Sems Malte Tugtekin

Interleukin-1, interleukin-6 and myocardial enzyme response after coronary artery bypass grafting – a prospective randomized comparison of the conventional and three minimally invasive surgical techniques

OBJECTIVE In order to evaluate the traumatic effects of median sternotomy and cardiopulmonary bypass (CPB) in conventional and minimally invasive coronary artery bypass grafting, inflammatory response was studied in a prospective randomized trial in patients referred to single-vessel coronary artery bypass grafting. METHODS Four surgical techniques were compared: group 1, median sternotomy with CPB in ten patients (eight male, two female; aged 59.6+/-11.0 years (mean+/-SD)); group 2, median sternotomy and off-pump in ten patients (seven male, three female; aged 65.1+/-10.0 years); group 3, minithoracotomy with CPB in ten patients (seven male, three female, aged 61.2+/-10.4 years); group 4, minithoracotomy and off-pump in ten patients (nine male, one female, aged 62.9+/-9.8 years). All patients received a left internal mammary artery graft to the left anterior descending artery (LAD). Clinical data, perioperative values of cytokines and cardiac enzymes were monitored. RESULTS There were no major complications. Troponin-T and creatine kinase isoenzyme MB (CK-MB) levels were significantly higher in CPB procedures (P<0.0056; multivariate general linear model). Interleukin-6 (IL-6) levels were significantly higher in minithoracotomy procedures. Interleukin-1 (IL-1) was significantly increased in all patients compared with the preoperative values. CONCLUSIONS The use of CPB is combined with higher levels of troponin-T and CK-MB as signs of myocardial damage. Surgical access was identified as a trigger of inflammatory response, as minithoracotomy is related to higher levels of IL-6. IL-1 increased in all procedures and this occurred independently of the surgical access or the use of CPB, which points out a potential relationship between inflammatory response and anesthesia. Neither CPB nor surgical access influenced the clinical outcome in the treatment of coronary artery single-vessel bypass grafting.

Pushing the limits—further evolutions of transcatheter valve procedures in the mitral position, including valve-in-valve, valve-in-ring, and valve-in-native-ring

OBJECTIVE Transcatheter heart valve (THV) procedures are constantly evolving. We report our experience with valve-in-valve, valve-in-ring, and direct-view valve-in-native-ring implantation in the mitral position. METHODS Fourteen patients undergoing THV implantation in the mitral position were included. Clinical and postoperative data, including echocardiography and further follow-up, were analyzed. RESULTS Ten valve-in-valve and 2 valve-in-ring procedures were successfully performed using the transapical access route. For the third valve-in-ring procedure we used an antegrade left-atrial access via right anterolateral minithoracotomy. In 1 patient surgical mitral valve replacement was planned. Intraoperatively, the annulus appeared severely calcified and regular implantation of a bioprosthesis was not possible. As a last resort, a 29-mm Sapien XT valve (Edwards Lifesciences Inc, Irvine, Calif) was implanted under direct view. The initial result was satisfactory, but on the first postoperative day relevant paravalvular regurgitation occurred. Subsequently, the valve was fixed to an atrial cuff by 1 running suture. In this series 27-, 29-, and 31-mm bioprostheses and 28- and 30-mm annuloplasty rings were treated with 26- or 29-mm Sapien XT valves. Postoperative echocardiography on day 10 and after 6 weeks revealed good prosthesis function in all cases. In 2 valve-in-valve patients who solely received anticoagulation therapy with acetylsalicylic acid, signs of beginning valve thrombosis occurred after 8 weeks and 3 months, respectively. During further course, valve function was normalized using warfarin therapy. CONCLUSIONS Our results demonstrate feasibility of valve-in-valve and valve-in-ring THV procedures in the mitral position. Permanent anticoagulation therapy with warfarin seems to be necessary to prevent valve dysfunction. THV implantation in a calcified native mitral ring for bailout seems not to be reproducible and thus cannot be recommended.

Transapical Transcatheter Valve-in-Valve Implantation for Deteriorated Mitral Valve Bioprostheses

BACKGROUND The transcatheter valve-in-valve concept has been described for patients requiring redo valve surgery. We report our experience with transapical mitral valve-in-valve implantation. METHODS Since 2008, 301 patients were treated with transapical transcatheter valve implantation. Seven of these patients presented with a deteriorated mitral valve bioprosthesis and underwent transapical mitral valve-in-valve implantation. Median age was 79 years. Preoperatively, all patients presented in New York Heart Association functional class III. For risk estimation, The Society of Thoracic Surgeons and European System for Cardiac Operative Risk scores were used and predicted high mortality (mean ± standard error of mean: Society of Thoracic Surgeons mortality, 12.3% ± 2.1%; European System for Cardiac Operative Risk mortality, 58.0% ± 7.0%). Mean follow-up time was 93 ± 29 days, with a total of 21.6 patient-months. RESULTS Preoperatively, all patients who had deteriorated bioprostheses presented with severe regurgitation and increased transvalvular pressure gradients (maximal pressure gradient, 23.9 ± 0.9 mm Hg; mean pressure gradient, 11.3 ± 1.0 mm Hg). One patient was identified with mitral valve stenosis (effective orifice area, 0.25 cm(2)). All patients underwent successful transapical mitral valve-in-valve implantation. Sizes of previously implanted bioprostheses were 27, 29, and 31 mm; Edwards SAPIEN valves at sizes 26 and 29 mm were implanted. Postoperatively, echocardiography revealed excellent hemodynamics with no remaining mitral regurgitation in 5 patients and minimal regurgitation in 2 patients. Transvalvular pressure gradients decreased significantly (maximal pressure gradient, 13.8 ± 2.1 mm Hg; mean pressure gradient 5.7 ± 0.8 mm Hg, p < 0.05). One patient had fatal pneumonia on postoperative day 34. No patient died during further follow-up, and all patients remained in New York Heart Association class I or II. CONCLUSIONS Our results demonstrate the feasibility of transapical mitral valve-in-valve implantation for treatment of a degenerated bioprosthesis (size range, 27 to 31 mm) using the Edwards SAPIEN valve in sizes 26 and 29 mm.

New telemetric system for daily pulmonary function surveillance of lung transplant recipients

BACKGROUND Following lung transplantation, prompt diagnosis and therapy of acute pulmonary rejection and infection episodes relies primarily upon changes in pulmonary function and determines long-term outcome. We tested a new system that allows daily monitoring of the patients pulmonary status even after discharge from the hospital. METHODS Seven lung transplant recipients from our center were equipped with a telemetric monitoring device consisting of a portable flowmeter and a special modem unit. The flowmeter measures forced vital capacity (FVC), forced expiratory volume per second (FEV1), and mid expiratory flows (MEFs), encodes information like fever, cough, and dyspnea in a binary code form, and stores all values in a 32 kB memory unit. After its use, the patient positions the flowmeter onto the modem unit which automatically connects to a central computer at our center to transfer all saved data. The whole set can be used via any regular phone jack. The patients file in the computer can be checked every day. RESULTS All patients learned to use the unit during their postoperative stay or during later follow-up, and were able to apply the system at home. In a mean follow-up period of 10.3+/-2.2 months, 15 episodes of significant deterioration in home pulmonary function tests (PFTs) (>10%) were registered in 6 patients, which were all confirmed by in-hospital body plethysmography. They resulted in diagnoses of 4 episodes of acute rejection, 6 cases of beginning bacterial pneumonia, and 5 cases of, most likely, viral tracheobronchitis. Only 1 patient had to be admitted to the hospital. All patients PFTs returned to previous values after treatment. CONCLUSIONS Telemetric monitoring of graft function in lung transplant recipients allows reliable early diagnosis and treatment of infection or rejection, which might help to prevent exacerbation of the pathology and reduce quantity of amounting graft dysfunction.

Even short-time storage in physiological saline solution impairs endothelial vascular function of saphenous vein grafts

OBJECTIVES A faultless endothelial layer is decisive for vascular function and therewith grafts patency. Functional impairment of the endothelium increases risk of graft thrombosis, intimal hyperplasia, and consecutive accelerated graft atherosclerosis. Storage solutions for intra-operatively harvested saphenous vein segments (SVS) might have significant impact on endothelial function. We investigated the impact of short-time storage in physiological saline solution (PSS) and a potassium-chloride- and N-acetylhistidine-enriched storage solution on venous endothelial function. METHODS Intra-operatively isolated SVSs (n=19) were stored in different storage solutions for 90 min. They were then immediately studied in tissue bath at 36°C with continuous oxygen insufflation. Following preconstriction with norepinephrine, dose-response relaxation curves of bradykinine (Brad) and sodium nitroprusside (SNP) were determined. We compared developed maximum wall tension, vessel constriction kinetics, endothelial cell- and smooth muscle cell (SMC)-dependent vasodilatory function. RESULTS Maximum vessel wall tension was reduced significantly in PSS-stored vessels (10.1 ± 9.8 mN mm(-1) vs 3.5 ± 3.4 mN mm(-1); p=0.0372). Endothelium-derived vasodilatory function was likewise significantly reduced after short-time storage (20.6 ± 34.4% vs 35.0 ± 27.0%; p=0.0437). SNP-mediated SMC-vasodilatory function was maintained equally well in both groups (88.2 ± 21.8% vs 83.0 ± 30.6% in PSS; p=n.s.). CONCLUSION Even short-time storage in PSS significantly impairs endothelial vascular function. Concerning the essential role of a faultless endothelial layer, the quite common use of PSS as a storage solution for SVSs in CABG surgery has to be discussed critically.

Minimally invasive mitral valve surgery – clinical experiences with a PortAccess system

OBJECTIVE This is the initial experience with a new minimally invasive surgical technique for the treatment of mitral valve disease using a PortAccess system. METHODS Between May 1996 and May 1997, 21 patients (nine male, 12 female, aged 30-75 years, median 64 years) underwent minimally invasive mitral valve surgery. The underlying diseases were: mitral valve insufficiency (n = 11), mitral valve stenosis (n = 5) and combined mitral valve disease (n = 5). Through a small right thoracotomy (6-8 cm) access to the pericardium and the heart was gained. Cardiopulmonary bypass was instituted through femoral cannulation and an intraaortic balloon-catheter (Heartport Inc., Redwood City, CA) was introduced for aortic occlusion, aortic root venting and delivery of cold crystalloid cardioplegia. Mitral valve repair (four patients) or replacement (15 patients) was performed. RESULTS There was no death during the whole follow-up period. There was no perivalvular leak and only minor residual mitral valve regurgitation was observed on intraoperative or postoperative (3 months) transesophageal echocardiography. There was no postoperative study-related complication. Time of ventilation, intensive care unit and hospital-stay were comparable with the data of patients undergoing conventional mitral valve surgery. CONCLUSIONS This technique of PortAccess mitral valve surgery combines the advantage of less invasive operative trauma with the safety of conventional mitral valve surgery.

Preservation of endothelial vascular function of saphenous vein grafts after long-time storage with a recently developed potassium-chloride and N-acetylhistidine enriched storage solution.

OBJECTIVES Saphenous vein grafts are still commonly used in cardiac, vessel and also in transplant surgery. In cardiac surgery, a desperate graft situation could force to keep nonutilized explanted vein segments after CABG in reserve for case of early graft failure. Historically there were no options for adequate long-time graft storage protecting the endothelial layer with its important antithrombotic and immunosuppressive functional aspects. Commonly isotonic saline solution (sodium chloride [NaCl]) has been used as a storing solution in this case. We investigated the impact of long-time storage in NaCl and a recently developed potassium-chloride and N-acetylhistidine enriched storage solution (TiProtec, Dr. Köhler Chemie, Germany) on endothelial function of saphenous veins. METHODS Saphenous vein segments (n = 19) were intraoperatively isolated and stored for 24 and 96 hours. The segments were examined in a Mulvany-myograph to assess vessel function. Following preconstriction with norepinephrine, dose-response curves were assessed for relaxation with bradykinin and sodium-nitroprusside. We compared developed maximum wall tension and endothelial cell and smooth muscle cell (SMC) dependent vasodilatory function. RESULTS Maximum vessel wall tension was significantly better preserved in TiProtec-stored vessels after 24 h in comparison to segments stored in NaCl (5.11 ± 4.79 mN/mm vs. 2.48 ± 2.43 mN/mm; p = 0.033) and 96 h (4.94 ± 2.82 mN/mm vs. 2.80 ± 1.76 mN/mm; p = 0.042). Likewise endothelium-derived vasodilatory function was maintained significantly after 24 hours in TiProtec-stored vessels (36.9 ± 2.6% vs. 11.8 ± 30.9%; p = 0.005). After 96 hours, endothelium-dependent vascular function was nearly abolished in NaCl-stored vessels, but largely preserved in TiProtec-stored segments (20.6 ± 2.9% vs. 1.9 ± 4.3% in NaCl; p = 0.015). Sodium nitroprusside-mediated SMC-vasodilatory function was better maintained after 24 hours of storage in TiProtec group (88.8 ± 6.4% vs. 61.3 ± 8.2%; p = 0.009). After 96 hours of storage, SMC relaxation did not significantly differ between both storage groups which might be due to a distinct reduction of contractile function in NaCl-stored vessels (98.6 ± 5.0% and 77.9 ± 10.5% for Tiprotec and NaCl, respectively). CONCLUSION Vessel functions comprising contraction, endothelium-dependent and -independent vasodilatation are significantly reduced following 24 hours of cold storage in NaCl. After 96 hours of storage in NaCl these functions are nearly totally abolished. TiProtec is able to largely reduce this loss of function during cold storage. Therefore, TiProtec is a feasible option for longer term storage of saphenous vein grafts in CABG vessel and transplant surgery.

[Do drug-eluting stents influence the spectrum of coronary artery bypass surgery?].

Hintergrund:Die Anzahl der chirurgischen koronaren Revaskularisationsoperationen stagniert und ist in den letzten Jahren sogar leicht rückläufig. Die Frage ist, ob die Einführung von Drug-eluting Stents das Operationsspektrum der Koronarchirurgie beeinflusst.Koronarchirurgie:Die Koronarchirurgie ist ein etabliertes Verfahren zur Behandlung der koronaren Herzerkrankung mit guten Ergebnissen. Studien belegen auch einen Vorteil zugunsten der Chirurgie im Verhältnis zur interventionellen kardiologischen Therapie.Drug-eluting Stents:Die jetzt zur Verfügung stehenden Stents neuester Generation, Drug-eluting Stents, zeigen in ersten Studien eine signifikant günstigere Offenheitsrate als herkömmliche Stents. Zurzeit gibt es aber keine Studien, die auch einen Vorteil gegenüber der chirurgischen Therapie bei gleicher Indikation erbringen.Schlussfolgerung:Es ist daher zum jetzigen Zeitpunkt nicht eindeutig zu beantworten, inwieweit das Spektrum der Koronarchirurgie durch Drug-eluting Stents beeinflusst wird.Background:The number of surgical coronary revascularization procedures is static and even declining. Since the introduction of drug eluting stents the question arose whether this will have an impact on the spectrum of surgical coronary revascularization procedures.Bypass Surgery:Bypass surgery is a routine procedure for the treatment of coronary artery disease with good results. Studies have shown that there is a benefit in favor of surgery compared to interventional cardiologic procedures.Drug-Eluting Stents:In recent studies a new generation of stents, drug-eluting stents, have proven to have a significant better patency rate than common stents. However, to date there are no studies which show a benefit compared to surgery given the same indication for treatment.Conclusion:Therefore, the question whether drug-eluting stents have an impact on the spectrum of bypass surgery cannot be fully answered at present.

Prolonged intensive care unit stay of patients after cardiac surgery: initial clinical results and follow-up.

BACKGROUND Prolonged intensive care unit (ICU) stay in cardiac surgery patients often results in a poorer clinical course and decreased survival postdischarge. Data on clinical outcomes and prognosis are limited. We aimed to identify perioperative factors that would predict prolonged ICU stay and to evaluate their impact on clinical outcomes. PATIENTS AND METHODS Demographic and clinical data on the perioperative course and outcome of 7,646 consecutive patients who underwent cardiac surgery at our institution were retrospectively analyzed over a 4-year period. Duration of ICU stay was defined as: less than 3 days (Group 1, n = 6,574), greater than 3 days (Group 2, n = 466), and more than 7 days (Group 3, n = 606). RESULTS The in-hospital mortality rate was significantly elevated in patients with a prolonged ICU stay (Group III, 16.1%; Group II, 8.4%; and Group I, 2.5%; p < 0.05). Prolonged ICU stay was associated with a complicated clinical course and a significantly higher incidence of respiratory and renal insufficiency. Multivariate analysis confirmed neurological, renal, and respiratory complications to be the predictive of prolonged ICU stay. Two-year survival also correlated with duration of ICU stay (Group I, 85.9%; Group II, 64.2%; and Group III, 57.4%; p < 0.0001). CONCLUSION Prolonged ICU stay is associated with a complicated clinical course and decreased overall survival. Treatment for patients with respiratory impairment should be aggressively optimized.

Isolated aortic valve replacement in patients with small aortic annulus-a high-risk group on long-term follow-up.

BACKGROUND Patients with small aortic annulus undergoing isolated aortic valve replacement face an often underestimated surgical risk. We describe initial clinical results and long-term follow-up of this particular high-risk group. METHODS Between January 1998 and December 2004, 148 consecutive patients with small aortic annulus underwent isolated aortic valve replacement by implantation of a Mitroflow Aortic Pericardial Heart Valve (Sorin S.p.A., Milano, Italy) 19 or 21 mm bioprostheses. Mean age was 75.4 ± 6.2 years. Female gender, obesity, and multiple comorbidities were predominant. Mean logistic euroSCORE for mortality was 18.5 ± 2.3%. Follow-up time was 7.2 ± 2.0 years, with a total of 1,066 patient years. RESULTS Postoperative course and outcome during follow-up were strongly influenced by extracardiac morbidities. Hospital mortality was 6.1%, 5-year survival 71.9%, and 10-year survival 40.9%. Most patients (70.0%) died because of extracardiac reasons. Significant reasons for death were age, pre-existing atrial fibrillation, diabetes mellitus type 2, chronic renal failure, extracardiac vascular disease, history of stroke, and preoperative presentation at Canadian Cardiovascular Society class III and IV (p < 0.05). Freedom from valve-related reoperation was 99.1% at 5 years and 93.4% at 10 years. Prosthesis-patient mismatch occurred in 12.2% and was not affected with any adverse outcome (p = nonsignificant). Echocardiographic data demonstrated a significant reduction of mean transvalvular gradients in all patients (61.2 ± 19.7 mm Hg preoperatively; 18.0 ± 8.0 mm Hg during follow-up; p < 0.05). All patients reported a significant improvement in New York Heart Association functional class (p < 0.05). CONCLUSION Patients with small aortic annulus are predominantly small, obese, and old-aged females with multiple comorbidities. Mitroflow valve avoids prosthesis-patient mismatch and provides excellent hemodynamics. Observed long-term results were disappointing, but they were mainly limited by extracardiac comorbidities and advanced age.