEE was useful to assess valve dysfunction and assist in placement of the arterial and venous cannulas. During CPB, placement and positioning of the endoclamp were guided effectively in all but 4 patients, in whom recurrent balloon migration necessitated secondary transthoracic aortic clamping. TEE detected one acute retrograde aortic dissection and one circumflex artery occlusion. After 18.7+/-10.6 months follow-up, all patients except three improved symptomatically and had consistently good valve function. CONCLUSIONS: Intraoperative TEE is essential for minimally invasive MV surgery, because it allows immediate control of valve function before and after surgery. It is useful to detect unexpected complications requiring immediate remedy. Postoperative echocardiographic results show that minimally invasive MV surgery is a good alternative to conventional surgery even in complex MV repairs.

Adolescent↗

Minimally invasive port access versus conventional mitral valve surgery: prospective randomized study.

BACKGROUND: We compared the port access mitral valve surgery with the conventional procedure through median sternotomy in a prospective randomized study. METHODS: Forty elective patients with mitral valve disease were prospectively randomized to undergo minimally invasive (group I) or conventional (group II) mitral valve operation. The patients of group I had limited access through right small anterior thoracotomy and a femorofemoral cardiopulmonary bypass system using the endoclamp technique. To assess the efficiency and safety of the procedure, intraoperative and postoperative clinical data and markers of myocardial, cerebral, and lower limb ischemia were collected. Pulmonary function tests were performed to compare the preservation of pulmonary function. Neuropsychological tests were conducted for quantification of neurological and cognitive disorders. RESULTS: Mitral valve reconstructions were performed in 28 patients (70%) in both groups. Intraoperative procedure-associated problems were experienced in 9 patients (45%) in group I, and 6 of them (30%) had to be converted to direct transthoracic aortic clamping. Markers of myocardial and cerebral damage as well as pulmonary and neuropsychological tests did not show statistically significant difference between groups. CONCLUSIONS: The minimally invasive port access technique for mitral valve surgery can be done with similar clinical safety as procedures through median sternotomy. The problems with endoclamping have forced us to change our practice to the more simple and economic transthoracic aortic clamping technique.

Cardiopulmonary Bypass↗

Comparison of three anesthetic techniques for off-pump coronary artery bypass grafting: general anesthesia, combined general and high thoracic epidural anesthesia, or high thoracic epidural anesthesia alone.

OBJECTIVE: This study compared general anesthesia (GA), combined GA plus thoracic epidural anesthesia (TEA), and TEA alone in patients scheduled for off-pump coronary artery bypass grafting. DESIGN: Prospective, nonrandomized clinical study SETTING: University hospital. PARTICIPANTS: Ninety consenting patients undergoing beating-heart coronary artery revascularization with comparable coronary status and left ventricular function. INTERVENTIONS: GA (n=30) was conducted with propofol, remifentanil, and cisatracurium or combined with TEA (GA+TEA, n=30) or TEA as the sole anesthetic with ropivacaine plus sufentanil (TEA, n=30). MEASUREMENTS AND MAIN RESULTS: Groups were comparable regarding the surgical approaches and the number of anastomoses. Four patients (GA, n=2; GA+TEA, n=2) who required unplanned cardiopulmonary bypass, and 4 patients in the TEA group who underwent unexpected intubation because of pneumothorax (n=2), phrenic nerve palsy, or incomplete analgesia were excluded from further analysis. Intraoperative heart rate decreased significantly with both GA+TEA and TEA. None of the patients with TEA alone was admitted to the intensive care unit, they all were monitored on average for 6 hours postoperatively in the intermediate care unit and allowed to eat and drink as desired on admission. Postoperative pain scores were lower in both groups with TEA. There were no differences among groups in patients overall satisfaction. CONCLUSION: Based on the authors data, all anesthetic techniques were equally safe from the clinicians standpoint. However, GA+TEA appeared to be most comprehensive, allowing for revascularization of any coronary artery, providing good hemodynamic stability and reliable postoperative pain relief. Nonetheless, the actual and potential risks of TEA during cardiac surgery should not be underestimated.

Aged↗

Closure of atrial and ventricular septal defects should be performed by the surgeon.

Surgeons look back on 57 years of experience in the closure of atrial septal defects (ASDs) and 46 years in the closure of ventricular septal defects (VSDs). The transcatheter approaches to repair ASDs started first in the 1980s and for VSDs 8 years later. This study sought to reveal the surgical features only given by the surgical therapy and the limitation of interventional ASD and VSD closure. A variety of surgical techniques including the minimal invasive techniques for ASD or VSD closure are well described in recent publication with good results. The surgical trend is to improve the cosmetic outcome by minimizing the size of skin incision. The latest robotically assisted technique requires only four stab wound incisions. New techniques and devices have revolutionized the transcatheter technique but could not achieve the surgical ability to close all types of ASD or VSD, control arrhythmias, and correct additional valve disease or malformation. The mortality for interventional and surgical procedures approaches zero in recent publication. The residual shunting after surgical closure of ASD varies from 2% to 7.8% versus 5% to 33% after interventional closure. General complications caused by the surgical procedure are negligible; however, the shortness of hospital stay and the cosmetic appeal is an advantage of interventional ASD closure. There is no scientific comparison of surgical vs. interventional VSD closure yet.

Cardiac Catheterization↗

Valve opening and closing dynamics after different aortic valve-sparing operations.

BACKGROUND AND AIM OF THE STUDY: Aortic valve resuspension for ascending aortic aneurysm repair is associated with removal of the sinus of Valsalva. This may cause changes in leaflet motion and thus impact on long-term durability. The opening and closing characteristics of the aortic valve leaflets after reimplantation were studied using a published technique and a modification to create a 'neosinus', and the results compared to those of an age-matched control group. METHODS: Between September 1995 and March 2002, 25 patients underwent normal aortic root reconstruction (group A), while in a further 21 patients the modified neosinus technique was used (group B). In both groups, the native valve was preserved and suspended inside a tubular prosthesis, with reimplantation of the coronary arteries. Transthoracic and transesophageal studies of aortic valve dynamics were performed intraoperatively, before hospital discharge, and at one year after surgery in all patients; the data were compared with those from a separate group of 25 matched control individuals (group C). RESULTS: The valve opening velocity was 61.3+/-20.1, 46.3+/-8 and 29.2+/-9.8 cm/s in groups A, B and C, respectively (group A versus B, p = 0.003; A versus C, p <0.0001; B versus C, p <0.0001). Closing velocity was increased to 57.5+/-23 and 43.8+/-7 cm/s in groups A and B, compared to 23.6+/-7 cm/s in group C (A versus B, p = 0.012; A versus C, p <0.0001; B versus C, p = 0.0002). In seven group A patients, the leaflets touched the prosthetic wall during systole. Slow systolic closing displacement (SCD) amounted to 7.3+/-6 % of maximal opening in group A and 12.6+/-5 % in group B (p = 0.05), compared to 21.1+/-8.3% in group C (group A versus group C, p <0.0001; B versus C, p = 0.002). CONCLUSION: Reimplantation of the natural aortic valve in a prosthetic graft causes abnormally high opening and closing speeds, with possibly increased stress. The study results showed lower valve opening and closure dynamics after the creation of a sinus bulge compared to the conventional reimplantation technique. However, mid-term clinical observations showed favorable valve competence for both types of repair. Further long-term follow up is necessary to prove whether more physiological leaflet dynamics lead to improved durability.

Adolescent↗

[Robotic coronary artery surgery: past, present and future].

Minimally invasive endoscopic procedures in cardiac surgery have only become possible since the introduction of telemanipulator systems. In this study we review robotic assisted telemanipulation systems and procedures on beating and arrested heart for total endoscopic revascularization. Robotic surgery is still under development. The most important factors limiting this new technique are high costs and the fact that only selected patients are able to be operated on. But studies on technology especially to improve anastomotic techniques are going on to produce an alternative for coronary revascularisation. We did not yet hit all goals but the future seems promising.

Cardiovascular Surgical Procedures↗

Current status of robotically assisted coronary revascularization.

This article reviews the current status of totally endoscopic coronary revascularization using telemanipulation systems for robotic assistance. Current challenges in implementing a robotic surgical program are discussed, and application of the technology in both arrested and beating heart procedures is considered.

Cardiac Surgical Procedures↗

Coronary artery bypass grafting via sternotomy in conscious patients.

The application of high thoracic epidural anesthesia (TEA) as an adjunct to general anesthesia is increasingly being used for coronary artery bypass grafting (CABG) with extracorporeal circulation. Recent developments in beating heart techniques rendered the sole use of TEA in conscious patients possible, and have been reported for single-vessel beating heart CABG via lateral thoracotomy. For multi-vessel revascularization, the heart is usually approached via sternotomy; therefore, the sole use of TEA was applied in awake patients who underwent CABG via sternotomy. A total of 7 patients scheduled for awake coronary artery bypass grafting (ACAB) received TEA via an epidural catheter placed at the levels of T1-2 or T2-3, respectively. Total arterial myocardial revascularization was performed after partial lower sternotomy. Besides standard monitoring, anesthetic levels were determined using an epidural scoring scale for arm movements (ESSAM). While 6 patients were awake and spontaneously breathing during the entire procedure, one patient had to be intubated intraoperatively because of respiratory distress caused by phrenic nerve palsy. Hemodynamics were stable throughout the operation. No significant arterial hypercarbia occurred. All patients rated TEA as "good" or "excellent." We could demonstrate that the single use of TEA for CABG via sternotomy was feasible and that the patients felt well, were painfree, and remained hemodynamically stable. High patient satisfaction in our small and highly selected cohort can be reported. Because beating heart surgery in a conscious patient still carries a significant risk, further randomized controlled trials are mandatory to definitively evaluate the role of sole TEA in cardiac surgery.

Aged↗

Awake coronary artery bypass grafting: utopia or reality?

BACKGROUND: Off-pump coronary artery bypass grafting (OPCAB) was implemented to reduce trauma during surgical coronary revascularization. High thoracic epidural anesthesia further reduced intraoperative stress and postoperative pain. This technique also supports awake coronary artery bypass (ACAB), completely avoiding the drawbacks of mechanical ventilation and general anesthesia in high-risk patients. We compared our first results of the ACAB procedure with the conventional OPCAB operation. METHODS: Thirty-five patients underwent ACAB (group A) with left internal mammary artery to left anterior descending coronary artery grafting using a partial lower ministernotomy (n = 25) or double bypass grafting (n = 9) and even triple vessel coronary artery revascularization (n = 1) through complete median sternotomy. Thirty-four patients (group B), matched for age, sex, and comorbidity with group A, underwent either partial lower ministernotomy (n = 24) or OPCAB by complete sternotomy (n = 10). We recorded clinical outcomes and postoperative visual analog scale pain scores. RESULTS: In group A, 32 patients remained awake throughout the entire procedure. Three patients required secondary intubation because of incomplete analgesia (n = 1) or pneumothorax (n = 2). Patients in group A had a recovery room stay of 6.0 +/- 3.2 hours. In group B, mechanical ventilation was implemented for 4.8 +/- 3.1 hours and intensive care unit stay lasted 12 +/- 6.8 hours. Group A had no in-hospital deaths, compared with 1 death in the conventional OPCAB group. Each group had 1 patient with graft stenosis detected on the predischarge angiogram. Early postoperative pain was significantly less in group A than in group B (visual analog scale of 32 +/- 8 compared with 58 +/- 11, p < 0.0001). CONCLUSIONS: The present data demonstrate the feasibility and safety of surgical coronary revascularization without general anesthesia. Continuation of thoracic epidural analgesia provides better pain control and faster mobilization after such procedures. Surprisingly, the ACAB procedure was well accepted by the patients.

Anesthesia, Epidural↗

Operative techniques in awake coronary artery bypass grafting.

BACKGROUND: Off-pump coronary artery bypass grafting was implemented to reduce trauma of surgical coronary revascularization by avoiding extracorporeal circulation. High thoracic epidural anesthesia further reduces intraoperative stress and postoperative pain. In addition, this technique even allows awake coronary artery bypass grafting, avoiding the drawbacks of mechanical ventilation and general anesthesia in high-risk patients. METHODS: Thirty-four patients underwent awake coronary artery bypass grafting with left internal thoracic artery to left anterior descending coronary artery by partial lower ministernotomy (n = 20), H-graft technique (n = 2), or rib cage-lifting technique (n = 2). In 9 cases we performed double bypass grafting, and in 1 case we performed triple-vessel coronary artery revascularization through complete median sternotomy. In addition to clinical outcomes, visual analog scale pain scores were recorded on days 1, 2, and 3 after surgery. RESULTS: Thirty-one patients remained awake throughout the whole procedure. Three patients required secondary intubation because of incomplete analgesia (n = 1) or pneumothorax (n = 2). Procedure time was 90 +/- 31 minutes, and recovery room stay was 4.2 +/- 0.6 hours. There were no in-hospital deaths or serious postoperative complications. In 1 case a graft occlusion was documented on predischarge angiography. Early postoperative pain was low (visual analog scale score of 30 +/- 6). CONCLUSION: These data demonstrate the feasibility and safety of various surgical coronary revascularization techniques without general anesthesia. Continuation of thoracic epidural analgesia provides good pain control and fast mobilization postoperatively. Surprisingly, the awake coronary artery bypass grafting procedure was well accepted by the patients.

Aged↗