Biomedical subjects

Christian Detter

Publications and source records attributed to Christian Detter.

17 recordsLinked to original sources

PubMed2006

Sirolimus and FK778: a comparison of two anti-proliferative immunosuppressants for prevention of experimental obliterative airway disease.

This study examined the efficacies of sirolimus and the novel immunosuppressive agent FK778 to prevent obliterative airway disease (OAD). Tracheae from Brown-Norway donors were heterotopically transplanted in the greater omentum of Lewis rats. Recipients were treated for 28 days with sirolimus (0.5 or 2 mg/kg), FK778 (5 or 20 mg/kg), or combination regimens (0.5 + 5 mg/kg, 2 + 20 mg/kg). Tracheal segments were evaluated for degree of luminal obliteration, percentage of luminal epithelial cell coverage, and peritracheal infiltration. In vitro smooth muscle cell (SMC) proliferation and migration assays were performed to assess direct nonimmune-related effects of the drugs. Sirolimus 2 mg/kg and FK778 20 mg/kg effectively reduced graft infiltration and prevented airway obliteration, whereas FK778 5 mg/kg was insufficient. Sirolimus 0.5 mg/kg at least showed moderate inhibitory effects on luminal obliteration and graft infiltration. Combination regimens revealed no significant beneficial effects. Both sirolimus and FK778 barely showed preserved epithelial coverage. Within the range of relevant concentrations, FK778 showed more potent anti-proliferative and anti-migratory effects on SMC in vitro than sirolimus. Both agents proved effective to prevent OAD development without preserving relevant amounts of epithelium. The anti-proliferative potency on SMCs seems to be an especially important mechanism for FK778. De novo combination regimens revealed no beneficial interaction and thus remain doubtful.

Alkynes↗

PubMed2005

The Cardica C-Port System: clinical and angiographic evaluation of a new device for automated, compliant distal anastomoses in coronary artery bypass grafting surgery--a multicenter prospective clinical trial.

OBJECTIVES: The C-Port System (Cardica, Inc, Redwood City, Calif) integrates in one tool all functions necessary to enable rapid automated distal coronary anastomoses. The goal of this prospective, nonrandomized, and multicenter study is to determine the safety and efficacy of this novel anastomotic system. METHODS: Five centers enrolled 133 patients awaiting elective coronary artery bypass grafting surgery. Outcome variables were intraoperative device performance, incidence of device-related adverse events, predischarge and 6-month angiographic graft patency, and 12-month clinical outcome. Independent core laboratories performed qualitative and quantitative angiographic and computed tomographic assessments. RESULTS: The C-Port was used to perform a vein-to-coronary anastomosis in 130 patients. Intraoperative conversion to a hand-sewn anastomosis was necessary in 11 patients because of inadequate target site preparation, inappropriate target vessel selection, or both. Inadequate blood flow related to poor runoff required conversion in 3 additional patients. Three patients died before discharge of causes unrelated to the device. At discharge, 113 patients had a C-Port implant in place, and 104 C-Port anastomoses were studied by means of angiography, resulting in 100 FitzGibbon A, 3 FitzGibbon B, and 1 FitzGibbon 0 classifications. At 6 months, one additional patient died of a device-unrelated cause, and 98 patients were evaluated by means of angiography (n = 89). Overall patency (FitzGibbon A) was 92.1%. Three C-Port anastomoses were rated FitzGibbon B, and 4 were rated FitzGibbon 0. At 12 months, 107 (98.2%) of 109 alive patients were followed up, without any reports of device-related major adverse cardiac events. CONCLUSIONS: The C-Port System allows for a rapid, reliable, and compliant distal anastomosis and yields favorable 6-month angiographic and 12-month clinical results when compared with published studies.

Aged↗

PubMed2005

FK778 and tacrolimus prevent the development of obliterative airway disease after heterotopic rat tracheal transplantation.

BACKGROUND: The effectiveness of the novel immunosuppressive agent FK778 and of tacrolimus to prevent the development of obliterative airway disease (OAD) was investigated in an animal model. METHODS: Tracheae from Brown-Norway donors were heterotopically transplanted in the greater omentum of Lewis rats. Recipients were treated for 28 days with FK778 (5 or 20 mg/kg), tacrolimus (1 or 4 mg/kg) or combination regimens at varying doses (5 + 1 mg/kg, 10 + 2 mg/kg or 20 + 4 mg/kg). Grafts were harvested and processed for histologic and immunohistochemical evaluation. Lymphocyte surface antigen expression was quantified and in vitro smooth muscle cell (SMC) proliferation assays were performed. RESULTS: In untreated recipients, very large amounts of infiltrating CD4+, CD8+ and ED1+ mononuclear cells were observed in the peritracheal region with epithelial loss and complete luminal obliteration. Granulation tissue consisted of alpha-actin-positive cells and collagen-rich fibrosis. FK778 and tacrolimus as well as combination regimens of both agents dose-dependently inhibited peritracheal infiltration and luminal obliteration. Only tacrolimus-treated recipients showed preserved luminal epithelial coverage with airway goblet cells, whereas, in animals that received FK778, no epithelium was found. Both agents equally suppressed in vivo lymphocyte CD25 expression. Only FK778-treated animals were completely free of adverse drug side effects. FK778 but not tacrolimus showed potent anti-proliferative effects on SMC in vitro. CONCLUSIONS: Although both agents proved effective to prevent OAD development, histology revealed major differences. The anti-proliferative potency of FK778 on SMC may be an important mechanism of action. Combination regimens showed favorable drug interaction and allowed dose reduction of both agents to achieve maximal immunosuppressive efficacy.

Actins↗

PubMed2005

Video and robotic-assisted minimally invasive mitral valve surgery: a comparison of the Port-Access and transthoracic clamp techniques.

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.

Cardiopulmonary Bypass↗

PubMed2004

Minimally invasive valve surgery: different techniques and approaches.

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.

Animals↗

PubMed2003

Successful resection of a symptomatic right ventricular lipoma.

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.

Adult↗

PubMed2003

Incorporating robotics into an open-heart program.

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.

Animals↗

PubMed2003

Sevoflurane provides greater protection of the myocardium than propofol in patients undergoing off-pump coronary artery bypass surgery.

BACKGROUND: Sevoflurane, like other halogenated anesthetics, has been shown to have a protective effect on the myocardium at risk after an ischemic injury. The current study tested the hypothesis that such beneficial effects, so far mainly seen in the laboratory, are reproducible in humans. METHODS: After institutional review board approval, 20 patients scheduled to undergo elective off-pump coronary artery bypass surgery were randomized to receive general anesthesia with either sevoflurane or propofol. Except for this, anesthetic and surgical management was the same in both groups. For assessing myocardial injury, troponin I and myocardial fraction of creatine kinase were determined during the first 24 postoperative hours. Systemic hemodynamic variables were measured before, during, and after completion of coronary artery bypass. RESULTS: Troponin I concentrations increased significantly more in propofol-anesthetized patients than in patients anesthetized with sevoflurane. CONCLUSION: Patients receiving sevoflurane for off-pump coronary artery surgery had less myocardial injury during the first 24 postoperative hours than patients receiving propofol. The results further support cardioprotective effects of sevoflurane.

Aged↗

PubMed2003

Early and midterm results after coronary artery bypass grafting with and without cardiopulmonary bypass: which patient population benefits the most?

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.

Aged↗

PubMed2003

Robotically assisted coronary artery bypass surgery with the ZEUS telemanipulator system.

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.

Anastomosis, Surgical↗

PubMed2002

Comparison of two stabilizer concepts for off-pump coronary artery bypass grafting.

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.

Aged↗

PubMed2002

Multidetector computed tomography (MDCT) in coronary surgery: first experiences with a new tool for diagnosis of coronary artery disease.

BACKGROUND: Selective coronary angiography (SCA) is the standard invasive procedure for diagnosis in patients eligible for coronary artery bypass grafting (CABG). A recently developed, highly sensitive multidetector computed tomography (MDCT) scan holds promise to be of almost comparable quality and predictiveness. We examined a blinded series of preoperative patients who were admitted to hospital for conventional and minimally invasive CABG procedures. Patients underwent CT scans in addition to SCA; findings were compared regarding location and degree of coronary artery stenosis. METHODS: Twenty patients underwent electrocardiogram-gated helical CT scanning. Images with 250 ms effective exposure time were reconstructed with retrospective electrocardiogram gating. Location and degree of coronary stenoses were described and compared with findings of SCA. The study was limited to patients with a heart rate of less than 70 beats per minute and who had the ability to hold their breath for 20 to 30 seconds. RESULTS: Coronary arteries were clearly displayed by MDCT. Compared with SCA, sensitivity was 92%, specificity 84%, and negative predicted value 89% for significant stenosis (more than 50%). Early forms of atherosclerotic changes were even clearer on MDCT. In addition, the CT examination allowed differentiation of calcified and fatty or fibrous stenoses. CONCLUSIONS: Multidetector CT scanning is an effective noninvasive technique for the diagnosis of coronary artery disease. In selected patients, MDCT scanning might be able to replace SCA as a preoperative test for CABG procedures. The intrathoracic situs can be clearly exposed as it is important for the planning of minimally invasive CABG procedures.

Coronary Angiography↗

PubMed2002

Myosplint implant and shape-change procedure: intra- and peri-operative safety and feasibility.

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.

Adult↗

PubMed2002

Evaluation of acute traumatic changes of the coronary artery wall after robotically assisted endoscopic coronary artery bypass grafting.

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.

Anastomosis, Surgical↗

PubMed2002

Minimally invasive direct coronary artery bypass grafting (MIDCAB) and off-pump coronary artery bypass grafting (OPCAB): two techniques for beating heart surgery.

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.

Cardiopulmonary Bypass↗

PubMed2002

Robotically-assisted coronary artery surgery with and without cardiopulmonary bypass - from first clinical use to endoscopic operation.

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.

Adult↗

PubMed2002

Near-infrared fluorescence coronary angiography: a new noninvasive technology for intraoperative graft patency control.

BACKGROUND: Intraoperative graft patency verification is of major clinical importance for quality control after coronary artery bypass grafting (CABG), especially if surgery is performed on the beating heart. This is one of the first reports of fluorescence coronary angiography (FCA) using the dye indocyanine green (ICG), a noninvasive technology for direct visualization of coronary arteries, bypass grafts, and myocardial perfusion. METHODS: Twenty-three domestic pigs (weight, 45-72 kg) underwent FCA of the left anterior descending coronary artery (LAD). In the first group (n = 6 pigs), FCA was used to visualize the native coronary vessels and myocardial perfusion. In the second group (n = 8 pigs), 14 stenoses of various degrees and 4 total vessel occlusions were created by snares on different segments of the LAD, and FCA was used to visualize the effects of these obstructions. In the third group (n = 9 pigs), a coronary bypass procedure on the beating heart was performed by a left internal mammary artery or a human saphenous vein graft to the LAD, and FCA was used to visualize graft patency. Three pigs were removed from the study because of ventricular fibrillation. ICG was intravenously applied, and the heart was illuminated with near-infrared light emitted by laser diodes. The fluorescence emission was detected by an adapted charge-coupled device camera system. The images were displayed in real time on a high-resolution monitor. Subsequently, images obtained with FCA were compared to those obtained with coronary angiography (n = 10 pigs). RESULTS: In all cases, high-quality FCA images of coronary arteries and myocardial perfusion were obtained. All stenoses resulted in an impairment of the myocardial perfusion visualized by FCA. Occlusion of the LAD or the diagonal branch resulted in a total perfusion defect of the corresponding anterior myocardial wall with immediate reperfusion after releasing the snare. In 5 cases a patent bypass graft with an apparent homogenous perfusion of the corresponding myocardium was detectable. In one procedure, FCA images indicated total occlusion of the bypass graft and a total perfusion deficit in the distal LAD region. Correlation between FCA and coronary angiography in detection of stenoses and graft patency was excellent. CONCLUSION: With the fluorescence technique using ICG, visualization of blood flow in coronary vessels and bypass grafts, as well as of myocardial perfusion, is feasible. FCA is a highly sensitive and reproducible method and an excellent technique for intraoperative quality control in CABG.

Animals↗