-
[show abstract]
[hide abstract]
ABSTRACT: The purpose of this study was to determine the possibility of a new surgical technique for the treatment of ventricular septal rupture after acute myocardial infarction. The operations were conducted under the guidance of real-time three-dimensional echocardiography (RT3DE) (iE33, Philips Medical Systems, Andover, MA). Six pigs were anesthetized, and after median sternotomy, the echo probe was applied directly to the surface of the heart. A ventricular septal defect (VSD) was created in all the six porcine hearts. The VSDs were closed with an Amplatzer septal occluder (AGA Medical Corp, Golden Valley, MN) through the right ventricular free wall under RT3DE monitoring. The procedure was successful in all the six pigs. The VSDs were precisely closed with the septal occluder under RT3DE guidance. Both left ventriculography and color-Doppler echocardiography showed no residual shunt in any of the six pigs. The use of the Amplatzer septal occluder under the guidance of real-time three-dimensional echocardiography made it possible to close the ventricular septal defect safely and successfully without the need to resort to cardiopulmonary bypass. Our results strongly suggest that the application of this new technique is feasible for the treatment of ventricular septal rupture after acute myocardial infarction.
Interactive cardiovascular and thoracic surgery 04/2009; 8(6):602-5.
-
Bob Kiaii,
R Scott McClure,
Peter Stewart,
Reiza Rayman,
Stuart A Swinamer, Yoshihiro Suematsu,
Stephanie Fox,
Jennifer Higgins,
Caroline Albion,
William J Kostuk, [......],
Patrick Teefy,
George Jablonsky,
Pantelis Diamantouros,
Wojciech B Dobkowski,
Philip Jones,
Daniel Bainbridge,
Ivan Iglesias,
John Murkin,
Davy Cheng,
Richard J Novick
[show abstract]
[hide abstract]
ABSTRACT: Traditionally integrated coronary artery revascularization has been described as a 2-stage procedure. We evaluated the safety and feasibility of 1-stage, simultaneous, hybrid, robotically assisted coronary artery bypass grafting surgery and percutaneous coronary intervention.
Fifty-eight patients underwent simultaneous, integrated coronary artery revascularization in an operating theater equipped with angiographic equipment. Forty-five patients were men. The mean age was 59 years. All internal thoracic arteries were harvested with robotic assistance. All anastomoses were manually constructed through a small anterior non-rib-spreading incision without cardiopulmonary bypass on the beating heart. Immediately after and within the same operative suite, both angiographic confirmation of graft patency and percutaneous coronary intervention were performed. In 52 patients therapeutic anticoagulation was achieved with the direct thrombin inhibitor bivalirudin.
There were no deaths or wound infections. There was 1 perioperative myocardial infarction. One patient had a stroke, and 3 patients required re-exploration for bleeding. The median lengths of intensive care and hospital stay were 1 and 4 days, respectively. All patients were alive and symptom free at follow-up (mean, 20.2 months; range, 1.1-40.8 months). Long-term angiographic follow-up in 54 patients showed 49 (91%) patent grafts (mean, 9.0 months; range, 4.3-40.8 months). There were 7 in-stent restenoses and 2 occluded stents.
For multivessel coronary artery disease, simultaneous integrated coronary artery revascularization with bivalirudin is safe and feasible. This approach enables complete multivessel revascularization with decreased surgical trauma and postoperative morbidity. Further studies are necessary to better determine patient selection and long-term outcomes.
The Journal of thoracic and cardiovascular surgery 10/2008; 136(3):702-8. · 3.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Real-time 3-dimensional (3D) ultrasound imaging has the potential to become a dominant imaging technique for minimally invasive surgery. One barrier to its widespread use is that surgical instruments generate imaging artifacts, which can obfuscate their location, orientation, and geometry and obscure nearby tissue. The purpose of this study was to identify and describe the types of artifacts which could be produced by metallic instruments during interventions guided by 3D ultrasound imaging.
Three imaging studies were performed. First, imaging artifacts from stainless steel rods were identified in vitro and acoustically characterized. Second, 3 typical minimally invasive instruments were imaged (in vitro and in vivo), and their artifacts were analyzed. The third study compared the intensity of imaging artifacts (in vitro and in vivo) from stainless steel rods with rods composed of 3 different materials and stainless steel rods with roughened and coated surfaces.
For the stainless steel rods, all observed artifacts are described and illustrated, and their physical origins are explained. Artifacts from the 3 minimally invasive instruments are characterized with the use of the artifacts observed with the rods. Finally, it is shown that artifacts can be greatly reduced through the use of alternate materials or by surface modification.
Instrument artifacts in 3D ultrasound images can be more confusing than those from the same instruments imaged in 2 dimensions. Real-time 3D ultrasound imaging can, however, be used effectively for in vivo imaging of minimally invasive instruments by using artifact mitigation techniques, including careful selection of probe and incision locations, as well as by instrument modification.
Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 11/2007; 26(10):1303-22. · 1.25 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Several advances in robotic technology and imaging systems have enabled the broad application of minimally invasive techniques in cardiac surgery. We have previously demonstrated that real-time three-dimensional echocardiography (RT3DE) provided adequate imaging and anatomic detail to act as a sole guide for surgical task performance. In this study, we examined the feasibility of robotic-assisted RT3DE-guided repair of atrial septal defect (ASD) in an in vitro study.
Exp. I: An RT3DE system with x4 matrix transducer (Sonos 7500, Philips Medical Systems, Andover, MA) was compared to two-dimensional echo (2DE) in the performance of common surgical tasks with the da Vinci Robotic Surgical System (Intuitive Surgical, Sunnyvale, CA). Completion times and deviation of suture from an echogenic target (mm) were measured. Exp. II: Porcine ASDs (n=10) were created and closed with robotic-assisted direct suturing in a water bath. During all experiments the operator was blinded to the target and operated only under ultrasonic guidance.
Compared to 2DE guidance, completion times improved by 70% (p<0.0001) and deviation of suture by the robotic system was significantly smaller (2DE: 4+/-2mm, 3DE: 0.2+/-0.3mm, p=0.0002) in RT3DE-guided tasks. RT3DE provided satisfactory images and sufficient anatomical detail for suturing. All surgical tasks were successfully performed with accuracy.
These initial experiments demonstrate the feasibility of robotic-assisted direct closure of ASD under RT3DE guidance. An endoscopic port access approach may be possible with refinements in telemanipulator technology and further development of the transesophageal echo transducer.
European Journal of Cardio-Thoracic Surgery 10/2007; 32(4):573-6. · 2.55 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We evaluated the feasibility and accuracy of live 3-dimensional (3D) epicardial echocardiography (echo) to guide the insertion of a retrograde cardioplegic catheter into the coronary sinus.
A real-time 3D echo system with a x4 matrix transducer was used. Live 3D echo-guided catheter insertion was compared with blind insertion. Completion times and success rates were recorded. During all experiments, the operator was blinded to the target and, in the echo-guided group, the procedure was performed with only ultrasonic guidance.
Live 3D echo provided sufficient spatial resolution and a satisfactory frame rate to provide a "virtual surgeon's view" of the relevant anatomy. Although there was no significant difference in completion time, live 3D echo guidance significantly improved the success rate of catheter insertion as compared to the blind group (90% versus 35%; P <.001).
Live 3D echo-guided coronary sinus catheter insertion is feasible and safe.
Heart Surgery Forum 02/2007; 10(3):E188-90. · 0.63 Impact Factor
-
Mitsuhiro Kawata,
Masaki Sekino,
Shinichi Takamoto,
Shoogo Ueno,
Sachiko Yamaguchi,
Kazuo Kitahori,
Hiroyuki Tsukihara, Yoshihiro Suematsu,
Minoru Ono,
Noboru Motomura,
Tetsuro Morota,
Arata Murakami
[show abstract]
[hide abstract]
ABSTRACT: Diffusion- and perfusion-weighted magnetic resonance imaging can identify ischemic brain injury in the hyperacute stage. For neuroprotection during thoracic aortic surgery, we developed a novel retrograde cerebral perfusion with intermittent pressure augmentation. The purpose of this study was to assess the efficiency of this novel method for neuroprotection in real time by using diffusion- and perfusion-weighted magnetic resonance imaging.
Sixteen beagle dogs were randomly divided into 4 groups: the antegrade selective cerebral perfusion group (n = 4; antegrade selective cerebral perfusion at a flow rate of 10 mL x kg(-1) x min(-1)); the intermittent retrograde cerebral perfusion group (n = 4; retrograde cerebral perfusion at a baseline pressure of 15 mm Hg with intermittent pressure augmentation to 45 mm Hg every 30 seconds); the conventional retrograde cerebral perfusion group (n = 4; conventional retrograde cerebral perfusion at a fixed pressure of 25 mm Hg); and the circulatory arrest group (n = 4; only circulatory arrest). Diffusion- and perfusion-weighted magnetic resonance images were acquired during each session of cerebral perfusion. Regions of interest were defined, and the apparent diffusion coefficient and relative regional cerebral blood volume were calculated in these regions of interest. Finally, the brain was evaluated for its histopathologic damage score.
The best apparent diffusion coefficient values were observed in the intermittent retrograde cerebral perfusion group in all the regions of interest, although the relative regional cerebral blood volume values were mostly lower than those in the antegrade selective cerebral perfusion group. The total Histopathologic Damage Score (0, normal; 32, worst) in the intermittent retrograde cerebral perfusion group (8.0 +/- 0.6) was significantly lower than that in the conventional retrograde cerebral perfusion (17.5 +/- 1.7; P < .01) and circulatory arrest (25 +/- 1.0; P < 0.01) groups and was equivalent to that in the antegrade selective cerebral perfusion group (7.8 +/- 0.8; P = .9).
Intermittent retrograde cerebral perfusion provides adequate neuroprotection by allowing high apparent diffusion coefficient values to be maintained.
The Journal of thoracic and cardiovascular surgery 11/2006; 132(4):933-40. · 3.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Current real-time three-dimensional echocardiography systems (RT3DE) can provide sufficient visualization to permit atrial septal defect (ASD) closure. However, detailed visualization of small objects inside the heart is still suboptimal because of limited resolution, which is a limitation for clinical application. We evaluate the complementary use of videocardioscopy in image-guided ASD closure.
In a pig model (n = 5), a 4-mm to 8-mm ASD was created with RT3DE guidance. Defect closure was accomplished with a catheter-based patch-delivery system fixed around the defect with mini-anchors under combined RT3DE and videocardioscopy guidance. The endoscope was inserted into the heart through a custom built port designed to allow visualization in the presence of blood.
All ASDs were successfully closed. The combination of RT3DE and videocardioscopy allowed detailed visualization of intracardiac structures, instruments, patch, and mini-anchors.
Beating-heart ASD closure can be achieved with combined RT3DE and videocardioscopy imaging. Use of videocardioscopy provides high-resolution imaging and likely improves safety of the image-guided procedure.
The Annals of thoracic surgery 11/2006; 82(4):1322-6; discussion 1326. · 3.74 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: For cerebral protection during aortic surgery, we introduced a novel retrograde cerebral perfusion method with intermittent pressure augmentation. We then assessed whether this novel method provides benefits similar to those provided by antegrade selective cerebral perfusion.
Eighteen dogs were randomly divided into 3 groups: the RCP-INT group, intermittent-retrograde cerebral perfusion at 15 mm Hg with intermittent pressure augmentation to 45 mm Hg (n = 6); the ASCP group, antegrade selective cerebral perfusion at a flow rate of 10 mL x kg(-1) x min(-1) (n = 6); and the sham group, no circulatory arrest (n = 6). Cooling (26 degrees C) with cardiopulmonary bypass and 60 minutes of circulatory arrest were performed in the RCP-INT and ASCP groups. The levels of tau protein in the cerebrospinal fluid and the diameters of the retinal vessels were measured. The neurologic deficit scores and the histopathologic damage scores of the brains were determined.
The total postoperative tau protein levels (calculated as the area under the curve) did not differ significantly between the RCP-INT and ASCP groups (203 +/- 87 pg x mL(-1) x h vs 154 +/- 69 pg x mL(-1) x h, P = .95). The retinal vessels were effectively dilated at an augmented pressure of 45 mm Hg in the RCP-INT group. The total neurologic deficit score (0 = normal, 500 = brain death) and histopathologic damage score (0 = normal, 40 = worst) were not significantly different between the RCP-INT and ASCP groups (neurologic deficit score: 75 +/- 21 vs 70 +/- 21, P = .98; histopathologic damage score: 13.5 +/- 1.5 vs 14.2 +/- 1.3, P = .84).
Intermittent augmented pressure dilated the cerebral vessels, allowing adequate blood supply without injuring the brain. This retrograde cerebral perfusion method provides adequate neuroprotection during moderate hypothermia.
The Journal of thoracic and cardiovascular surgery 08/2006; 132(1):80-8. · 3.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Current data suggest that erythropoietin protects the brain and the spinal cord from ischemic and traumatic injury. In this study, we determined whether erythropoietin protects the central nervous system during prolonged hypothermic circulatory arrest in an experimental canine model.
Ten adult beagle dogs were randomly and intravenously injected with either 5000 U/kg recombinant human erythropoietin or normal saline. Each dog was then subjected to a cardiopulmonary bypass and 120 minutes of deep hypothermic circulatory arrest (18 degrees C). The level of tau proteins in the cerebrospinal fluid, a modified marker of neurologic deficit in dogs, and the histopathologic characteristics of the brains and spinal cords were then examined.
The level of tau proteins was significantly lower in the erythropoietin-treated group than in the untreated group at 6 hours (20 +/- 12 vs 144 +/- 54 pg/mL; P = .036) and 12 hours (64 +/- 35 vs 478 +/- 103 pg/mL; P = .01) after the operation. The total Neurologic Deficit Score was 59 +/- 31 (0, normal; 500, brain death) in the erythropoietin-treated group, compared with 376 +/- 30 in the untreated group (P = .0117). Histopathologic examination revealed that ischemic neuronal changes and apoptosis in the hippocampus CA1 were significantly lower in the erythropoietin-treated group (P < .01 and P = .028, respectively).
This study showed that erythropoietin protected the central nervous system during prolonged hypothermic circulatory arrest, partly by preventing both necrosis (ischemic neuronal changes) and apoptosis.
The Journal of thoracic and cardiovascular surgery 06/2006; 131(6):1331-7. · 3.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Postoperative pericardial adhesions make a repeat sternotomy time-consuming and dangerous. The purpose of this study was to evaluate the efficacy of a new collagen pericardial substitute for preventing postoperative pericardial adhesions.
Our absorbable substitute consists of three layers: a middle layer of aterocollagen between two layers of sodium hyaluronic acid and aterocollagen. In experiment 1 in this study, the patch, made of 9,000 filaments of aterocollagen fibers, (group 1; n = 5) was compared with a patch made of 6,000 filaments (group 2; n = 7), an expanded polytetrafluoroethylene sheet (group 3; n = 6), and a control group (group 4; n = 4). Subsequently, in experiment 2, the patch was examined at 4 weeks (n = 5), 12 weeks (n = 5), and 24 weeks (n = 4) after the operation by light microscopy and scanning electron microscopy.
The area of adhesion in group 1 was significantly less as compared with that in the other three groups, and the coronary vessels were clearly identifiable; on the other hand, all the animals in the control group showed moderate to severe adhesions, and the coronary vessels were completely obscured. In experiment 2, formation of a membranous tissue resembling the native pericardial membrane was observed in all animals, and the thickness of this membrane showed a marked increase by 24 weeks after the operation. Light microscopy and scanning electron microscopy also showed the formation of a mesothelium-like lining.
The new absorbable and regenerative collagen patch seemed to be biocompatible, and its use was associated with minimal adhesion formation and preserved coronary anatomy.
The Annals of thoracic surgery 03/2006; 81(2):650-7. · 3.74 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This study reports on our initial experience with robotically assisted patent ductus arteriosus (PDA) closure and vascular ring division in children.
From April 2002 to May 2004, 15 patients underwent PDA closure (n = 9) and vascular ring repair (n = 6) by a totally endoscopic approach, utilizing the Da Vinci robotic system. The mean age of the patients was 8.3 +/- 4.7 years (range, 3 to 18) and the mean weight, 35.5 +/- 19.0 kg (range, 14.1 to 77.0 kg). Three thoracoscopic trocars were used to accommodate the endoscopic camera and two surgical instruments with an additional small incision for lung retraction. After dissection by the surgeon seated at the master console, PDA ligation with clips or division of the atretic arch and ductal ligament was performed.
Total operative times were 170 +/- 46 minutes (PDA) and 167 +/- 48 minutes (vascular ring). One patient with vascular ring was converted to thoracotomy because of dense adhesions due to previous surgery. Precise and easy surgical maneuver was possible with the articulated surgical instruments and three-dimensional visualization in 14 patients. Intraoperative transesophageal echocardiography confirmed no persistent shunt in all PDA patients. No laryngeal nerve injury and hemorrhage were noted. All patients were extubated in the operating room. Median length of postoperative hospital stay was 1.5 days.
Robotically assisted PDA closure and vascular ring division is a feasible and safe procedure. Future technologic improvement, including smaller instrument size and incorporation of tactile feedback, may permit application of this technique to even younger infants and intracardiac repairs.
The Annals of thoracic surgery 01/2006; 80(6):2309-13. · 3.74 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In this study, we tested 3 techniques of atrial septal defect closure under real-time 3-dimensional echocardiography guidance in a swine model.
The operations were conducted under the sole guidance of a modified real-time 3-dimensional echocardiography guidance system with a x4 matrix transducer (Sonos 7500, Philips Medical Systems, Andover, Mass). Eighteen swine were anesthetized, and after median sternotomy, the echo probe was applied directly to the surface of the right atrium. To create an atrial septal defect, balloon atrial septostomy and atrial septal defect enlargement were performed. Subsequently, 3 different techniques of atrial septal defect closure were attempted: group I, direct suture closure; group II, closure of the atrial septal defect using the Amplatzer device (AGA Medical Corp, Golden Valley, Minn); and group III, patch closure of the atrial septal defect (n = 6 each).
Real-time 3-dimensional echocardiography guidance provided sufficient spatial resolution and a satisfactory frame rate to provide a "virtual surgeon's view" of the relevant anatomy during the entire procedure. All atrial septal defects were enlarged, and the mean final size was 8.5 +/- 1.8 mm. Atrial septal defect closure was successfully accomplished with all the 3 surgical techniques examined. In groups I and III, the needles (1-3 sutures) and staples (6-12 staples) penetrated the tissue and patch material consistently, whereas in group III, the Amplatzer atrial septal defect device was easily deployed. There was no incident device/staple embolization or air introduction. Neither intraoperative 2-dimensional color Doppler echocardiography nor postmortem macro-evaluation revealed any residual shunts.
Beating heart atrial septal defect closure under real-time 3-dimensional echocardiographic guidance is feasible and, unlike catheter-based devices, applicable for any type of secundum atrial septal defect.
The Journal of thoracic and cardiovascular surgery 12/2005; 130(5):1348-57. · 3.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the impact of the guideline on the structural failure of current polyester vascular prostheses, we studied seven unsealed polyester vascular prostheses. An accelerated time test was used for assessing degradation of polymeric medical materials at pH 7.4 in phosphate buffer at a temperature of 95 degrees C. Probe burst strength was determined on the guideline and on standard parts of the prostheses during the accelerated time test. Weight-average molecular weights of the guideline and of the standard parts in all knitted grafts during the accelerated time test were measured. The guideline was significantly weaker than the standard parts in most prostheses. The guideline had significantly lower values of weight-average molecular weights than the standard parts in most knitted grafts. This study showed that guideline degeneration was one factor responsible for the structural failure of some current polyester vascular prostheses.
Artificial Organs 11/2005; 29(10):820-5. · 2.00 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We examined a novel protocol of retrograde cerebral perfusion with intermittent pressure augmentation to improve the clinical usefulness of this procedure, in a canine model, because a high retrograde cerebral perfusion pressure may be required to open cerebral vessels.
Eighteen dogs (25.2 +/- 4.1 kg) were randomly divided into the following 3 groups: circulatory arrest group (circulatory arrest alone), conventional-retrograde cerebral perfusion group (conventional retrograde cerebral perfusion at 25 mm Hg), and intermittent-retrograde cerebral perfusion group (retrograde cerebral perfusion at 15 mm Hg with intermittent pressure augmentation to 45 mm Hg). The animals were cooled down to 26 degrees C under cardiopulmonary bypass and underwent 60 minutes of circulatory arrest with or without retrograde cerebral perfusion in accordance with the protocol described. They were weaned from cardiopulmonary bypass after rewarming and observed for 12 hours after the procedures. The retinal vessels were observed as a means of noninvasive direct visualization of the cerebral vascular system. The level of Tau proteins in the cerebrospinal fluid was measured as a marker of neuronal damage.
While the retinal vessels were fully distended with blood (100%) at a retrograde cerebral perfusion pressure of 45 mm Hg in the intermittent-retrograde cerebral perfusion group, full distension of the retinal vessels was not observed in the conventional-retrograde cerebral perfusion group (67%). The level of Tau proteins, measured 12 hours after the operation, was lower in the intermittent-retrograde cerebral perfusion group (247 +/- 70 pg/mL) than in the circulatory arrest group (1313 +/- 463 pg/mL; P < .05) or the conventional-retrograde cerebral perfusion group (1449 +/- 693 pg/mL; P < .05). Histopathologic examination revealed that the most effective brain protection was obtained in the intermittent-retrograde cerebral perfusion group (P < .05).
Intermittent-retrograde cerebral perfusion effectively opens up cerebral vessels to allow adequate blood supply to the brain, thereby minimizing brain damage. This novel method may protect the cerebral system effectively from ischemia during circulatory arrest.
Journal of Thoracic and Cardiovascular Surgery 09/2005; 130(2):363-70. · 3.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The present study was designed to assess aortic valve morphology and function in mice of advanced age. We also evaluated the potential contribution of bone-marrow-derived cells to the pathogenesis of aortic stenosis.
Age-associated valvular degeneration is characterized by lipid accumulation, collagen deposition, and calcification containing smooth muscle-like cells and osteoblast-like cells. Cellular and molecular factors that mediate these changes remain unknown.
We extensively examined the aortic valves of senile wild-type and apolipoprotein E (ApoE)-/- mice with echocardiography. The aortic valves were analyzed by immunohistochemistry and electron microscopy. The bone marrow of wild-type and ApoE-/- mice was reconstituted with that of green fluorescent protein (GFP) or beta-galactosidase (LacZ) mice, which expressed GFP or LacZ ubiquitously.
Transaortic flow velocity was correlated with age in wild-type and ApoE-/- mice. The aortic valves of old ApoE-/- mice showed sclerosis that resembled the pathology of human aortic stenosis. A significant number of GFP-positive cells (10.7 +/- 4.1%) in the sclerotic valves of ApoE-/- mice expressed alpha-smooth muscle actin, whereas most of the GFP-positive cells were identified as endothelial cells or macrophages in wild-type mice. There were bone-marrow-derived cells that were positive for osteoblast-related proteins near the sites of ectopic calcification. The sclerotic valves displayed frequent apoptotic cell death and chemokine expression.
Senile ApoE-deficient mice display aortic valve sclerosis that is similar to that observed in humans. The sclerotic valves displayed frequent apoptotic cell death and chemokine expression. Smooth muscle-like cells observed in degenerative valves might derive, at least in part, from bone marrow.
Journal of the American College of Cardiology 08/2005; 46(1):134-41. · 14.16 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Human umbilical cord blood (UCB) contains an abundance of immature stem/progenitor cells and has been clinically used as an alternative to bone marrow transplantation. In addition, cord blood can be obtained non-invasively, in contrast to invasive bone marrow aspiration. We investigated the potential of human UCB CD34(+) cells to improve cardiac function following myocardial infarction. Myocardial infarction was induced in Wistar rats by ligation of the left coronary artery. Either 2x10(5) human UCB CD34(+) cells or equivalent cell-free medium was injected into the injured myocardium of the rats following induction of myocardial infarction. CD34(+) cell transplantation significantly improved ventricular function as compared to the control group. Immunofluorescence staining for human CD34, CD45, and PECAM-1 revealed surviving cells in the myocardium. Our findings suggest that transplanted human cells survived and improved cardiac function following myocardial infarction. These results may show the usefulness of UCB CD34(+) cells for myocardial infarction.
Biochemical and Biophysical Research Communications 03/2005; 327(2):609-14. · 2.48 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Advances in robotic technology and imaging systems have enabled the broad application of minimally invasive techniques in cardiac surgery, including coronary artery bypass grafting and mitral valve repair in adults. In pediatric cardiac surgery, however, current robotic systems have been used primarily to facilitate thoracoscopic pediatric procedures on extracardiac lesions, such as ligation of patent ductus and division of vascular rings. The use of smaller instruments with sophisticated robotic wrists may make it possible to perform more complex extracardiac procedures even in young infants. Additionally, future technological improvements, including incorporation of tactile feedback, instrument tracking, and intracardiac imaging (such as real-time 3-dimensional echocardiography), may enable intracardiac robotic surgery to be performed in children. This article reviews the current and potential future applications of pediatric robotic surgery and the developmental work required to enable performance of these procedures, along with an overview of the problems associated with the use of current robotic surgical systems in children.
The American Journal of Surgery 11/2004; 188(4A Suppl):98S-103S. · 2.78 Impact Factor
-
Yoshihiro Suematsu,
Gerald R Marx,
Jeffrey A Stoll,
Pierre E DuPont,
Robin O Cleveland,
Robert D Howe,
John K Triedman,
Tomislav Mihaljevic,
Bassem N Mora,
Bernie J Savord,
Ivan S Salgo,
Pedro J del Nido
[show abstract]
[hide abstract]
ABSTRACT: There is no current acceptable approach for intracardiac beating-heart interventions. We have adapted real-time 3-dimensional echocardiography with specialized instrumentation to facilitate beating-heart repair of atrial septal defects and mitral valve plasty to investigate the feasibility of real-time 3-dimensional echocardiography-guided cardiac surgery.
In experiment I a modified real-time 3-dimensional echocardiography system with x4 matrix transducer was compared with 2-dimensional echocardiography in the performance of common surgical tasks. Completion times, deviation from an ideal trajectory, and an echogenic target were measured. In experiment II porcine atrial septal defects were closed with an original semiautomatic suturing device (n = 4) and with a 5-mm endoscopic stapler and a pericardial or polytetrafluoroethylene patch (n = 4). In experiment III a pulsatile porcine mitral valve model was developed, and suture placement through the anterior and posterior mitral leaflets was performed (n = 8). During all experiments, the operator was blinded to the target and operated on only with ultrasonic guidance.
In experiment I, compared with 2-dimensional echocardiographic guidance, completion times improved by 21% ( P <.01) with high-trajectory accuracy, and suture deviation was significantly smaller (2-dimensional echocardiography, 5.4 +/- 2.7 mm; 3-dimensional echocardiography, 1.7 +/- 0.7 mm; P <.05) in real-time 3-dimensional echocardiography-guided tasks. In experiments II and III in both atrial septal defect closure and mitral valve plasty, real-time 3-dimensional echocardiography provided satisfactory images and sufficient anatomic detail for suturing and patch deployment. All surgical tasks were successfully performed with accuracy.
Real-time 3-dimensional echocardiography provides adequate imaging and anatomic detail to act as a sole guide for surgical task performance. These initial experiments demonstrate the feasibility of beating-heart direct or patch closure of atrial septal defects and mitral valve plasty without cardiopulmonary bypass.
Journal of Thoracic and Cardiovascular Surgery 10/2004; 128(4):579-87. · 3.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The efficacy of ischemic preconditioning of the heart has remained controversial. We investigated whether chronic treatment with beta-blockers affects the ischemic preconditioning in the isolated rat heart model.
Wistar rats were treated with propranolol (50 mg/kg/day, p.o.) (PRL), with nipradilol (10 mg/kg/day, p.o.) (NPL), or with vehicle, for 4 weeks. Isolated rat hearts were divided into global ischemia hearts (GI, PRL and NPL, each n=6) and ischemic preconditioned hearts (IP, PRL+IP and NPL+IP, each n=6).
Significant differences in left ventricular pressure were observed between the PRL and PRL+IP, and between the NPL and NPL+IP groups. In the NPL group, significant amelioration and preservation of left ventricular peak pressure, coronary flow, reduction of infarct size, and NOx preservation were observed. Lipid peroxidation in the NPL group was significantly reduced before and after global ischemia compared to the GI group.
The effect of ischemic preconditioning was abolished in the hearts of rats following oral treatment of propranolol or nipradilol. However, the administration of nipradilol protected the ischemic and reperfused myocardium, partly due to the prevention of lipid peroxide formation.
Scandinavian Cardiovascular Journal 10/2004; 38(5):293-9. · 0.93 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The surgical feasibility of beating-heart atrial septectomy under the guidance of two different types of real-time 3-dimensional echocardiography systems was examined.
A modified real-time 3-dimensional echocardiography system with a x4 matrix transducer (Sonos 7500; Philips Medical Systems, Andover, Mass) or a mechanical 1-dimensional array transducer (SSD-5500; Aloka Co, Ltd, Tokyo, Japan) was used. Small porcine atrial septal defects (n = 8) were enlarged with a Kerrison bone punch in the tank model. In the animal studies, small atrial septal defects (n = 8) were enlarged with the same device through a transatrial port. In both experiments, the area of the atrial septal defect measured by real-time 3-dimensional echocardiography was compared with the area measured directly.
Real-time 3-dimensional echocardiography provided satisfactory images and sufficient anatomic detail for the atrial septectomy in both experimental settings. All the atrial septal defects were successfully enlarged; an increase of as much as 293% of the preoperative atrial septal defect area was achieved in the tank experiment, and an increase of as great as 449% of the preoperative area was achieved in the animal experiment. The size of the atrial shunt was increased significantly after the atrial septectomy relative to that before the surgery (P <.0001). The percentage enlargement of the atrial septal defect measured by real-time 3-dimensional echocardiography was strongly correlated with that measured directly (both r(2) = 0.997, P <.0001) Bland-Altman analysis showed close agreement between the results obtained by the two measurement methods in both models.
Real-time 3-dimensional echocardiography provides satisfactory images and sufficient anatomic detail for atrial septectomy. This experiment demonstrates the surgical feasibility of a beating-heart intracardiac procedure such as atrial septectomy under real-time 3-dimensional echocardiographic guidance.
Journal of Thoracic and Cardiovascular Surgery 07/2004; 128(1):53-9. · 3.41 Impact Factor
