Biomedical subjects

Gerhard Wimmer-Greinecker

Publications and source records attributed to Gerhard Wimmer-Greinecker.

At least 37 records · Page 2Linked to original sources

PubMed2005

[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↗

PubMed2004

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↗

PubMed2004

Successful treatment of deep sternal infections following open heart surgery by bilateral pectoralis major flaps.

OBJECTIVES: Severe sternum necrosis requiring extended resection necessitates plastic reconstruction of the resulting defect and stabilization of the chest. We analyzed the outcome of patients undergoing bilateral pectoralis major flap repair on functional and cosmetic results, chest stabilization and pulmonary function. METHODS: Twelve patients undergoing cardiac surgery between 1997 and 2001 suffered from a deep mediastinal wound infection and sternum necrosis. After a mean of two attempts of extensive wound debridement, all 12 patients underwent complete sternal resection with plastic reconstruction by bilateral pectoralis major flaps. Risk factors were obesity (n=10) and diabetes (n=11). Six months postoperatively patients underwent physical examination, pulmonary function testing and functional CT scan. RESULTS: Three patients died in hospital (two septic multiorgan failure, one heart failure) and nine were discharged with complete wound closure. One patient suffered a lethal stroke during follow-up. At 6-month follow-up no recurrent sternum infection had occurred. Chest stability was satisfactory without impairment of pulmonary function (VC 77.5+/-12.1% at follow-up vs 77.8+/-12.5% preoperatively). Mobility and force of arms and shoulder were adequate; at CT scan the maximum distance change between the former sternoclavicular joint in inspiration versus expiration was minimal. Quality of life questionnaires showed no significant limitations except a disturbed sleep and mild restriction of executing hobbies and social activities. CONCLUSIONS: Bilateral pectoralis major flap repair is a safe technique to cure severe mediastinitis necessitating complete sternal resection. Wounds close without extensive reconstructive surgery. Cosmetic results as well as stabilization of the chest were good. Patients reported an almost uncompromised quality of life without respiratory impairment.

Aged↗

PubMed2004

Automatic connector devices for proximal anastomoses do not decrease embolic debris compared with conventional anastomoses in CABG.

OBJECTIVE: Emboli generated during cardiac surgery have been associated with aortic clamping and manipulation. Proximal anastomotic devices are thought to be less traumatic by eliminating partial clamping, potentially resulting in fewer adverse outcomes. Intra-aortic filtration has been shown to effectively capture particulate debris. We compared the amount of debris released using intra-aortic filtration and the clinical outcomes between conventionally handsewn and automated proximal anastomoses. METHODS: Seventy-seven patients undergoing primary coronary artery bypass grafting with cardiopulmonary bypass were enrolled in a prospective randomized study. Patients were assigned to the anastomotic device Group I (Symmetry Aortic Connector, n = 39) or the conventional handsewn anastomosis control Group II (n = 38). Proximal anastomoses were performed before cardiopulmonary bypass in both groups. Intra-aortic Filter 1 (EMBOL-X)was deployed prior to partial clamping or puncturing the aorta for device application and removed after the proximal anastomosis was completed. Prior to cross-clamp removal, a second filter was inserted (Filter 2). A core laboratory performed quantitative and histologic analyses of the debris captured. Clinical outcomes included adverse events, neurocognitive test scores, graft patency, and mortality. RESULTS: Preoperative variables and risk factors were not significantly different between Groups I and II (EuroSCORE 3.9+/-2.6 vs. 4.2+/-2.5). Filter analyses showed no significant difference between Groups I and II in Filter 1 or 2 for either surface area of particles or total number of particles (P> 0.005). There was a significant decrease between Filters 1 and 2 in both Groups for surface area of particles (Group I: 18.5+/-23.8 mm2 vs. 10.7+/-16.3 mm2, P = 0.017; Group II: 15.0+/-15.4 mm2 vs. 6.9+/-.6.5 mm2, P = 0.004), and for total number of particles in Group II (8.6+/-3.7 vs. 7.1+/-2.4, P = 0.023). No significant differences were observed between Group I (device) and Group II (control) outcomes for myocardial infarction, neurocognitive deficit, stroke, length of stay, graft occlusion, or mortality. CONCLUSIONS: The application of proximal aortic connectors without partial clamping does not reduce particulate emboli or affect clinical outcomes compared with conventional anastomoses. Cross-clamping during cardiopulmonary bypass produces less particulate debris than conventional or automated proximal anastomoses performed off-pump, suggesting a major source of emboli is the anastomotic process.

Adult↗

PubMed2004

In vivo inhibition of neutrophil activity by a FAS (CD95) stimulating module: arterial in-line application in a porcine cardiac surgery model.

OBJECTIVE: Cardiac surgery with cardiopulmonary bypass is associated with aberrant neutrophil activation and potentially severe pathogenic sequelae. This experimental study was done to evaluate a leukocyte inhibition module that rapidly inactivates neutrophils through CD95 stimulation. METHODS: German landrace pigs (4 groups, each n = 5) underwent cardiac surgery without cardiopulmonary bypass (group I), with cardiopulmonary bypass (group II), with cardiopulmonary bypass plus a leukocyte filter (group III), and with cardiopulmonary bypass plus a leukocyte inhibition module (group IV). The leukocyte filter or leukocyte inhibition module was introduced into the arterial line of the heart-lung machine. RESULTS: Leukocyte counts were decreased by up to 43% in group IV compared with values in group II (P =.023). In group IV, but not in groups I to III, no delay in spontaneous neutrophil apoptosis was observed after annexin V-propidium iodide staining. Late apoptotic (11.7%) or necrotic neutrophils (9.3%) were detected in 2 animals (group IV). Tumor necrosis factor alpha serum levels increased over time in groups I to III (>2-fold) but remained at baseline levels in group IV (P <.05). Interleukin 8-mediated chemotactic neutrophil transmigration activity increased over time in groups I to III but was totally abrogated in group IV at any time point. The perioperative increase of creatine kinase and creatine kinase MB levels was lower in groups III (1.5-fold and 1.3-fold, respectively) and IV (1.2-fold and 1.5-fold, respectively) compared with values in group II (both 1.9-fold). CONCLUSIONS: The leukocyte inhibition module downregulated cardiopulmonary bypass-related neutrophil activity and thus might be beneficial in cardiac surgery and other clinical settings with unappreciated neutrophil activation.

Animals↗

PubMed2004

Progress in CT imaging for the cardiac surgeon.

The aim of this article is to critically assess the role of multidetector-row CT (MDCT) in the field of cardiothoracic surgery. In the beginning, a short overview is given about technical aspects such as scan protocols, optimal image reconstruction, image reformation techniques, data evaluation, and data presentation. This is followed by sections about possible indications for cardiothoracic surgery and future prospects for this technology. For the cardiac surgeon, the main benefit of MDCT lies in the combination of large scan-volume coverage, high spatial resolution, proper identification of calcifications, and the simultaneous registration of other thoracic structures. Preoperative applications may include the assessment of cardiac valves, noninvasive evaluation of large thoracic vessels, staging of cardiac tumors, and planning of minimally invasive surgical procedures. After surgery, MDCT examinations particularly facilitate an early identification of severe postoperative complications. MDCT may also be used to assess coronary artery bypass graft patency and to identify transplant-related complications in heart transplant recipients at an early stage. New technological developments such as 64-row MDCT or flat panel computed tomography will further increase the field of possible indications.

Coronary Artery Bypass↗

PubMed2004

The Na+/H+ exchange inhibitor HOE642 prevents stress-induced epithelial barrier dysfunction.

Recently, evidence has been obtained that the Na+/H+ exchange (NHE) inhibitor HOE642 may stabilize endothelial and epithelial barrier function in vivo. However, the underlying mechanisms are not known. Therefore, we studied the influence of HOE642 on the barrier function of the epithelial cell line CaCo2. The phorbolester phorbol 12-myristate 13-acetate (PMA) was used to induce hyperpermeability of the epithelial layer which was indirectly determined by measuring the transepithelial electrical resistance (TER). Confocal laser scan microscopy (LSM) served to analyze the intracellular localization of adherens and tight junction molecules. In five independent experiments we found that HOE642 increased TER in non-treated CaCo2 cells (control: 350 +/- 28 Omega/cm2; HOE642: 444 +/- 53 Omega/cm2) and prevented PMA-induced barrier dysfunction (PMA: 33 +/- 12 Omega/cm2; PMA plus HOE642: 496 +/- 47 Omega/cm2). LSM showed that HOE642 prevented the PMA-induced disassociation of the zonula adherens molecule beta-catenin from the cell membrane and the decreased expression of the zonula occludens molecule ZO-1. From our data we conclude that HOE642 may prevent stress-induced epithelial dysfunction by stabilization of cell membrane-associated junction molecules.

Anti-Arrhythmia Agents↗

PubMed2003

Multidetector-row CT: cardiosurgery indications.

This article critically evaluates the role of multidetector-row CT before and after cardiosurgical procedures. In addition, technical aspects, such as scan protocols, optimal image reconstruction intervals, image reformation techniques, and data evaluation, are presented and briefly discussed.

Aortic Valve↗

PubMed2003

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↗

PubMed2003

Emergent endovascular stent grafting for perforated acute type B dissections and ruptured thoracic aortic aneurysms.

BACKGROUND: The purpose of our study was to demonstrate the effectiveness of endovascular stent grafts in the treatment of acutely ruptured thoracic aortic aneurysms and type B dissections as an alternative to the conventional surgical approach in an emergency setting. METHODS: From January 2001 to October 2001, we deployed 11 emergent endovascular stent grafts into the thoracic aorta. We treated seven ruptured aortic aneurysms and four acutely perforated type B dissections. Aortic rupture was confirmed preoperatively by spiral computed tomography. In all cases, hemothorax was present. The average interval from onset of symptoms to treatment was 28.5 hours. We used nine Talent and two Excluder stent grafts. RESULTS: Deployment of the stent grafts was successful in nine cases. There were two cases of access failure due to small caliber of iliac arteries, and 1 of these patients died shortly after the procedure was abandoned, At 12 months of follow-up, there were no cases of paraplegia, stent migration, or endoleaks. There was, however, one temporary renal failure, and 2 patients required mechanical ventilation for more than 48 hours. CONCLUSIONS: Our experiences with emergency endovascular stent grafting show that the procedure is technically feasible, with less morbidity and mortality than conventional open surgery, in high-risk patients.

Adult↗

PubMed2003

Surgical versus endovascular treatment of acute thoracic aortic rupture: a single-center experience.

BACKGROUND: Surgical management of acute thoracic aortic ruptures is controversial, especially in patients with preexisting comorbidities; associated mortality and paraplegia rates remain high. It was our objective to evaluate whether treating these patients acutely with endovascular stent grafts would improve their outcome. METHODS: From November 1999 to February 2002 a total of 54 patients, age 28 to 83 years, were admitted to our institution with an acute rupture of the thoracic aorta (24 ruptured aneurysms, 14 perforated type B dissections, 16 traumatic ruptures). Twenty-eight patients were managed surgically using cardiopulmonary bypass (group 1), and 26 patients were treated acutely with an endovascular stent graft (group 2). The resuscitation protocol and interval from onset of symptoms to treatment was comparable in both groups. Medical records were reviewed for prehospitalization and emergency department data, operative findings, and outcomes. RESULTS: There were 5 of 28 deaths (17.8%) in the surgical group and 1 of 26 deaths (3.8%) in the endovascular group. In the surgical group 1 of 28 patients (3.6%) exhibited paraplegia; there were no cases of paraplegia in the endovascular group. There were 4 of 28 cases (14.3%) of renal failure in group 1 and 1 of 26 (3.8%) in group 2. In group 1, 8 patients (28.6%) required mechanical ventilation for more than 48 hours; there were 2 of 26 patients (7.7%) in group 2 with this ventilatory requirement. Three patients required a repeat thoracotomy for hemorrhage in the surgical group. There were two access failures in the endovascular group. CONCLUSIONS: In the treatment of acute ruptures of the thoracic aorta, the immediate outcome of patients treated with endovascular stent grafts appears to be better than with management by conventional surgical repair.

Adult↗

PubMed2003

Totally endoscopic atrial septal repair in adults with computer-enhanced telemanipulation.

OBJECTIVE: Standard surgical closure of an atrial septal defect via sternotomy is a safe and effective procedure with low morbidity and mortality. Considering that young female patients are frequently operated on for atrial septal defects, a minimally invasive procedure avoiding sternotomy is convincingly desirable and led to the approach through a right anterolateral minithoracotomy. The recent clinical introduction of robotically assisted surgery further reduced skin incisions and enabled totally endoscopic procedures through ports. This article reports on a first series of atrial septal defect closures of which the first case was operated on August 24, 1999, in a totally endoscopic closed chest technique using a computer-enhanced telemanipulation system. METHODS: We performed totally endoscopic atrial septal repair using the da Vinci surgical system (Intuitive Surgical, Mountain View, Calif) in 10 consecutive adult patients. Median age was 45.5 +/- 10.0 years, and preoperative New York Heart Association functional class was 1.8 +/- 0.1. Left ventricular ejection fraction was normal in all patients and mean pulmonary artery pressure amounted to 35 +/- 7 mm Hg. Shunt volume ranged from 24% to 70%. All patients displayed a fossa ovalis type of atrial septal defect; 2 of them multiperforated. RESULTS: Neither intraoperative nor postoperative complications occurred. Two patients had to be converted to minithoracotomy due to endoaortic balloon clamp failure. Length of operation was 262 +/- 37 minutes, and cardiopulmonary bypass time was 161 +/- 26 minutes. Intraoperative transesophageal echocardiography certified complete closure of the atrial septal defect in all patients. The totally endoscopic computer-enhanced technique yielded excellent cosmetic results. CONCLUSION: Totally endoscopic atrial septal repair is a feasible and safe procedure with good clinical results and excellent cosmetic outcomes. It may be considered as perfect adjunct to interventional treatment options. Further studies with larger cohorts and randomized trials are necessary to document potential benefits. Evolution in robotic technology and refinement of procedural flow may shorten procedural time and decrease costs.

Adult↗

PubMed2003

Facilitated endoscopic beating heart coronary artery bypass grafting using a magnetic coupling device.

BACKGROUND: Suturing of a coronary anastomosis in totally endoscopic coronary artery bypass grafting on the beating heart is technically demanding. The potential benefits of the endoscopic Magnetic Vascular Positioner device (Ventrica, Inc, Fremont, Calif) to facilitate construction of a coronary anastomosis in a closed chest environment were evaluated. METHODS: Totally endoscopic coronary artery bypass grafting on the beating heart was performed in 8 foxhound-beagle inbred dogs with the da Vinci telemanipulation system (Intuitive Surgical, Mountain View, Calif). A prototype of the endoscopic Magnetic Vascular Positioner device was used to facilitate construction of the coronary anastomosis. One pair of magnets was inserted in the internal thoracic artery and left anterior descending artery using robotic instruments to guide and place the endoscopic delivery platform. All animals underwent angiography; gross inspection of the anastomotic site was performed after excision of the hearts. RESULTS: The procedure was accomplished in all animals in 169 minutes (155-190 minutes). Dissection of the left anterior descending coronary artery (6.5 minutes; 1-20 minutes), positioning of the stabilizer (8.5 minutes; 7-16 minutes), placement of occlusion tapes (6 minutes, 3-10 minutes), and arteriotomy 5.5 minutes (3-30 minutes) was achieved without problems. By use of the Magnetic Vascular Positioner device, the anastomosis at the graft site was performed with the graft still in situ. Except for 1 premature deployment, all other deployments were easily accomplished in 3 minutes (1-28 minutes). The following adverse events were encountered: bleeding from the right ventricle caused by occlusion tape (1), anastomotic leakage on reperfusion requiring repair stitches (2), and anastomotic occlusion as a result of thrombus (1). All except 1 animal with a patent graft and anastomosis survived the procedure. The overall patency was 7 of 8. DISCUSSION: The combination of robotic technology allowing for dexterous manipulation in a closed chest environment and a simple yet effective and timesaving technique for anastomotic coupling may facilitate beating heart totally endoscopic coronary artery bypass grafting.

Anastomosis, Surgical↗

PubMed2003

Magnetic vascular coupling for distal anastomosis in coronary artery bypass grafting: a multicenter trial.

OBJECTIVE: The hand-sewn anastomosis is the "gold standard" for performing coronary artery bypass grafts. However, performing a hand-sewn anastomosis is more demanding and time-consuming when used in less invasive approaches such as small access, totally endoscopic or beating heart surgery. In conjunction with attempts to reduce the surgical trauma of coronary artery bypass grafts by using these less invasive approaches, alternative methods for constructing distal anastomoses should be explored. These data report on predischarge angiographic findings and 30-day clinical follow up of patients who have received a new distal anastomotic device. METHODS: In a multicenter trial, 32 patients (mean age: 65 +/- 9 years; 85% men) requiring multivessel coronary artery bypass surgery had 1 of the anastomoses performed using a novel anastomotic technology. The Magnetic Vascular Positioner System was used in 1 of the bypass grafts and the other bypasses were completed by conventional hand-sewn technique. The Magnetic Vascular Positioner System consists of 4 magnetic, gold-plated implants and 2 delivery devices that facilitate the creation of a functional end-to-side anastomosis. A predischarge angiogram was performed to evaluate graft patency. RESULTS: There were no device-related major adverse events. The application of the Magnetic Vascular Positioner device was successful in 32 of 41 cases (78%). Nine patients were intended for treatment but did not receive the Magnetic Vascular Positioner System. In 5 of the cases the coronary artery was too small; 1 case had a posterior wall plaque in the target artery; and 3 patients had a nonhemostatic anastomosis after coupling of the port and were subsequently converted to hand-sewn anastomoses. The median total Magnetic Vascular Positioner anastomotic time was 137 seconds with a range from 65 to 370 seconds. Overall patency rate of the Magnetic Vascular Positioner anastomosis was 93.5% versus 91.7% (P = not significant) in hand-sewn grafts. One patient (3.1%) died due to low cardiac output but had patent grafts at autopsy. One myocardial infarction (3.1%) occurred the day after a percutaneous transluminal coronary angioplasty of a hand-sewn graft. One prolonged mechanical ventilation (3.1%) was required because of pneumonia and adult respiratory distress syndrome. CONCLUSIONS: Magnetic vascular coupling in coronary surgery is safe and effective and has acceptable early patency rates. This new technique may facilitate beating heart and minimally invasive coronary artery bypass grafts.

Adult↗

PubMed2003

Reduction of neurologic complications by intra-aortic filtration in patients undergoing combined intracardiac and CABG procedures.

OBJECTIVE: Patients undergoing combined intracardiac and coronary artery bypass grafting (CABG) procedures are at high risk for neurologic events. Previously the Multicenter Study of Perioperative Ischemia (McSPI) Study Group demonstrated that risk factors for neurologic complications in these patients related primarily to embolization. OBJECTIVE: This study investigated risk factors and outcomes in 185 high-risk patients receiving intra-aortic filtration during combined intracardiac and CABG procedures. METHODS: Seventeen European centers comprising the International Council of Emboli Management (ICEM) pooled data on patients receiving intra-aortic filtration (EMBOL-X, Mountain View, CA, USA) into a consecutive enrollment registry. Preoperative, intraoperative, and outcome variables were compared between ICEM patients undergoing combined CABG and intracardiac procedures and the corresponding McSPI subgroup. RESULTS: Type I outcomes (stroke, transient ischemic attack, coma, death due to neurologic causes) occurred in 2.2% (4/185) of ICEM patients compared to 8.4% (23/273) of McSPI patients. No ICEM patient suffered a fatal stroke compared with five in the McSPI study (1.8%). One nonfatal stroke was observed in the ICEM group (0.5%) and 16 were observed in the McSPI group (5.9%). Three patients (1.6%) were reported with transient ischemic attack in the ICEM group, compared to two in the McSPI study (0.7%). One of the reported patients in the ICEM group with transient ischemic attack also suffered a coma that was still evident at discharge. In all, four patients suffered Type I neurologic events in the ICEM group (2.2%), compared to 23 in the McSPI group (8.4%). In the ICEM study group, four patients (2.2%) died due to non-neurologic causes, compared to 18 in the McSPI group (6.6%). CONCLUSIONS: Even with a significantly worse preoperative profile, high-risk patients receiving intra-aortic filtration suffered Type I cerebral injury 74% less often than patients in the McSPI group.

Aged↗

PubMed2003

Cariporide (HOE642) limits S-100B release during cardiac surgery.

Cardiac surgery with cardiopulmonary bypass (CPB) results in transient cerebral swelling in most patients. Cognitive decline occurs in 24-57% of patients and 2-5% experience stroke. Serum levels of S-100B, a potential marker of increased blood-brain barrier permeability, increase during and early after surgery. The authors studied the effects of the novel Na /H exchange inhibitor cariporide (HOE642) on postoperative serum levels of S-100B and neuron-specific enolase (NSE) in 53 patients at high risk undergoing coronary artery bypass grafting. Patients were randomly assigned to one of four groups: I, placebo; II, 20 mg cariporide; III, 80 mg cariporide; IV, 120 mg cariporide). In addition, the leukocyte activation marker myeloperoxidase (MPO) and malondialdehyde (MDA), a marker for lipid peroxidation, were evaluated by enzyme-linked immunoassay. Postoperatively, five patients experienced transient ischemic attack or stroke. S-100B levels increased from 0.43 microg/l +/- 0.33 before operation to 2.27 microg/l +/- 0.69 1 hour after surgery in the placebo group. Preoperative S-100B levels in the HOE642 groups did not differ from the placebo group whereas, 1 hour after surgery, levels were significantly lower in groups II, III, and IV (1.63 microg/l +/- 0.2, 1.27 microg/l +/- 0.27, and 0.90 microg/l +/- 0.21, respectively). NSE, MPO, and MDA serum levels did not differ among groups. These findings may stimulate larger clinical studies to examine the effects of HOE642 on cerebral swelling and neurologic/cognitive outcome of cardiac surgery with CPB.

Aged↗

PubMed2003

Totally endoscopic multivessel coronary artery bypass surgery using the da Vinci surgical system: a feasibility study on cadaveric models.

BACKGROUND: The aim of the study was to develop a totally endoscopic coronary artery bypass procedure for the treatment of multivessel disease (MVTECAB). METHODS: Procedure development was conducted on 6 human cadavers with the da Vinci Surgical System. For aortic clamping, a transthoracic aortic clamp was applied. The proximal anastomoses of vein grafts were created transthoracically with the Corlink automated anastomosis device. The target vessels on the heart were exposed with a modified endoscopically applicable Starfish vacuum device. In 1 cadaver, the endo-sling and endoscopic fan retractors were studied for exposure support. RESULTS: Harvesting of bilateral internal thoracic arteries was easily accomplished. Aortic clamping was easier from the right side. In the left-side approach, the proximal anastomoses were completed without leakage in all 3 cadavers. One incorrect deployment occurred, and the deployment needed to be redone. In the right-si d e approach, 1 proximal anastomosis was performed without leakage, and another needed to be repaired for incorrect deployment. The fan retractors either covered too much of the targeted area of the heart surface or did not provide good manipulation capabilities. The endo-sling enabled atraumatic exposure of the target vessels. The modified Starfish performed sufficiently for exposing target vessels. Problems were found with epicardial fat clogging the Starfish suction chamber and with bending of the suction tube neck, both of which resulted in a loss of tissue contact. Two of the cadavers approached from the left side were completely revascularized with 3 grafts, and 4 anastomoses were performed on the third cadaver. Triple-vessel revascularization was performed in the cadavers approached from the right side. CONCLUSION: This study demonstrates the feasibility of performing an MVTECAB on the arrested heart with the da Vinci Surgical System. Further procedure development is necessary to optimize the synergistic effects of the technologies used and to introduce this operation into clinical practice.

Cadaver↗

PubMed2003

Minimally invasive versus conventional aortic valve replacement: a prospective randomized trial.

BACKGROUND AND AIM OF THE STUDY: A prospective randomized study was performed to compare conventional with minimally invasive aortic valve replacement (AVR). METHODS: Forty consecutive patients scheduled for elective aortic valve surgery were prospectively randomized either to the conventional group (group A, complete median sternotomy) or minimally invasive group (group B, partial upper sternotomy). Intraoperative and postoperative clinical data, and markers of myocardial and cerebral protection were determined. Neuropsychological tests were carried out to quantify psychological disorders. RESULTS: Operative time and cardiopulmonary bypass time were slightly longer in group B, but not significantly so. No significant inter-group differences were found for postoperative pain scores and respiratory function. Chest tube drainage was significantly less in group B (495 +/- 165 versus 240 +/- 69 ml, p = 0.008). Creatine kinase (CK), CK-MB and troponin T levels were similar in both groups. Neither S-100B protein nor neuron-specific enolase levels differed significantly between groups at all sampling times. There were no strokes in the entire cohort. None of the neuropsychological tests yielded significant inter-group differences between conventional and minimally invasive surgery. CONCLUSION: The safety and reliability of AVR via a partial upper sternotomy is reported. Minimally invasive AVR can be performed with only slightly longer operative times, good cosmetic results and significantly less blood loss. A limited surgical access affected neither the patients' neurological outcome nor the efficacy of myocardial protection.

Aortic Valve Insufficiency↗