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T Schachner

Publications and source records attributed to T Schachner.

10 recordsLinked to original sources
PubMed2006

Technical challenges in totally endoscopic robotic coronary artery bypass grafting.

OBJECTIVE: Robotic technology is a prerequisite for performance of totally endoscopic coronary artery bypass grafting. During the implementation phase of totally endoscopic coronary artery bypass, surgeon-related technical difficulties might be encountered. It was the aim of this study to assess the incidence of these challenges, to find risk factors, and to describe clinical results associated with technical errors. METHODS: From October 2001 through October 2004, 40 patients received robotically assisted totally endoscopic left internal thoracic artery grafts to the left anterior descending coronary artery system with the da Vinci telemanipulation device. All patients underwent remote access cardiopulmonary bypass perfusion through groin access, and all anastomoses were performed on the arrested heart. RESULTS: Undesirable technical events of various grades occurred in 20 (50%) of 40 patients: bleeding from a port hole in 3 (8%), left internal thoracic artery damage in 3 (8%), epicardial lesion in 3 (8%), remote access perfusion problems in 9 (23%), bleeding from the anastomosis in 4 (10%), and anastomotic stenosis in 2 (5%). There was no hospital mortality. The following differences were noted between patients without technical difficulties (group 1) and those in whom problems occurred (group 2): total operative time of 314 minutes (260-540 minutes) versus 418 minutes (270-690 minutes; P = .007), ventilation time of 6 hours (0-26 hours) versus 14 hours (0-278 hours; P = .004), intensive care unit stay of 20 hours (11-70 hours) versus 44 hours (16-336 hours; P=.183), hospital stay of 7 days (4-13 days) versus 8 days (5-21 days; P = .038), and cumulative freedom from angina at 36 months of 93% versus 100% (P = .317). CONCLUSION: We conclude that technical difficulties during totally endoscopic coronary artery bypass grafting translate into markedly increased operative time, moderately prolonged postoperative ventilation time, and slightly increased hospital stay. Short-term survival and freedom from angina, however, do not seem to be compromised.

Adult↗
PubMed2005

Ongoing procedure development in robotically assisted totally endoscopic coronary artery bypass grafting (TECAB).

BACKGROUND: Totally endoscopic coronary artery bypass grafting (TECAB) using robotics requires stepwise introduction into a heart surgery program. It is the aim of this study to evaluate the state of procedure development after continued application of telemanipulation techniques in the clinical setting. We also sought to assess perioperative and intermediate term clinical results after robotically assisted CABG. PATIENTS AND METHODS: From June 2001 to March 2005, robotically assisted CABG using the daVinci system was carried out in 107 patients with single and multi-vessel coronary artery disease. The following procedures were performed: robotically assisted endoscopic left internal mammary artery (LIMA) harvesting and completion of the procedure as conventional CABG, MIDCAB, or OPCAB (n = 22), robotically assisted suturing of LIMA-to-LAD anastomoses during conventional CABG (n = 28), TECAB on the arrested heart using remote access perfusion (n = 48), TECAB on the beating heart using an endostabilizer (n = 8), takedown of adhesions (TECAB intended) (n = 1). RESULTS: Hospital mortality was 0% and cumulative risk adjusted mortality reached 1.6 lives saved versus EuroSCORE predictions. Undesirable surgical events (USE) such as conversion, on table revision, or postoperative revision procedures occurred in 34 out of 107 (32%) patients. Median ventilation time and ICU stay, however, were 11(0-278) hours and 21(11-389) hours, respectively. Cumulative 3 years survival was 100% and freedom from angina at 3 years was 97%. CONCLUSIONS: We conclude that despite being surgically challenging robotically assisted coronary artery surgery can be implemented with acceptable safety. TECAB procedures have reached a reproducible state. Perioperative mortality after robotically assisted CABG may be lower than predicted. Intermediate term clinical results are very satisfactory.

Adult↗
PubMed2005

Treatment of double vessel coronary artery disease by totally endoscopic bypass surgery and drug-eluting stent placement in one simultaneous hybrid session.

Hybrid coronary artery revascularization is a combination of minimally invasive coronary artery surgery and catheter-based coronary intervention. Hybrid procedures enable adequate revascularization of patients with multivessel coronary artery disease without complete opening of the chest and with the advantage of the most durable option, a left internal mammary artery (LIMA) graft is placed to the left anterior descending (LAD) artery. The hybrid concept is gaining renewed interest because totally endoscopic LIMA to LAD placement has become feasible and because drug-eluting stents in non-LAD targets may be competitive even for arterial bypass grafts. Simultaneous hybrid procedures would be desirable. We report on a case in which robotic totally endoscopic LIMA to LAD grafting using the da Vinci telemanipulation system was combined with placement of a rapamycin coated stent to the right coronary artery in one single procedure.

Aged↗
PubMed2005

Factors associated with mortality and long time survival in patients undergoing modified Bentall operations.

AIM: We report our results on mortality, morbidity and long time events after composite graft replacement of the aortic root and ascending aorta/aortic arch and factors associated with them. METHODS: Seventy-four patients, aged 52 years (15-73) underwent modified ''button'' Bentall operation. The indication for operation was acute dissection in 29 (39%) patients, chronic dissection in 3 (4%), aortic regurgitation after previous replacement of the ascending aorta because of aortic dissection in 2 (3%) and non dissecting aneurysm in 40 (54%). Concommitant procedures were (partial) replacement of the aortic arch in 11 (15%) and coronary artery bypass grafting in 5 (7%). Six patients (8%) had undergone previous cardiac surgery. Mean follow up was for 49 +/- 46 months (maximum 198). RESULTS: Length of intensive care unit (ICU) stay was 3 days (1-72). Hospital mortality was 12%. Factors significantly associated with hospital mortality were: aortic dissection, cardiopulmonary bypass time, aortic cross clamp time, deep hypothermic circulatory arrest, low cardiac output syndrome, revision due to bleeding, renal failure requiring hemofiltration, multisystemic organ failure and sepsis. None of these factors was significantly associated with long term survival. Survival rates including hospital deaths were 86%, 84%, 75% and 75% after 1, 3, 5 and 7 years respectively. Pseudoaneurysm at the composite graft occurred in 3%, infection of the prosthesis in 1%. Neither valve thrombosis nor thromboembolic events occurred postoperatively. CONCLUSIONS: Modified Bentall operation is a demanding operation with acceptable hospital mortality. The long time survival rates are good and the big majority of patients is eventfree after operation.

Adolescent↗
PubMed2004

Combined transplantation of skeletal myoblasts and bone marrow stem cells for myocardial repair in rats.

OBJECTIVES: To prove whether intramyocardial transplantation of combined skeletal myoblasts (SM) and mononuclear bone marrow stem cells is superior to the isolated transplantation of these cell types after myocardial infarction in rats. METHODS: In 67 male Fischer rats myocardial infarction was induced by direct ligature of the LAD. Seven days postinfarction baseline echocardiography and intramyocardial cell transplantation were performed. Via lateral thoracotomy 200 microl containing either 10(7) SMs or 10(7) bone marrow-derived mononuclear cells (BM-MNC) or a combination of 5x10(6) of both cell types (MB) were injected in 10-15 sites in and around the infarct zone. In controls (C) 200 microl of cell-free medium were injected in the same manner. Before injection both cell types were stained using a fluorescent cell linker kit (PKH, Sigma). In addition, SMs were transfected with green fluorescent protein. Nine weeks postinfarction follow-up echocardiography was performed and animals were sacrificed for further analysis. RESULTS: At baseline echocardiography there was no difference in left ventricular ejection fraction (LVEF; C, SM, BM-MNC, MB: 60.1+/-3.2, 53.3+/-10.2, 53.1+/-8.7, 49+/-9.0%) and left ventricular end diastolic diameter (LVEDD; C, SM, BM-MNC, MB: 6.5+/-0.8, 5.17+/-0.8, 5.77+/-1.4, 6.25+/-0.8 mm) between the different therapeutic groups. Eight weeks after cell transplantation LVEDD was significantly increased in all animals except those that received a combination of myoblasts and bone marrow stem cells (MB; C, SM, BM-MNC, MB: 7.7+/-0.6 mm, P=0.001; 7.7+/-1.5 mm, P<0.001; 7.7+/-1.1 mm, P=0.005; 6.6+/-1.7 mm, P=0.397. At the same time LVEF decreased significantly in the control group (C), stayed unchanged in animals that received bone marrow stem cells (BM-MNC) and increased in animals that received myoblasts (SM) and a combination of both cell types (MB; C, SM, BM-MNC, MB: 45.3+/-7.0%, P=0.05; 63.9+/-15.4%, P=0.044; 54.3+/-6.3%, P=0.607; 63.0+/-11.5%, P=0.039). CONCLUSIONS: The present data show that the concept of combining SMs with bone marrow-derived stem cells may be of clinical relevance by merging the beneficial effects of each cell line and potentially reducing the required cell quantity. Further studies are required to identify the exact mechanisms underlying this synergy and to allow full exploitation of its therapeutic potential.

Animals↗
PubMed2004

Robotic totally endoscopic coronary artery bypass: program development and learning curve issues.

BACKGROUND: The introduction of new procedures in heart surgery is a critical phase that includes learning curves and the risk of increased mortality or morbidity. Totally endoscopic coronary artery bypass grafting using robotic techniques represents such an innovative procedure. The aim of this report is to demonstrate the safe introduction of totally endoscopic coronary artery bypass grafting using a stepwise and modular approach. METHODS: From June 2001 until December 2002, 50 procedures were performed using the da Vinci telemanipulator system. After baseline training the following procedure modules were carried out in a stepwise manner: robotically assisted endoscopic left internal thoracic artery harvesting and completion of the procedure as conventional coronary artery bypass grafting, minimally invasive direct coronary artery bypass, or off-pump coronary artery bypass (n = 19), robotically assisted suturing of left internal thoracic artery to left anterior descending anastomoses during conventional coronary artery bypass grafting (n = 15), totally endoscopic coronary artery bypass grafting on the arrested heart using remote access perfusion and aortic endocclusion coronary bypass grafting (n = 15). One patient was excluded intraoperatively from a robotic procedure due to pleural adhesions. RESULTS: A significant learning curve was observed for left internal thoracic artery takedown time, y(min) = 181 - 39 x ln(x) (x = procedure number) (P <.001), and total operative time in totally endoscopic coronary artery bypass grafting, y(min) = 595 - 87 x ln(x) x = (procedure number) (P =.028). The conversion rate in totally endoscopic coronary artery bypass grafting was 2/15. Intensive care unit stay correlated significantly with total operative time (r =.427, P =.002). There was no hospital mortality. CONCLUSION: Totally endoscopic coronary artery bypass grafting can be safely implemented into a heart surgery program. Learning curves are steep for robotic left internal thoracic artery takedown and for performance of totally endoscopic coronary artery bypass grafting. Long operative times translate into prolonged intensive care unit stay in specific cases but not into increased mortality.

Adult↗
PubMed2004

Is the axillary artery a suitable cannulation site in aortic surgery?

AIM: The axillary artery is currently gaining interest as an alternative to femoral artery cannulation in aortic surgery. It was the aim of our study to evaluate the feasibility, safety, and efficacy of axillary artery cannulation in a series of patients undergoing surgery of the ascending aorta and/or the aortic arch. METHODS: From 1998 to 2002 cardiopulmonary bypass (CPB) perfusion via the axillary artery was intended in 35 patients (28 male), median age 61 (22-77) years. The underlying disease was acute aortic dissection type A in 22/35 (63%), chronic aortic dissection type A in 2/35 (6%), ascending aortic aneurysm in 8/35 (22%), aortic regurgitation after previous ascending aortic replacement in 1/35 (3%), pseudoaneurysm after Bentall operation in 1/35 (3%) and coronary artery disease with severe arteriosclerosis of the aorta in 1/35 (3%). RESULTS: Conversion to femoral artery or ascending aortic cannulation was necessary in 3 patients. In the other cases, adequate CPB flows of 2.4 l/m2/min were achieved. In 1 case local dissection of the axillary artery occurred after emergency cannulation. No postoperative complications related to axillary artery cannulation, such as upper extremity ischemia, brachial plexus injury, or local wound infection occurred. No new postoperative stroke was noted, hospital mortality was 4/35 (11%) patients. CONCLUSION: Axillary artery cannulation is feasible in the majority of cases and seems to be a safe and effective method in surgery of the ascending aorta and aortic arch. Several disadvantages of femoral artery cannulation and perfusion can be avoided.

Adult↗
PubMed2004

A variation of the radial artery and its clinical implications for coronary artery bypass grafting.

Since the radial artery is increasingly harvested as a bypass graft, surgeons are confronted with its anatomical variations. We report on a radial artery running laterally around the distal part of the radius, while a superficial palmar branch is running straight down. The radial artery can be dissected distally to get enough length for the bypass graft, but attention has to be paid to the superficial branch of the radial nerve running nearby to prevent postoperative paresthesias and numbness. The superficial palmar branch of the radial artery can be ligated. Allen's test in such a case is not valid because it is always negative.

Aged↗