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1.
Exp Cell Res ; 313(11): 2326-35, 2007 Jul 01.
Article in English | MEDLINE | ID: mdl-17475245

ABSTRACT

Recent data suggest that angiogenesis plays an important role in the pathogenesis of valvular disease. However, the cellular mechanisms underlying this process remain unknown. This study aimed at identifying and characterizing the cellular components responsible for pathological neovascularization in calcific aortic valves (CAV). Immunohistochemical analysis of uncultured CAV tissues revealed that smooth muscle alpha-actin (alpha-SMA)-positive cells, which coexpressed Tie-2 and vascular endothelial growth factor receptor-2 (VEGFR-2), can be identified prior to the initiation of capillary-like tube formation. In a second step, leaflets of CAV and non-calcific aortic valves (NCAV) were cultured and the cells involved in capillary-like tube formation were isolated. The majority of these cells displayed the same phenotype as non-cultured cells identified in CAV tissues, i.e., expression of alpha-SMA, Tie-2, and VEGFR-2. In comparison to cells isolated from cultures of NCAV leaflets, these cells showed enhanced angiogenic activity as demonstrated by migration and tube assays. The coexpression of VEGFR-2 and Tie-2 together with alpha-SMA suggests both endothelial and mesenchymal properties of the angiogenically activated cells involved in valvular neovascularization. Hence, our findings might provide new insights into the process of pathological angiogenesis in cardiac valves.


Subject(s)
Aortic Valve Stenosis/pathology , Aortic Valve/pathology , Neovascularization, Pathologic/pathology , Actins/metabolism , Antigens, CD/analysis , Aortic Valve/chemistry , Aortic Valve/metabolism , Aortic Valve Stenosis/genetics , Aortic Valve Stenosis/metabolism , Biological Assay , Cells, Cultured , Chemotaxis , Female , Flow Cytometry , Humans , Male , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/metabolism , Organ Culture Techniques , Phenotype , Receptor, TIE-2/metabolism , Transcription, Genetic , Vascular Endothelial Growth Factor A/pharmacology , Vascular Endothelial Growth Factor Receptor-2/metabolism
2.
J Card Surg ; 21(4): 386-90, 2006.
Article in English | MEDLINE | ID: mdl-16846418

ABSTRACT

AIM OF THE STUDY: Atrial fibrillation (AF) commonly occurs following open heart surgery especially in the high-risk group of old patients with reduced left ventricular function. Via Syncrus heart wires implanted on the left and right atrium internal cardioversion shocks can be applied. This prospective nonrandomized multicenter study compares duration of AF periods and clinical outcome in patients treated with Syncrus wires to a control group treated conventionally. METHODS: In 88 patients Syncrus heart wires were implanted. Upon detection of AF antiarrhythmic medication was started for at least 6 hours followed by internal cardioversion. The results of this treatment were compared to a control group of 86 patients with an identical risk profile. RESULTS: In the Syncrus group 53.4% of patients suffered from postoperative AF compared with 50.0% in the control group. Internal cardioversion led to restoration of sinus rhythm in 60% of patients at the first series of shocks (mean energy 7.7 +/- 1.3 J) and 95.8% with the second series (mean energy 8.6 +/- 0.5 J). Length of AF periods was 12.4 +/- 7.2 hours in the Syncrus group versus 42.9 +/- 19.6 hours in control patients. CONCLUSIONS: Internal cardioversion using Syncrus heart wires demonstrated effectiveness in treating postoperative AF. Especially, length of AF periods could be diminished by the system with the expectation of reduction in hospital length of stay.


Subject(s)
Atrial Fibrillation/therapy , Cardiac Surgical Procedures/adverse effects , Electric Countershock , Aged , Aged, 80 and over , Anti-Arrhythmia Agents/therapeutic use , Atrial Fibrillation/drug therapy , Atrial Fibrillation/etiology , Cardiac Pacing, Artificial , Defibrillators, Implantable , Electric Countershock/instrumentation , Equipment Design , Female , Hospital Mortality , Humans , Male , Prospective Studies , Treatment Outcome
3.
Med Oncol ; 23(1): 23-36, 2006.
Article in English | MEDLINE | ID: mdl-16645227

ABSTRACT

Iron balance is regulated by the rate of erythropoiesis and the size of the iron stores. Anemia that accompanies infection, inflammation, and cancer (anemia of chronic disease) features normal or increased iron stores, although patients may have functional iron deficiency, namely, an imbalance between iron requirements of the erythroid marrow and the actual supply. The proportion of hypochromic red cells and the hemoglobin content of reticulocytes are direct indicators of functional iron deficiency. Biochemical markers, especially the soluble transferrin receptor/log ferritin ratio (ferritin index), are useful indicators of the iron supply to erythropoiesis. The relationship between functional iron deficiency (reticulocyte hemoglobin content) and iron supply to erythropoiesis (ferritin index) can be described in a diagnostic plot. In normoproliferative and hypoproliferative erythropoiesis, the plot allows the differentiation of classic iron deficiency from anemia of chronic disease and the combined state of functional iron deficiency with anemia of chronic disease. The therapeutic implications of the plot are to differentiate patients into those who should be administered iron supplements, epoetin, or a combination of epoetin and iron. In patients receiving epoetin therapy, the plot is an important tool for monitoring erythropoietic activity, functional iron deficiency, and adequate iron stores for new red cell production. Enhanced erythropoiesis is reflected quantitatively by the ferritin index vector. A transgression of the 1.5 (3.2) cut-off value for the ferritin index indicates that extra doses of iron need to be administered to increase the body's iron stores. A lack of increase or a reticulocyte hemoglobin content below 28 picograms indicates functional iron deficiency. The diagnostic plot is a model for differentiating iron-deficient states and predicting those patients who will respond to epoetin therapy.


Subject(s)
Anemia, Iron-Deficiency/diagnosis , Erythropoietin/therapeutic use , Iron Deficiencies , Biomarkers , Epoetin Alfa , Erythropoiesis , Humans , Iron/metabolism , Recombinant Proteins
4.
IEEE Trans Biomed Eng ; 52(10): 1729-40, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16235658

ABSTRACT

Minimally invasive beating-heart surgery offers substantial benefits for the patient, compared to conventional open surgery. Nevertheless, the motion of the heart poses increased requirements to the surgeon. To support the surgeon, algorithms for an advanced robotic surgery system are proposed, which offer motion compensation of the beating heart. This implies the measurement of heart motion, which can be achieved by tracking natural landmarks. In most cases, the investigated affine tracking scheme can be reduced to an efficient block matching algorithm allowing for realtime tracking of multiple landmarks. Fourier analysis of the motion parameters shows two dominant peaks, which correspond to the heart and respiration rates of the patient. The robustness in case of disturbance or occlusion can be improved by specially developed prediction schemes. Local prediction is well suited for the detection of single tracking outliers. A global prediction scheme takes several landmarks into account simultaneously and is able to bridge longer disturbances. As the heart motion is strongly correlated with the patient's electrocardiogram and respiration pressure signal, this information is included in a novel robust multisensor prediction scheme. Prediction results are compared to those of an artificial neural network and of a linear prediction approach, which shows the superior performance of the proposed algorithms.


Subject(s)
Artificial Intelligence , Heart/physiopathology , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Movement , Myocardium/pathology , Surgery, Computer-Assisted/methods , Algorithms , Electrocardiography/methods , Humans , Myocardial Contraction , Robotics/methods
5.
Ann Thorac Surg ; 79(2): 485-90; discussion 490-1, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15680820

ABSTRACT

BACKGROUND: In order to assess different surgical techniques for video-assisted minimally invasive mitral valve surgery, a retrospective study was undertaken comparing the Port-Access system (Cardiovations, Ethicon Inc, Somerville, NJ) and the transthoracic clamp technique. METHODS: In 120 patients mitral valve surgery was performed through a small right minithoracotomy using either the Port-Access endovascular cardiopulmonary bypass system (Port-Access, n = 60) or the transthoracic clamp technique (MICRO, n = 60). Mean patient age was 61.5 +/- 10.5 years (81 patients with isolated mitral valve insufficiency, 39 patients with combined mitral valve disease). RESULTS: Eighty-one (67.5%) patients underwent mitral valve repair and 39 (32.5%) patients had valve replacement. Mean time of surgery was 4.5 +/- 3.5 and 4.1 +/- 3.2 hours (p = 0.07), aortic cross-clamp time 89 +/- 69 and 78 +/- 65 minutes (p = 0.08), mean intensive care unit stay 1.5 +/- 2.1 and 1.6 +/- 2.5 days (p = ns), and hospital stay 9.0 +/- 10.5 and 9.2 +/- 9.7 days (p = ns) in the Port-Access and MICRO groups, respectively. In the Port-Access group, there were 6 reexplorations for bleeding, one perforation of the right ventricle with the endopulmonary vent, and 2 reconstructions of the femoral artery necessary after femoral cannulation, compared to one reexploration for bleeding in the MICRO group. There was only one minor paravalvular leak after replacement and 2 cases of residual greater than or equal to grade II mitral valve regurgitation after mitral valve repair in the Port-Access group, necessitating reoperation. In both groups, there was no mortality, no cerebrovascular accident, no aortic dissection, and no conversion to sternotomy. CONCLUSIONS: Minimally invasive mitral valve surgery has become a standard approach for isolated mitral valve operations at our institution. The MICRO technique tends to shorten the time of surgery and aortic cross-clamping and reduces perioperative costs by simplifying the operative procedure.


Subject(s)
Catheters, Indwelling , Mitral Valve Insufficiency/surgery , Mitral Valve/surgery , Robotics/methods , Thoracotomy/methods , Video-Assisted Surgery/methods , Cardiopulmonary Bypass , Female , Humans , Length of Stay , Male , Middle Aged , Mitral Valve Insufficiency/mortality , Retrospective Studies , Survival Rate , Treatment Outcome , Video-Assisted Surgery/adverse effects
6.
Crit Care Med ; 32(8): 1662-8, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15286541

ABSTRACT

OBJECTIVE: An initial phase II trial to investigate the safety and therapeutic effect of the endotoxin adsorber system EN 500 in septic patients suffering from presumed Gram-negative infection. DESIGN: Open, controlled, prospective, randomized, multiple-center, parallel-group clinical trial. SETTING: Intensive care units of 31 university-affiliated and community hospitals in Europe. PATIENTS: One hundred forty-five patients with a clinical diagnosis of severe sepsis or septic shock due to suspected Gram-negative infection. INTERVENTIONS: Patients were randomized to receive either standard therapy alone for sepsis (n = 76) or standard therapy plus extracorporeal endotoxin adsorption (n = 67) daily for the first 4 days following study entry. MEASUREMENTS AND MAIN RESULTS: The primary end point was the proportion of responders (defined as a decrease in Acute Physiology and Chronic Health Evaluation II score by > or =4 points from study entry to day 4). Secondary outcomes were the Sequential Organ Failure Assessment score and its components, length of intensive care unit stay, survival rate, and safety of the adsorber treatment. Patient characteristics at entry were well balanced between the two treatment groups, except for a higher Sequential Organ Failure Assessment score in the adsorber group. On all-subjects-treated analysis, 65% of the adsorber group were responders vs. 57% for the standard (p =.389). A planned interim analysis restricted further enrollment to patients with peritonitis, in whom a slightly higher proportion of responders was observed with the adsorber treatment (69%) vs. standard treatment (54%, p =.159). There were no differences in survival, but adsorption treatment in peritonitis patients was associated with trends toward a reduction in length of intensive care unit stay and a more rapid decline in plasma endotoxin concentrations. There was a significantly greater reduction in platelet count with the adsorber; however, this did not require extra treatment. CONCLUSIONS: The endotoxin adsorber system did not result in a significantly improved primary end point in patients with presumed Gram-negative sepsis. In patients with peritonitis, the adsorber treatment likewise did not result in significantly improved Acute Physiology and Chronic Health Evaluation II scores. There were no clinically important side effects. These results provide encouragement for further study of adsorber treatment in patients with high likelihood of Gram-negative sepsis (e.g., peritonitis).


Subject(s)
Blood Component Removal/methods , Endotoxins/pharmacokinetics , Gram-Negative Bacterial Infections/therapy , Hemoperfusion/methods , Sepsis/therapy , APACHE , Adsorption , Female , Gram-Negative Bacterial Infections/blood , Hemoperfusion/adverse effects , Humans , Male , Middle Aged , Peritonitis/complications , Platelet Count , Sepsis/blood , Sepsis/etiology , Survival Analysis , Treatment Outcome
7.
Expert Rev Cardiovasc Ther ; 2(2): 239-51, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15151472

ABSTRACT

Less invasive approaches to cardiac surgical procedures are being developed in an effort to decrease patient morbidity and enhance postoperative recovery in comparison with conventional methods. Although full median sternotomy has been the standard surgical approach to the heart for more than 30 years, minimally invasive techniques using limited incisions are rapidly gaining acceptance. Potential advantages of a small skin incision include less trauma and tissue injury, leading to a less painful and quicker overall recovery, as well as shorter hospital stays for patients. Decreasing the size of the skin incision for minimally invasive valve surgery to significantly less than the cardiac size requires specific access to the valve to be repaired or replaced. Thus, various minimally invasive techniques and approaches have been described for aortic and mitral valve surgery. This article will review the different minimally invasive techniques and approaches, as well as early results and outcomes for aortic and mitral valve surgery.


Subject(s)
Cardiac Surgical Procedures/methods , Heart Valve Diseases/surgery , Heart Valves/surgery , Vascular Surgical Procedures/methods , Animals , Humans , Minimally Invasive Surgical Procedures
8.
Ann Thorac Surg ; 76(4): 1305-7, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14530040

ABSTRACT

We report the case of a 31-year-old woman with a 4-year history of recurrent palpitations, presenting with an increased frequency of paroxysms caused by ventricular tachycardias during pregnancy. A cardiac tumor of unknown origin infiltrating the right ventricle was diagnosed. Three weeks after prophylactic abrasion the tumor was totally excised with the use of cardiopulmonary bypass including restoration of the right ventricular wall and the tricuspid valve. Histology confirmed diagnosis of a benign cardiac lipoma. The postoperative course was uneventful and the patient was discharged 7 days after surgery. There was no episode of ventricular tachycardias during the 6-month follow-up.


Subject(s)
Heart Neoplasms/surgery , Heart Ventricles , Lipoma/surgery , Adult , Cardiopulmonary Bypass , Female , Humans
9.
Semin Thorac Cardiovasc Surg ; 15(2): 112-20, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12838481

ABSTRACT

Our goal of minimally invasive coronary bypass surgery is a completely endoscopic operation and anastomosis. Minimally invasive procedures reduce the invasiveness of the operation and therefore the morbidity and length of hospitalization of the patients. A possible solution to the technical problems that accompany manually performed endoscopic anastomoses is telemanipulation, which provides surgeons with the necessary equipment to accomplish totally endoscopic coronary anastomoses. Robotic telemetric systems together with 3-D visualization provide the necessary platform. This article summarizes the current worldwide experience with the ZEUS(TM) system in cardiac surgery and describes the steps from preclinical to endoscopic operation, focusing on the potential limitations of the procedure and the system.


Subject(s)
Coronary Artery Bypass/instrumentation , Robotics/instrumentation , Anastomosis, Surgical/instrumentation , Anastomosis, Surgical/methods , Animals , Coronary Artery Bypass/methods , Endoscopy , Equipment Design , Humans
10.
Heart Surg Forum ; 6(2): 77-83, 2003.
Article in English | MEDLINE | ID: mdl-12716586

ABSTRACT

BACKGROUND: We present our early and midterm results with off-pump coronary artery bypass grafting (OPCAB) on the beating heart and with conventional coronary artery bypass grafting (CABG) and compare patient outcomes for both procedures. METHODS: Between November 1997 and April 2001, OPCAB was performed in 330 patients. The results were compared with those of a matched population of 330 patients who had undergone CABG during the same period. Specific postoperative outcomes were evaluated for patient subgroups with multimorbidity, with impaired ventricular function, of an older age, and of a young age without comorbidities. Midterm results and quality-of-life (QOL) scores for patients were obtained by follow-up. RESULTS: In the overall series, OPCAB resulted in signifi- cantly shorter surgery times (P =.008), ventilation times (P <.001), intensive care unit (ICU) stays (P <.001), and hospital stays (P =.006). OPCAB also resulted in less postoperative inotropic medication (P =.041), lower transfusion rates (P <.001), fewer postoperative myocardial infarctions (P =.038), and lower hospital mortality rates (P =.024). Among the patient subgroups, patients with multimorbidities were the only subgroup to show a significant reduction in hospital mortality after OPCAB surgery (P =.048). Times of postoperative ventilation, ICU stay, and hospitalization were significantly reduced for all patient subgroups (P <.05). After mean followup times of 43.8 months (OPCAB) and 44.8 months (CABG), QOL scores, midterm complication rates, and mortality rates were not significantly different among the groups. CONCLUSION: OPCAB surgery improved postoperative recovery for the entire patient population without compromising midterm outcome. Compared with conventional CABG, high-risk patients with multimorbidity particularly profit from avoiding cardiopulmonary bypass and show significantly lower hospital mortality.


Subject(s)
Cardiopulmonary Bypass/methods , Coronary Artery Bypass/methods , Quality of Life , Aged , Aged, 80 and over , Cardiopulmonary Bypass/adverse effects , Case-Control Studies , Coronary Disease , Female , Follow-Up Studies , Hospital Mortality , Humans , Length of Stay , Male , Middle Aged , Myocardial Contraction , Myocardial Infarction , Myocardial Revascularization , Postoperative Complications , Time Factors , Treatment Outcome
11.
Surg Clin North Am ; 83(6): 1369-80, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14712872

ABSTRACT

The above described clinical series show that after a careful and thorough training program and stepwise introduction of surgical telemanipulation systems, application of telemanipulations is safe and shows acceptable results. Still, OR times are longer than for conventional procedures, and the operation is demanding, and expensive. The main shortcoming is that the procedure is only suitable for a highly selected patient population. However, despite all the clinical experience gathered in various centers, this technique is still evolving and in its beginning. There are some very promising developments that will improve the benefit of telemanipulators. For the first time, the separation of the surgeon from the surgical field facilitates training of surgeons on simulators. This might lead to a higher standard of surgical performance. Progress in sensor technology will make tactile-force feedback available, and new 3 D-visualization systems are designed to provide a better depth perception and higher resolution of the endoscopic image. Virtual stabilizing systems will enable robotic systems to operate on a virtual arrested heart without the need for CPB or mechanical stabilizers. These and other research topics summarized under the term augmented reality will enhance the natural senses and abilities of the surgeon. More and more, automatization will find its way into the OR. Preoperatively collected data about the patient's anatomy will be used to create safety margins, the robotic system will allow for the surgeon's movements, and instruments will be able to find their way to the surgical site without remote control. Because a stepwise approach has led to the clinical results that we and others have now achieved, it is the basis for further step-by-step development of the application of telemanipulation systems in coronary artery bypass grafting, and possibly other endoscopic procedures in cardiac surgery.


Subject(s)
Cardiac Surgical Procedures/methods , Robotics , Animals , Endoscopy/methods , Robotics/methods
12.
Ann Thorac Surg ; 74(2): 497-501, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12173835

ABSTRACT

BACKGROUND: This study was designed to evaluate the efficacy of two different stabilizer concepts for off-pump coronary artery bypass grafting. METHODS: Between 2000 and 2001, 100 consecutive patients who underwent off-pump coronary artery bypass grafting were randomly assigned to two stabilization systems: the Medtronic Octopus 3 (n = 50) and the Genzyme Immobilizer (n = 50). During operation, two-dimensional cardiac surface motion was assessed by intravital microscopy using orthogonal polarization spectral imaging in 20 vessels at the anterior wall. Postoperative angiography of 47 vessels revealed anastomotic quality. RESULTS: Patient demographics were similar in both groups regarding age, sex, ejection fraction, and New York Heart Association functional class. In 7 patients the randomized Immobilizer was rejected by the surgeon for lateral or posterior wall revascularization and subsequently switched to the Octopus device. Patients received 1.8 +/- 0.7 grafts in the Octopus and 1.6 +/- 0.5 in the Immobilizer group (p = not significant). Two-dimensional cardiac surface motion was significantly less using the Immobilizer (109.7 +/- 32.4 microm versus 423.5 +/- 129.6 microm; p < 0.001). Time required for anastomosis was significantly shorter in the Immobilizer group (11.3 +/- 3.5 versus 14.9 +/- 2.4 minutes; p < 0.001). Postoperative angiography showed no vessel occlusions but two anastomotic stenoses in each group. CONCLUSIONS: Both stabilizers have been shown useful for off-pump coronary artery bypass grafting. The Immobilizer system showed better epicardial immobilization of the anterior wall resulting in shorter anastomosis times. However, because the Octopus 3 handling is more flexible and allows easier access to all vessels, it is the device of choice for posterior wall revascularization in our institution.


Subject(s)
Coronary Artery Bypass/methods , Aged , Coronary Artery Bypass/instrumentation , Female , Humans , Male , Middle Aged , Prospective Studies
13.
Circulation ; 106(8): 1000-6, 2002 Aug 20.
Article in English | MEDLINE | ID: mdl-12186807

ABSTRACT

BACKGROUND: Ventricle-to-coronary artery bypass (VCAB) is an experimental revascularization procedure that provides predominantly systolic instead of diastolic blood flow to a coronary artery. METHODS AND RESULTS: In a pig model, a stent-based procedure (VSTENT) was developed to create a VCAB. After thoracotomy, a covered VSTENT was implanted between the left ventricle and the left anterior descending coronary artery (LAD). Distal LAD flow, regional myocardial function, and intracoronary pressures were determined at different degrees of LAD stenosis and during complete LAD occlusion. During 3 hours of LAD occlusion, VSTENT preserved net forward flow at 70+/-6% and regional myocardial function at 71+/-8% of baseline. Preservation of net flow was influenced by the positioning of the VSTENT, with higher preservation also under conditions of increased oxygen demand if a "valve-like mechanism" was present during diastole. At a hemodynamically relevant level of LAD stenosis (>70%), systolic inflow was predominant after VSTENT implantation. Changes in mean diastolic intracoronary pressure that resulted from different degrees of LAD stenosis were linearly correlated to net flow after VSTENT implantation (r=0.88; P<0.001). CONCLUSIONS: VSTENT for ventricle-to-coronary artery bypass was feasible and preserved 70+/-6% of baseline flow during complete LAD occlusion. The degree of preservation was dependent on the position of the VSTENT creating a valve-like mechanism during diastole. Residual diastolic blood flow through a high-grade LAD stenosis influenced net flow favorably, because diastolic backflow decreased with increasing mean diastolic intracoronary pressure.


Subject(s)
Coronary Artery Bypass/methods , Coronary Stenosis/surgery , Heart Ventricles/surgery , Stents , Animals , Coronary Angiography , Coronary Circulation , Coronary Stenosis/pathology , Coronary Stenosis/physiopathology , Coronary Vessels/pathology , Coronary Vessels/physiopathology , Feasibility Studies , Hemodynamics , Regional Blood Flow , Swine
14.
Heart Surg Forum ; 5(2): 128-31, 2002.
Article in English | MEDLINE | ID: mdl-12114126

ABSTRACT

BACKGROUND: There is concern that the technical limitations of robotic systems used in endoscopic coronary artery bypass grafting (CABG) may lead to increased trauma of the anastomotic site. To examine this issue, we compared the acute traumatic changes of the coronary artery wall caused by conventional manual suturing and robotically assisted suturing for anastomoses using the ZEUS telemanipulator (Computer Motion Inc., Goleta, CA) in a laboratory setting. METHODS: Coronary artery bypass grafting was performed on isolated porcine hearts. Fifteen anastomoses (with harvested porcine right coronary artery (RCA) segments) were carried out using the ZEUS microsurgical telemanipulator (group Z), while 15 further anastomoses were performed with a conventional manual technique (group M) using Gore-Tex CV-8 suture material. Specimens were taken from each anastomotic site and from native parts of the left anterior descending artery (LAD) (control group). Morphological changes of the cellular and fibrous components of the lamina intima and lamina media, and the shape and maximum diameter of the puncture mark, were examined by light microscopy (LM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Vascular endothelial damage and denudation were graded on a score from 1 to 5. RESULTS: In each group, 14 specimens were evaluated. SEM findings showed a significantly higher degree of endothelial denudation in group Z and group M compared to the control group, while group Z was significantly more affected than group M. Likewise, the maximum diameter of the puncture mark was significantly larger in group Z than in group M. TEM and LM studies supported these results. In addition, LM revealed that in five specimens of group Z the shape of the stitch through the artery wall was not cylindrical, as in the other cases, but was asymmetrical and displayed a superficial furrow on the side of the vascular lumen. CONCLUSION: The results indicate that there is an increased incidence of damage to the coronary artery wall caused by the microsurgical telemanipulator. Further studies are necessary to determine whether the differences between conventional and robotic-assisted suturing techniques will have an effect on the long-term outcome of coronary artery bypass grafting.


Subject(s)
Coronary Artery Bypass/adverse effects , Coronary Vessels/injuries , Endoscopy/methods , Robotics/methods , Anastomosis, Surgical , Animals , Coronary Artery Bypass/methods , Microscopy, Electron , Statistics, Nonparametric , Suture Techniques/adverse effects , Swine
15.
Heart Surg Forum ; 5(2): 157-62, 2002.
Article in English | MEDLINE | ID: mdl-12114131

ABSTRACT

OBJECTIVE: Coronary bypass surgery can be performed less invasively by avoiding cardiopulmonary bypass (CPB). We present our experiences with beating heart bypass surgery performed through a minithoracotomy or sternotomy. METHODS: From May 1997 to September 1999, 340 patients were included in a prospective study. Of these patients, 111 (group 1) underwent minimally invasive direct coronary artery bypass grafting (MIDCAB) through an antero-lateral minithoracotomy, and 229 (group 2) had off-pump coronary artery bypass grafting (OPCAB) through a full sternotomy. A pressure stabilizer was used for MIDCAB and a suction stabilizer for OPCAB surgery. Early postoperative angiography was performed on 48% of patients in group 1 and 45% of those in group 2. Statistical analysis was applied to compare the variables from both groups and a probability value of less than 0.05 was considered significant. RESULTS: In all MIDCAB grafts, revascularization was performed by a single left internal mammary artery (LIMA) graft to the left anterior descending coronary artery (LAD). This procedure was completed in 96.4% of patients without CPB. Conversion to sternotomy was necessary for one patient (0.9%). In the OPCAB group, an average of 1.7 grafts per patient were revascularized, of which 98 were single, 99 double, and 32 triple. Of the OPCAB group, 12% of patients were redo operations and 17% had severe comorbidities. Conversion to CPB was necessary for 10 patients (4.4%) because of hemodynamic instability. No cerebrovascular accident (CVA) was seen in any group. There were no hospital deaths in the MIDCAB group, but there were three deaths (1.3%) in the OPCAB group. Age, previous bypass surgery, and severe comorbidities did not influence early mortality. Early postoperative reoperation due to graft failure was necessary for three patients (2.7%) after MIDCAB and for three patients (1.3%) after OPCAB. Confirmed by angiography, the early postoperative total graft patency rate was 96.2% in the MIDCAB group and 96.6% in the OPCAB group; the perfect patency rate (no stenosis greater than 50%) was 92.4% and 93.1%, respectively. CONCLUSIONS: Coronary bypass surgery without the use of CPB is feasible and safe, and offers good early results. Nevertheless, MIDCAB grafting is a challenging technique and should only be performed in selected patients with favorable coronary anatomy. On the other hand, with the sternotomy approach, exposure of all vessels was well tolerated and made complete revascularization feasible. OPCAB can be performed safely even on high-risk patients.


Subject(s)
Coronary Artery Bypass/methods , Minimally Invasive Surgical Procedures , Cardiopulmonary Bypass , Chi-Square Distribution , Coronary Angiography , Female , Humans , Male , Middle Aged , Postoperative Complications , Prospective Studies , Statistics, Nonparametric , Sternum/surgery , Thoracotomy , Treatment Outcome
16.
Med Sci Monit ; 8(7): MT118-23, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12118209

ABSTRACT

BACKGROUND: Recently, the ZEUS(tm) Robotic Surgical System has been introduced to increase the precision of endoscopic cardiac surgery. This study investigated its clinical use for endoscopic coronary artery bypass grafting. MATERIAL/METHODS: Between 1998 and 2001, 41 patients with single and multivessel disease were operated on using the ZEUS(tm) system. The robotic system was introduced step by step into clinical practice. Initially, the system was used only for endoscopic internal mammary artery (IMA) harvest (n=12), later for coronary anastomoses on the arrested (n=13) or beating heart after median sternotomy (n=6), and finally for endoscopic coronary bypass grafting on either the arrested (n=2) or beating heart (n=8). RESULTS: Endoscopic IMA harvest ranged from 48 to 110 min and was completed in all cases. In the sternotomy group, the robotic anastomosis time averaged 21 min on the arrested and 25 min on the beating heart, respectively (n.s.). In the endoscopic cases, the average time for endoscopic anastomosis was 41 min on the arrested and 36.5 min on the beating heart (n.s.), with an overall duration of surgery between 4.0 and 8.0 hours. One endoscopic case was intraoperatively converted to a MIDCAB procedure with manual anastomosis. The total patency rate of all graft anastomoses, confirmed by early postoperative angiographic control, was 97%. One patient underwent reoperation with an uneventful postoperative course. CONCLUSIONS: The present study demonstrates the feasibility of endoscopic coronary revascularization using a computer-assisted surgical robotic system on the arrested and beating heart in selected patients.


Subject(s)
Cardiopulmonary Bypass , Coronary Artery Bypass/methods , Robotics , Surgery, Computer-Assisted , Adult , Aged , Angioscopy , Coronary Artery Bypass/instrumentation , Female , Humans , Male , Middle Aged , Myocardial Revascularization/methods , Robotics/instrumentation , Robotics/methods
17.
J Heart Lung Transplant ; 21(6): 680-6, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12057702

ABSTRACT

BACKGROUND: In patients with dilated cardiomyopathy (DCM), the heart enlarges, leading to a corresponding increase in ventricular wall stress. To reduce the stress, transventricular tension members (Myosplint, Myocor, Inc.) were implanted to change the left ventricle (LV) effective radius and to reduce the LV wall stress by 20%. We conducted this study to evaluate the intra- and peri-operative safety and feasibility of LV-shape change therapy. METHODS: In 7 patients, all diagnosed with DCM, Myosplints were implanted. New York Heart Association class ranged from III-IV, and LV end-diastolic diameter ranged from 70 to 102 mm. Mitral valve regurgitation was classified as mild in 3 and moderate in 4 cases. Four patients underwent mitral valve annuloplasty. RESULTS: We observed no significant device-related complications, such as thromboembolism, bleeding, device instability, or vascular damage, at 90 days. Early indications in a small patient population demonstrate some improvements in clinical parameters. CONCLUSIONS: From this initial experience, one may conclude that placement of the Myosplint devices can be safely performed without early, significant adverse events. In patients with significant mitral valve incompetence, concomitant mitral valve repair is indicated to realize the full benefit of the procedure. This study also suggests that Myosplints can be safely implanted in combination with mitral valve repair. The long-term effect of each procedure on cardiac function and survival will require further evaluation.


Subject(s)
Heart-Assist Devices , Prosthesis Implantation/instrumentation , Adult , Cardiomyopathy, Dilated/therapy , Female , Humans , Male , Middle Aged , Prosthesis Design , Severity of Illness Index
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