[Surgery of the ascending aorta and aortic arch]. / Chirurgie der Aorta ascendens und des Aortenbogens.

The surgical therapy of the ascending aorta and the aortic arch with its supraarotic branches has been, and still is, one of the major challenges in the therapy of the aorta. There have been major developments in the endovascular therapy field, which can be used as a complementary or even sometimes as an alternative to the standard surgery. Therefore, an interdisciplinary approach is a prerequisite for optimal therapy planning for such patients. The risk of operating under circulatory arrest has been markedly reduced due to the continued development of cardiosurgical techniques, especially selective cerebral perfusion and mild hypothermia. Further developments of the therapy of aortic diseases via alternative approaches are expected in the near future. However, the conventional surgical therapy for pathologies in the ascending aorta (with/out the aortic valve) and the aortic arch is still the gold standard.

Combined immunosuppressive therapy including a TNF-alpha blocker induces remission in a difficult to treat patient with Takayasu arteriitis and coronary involvement.

A 40 year old woman presented with symptoms of a systemic inflammatory disease and obstruction of the left subclavian artery. Takayasu arteriitis (TA) was clinically diagnosed and confirmed by MR angiography and FDG-PET scan showing inflammation of the aortic arch and the left subclavian artery. Immunosuppression with glucocorticoids and methotrexate resulted in immediate clinical improvement and normalization of systemic markers of inflammation. Despite that the patient developed chest pain on exertion suggesting coronary involvement, which was confirmed by dobutamine stress echocardiography. After adding the TNF-alpha blocker infliximab coronary symptoms gradually improved and a clinically stable situation could be achieved for more than 6 months. Coronary angiography and aortography showed an occluded main stem of the left coronary artery, an occluded left subclavian artery, and stenoses of the brachiocephalic trunk and the left common carotid artery. Revascularization of the coronary artery and the aortic arch and its branches was performed. The patient returned to work two months after the operation. Immunosuppressive therapy with infliximab and methotrexate is continued, glucocorticoids were stopped after one year of treatment. This case shows that vascular progress in TA patients may occur even when systemic inflammation is controlled, therefore patients have to be carefully observed for new vascular manifestations. TNF-alpha blockers may be an additional treatment option in otherwise difficult to treat TA patients allowing to perform revascularization after a stable disease state has been achieved.

Intra-aortic balloon pump implantation does not affect long-term survival after isolated CABG in patients with acute myocardial infarction.

BACKGROUND: Intra-aortic balloon pump (IABP) is an established therapy to support patients with heart failure during coronary artery bypass grafting (CABG). The impact of the timing of IABP on the hospital course and on follow-up is of particular clinical interest. The purpose of this study was to analyze the relationship between the time of IABP implantation and its impact on early, mid- and long-term survival in patients with acute myocardial infarction (AMI) who underwent emergent CABG for NSTEMI and STEMI. METHODS: A total of 472 patients with AMI (NSTEMI and STEMI) underwent emergency CABG at our institution; 158 of them additionally received IABP support. Fifty-seven (36 %) patients received preoperative and 101 (64 %) patients underwent intraoperative IABP implantation. Endpoints were in-hospital und follow-up (mean duration 37 ± 28 months) survival. RESULTS: Overall in-hospital mortality was 17.1 % (n = 27): 17.6 % (n = 10) in the preoperative group and 16.8 % (n = 17) in the intraoperative group ( P = ns). Mid- and long-term survival rates were comparable for both groups 78.6 % vs. 73.7 %, 71.4 % vs. 68.7 % and 64.3 % vs. 54.6 % at 1, 3 and 5 years, respectively ( P = ns). CONCLUSION: This study demonstrates that CABG with IABP support in high-risk patients with AMI can be performed with acceptable in-hospital and long-term survival rates. The decision for IABP placement should consider the preoperative clinical condition and the intraoperative course of each patient. IABP placement does not appear to affect the long-term outcome after isolated CABG in patients with AMI.

The C-Port xV® vascular anastomosis system: results from an animal trial.

BACKGROUND: In this study, facilitated anastomosis using an anastomotic device was compared to conventional hand-sewn (HS) vascular anastomosis in an animal model. METHODS: A pig carotid bypass model was employed. C-Port xV® (xV) and HS anastomoses were compared by evaluating intraoperative performance, midterm graft patency, and histology. RESULTS: All animals survived; none developed early/late neurological deficits. Mean graft blood flow was comparable between groups (HS group: 161 ± 61 ml/min; xV group: 143 ± 44 ml/min). All anastomoses were patent at necropsy (at 111 ± 6 postoperative days). Histologically, no significant inflammation was found around the fasteners or in the vessel wall. Neointimal overgrowth on the lumen surface appeared organized and covered with endothelium. There was no adherence of fibrin, platelets, or inflammatory cells to the surface. The neointimal tissue appeared normal without any inflammation, hemorrhage, calcification, or necrosis. CONCLUSION: Facilitated vascular anastomosis using the xV anastomotic device is safe and effective in the pig carotid bypass model. Further studies should evaluate the efficacy of this device when used in confined spaces to define its potential role in minimally invasive procedures.

Development of robotic enhanced endoscopic surgery for the treatment of coronary artery disease.

BACKGROUND: The introduction of robotic enhanced surgery demanded stepwise development of performed procedures on the basis of growing experience of the operating team. METHODS AND RESULTS: Between May 1999 and January 2001, this new wrist-enhanced instrumentation was used in 201 patients (156 men and 45 women, median age 64+/-10.5 years, left ventricular ejection fraction 68+/-12.4%). During the development of robotic enhanced CABG, the patients were divided into 3 groups. Group A (n=156) consisted of patients in whom the robotic system was used to harvesting the left or right internal mammary artery, or both, whereas the anastomoses were performed directly through a small chest incision. In group B (n=37), the harvest of the internal mammary arteries and the coronary anastomoses were performed totally endoscopically. In a third early group C, patient (n=8) were treated with robotic enhanced CABG via a median sternotomy already preoperatively planned, whereas gradual step-by-step application of robotic instrumentation and its feasibility were assessed. The survival rate was 99.4%. One patient (0.6%) died due to pneumonia on postoperative day 16. Conversion rate to median sternotomy was 5%. The left and right internal mammary artery conduits could be successfully harvested in 98% and 100%, respectively. The time of dissection of the left internal mammary artery could be significantly reduced alone by increasing experience. All patients were discharged from the hospital after a mean of 7 days. In 9 patients (4.5%), bleeding required reexploration. CONCLUSIONS: The introduction of this new surgical tool enables the development of new endoscopic procedures. Our results gained during the development of robotic enhanced CABG motivate us to establish a set standard for the totally endoscopic treatment of patients with 1-vessel coronary artery disease.

Lactatdehydrogenase (LDH) prior and post implantation of ATS heart valves.

Establishing guidelines towards an assessment of prostheses dysfunction using LDH as a marker is difficult as shown by [M. Suedkamp, A.J. Lercher, F. Mueller-Riemenschneider, K. LaRosee, P. Tossios, U. Mehlhorn, Hemolysis parameters of St Jude Medical hemodynamic valves in aortic position, Int. J. Cardiol (95) (2004) 89-93]. In response to their work we would like to add our data concerning ATS valves (AP) and say a word of caution in interpreting an increase of LDH values.

Closed chest bilateral mammary artery grafting in double-vessel coronary artery disease.

A clinical case of a closed chest double-vessel total endoscopic coronary artery bypass procedure was performed using a wrist-enhanced, three-dimensional-based robotic system. A patient suffering from lesions of the left coronary artery system was effectively treated surgically without median sternotomy or minithoracotomy. This encourages optimism for introducing closed chest endoscopic bypass operations into the surgical routine for patients suffering from double-vessel coronary artery disease.

Early experience with a quadrileaflet stentless mitral valve.

BACKGROUND: Presently no ideal prosthesis for mitral valve replacement exists. The quadrileaflet mitral valve (SJM-Quattro-MV; St. Jude Medical, Inc, St. Paul, MN) is a chordally supported stentless bioprosthesis. Due to its specific geometry it seems to be particularly suited for mitral valve replacement. METHODS: From March 1999 to October 2000, 12 patients (ages 71+/-2 years) received the SJM-Quattro-MV. Six patients suffered from valvular stenosis and 6 patients from incompetence. Preoperatively, all patients were in New York Heart Association functional class III, with left ventricular ejection fraction amounts of 54%+/-17%. RESULTS: Eleven patients received a medium size SJM-Quattro-MV and one patient received a large size SJM-Quattro-MV. Cross-clamp time was 99.8+/-4.9 minutes. Additional procedures were coronary artery bypass grafting (n = 3) and left atrial microwave ablation (n = 2). Postoperative mortality (n = 1) was procedure related. At follow-up of 11.6+/-5.4 months, all patients were well, the transvalvular pressure gradient was 5.0+/-1.4 mm Hg, and the effective orifice area 2.7+/-0.2 cm2. CONCLUSIONS: Our preliminary experiences with the SJM-Quattro-MV presented good clinical results and promoted an optimistic way of thinking about the further development of these valve prostheses.

The Dresden approach for complete multivessel revascularization.

BACKGROUND: In a prospective clinical trial, a group of patients receiving less invasive surgical procedure, including minithoracotomy in combination with cardiopulmonary bypass (group 1), was compared to a group of patients receiving conventional bypass surgery (group 2) for the treatment of coronary artery disease. METHODS: Group 1 included 85 patients (71 men, 14 women, aged 39 to 82 years, median 61.1 +/- 9.0 years); group 2 included 53 patients (38 men, 15 women, aged 51 to 79 years, median 62.0 +/- 6.1 years). RESULTS: There were no perioperative deaths in the whole series of patients. Time of operation was 256 +/- 43 minutes in group 1 and 150.0 +/- 53.6 minutes in group 2. Hospitalization was 6.0 +/- 1.4 days and intensive care unit stay 1 day for both groups. Back pain assessment on postoperative day 3 showed less pain in group 1. Three-month follow-up revealed ischemia in stress electrocardiogram in 2 patients (2.5%) in group 1 and in 2 patients (4.1%) in group 2. Coronary angiograms confirmed the stress-electrocardiogram findings. CONCLUSIONS: Surgical results are equal for both techniques. Even though time of operation is longer in patients receiving less invasive procedures, intensive care unit stay and hospital stays are the same length. Early postoperative back pain is less in group 1 and combined with faster convalescence.

Robotic-enhanced arterial revascularization for multivessel coronary artery disease.

BACKGROUND: A tendency to reduce operative trauma is determining the evolution of cardiac surgical techniques lately. The introduction of robotic-enhanced endoscopic systems enables surgeons to perform arterial revascularization for multivessel disease without sternotomy. METHODS: From May 1999,17 (4 women, 13 men; median age 63+/-7.4 years) patients with multivessel coronary artery disease were treated surgically using arterial revascularization by means of bilateral internal mammary arteries. Both arteries were harvested endoscopically using the da Vinci system (Intuitive Surgical, Mountain View, CA). These vessels were anastomosed using the "Dresden technique." RESULTS: Survival was 100%. Mean duration of the operation was 255+/-40.4 minutes. Bilateral internal mammary artery harvesting took 88.5+/-15.9 minutes; cross-clamp time was 36+/-8.7 minutes. An average of 2.06 anastomoses were performed per operation. Postoperatively, patients remained in the intensive care unit for 21+/-13 hours. One patient (5.8%) needed reexploration due to bleeding. CONCLUSIONS: The robotic surgical system introduces a new treatment of coronary artery disease to surgical practice, and enables arterial revascularization with distinctly reduced surgical trauma.

Wrist-enhanced instrumentation: moving toward totally endoscopic coronary artery bypass grafting.

BACKGROUND: With the introduction of the da Vinci robotic surgical system (Intuitive Surgical, Mountain View, CA) into minimally invasive cardiac operations the outlook for performing coronary artery bypass operations "closed chest" became a reality. METHODS: Between May 1999 and December 1999 this new wrist-enhanced instrumentation was used in 61 patients. Six patients suffering from single-vessel coronary artery disease and one female patient with double-vessel disease underwent totally endoscopic coronary artery bypass. Thirty-seven patients with single-vessel disease underwent a minimally invasive direct coronary artery bypass procedure. Seventeen patients with double-vessel disease were treated using the robotic-enhanced Dresden technique. RESULTS: Perioperative survival was 100%. In all patients the internal mammary arteries were safely harvested endoscopically and had excellent quality. In both totally endoscopic coronary artery bypass groups all patients were operated on through three stab incisions. CONCLUSIONS: Our preliminary experience with this new surgical technique using robotic-enhanced minimally invasive methods for coronary artery disease promotes optimism regarding further development of these procedures and application in patients with coronary artery disease.

The application of the Octopus stabilizing system for the treatment of high risk patients with coronary artery disease.

OBJECTIVES: If coronary disease is the target of a minimally invasive procedure, median sternotomy or cardiopulmonary bypass or both can be avoided. Similar to the development in other fields of surgery, minimally invasive surgical techniques are gaining increased acceptance in the field of cardiothoracic surgery. Our experience with an off pump coronary artery bypass (OPCAB) technique in a special patients group with serious risk factors for the application of cardiopulmonary bypass has been analyzed. METHODS: Between March 1996 and January 1999, 88 patients (64 male, 24 female) with impaired left ventricular function, or other high risk factors jeopardizing the use of cardiopulmonary bypass, such as impaired renal or lung function or heavily calcified aorta, received a beating heart procedure using the Medtronic Octopus stabilizing system. RESULTS: All patients survived the actual operation, however, two multimorbide patients died of pneumonia on postoperative day 31 and postoperative day 35. CONCLUSIONS: Patients with single-vessel to multivessel disease and serious risk factors for cardiopulmonary bypass can be safely treated by OPCAB surgery. At our institution this technique presents the procedure of choice in this particular patients group.

Port Access surgery for congenital heart disease.

OBJECTIVES: Minimally invasive surgical techniques have been introduced into cardiac surgery in order to avoid median sternotomy related complications. Surgical trauma to the patient can be significantly reduced without compromising the safety. In addition, a small lateral chest incision results in improved cosmesis, especially in female patients. METHODS: Thirteen patients (median age 39 +/- 14 years, ranged from 17-61 years) with atrial septal defect were treated with a minimally invasive surgical method using a modified Port Access technique. In all patients access to the heart was achieved via a small (4-8 cm) right lateral chest incision in the 4th intercostal space. In these patients the selection of the Port Access system was used for cardiopulmonary bypass via the femoral vessel and for the application of cardioplegic solution. RESULTS: No deaths or intraoperative complications were observed in any of the patients. The postoperative course was uneventful and only minor complications were observed postoperatively. The median hospital stay was 8.0 +/- 1 days (median +/- SEM). CONCLUSION: This minimally invasive surgical technique for the treatment of atrial septal defects represent a safe alternative to conventional treatment of ASD using median sternotomy and standard cardiopulmonary bypass. The exposure of the right atrium via the 4th intercostal space is ideal and can be performed with excellent cosmetic results.

Experiences with a minimally invasive surgical technique for the treatment of coronary artery multivessel disease in 100 patients.

OBJECTIVE: The treatment of coronary single vessel disease under minimally invasive surgical conditions was followed by the treatment of coronary multivessel disease using a new technique. METHODS: Using this technique 100 patients (80 male, 20 female, median age 61.0+/-8.9 years, ranged from 39 to 82 years) with coronary single vessel disease, double vessel disease or multivessel disease were treated between November 1996 and December 1997. Via a small (6-9 cm) left lateral chest incision in the second or third intercostal space, the left internal thoracic mammary artery (LIMA) was harvested and access to the central portion of the heart including the ascending aorta was obtained. In parallel, saphenous vein segments were harvested. Arterial cannulation was instituted via the ascending aorta, thus avoiding retrograde flow. In all patients except three the LIMA was used for the left anterior descending artery (LAD). In addition vein grafts were used for revascularization of the other coronary arteries. All cardiac anastomoses were performed during cardioplegic arrest after external aortic cross clamping and antegrade application of cardioplegia. RESULTS: No death or intraoperative complications were observed in this series. The median hospital stay was 6.0+/-1.4 days (median+/-SEM). Postoperative complications were reexplored for bleeding (n = 1), delayed wound healing (n = 2), wound infections (n = 4), lymphatic fistulas (n = 4), and a chest wall hernia (n = 1). CONCLUSIONS: This minimally invasive surgical technique presents a safe alternative to conventional coronary artery surgery avoiding sternotomy related complications and decreasing hospital stay and morbidity.

Technique of closed chest coronary artery surgery on the beating heart.

OBJECTIVE: The application of an endoscopic stabilizer (Intuitive Surgical, Mountain View, CA, USA) enables closed chest off-pump coronary artery bypass via a four-point stab incision avoiding sternotomy and minithoracotomy. METHODS: Between May 1999 and January 2001 we operated upon a total of 37 patients (five female, 32 male, median age 62+/-9 years) suffering from coronary artery disease using totally endoscopic coronary artery bypass (TECAB), whereas an initial series of eight TECAB patients was operated upon using an endovascular bypass system (Heartport). The da Vinci surgical system was used in order to perform left internal mammary artery (LIMA) or right internal mammary artery (RIMA) harvesting and anastomoses on a beating heart in 29 patients (four female, 25 male, median age 64+/-9.8 years). Altogether 26 patients suffering from single-vessel coronary artery disease (SVCAD) were revascularized applying LIMA to the left anterior descending artery (LAD) and three patients with two diseased coronary vessels received bilateral internal mammary artery grafting (BIMA), respectively. RESULTS: In this series we had a 100% survival rate. Conversion rate to a median sternotomy was 3.4%. Patients were operated upon via four 1-cm chest incisions using the da Vinci robot for LIMA or BIMA harvesting and for performance of anastomoses on the beating heart. In the overall series of 56 patients intended to be treated by TECAB, 19 (33.9%) were converted to a minimally invasive direct coronary artery bypass procedure. CONCLUSION: This new robotic-enhanced surgical technique promotes an optimistic way of thinking about the further development of this procedure and its application in patients suffering from single-vessel CAD.

The medical engineering program of Forschungszentrum Karlsruhe.

The research activities of the Forschungszentrum Karlsruhe on minimally-invasive surgery (MIS) have for several years improved techniques and instrumentation for different types of MIS. Many types of instruments and robotic devices have been developed and new techniques implemented. In this paper we present the most recent results from our different projects, such as endoscopic heart surgery, tracking systems, a camera guidance device, telemanipulator systems, minimally-invasive breast biopsy in closed-bore MRI, endoscopic training simulators and developments using smart materials (e.g. Nitinol).

Clinical course after surgical treatment of active isolated native mitral valve endocarditis.

AIM: Isolated mitral valve endocarditis (MVE) forms a particular subgroup within native infective valve endocarditis (NVE). We characterized this particular subgroup and analyzed the course of patients undergoing cardiac surgery. METHODS: Between 1997 and 2011, 474 patients underwent cardiac surgery at our institution for NVE treatment. Of these, 89 patients (18.8%) suffered from MVE. Valve replacement was undertaken in 84.2% and valve repair in 15.8%. Follow-up was completed with 267 patient years. RESULTS: A delay between the onset of first symptoms and surgery of 4.7±1.2 weeks was observed. Hence, most patients were in a critical preoperative state characterized by severe sepsis and destruction of the mitral valve. About 19.4% were emergency procedures. The MVE group presented with a higher prevalence of preoperative stroke, atrial fibrillation, coronary artery disease and chronic obstructive pulmonary disease in comparison with remaining NVE cases. MVE was more likely caused by Staphylococcus aureus; Staphylococcus epidermidis and Staphylococcus viridans were less frequent (P<0.01 each). Early mortality (6.7%) was caused by persistent sepsis. ICU stay >7 days and time on artificial ventilation >40 h led to a higher risk of in-hospital death. Five-year survival was 59.6% and affected by extracardiac comorbidities. CONCLUSION: Isolated MVE was characterized by a long delay before surgery, differences in microbiological findings and a higher prevalence of preoperative strokes in comparison to NVE. Surgery for MVE can be conducted with good clinical results, but mid-term outcome is limited by extracardiac comorbidities.

Readmission to the intensive care unit after cardiac surgery: a single-center experience with 7105 patients.

AIM: Identification of patients at high risk for readmission to the Intensive Care Unit (ICU) after cardiac surgery is paramount. We evaluated the clinical characteristics of readmitted patients and identified perioperative prognostic variables for ICU readmission. METHODS: A total of 7105 patients who underwent cardiac surgery between 2007 and 2010 and discharged after a primary stay in the ICU were reviewed retrospectively. Of these, 7.8% (554) patients were readmitted. The reasons for readmission and postoperative course were analyzed. Perioperative risk factors for readmission were determined by multivariate regression analysis. RESULTS: Mortality of patients after readmission was 13.6% compared with 0.2% without recidivism (P<0.0001). Mean length of stay in hospital of patients requiring readmission was 24.9 ± 19.1 days and significantly longer compared to all other patients 12.3±8.4 days (P<0.0001). The main reasons for readmission were respiratory failure (39.0%) and cardiovascular instability (26.2%). Complex cardiac surgery, aortic surgery and extended stay in the ICU were the most powerful variables to predict ICU readmission. CONCLUSION: ICU readmission was related to complex surgery and associated with impaired outcome. Respiratory complications were the most common reasons for readmission. Predictive renal and pulmonary risk factors indicate the need of preoperative preconditioning and patient selection.

[Transapical aortic valve implantation--indications, risks and limitations]. / Transapikaler Aortenklappenersatz--Indikationen, Risiken und Grenzen.

Calcified aortic stenosis is the predominant valve disease in the western world. Currently, surgical aortic valve replacement is the gold standard procedure for symptomatic severe aortic stenosis that can be performed with low morbidity and mortality. The prevalence of aortic stenosis increases with age, and the incidence of several comorbidities also unavoidably elevates the risk of surgical treatment. Therefore, the most adequate and gentle treatment is needed especially for this population. Since the first transcatheter aortic valve implantation (TAVI) was performed in 2002, the main implanting routes are the transfemoral, retrograde access through the common femoral artery, and the antegrade, transapical approach via anterolateral minithoracotomy. Meanwhile, TAVI has become an alternative treatment for patients who are not suitable candidates for surgical therapy in some centers.The initial clinical results are promising and have confirmed the feasibility of this technique. Due to the restricted long-term data, conventional aortic valve replacement still remains the standard for the treatment of aortic stenosis. Selection of the suitable therapy approach (surgical replacement, transfemoral or transapical aortic valve implantation) must consider each patient's specific risk profile and individual indication. Prospective, randomized trials will be necessary to assess the individual survival benefit of TAVI for various risk populations and to extend the indication.