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S Schueler

Publications and source records attributed to S Schueler.

At least 19 recordsLinked to original sources
PubMed2001

STR primer concordance study.

Over 1500 population database samples comprising African Americans, Caucasians, Hispanics, Native Americans, Chamorros and Filipinos were typed using the PowerPlex 16 and the Profiler Plus/COfiler kits. Except for the D8S1179 locus in Chamorros and Filipinos from Guam, there were eight examples in which a typing difference due to allele dropout was observed. At the D8S1179 locus in the population samples from Guam, there were 13 examples of allele dropout observed when using the Profiler Plus kit. The data support that the primers used in the PowerPlex 16, Profiler Plus, and COfiler kits are reliable for typing reference samples that are for use in CODIS. In addition, allele frequency databases have been established for the STR loci Penta D and Penta E. Both loci are highly polymorphic.

Alleles↗
PubMed2001

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.

Anesthesia↗
PubMed2001

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.

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PubMed2001

Anti-proliferative properties of the phosphodiesterase-4 inhibitor rolipram can supplement immunosuppressive effects of cyclosporine for treatment of obliterative bronchiolitis in heterotopic rat allografts.

BACKGROUND: Potent prevention and therapy of obliterative bronchiolitis may enhance long-term survival after lung transplantation. Phosphodiesterase-4 inhibitors have been established for anti-inflammatory treatment, particularly of pulmonary diseases. Using a heterotopic rat model, the effect of rolipram was investigated and compared with cyclosporine for epithelium disturbance and leukocyte infiltration and proliferation, which are key events in the development of obliterative bronchiolitis. METHODS: Tracheae were transplanted into the omentum of allo- and syngeneic animals. Four allogeneic groups were investigated: treatment with rolipram; treatment with cyclosporine; treatment with a combination of rolipram and cyclosporine; and untreated (60-day time course). Using histo- and immunohistochemical stainings, epithelium disturbance, leukocyte subsets, proliferating cells and luminal occlusion were quantified by digital morphometry. RESULTS: In rolipram-treated animals, the epithelium was completely disturbed until Day 14. It was temporarily preserved in rats that received cyclosporine until Day 60. In the acute phase (Day 5), infiltration of monocytes/macrophages was significantly inhibited by rolipram, but less effective than in cyclosporine-treated rats. At later timepoints (Days 28 and 60), rolipram significantly inhibited proliferation, in contrast to enhanced proliferation of fibroblast-like cells after cyclosporine treatment. The combination of rolipram and cyclosporine led to temporary epithelial preservation and effective inhibition of leukocyte infiltration (Day 5) and proliferation (Days 28 and 60). Luminal occlusion was significantly reduced in the combination group compared with the cyclosporine-only group. CONCLUSIONS: Although cyclosporine temporary protects epithelial integrity by the inhibition of acute rejection, rolipram showed greater potency for long-term inhibition of mesenchymal-cell proliferation. The combination of both drugs may be useful for limiting chronic obliterative changes after lung transplantation.

Animals↗
PubMed2001

Closed chest coronary artery bypass on the beating heart.

Minimally invasive surgical procedures have become a part of routine cardiac surgery. The surgical techniques have been developed for the treatment of coronary artery disease in order to minimize surgical trauma. With the introduction of a 3-D-based totally endoscopically functioning system into minimally invasive cardiac (MIC) surgery, further reduction of skin incisions became possible and enhanced MIC techniques could be improved. Due to the 6 degrees freedom of motion allowed by wrist-enhanced instruments and a newly developed endoscopic stabilizer, totally endoscopic coronary artery bypass procedures on a beating heart became feasible. We present here our initial series of totally endoscopic "off-pump" coronary artery bypass grafting in patients suffering from coronary artery single vessel disease. In all patients, the procedure was successfully performed via four 1 cm chest incisions as closed-chest procedures.

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PubMed2000

Closed chest totally endoscopic coronary artery bypass surgery: fantasy or reality?

With the introduction of the da Vinci robotic surgical system (Intuitive Surgical, Mountain View, CA) into minimally invasive cardiac surgery, the outlook of performing coronary artery bypass operations "closed chest" became a reality. Between May 1999 and July 2000 this wrist-enhanced instrumentation was used in 143 patients (107 men, 36 women, median age 63 10.3 y). Thirteen patients suffering from coronary artery disease (CAD) were treated as totally endoscopic coronary artery bypass (TECAB), 79 patients underwent a minimally invasive direct coronary artery bypass procedure, and 35 patients were treated using the robotic-enhanced Dresden Technique. Preoperative survival was 100%. All patients in the TECAB group were operated upon via a three- or four-point stab incision using the da Vinci robot for internal mammary artery takedown and for performance of anastomoses. These new robotic-enhanced surgical techniques promote an optimistic way of thinking about the further development of these procedures and its application in patients suffering from CAD.

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PubMed2000

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.

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PubMed2000

Robotically enhanced "Dresden technique" with bilateral internal mammary artery grafting.

BACKGROUND: A tendency to reduce the operative trauma seems to be the prominent sign of development in cardiac surgery. The combination of the previously introduced minimally invasive "Dresden Technique" with the robotically enhanced endoscopic system enables further progress in coronary artery surgery. METHODS: From May 1999, 25 patients (19 male, 6 female, mean age 63 +/- 8.0 years) suffering from multivessel coronary artery disease (CAD) were treated surgically using arterial revascularization through the bilateral internal mammary arteries (BIMA). Both mammaries were harvested endoscopically using the da Vinci robotic system. Further, the "Dresden Technique" was applied for anastomosis of these vessels with the coronaries. RESULTS: All patients survived the surgery. Mean duration of surgery amounted (244 +/- 82.1 min). BIMA dissection took (87 +/- 18.1 min). An average of 2.2 anastomoses were performed per patient. Postoperatively, the patients remained on ICU for 19 +/- 18 hrs. One patient needed reexploration for bleeding (4%). CONCLUSIONS: The addition of robotically enhanced endoscopic mammary artery harvesting method to the "Dresden Technique" for coronary artery surgery enables the introduction of a new treatment method for CAD into surgical practice, helping to perform an arterial revascularization with a distinctly reduced surgical trauma.

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PubMed2000

Robotic coronary artery surgery--the evolution of a new minimally invasive approach in coronary artery surgery.

BACKGROUND: With the introduction of a wrist-enhanced robotic surgical system into minimally invasive cardiac surgery, the outlook of performing closed chest coronary artery bypass operations became a reality. METHODS: Since May, 1999, this new wrist-enhanced instrumentation has been used in 109 (79 male, 30 female, median age 63 +/- 9.9 years) patients. Seven suffering from single vessel coronary artery disease (SVD) and double vessel disease (DVD) were treated as totally endoscopic coronary artery bypass (TECAB). 60 with SVD underwent a wrist-enhanced, minimally invasive direct coronary artery bypass procedure. 25 with DVD were treated using the robotically enhanced Dresden Technique coronary artery bypass. RESULTS: Survival was 100%. In all patients the IMAs were safely harvested totally endoscopically. In the TECAB group, all patients were operated via a three-point stab incision. Data were observed during and after the operation. CONCLUSIONS: Our preliminary experiences with this new surgical technique for the robotically enhanced, minimally invasive treatment of coronary artery disease promote an optimistic way of thinking about the further development of these procedures.

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PubMed2000

Robotic-enhanced Dresden technique for minimally invasive bilateral internal mammary artery grafting.

BACKGROUND: The introduction of robotic-enhanced endoscopic instrumentation systems allows the surgeon to perform arterial revascularization for multivessel coronary artery disease without sternotomy. METHODS: From April 1999, 27 patients (6 female, 21 male, median age 63 +/- 8.2 years) suffering from multivessel coronary artery disease were treated surgically using arterial revascularization by means of bilateral internal mammary artery (BIMA) grafting. Both arteries were harvested totally endoscopically using the da Vinci robotic surgical system (Intuitive Surgical, Mountain View, CA). These vessels were anastomosed using the "Dresden Technique" via a left minithoracotomy in the second intercostal space. RESULTS: All patients survived the operation. The mean duration of surgery was 240 +/- 79.4 minutes. Bilateral internal mammary artery harvesting time was 88.5 +/- 15.9 minutes, and cross-clamp time was 38 +/- 10.9 minutes. An average of 2.07 anastomoses were performed per operation. Postoperatively, the patients remained in ICU for 20 +/- 2.4 hours. One patient needed reexploration due to bleeding. CONCLUSIONS: Bilateral internal mammary artery harvesting can be achieved safely with the use of wrist-enhanced instrumentation. The robotic surgical system introduces into surgical practice a new type of treatment of coronary artery disease, helping to perform arterial revascularization with a distinctly reduced surgical trauma.

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PubMed1999

New minimally invasive surgical technique using arterial T-grafts for treatment of double-vessel coronary artery disease: experimental study.

Minimally invasive surgery has been used successfully in patients with single-vessel coronary artery disease (CAD), but there are no clinical reports of surgical techniques for the treatment of multivessel disease in this field using both internal mammary arteries (IMAs). Therefore a canine model has been established to demonstrate the feasibility of a minimally invasive surgical treatment of coronary artery double-vessel disease using both IMAs. Ten mongrel dogs underwent bilateral thoracoscopic preparation of both internal mammary arteries through small left lateral chest ports. Using the Port Access endovascular cardiopulmonary bypass system the right IMA (RIMA) was anastomosed as a free graft end-to-side to the left IMA (LIMA) as a T-graft. After induction of cardioplegic arrest the RIMA was anastomosed to the circumflex artery and the LIMA to the left anterior descending artery. All animals were weaned from cardiopulmonary bypass without inotropic support. The electrocardiogram showed sinus rhythm with no signs of ischemia. Intraoperative coronary angiography demonstrated patency of all anastomoses. The minimally invasive surgical treatment of double-vessel CAD using arterial T-grafts of both IMAs is thus feasible. Surgical trauma can be further reduced by harvesting the RIMA transmediastinally through the left lateral chest.

Anastomosis, Surgical↗
PubMed1999

Clinical experience with minimally invasive coronary artery and mitral valve surgery with the advantage of cardiopulmonary bypass and cardioplegic arrest using the Port Access technique.

To minimize surgical trauma, the use of Port Access cardiac surgery was initiated in patients (pts) with coronary artery disease (CAD) (42 pts) or mitral valve disease (MVD) (24 pts) in March 1996 at our institution. Altogether 42 pts (36 men, 6 women; age 31-75 years, median 59.0 years) with isolated lesions of the left anterior descending (LAD) artery underwent Port Access coronary artery surgery (PACAS). A small (5-9 cm) incision was done parasternally on top on the fourth rib. The left internal mammary artery (LIMA) was dissected through the minithoracotomy or by using an additional thoracoscopic approach. A total of 24 pts (12 men, 12 women; age 30-75 years, median 62 years) underwent Port Access mitral valve surgery (PAMVS). In these pts the procedure was performed through a small right thoracotomy (6-8 cm). In all cases, endovascular cardiopulmonary bypass (CPB) was instituted through femoral cannulation, and an additional endoaortic balloon catheter was introduced into the ascending aorta for aortic occlusion. In pts with PACAS the survival was 98% (41/42) and in the PAMVS group 100%. All pts but one survived the PACAS and are well today. There were no deaths in the PAMVS group. The hospital stay was reduced by 1 day on average after PACAS and 3 days after PAMVS. Thus in well selected patients Port Access cardiac surgery represents a safe and feasible minimally invasive surgical approach that avoids the potential complications of a sternotomy while offering the advantages and safety of CPB and cardioplegic arrest. This minimally invasive approach offers a shortened hospital stay and earlier rehabilitation.

Adult↗
PubMed1999

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.

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PubMed1999

Influence of median sternotomy on the psychosomatic outcome in coronary artery single-vessel bypass grafting.

OBJECTIVES: New less invasive surgical techniques for the treatment of coronary artery single-vessel disease have been developed by either avoiding median sternotomy or cardiopulmonary bypass or both, however, until now no prospective randomized trial has been carried out to compare these techniques to the conventional approach with special respect to the psychosomatical effects. METHODS: In a prospective randomized trial four different surgical techniques were compared. Group 1: conventional technique (median sternotomy, cardiopulmonary bypass) in ten patients (eight male, two female, age 59.6 +/- 11.0 years); Group 2: off-pump coronary artery bypass with median sternotomy in nine patients (six male, three female, age 65.7 +/- 11.1 years); Group 3: lateral minithoracotomy and cardiopulmonary bypass in eight patients (five male, three female, age 62.3 +/- 9.9 years). Group 4: off-pump procedure and lateral minithoracotomy in nine patients (eight male, one female, age 63.8 +/- 11.3 years). All patients due to coronary artery single-vessel disease. The tests used for psychosomatic situation were post-traumatic stress disorders scale, pain behavior rating scale, pain visual analog scale, and 6' walking-distance. For detection of false results due to surgical technical failures 3-month follow-up was undertaken including echocardiography and coronary angiogram. RESULTS: There were no deaths or major complications. Operative time was longer in lateral minithoracotomy procedures, but intensive care unit stay and hospitalization were equal in all groups. Pain visual analog scale and pain behavior rating scale showed a peak on post-operative day 4 in median sternotomy procedures. Post-traumatic stress disorder scale revealed higher values on post-operative day 4 and equalizing with lateral minithoracotomy procedures 1 month post-operatively. Six-minutes walking distance on post-operative day 4 was longer in the group with lateral minithoracotomy. Three-month follow-up revealed patency of all grafts. CONCLUSIONS: Even if surgery is successful in all procedures, operative time is longer in lateral minithoracotomy procedures without compromising intensive care unit stay and hospital stay. More pain with multiple post-traumatic stress disorders is related to median sternotomy, and post-operative convalescence is superior for lateral minithoracotomy procedures.

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PubMed1999

Coronary artery bypass grafting via median sternotomy or lateral minithoracotomy.

OBJECTIVES: In order to evaluate the benefit provided through less invasive surgical techniques for the treatment of multivessel coronary artery disease, a prospective clinical trial was started. METHODS: Group 1 included 53 patients (38 males, 15 females, age 51-79 years, mean 62.8 +/- 6.1 years) receiving conventional bypass surgery, group 2 included 69 patients (59 male, 10 female, age 43-82 years, mean 61.9 +/- 8.6 years) receiving less invasive surgical procedure including minithoracotomy in combination with cardiopulmonary bypass. RESULTS: No perioperative death occurred in the whole series of patients. Time of operation was 267 +/- 61 min in group 2 and 162.9 +/- 53.6 min in group 1. Intensive Care Unit stay was 1 day for both groups and Hospitalization 6.9 +/- 6.0 for group 1 and 7.5 +/- 2.6 days for group 2. Perioperative bleeding was less in group 2 (P > 0.01). Back and chest pain assessment on postoperative day 3 showed less pain in group 2 (P < 0.05). Three-month follow-up revealed ischemia in stress electrocardiogram in two patients (3.8%) in group 1 and in 2 patients (2.9%) in group 2. Coronary angiograms confirmed the stress ECG findings. There was one (1.4%) redo operation in group 2 and two (3.8%) in group 1. CONCLUSIONS: Both techniques are equal efficient. Even though time of operation is longer in patients receiving less invasive procedure, intensive care unit stay and hospitalization is exactly as long. Patients receiving minimally invasive surgery bleed less and have less pain early postoperatively.

Adult↗
PubMed1999

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.

Adult↗
PubMed1998

Minimally invasive cardiac surgery for the treatment of coronary artery multi-vessel disease.

OBJECTIVE: In order to avoid sternotomy-related complication after cardiac surgery minimally invasive cardiac surgery has been developed successfully for the treatment of coronary artery disease, however, those techniques were still limited to the treatment of single-vessel disease. Therefore a new surgical technique for the treatment of multi-vessel disease has been developed. METHODS: From November 1996 to May 1997 61 patients (age 39-78 years) with coronary artery disease were treated with this new technique. This technique included a small (6-9 cm) left lateral chest incision via the 3rd intercostal space. The left internal thoracic mammary artery (LIMA) was harvested through the chest incision and access to the central portion of the heart including the ascending aorta was obtained. During LIMA harvesting saphenous vein segments were harvested. Cardiopulmonary bypass was instituted through femoral vein cannulation and cannulation of the ascending aorta in most cases. After external aortic cross clamping cold antegrade cardioplegia was applied. In all patients except one the LIMA was used for the left anterior descending artery (LAD). In addition vein grafts were used for revascularisation of the other coronary arteries. RESULTS: There were no intraoperative complications and all patients survived the procedure. All patients could be weaned from CPB and the postoperative course was uneventful in most patients. Wound complication occurred in two patients. The median hospital stay was 6 days (median +/- SEM). CONCLUSIONS: This new technique combines minimally invasive surgical conditions with the safety standards of routine cardiac surgery. With this approach even extensive coronary artery disease can be treated.

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