Biomedical subjects

Y Joseph Woo

Publications and source records attributed to Y Joseph Woo.

At least 19 recordsLinked to original sources

PubMed2006

Ischemic heart failure enhances endogenous myocardial apelin and APJ receptor expression.

Apelin interacts with the APJ receptor to enhance inotropy. In heart failure, apelin-APJ coupling may provide a means of enhancing myocardial function. The alterations in apelin and APJ receptor concentrations with ischemic cardiomyopathy are poorly understood. We investigated the compensatory changes in endogenous apelin and APJ levels in the setting of ischemic cardiomyopathy.Male, Lewis rats underwent LAD ligation and progressed into heart failure over 6 weeks. Corresponding animals underwent sham thoracotomy as control. Six weeks after initial surgery, the animals underwent hemodynamic functional analysis in the presence of exogenous apelin-13 infusion and the hearts were explanted for western blot and enzyme immunoassay analysis. Western blot analysis of myocardial APJ concentration demonstrated increased APJ receptor protein levels with heart failure (1890750+/-133500 vs. 901600+/-143120 intensity units, n=8, p=0.00001). Total apelin protein levels increased with ischemic heart failure as demonstrated by enzyme immunoassay (12.0+/-4.6 vs. 1.0+/-1.2 ng/ml, n=5, p=0.006) and western blot (1579400+/-477733 vs. 943000+/-157600 intensity units, n=10, p=0.008). Infusion of apelin-13 significantly enhanced myocardial function in sham and failing hearts. We conclude that total myocardial apelin and APJ receptor levels increase in compensation for ischemic cardiomyopathy.

Animals↗

PubMed2006

Therapeutic delivery of cyclin A2 induces myocardial regeneration and enhances cardiac function in ischemic heart failure.

BACKGROUND: Heart failure is a global health concern. As a novel therapeutic strategy, the induction of endogenous myocardial regeneration was investigated by initiating cardiomyocyte mitosis by expressing the cell cycle regulator cyclin A2. METHODS AND RESULTS: Lewis rats underwent left anterior descending coronary artery ligation followed by peri-infarct intramyocardial delivery of adenoviral vector expressing cyclin A2 (n =32) or empty adeno-null (n =32). Cyclin A2 expression was characterized by Western Blot and immunohistochemistry. Six weeks after surgery, in vivo myocardial function was analyzed using an ascending aortic flow probe and pressure-volume catheter. DNA synthesis was analyzed by proliferating cell nuclear antigen (PCNA), Ki-67, and BrdU. Mitosis was analyzed by phosphohistone-H3 expression. Myofilament density and ventricular geometry were assessed. Cyclin A2 levels peaked at 2 weeks and tapered off by 4 weeks. Borderzone cardiomyocyte cell cycle activation was demonstrated by increased PCNA (40.1+/-2.6 versus 9.3+/-1.1; P<0.0001), Ki-67 (46.3+/-7.2 versus 20.4+/-6.0; P<0.0001), BrdU (44.2+/-13.7 versus 5.2+/-5.2; P<0.05), and phosphohistone-H3 (12.7+/-1.4 versus 0+/-0; P<0.0001) positive cells/hpf. Cyclin A2 hearts demonstrated increased borderzone myofilament density (39.8+/-1.1 versus 31.8+/-1.0 cells/hpf; P=0.0011). Borderzone wall thickness was greater in cyclin A2 hearts (1.7+/-0.4 versus 1.4+/-0.04 mm; P<0.0001). Cyclin A2 animals manifested improved hemodynamics: Pmax (70.6+/-8.9 versus 60.4+/-11.8 mm Hg; P=0.017), max dP/dt (3000+/-588 versus 2500+/-643 mm Hg/sec; P<0.05), preload adjusted maximal power (5.75+/-4.40 versus 2.75+/-0.98 mWatts/microL2; P<0.05), and cardiac output (26.8+/-3.7 versus 22.7+/-2.6 mL/min; P=0.004). CONCLUSIONS: A therapeutic strategy of cyclin A2 expression via gene transfer induced cardiomyocyte cell cycle activation yielded increased borderzone myofilament density and improved myocardial function. This approach of inducing endogenous myocardial regeneration provides proof-of-concept evidence that cyclin A2 may ultimately serve as an efficient, alternative therapy for heart failure.

Actin Cytoskeleton↗

PubMed2006

Fructose 1,6-diphosphate administration attenuates post-ischemic ventricular dysfunction.

BACKGROUND: Cardiomyocyte energy production during ischemia depends upon anaerobic glycolysis inefficiently yielding two ATP per glucose. Substrate augmentation with fructose 1,6-diphosphate (FDP) bypasses the ATP consuming steps of glucokinase and phosphofructokinase thus yielding four ATP per FDP. This study evaluated the impact of FDP administration on myocardial function after acute ischemia. METHODS: Male Wistar rats, 250-300 g, underwent 30 min occlusion of the left anterior descending coronary artery followed by 30 min reperfusion. Immediately prior to both ischemia and reperfusion, animals received an intravenous bolus of FDP or saline control. After 30 min reperfusion, myocardial function was evaluated with a left ventricular intracavitary pressure/volume conductance microcatheter. For bioenergetics studies, myocardium was isolated at 5 min of ischemia and assayed for ATP levels. RESULTS: Compared to controls (n=8), FDP animals (n=8) demonstrated significantly improved maximal left ventricular pressure (100.5+/-5.4 mmHg versus 69.1+/-1.9 mmHg; p<0.0005), dP/dt (5296+/-531 mmHg/s versus 2940+/-175 mmHg/s; p<0.0028), ejection fraction (29.1+/-1.7% versus 20.4+/-1.4%; p<0.0017), and preload adjusted maximal power (59.3+/-5.0 mW/microL(2) versus 44.4+/-4.6 mW/microL(2); p<0.0477). Additionally, significantly enhanced ATP levels were observed in FDP animals (n=5) compared to controls (n=5) (535+/-156 nmol/g ischemic tissue versus 160+/-9.0 nmol/g ischemic tissue; p<0.0369). CONCLUSIONS: The administration of the glycolytic intermediate, FDP, by intravenous injection, resulted in significantly improved myocardial function after ischemia and improved bioenergetics during ischemia.

Adenosine Triphosphate↗

PubMed2006

Mesenchymal stem cell injection after myocardial infarction improves myocardial compliance.

Cellular therapy for myocardial injury has improved ventricular function in both animal and clinical studies, though the mechanism of benefit is unclear. This study was undertaken to examine the effects of cellular injection after infarction on myocardial elasticity. Coronary artery ligation of Lewis rats was followed by direct injection of human mesenchymal stem cells (MSCs) into the acutely ischemic myocardium. Two weeks postinfarct, myocardial elasticity was mapped by atomic force microscopy. MSC-injected hearts near the infarct region were twofold stiffer than myocardium from noninfarcted animals but softer than myocardium from vehicle-treated infarcted animals. After 8 wk, the following variables were evaluated: MSC engraftment and left ventricular geometry by histological methods, cardiac function with a pressure-volume conductance catheter, myocardial fibrosis by Masson Trichrome staining, vascularity by immunohistochemistry, and apoptosis by TdT-mediated dUTP nick-end labeling assay. The human cells engrafted and expressed a cardiomyocyte protein but stopped short of full differentiation and did not stimulate significant angiogenesis. MSC-injected hearts showed significantly less fibrosis than controls, as well as less left ventricular dilation, reduced apoptosis, increased myocardial thickness, and preservation of systolic and diastolic cardiac function. In summary, MSC injection after myocardial infarction did not regenerate contracting cardiomyocytes but reduced the stiffness of the subsequent scar and attenuated postinfarction remodeling, preserving some cardiac function. Improving scarred heart muscle compliance could be a functional benefit of cellular cardiomyoplasty.

Animals↗

PubMed2006

Safety and efficacy of left ventricular assist device support in postmyocardial infarction cardiogenic shock.

BACKGROUND: Cardiogenic shock secondary to acute myocardial infarction (CS-AMI) is the leading cause of death in all acute coronary syndromes. Experience with the use of left ventricular assist devices (LVADs) in patients with CS-AMI is limited. One of the surgical dilemmas when implanting an LVAD into a patient with an acute anterior wall myocardial infarction is the safety of apical cannulation. We present a decade of experience with the use of LVAD with apical cannulation in patients with CS-AMI. METHODS: A retrospective review of the ventricular assist device (VAD) database at the Hospital of the University of Pennsylvania was instituted. RESULTS: From April 1995 to February 2005, 49 patients received LVAD support for CS-AMI (group I). The majority of these patients suffered anterior wall myocardial infarctions. This group of patients was compared with a separate cohort of 61 patients with chronic ischemic cardiomyopathy who received LVAD support (group II). The VAD support successfully bridged 38 (74%) group I patients and 37 (61%) group II patients to heart transplantation. Of the 38 patients transplanted in group I, 33 (87%) were discharged from the hospital. In group II, 36 of the 37 patients transplanted (97%) survived to hospital discharge. The overall in-hospital mortality rates for the series were 33% for group I patients, and 41% for group II patients. CONCLUSIONS: Left ventricular assist device support in patients with CS-AMI is a safe and effective therapy which should be incorporated into the standard treatment paradigm for appropriate patients presenting with this lethal disease.

Female↗

PubMed2006

Neovasculogenic therapy to augment perfusion and preserve viability in ischemic cardiomyopathy.

BACKGROUND: Ischemic cardiomyopathy is a global health concern with limited therapy. We recently described endogenous revascularization utilizing granulocyte-macrophage colony stimulating factor (GMCSF) to induce endothelial progenitor cell (EPC) production and intramyocardial stromal cell-derived factor-1alpha (SDF) as a specific EPC chemokine. The EPC-mediated neovascularization and enhancement of myocardial function was observed. In this study we examined the regional biologic mechanisms underlying this therapy. METHODS: Lewis rats underwent left anterior descending coronary artery (LAD) ligation and developed ischemic cardiomyopathy over 6 weeks. Three weeks after ligation, the animals received either subcutaneous GMCSF and intramyocardial SDF injections or saline injections as control. Six weeks after LAD ligation circulating EPC density was studied by flow cytometry. Quadruple immunofluorescent vessel staining for mature, proliferating vasculature was performed. Confocal angiography was utilized to identify fluorescein lectin-lined vessels to assess perfusion. Ischemia reversal was studied by measuring myocardial adenosine triphosphate (ATP) levels. Myocardial viability was assayed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling detection of apoptosis and quantitation of myofilament density. RESULTS: The GMCSF/SDF therapy enhanced circulating leukocyte (13.1 +/- 4.5 x 10(6) vs 3.1 +/- 0.5 x 10(6)/cc, p = 0.001, n = 6) and EPC (14.2 +/- 6.6 vs 2.2 +/- 2.1/cc, p = 0.001, n = 6) concentrations. Tetraimmunofluorescent labeling demonstrated enhanced stable vasculature with this therapy (39.2 +/- 8.1 vs 25.4 +/- 5.1%, p = 0.006, n = 7). Enhanced perfusion was shown by confocal microangiography of borderzone lectin-labeled vessels (28.2 +/- 5.4 vs 11.5 +/- 3.0 vessels/high power field [hpf], p = 0.00001, n = 10). Ischemia reversal was demonstrated by enhanced cellular ATP levels in the GMCSF/SDF borderzone myocardium (102.5 +/- 31.0 vs 26.9 +/- 4.1 nmol/g, p = 0.008, n = 5). Borderzone cardiomyocyte viability was noted by decreased apoptosis (3.2 +/- 1.4% vs 5.4 +/- 1.0%, p = 0.004, n = 10) and enhanced cardiomyocyte density (40.0 +/- 5.6 vs 27.0 +/- 6 myofilaments/hpf, p = 0.01, n=10). CONCLUSIONS: Endogenous revascularization for ischemic cardiomyopathy utilizing GMCSF EPC upregulation and SDF EPC chemokinesis upregulates circulating EPCs, enhances vascular stability, and augments myocardial function by enhancing perfusion, reversing cellular ischemia, and increasing cardiomyocyte viability.

Animals↗

PubMed2006

Robotic minimally invasive mitral valve reconstruction yields less blood product transfusion and shorter length of stay.

BACKGROUND: Robotic-assisted minimally invasive mitral valve reconstruction has gained popularity recently. Initial reports suggest that this approach can be used with relative safety and efficacy. Direct comparisons with a traditional sternotomy approach have not yet been explored extensively. METHODS: All mitral valve procedures that were performed by a single surgeon during a 3-year period of time were analyzed (n = 142 procedures). Patients whose condition required concomitant coronary artery bypass grafting or aortic valve surgery were excluded subsequently from analysis, because all of these patients were approached obligatorily by sternotomy (n = 71 patients). Six patients underwent right thoracotomy mitral valve procedures without robotic assistance, and 1 patient in cardiogenic shock underwent emergent mitral valve reconstruction by sternotomy. Of the remaining 64 patients who were eligible theoretically for sternotomy or robotic-assisted minimally invasive surgery, 39 patients underwent sternotomy, and 25 patients underwent right chest minimally invasive robotic-assisted surgery. Randomization between these 2 approaches would be almost impossible in the United States. The primary determinant for the choice of approach was request of the referring physician or patient. Multiple perioperative outcomes were then compared. RESULTS: Patients who underwent sternotomy and robotic-assisted surgery exhibited equivalent preoperative characteristics and experienced an equivalent degree of correction of mitral regurgitation in repairs and in need for replacement. Complex mitral valve repairs that entailed leaflet resection and reapproximation, annular plication, sliding annuloplasty, chordal transfer, and GoreTex neochordal construction were accomplished successfully with the robotic system. Cross-clamp and bypass times were longer for patients in the minimally invasive group (110 vs 151 minutes; P = .0015; 162 vs 239 minutes; P < .001, respectively). Mean packed red blood cell transfusion was lower among patients who underwent robotic-assisted surgery (5.0 vs 2.8 units; P = .04). Patients who underwent robotic-assisted surgeries experienced shorter mean duration of postoperative hospitalization (10.6 vs 7.1 days; P = .04). There was 1 death among the patients who underwent sternotomy, and no deaths among the patients who underwent robotic-assisted surgery. CONCLUSION: Patients can undergo mitral valve reconstruction with minimally invasive robotic assistance, avoid a sternotomy, require less blood product transfusion, and experience shorter hospitalization.

Cardiopulmonary Bypass↗

PubMed2006

Minimally invasive, robotic, and off-pump mitral valve surgery.

A significant transformation is occurring in the management of mitral valve disease. Earlier surgery is now recommended. Mitral valve repair is the standard of care, and newer methods of reconstructing the mitral valve are developing. Surgery with videoscopic assistance can be effectively performed without sternotomy. Robotics systems are gaining wider adoption. Implantable devices to repair or replace the mitral valve off-pump and percutaneously are emerging.

Cardiopulmonary Bypass↗

PubMed2006

Off-pump revascularization for significant left ventricular dysfunction.

Left ventricular dysfunction is a predictor of perioperative morbidity and mortality in on-pump coronary artery bypass grafting. Obligatory global myocardial ischemia and injury induced during crossclamping as well as adverse systemic effects of cardiopulmonary bypass may induce a disproportionately greater overall physiologic insult in patients with poor ventricular function. All patients undergoing nonemergency off-pump coronary artery bypass by a single surgeon during an 18-month period were retrospectively analyzed. Two groups with preoperative ejection fraction classified as poor (10%-35%; n = 31) or normal (55%-80%; n = 60) were compared. The mean ejection fractions were 26% +/- 1% and 63% +/- 1% respectively, p < 0.000001. In those with significant left ventricular dysfunction, there were 2.8 +/- 0.1 grafts per patient, time to extubation was 8.4 +/- 1.2 hours, and discharge was after 4.9 +/- 0.6 days. These results were statistically equivalent to those in the group with normal left ventricular function. There was no intraaortic balloon pump insertion or mortality in either group. This technique provides an effective means of safely revascularizing patients with significant left ventricular dysfunction, and it may provide a valuable alternative approach in patients with ischemic cardiomyopathy.

Aged↗

PubMed2006

Left main coronary embolism.

This is a case of a 58-year-old female with a history of mitral regurgitation who had undergone mitral valve repair and was readmitted in cardiogenic shock with pericardial effusion, and then developed an anterior ST-elevation myocardial infarction. Coronary angiography revealed an embolus in the left main artery which was treated with rheolytic thrombectomy. This represents an uncommon cause of acute myocardial infarction.

Coronary Angiography↗

PubMed2005

One year transgene expression with adeno-associated virus cardiac gene transfer.

BACKGROUND: Adeno-associated virus (AAV) has shown promise as a vector for cardiac gene transfer given its ability to stably integrate into the host genome and its lack of immune reactivity. This study examined the feasibility of AAV-mediated myocardial gene transfer in mice, the animal which, because of transgenic technology, has become the disease model of choice for cardiovascular research. METHODS: AAV encoding the cytomegalovirus promoter driven LacZ reporter gene (10(7) LacZ-forming units per animal) or vehicle control was injected into the hearts of young adult C57Bl/6 mice by a transdiaphragmatic approach. At one, two, three, six, and twelve months post-injection, cardiac function was assessed by transthoracic echocardiography and hearts were assayed by X-gal histochemical staining. RESULTS: Echocardiography revealed normal left ventricular function in both AAV and control groups at all time points. X-gal staining of cryostat sections of hearts revealed uniform LacZ expression at all time points. There were minimal signs of immunologic infiltration by hematoxylin and eosin staining. CONCLUSIONS: AAV-mediated myocardial gene transfer by transdiaphragmatic injection can be conducted safely and results in long-term expression of the LacZ gene for at least one year without causing significant inflammatory response or adversely affecting LV systolic function.

Animals↗

PubMed2005

Robotic resection of an aortic valve papillary fibroelastoma.

Robotic technology has been applied to multiple cardiac surgical procedures. Purported benefits include decreased tissue trauma, reduced postoperative bleeding, fewer blood product transfusions, and shorter lengths of stay. We describe the case of a 50-year-old man with an incidentally discovered 1-cm mobile mass on the edge of the aortic valve noncoronary leaflet. The patient underwent robotic minimally invasive resection. The pathologic examination revealed papillary fibroelastoma.

Aortic Valve↗

PubMed2005

Neurological monitoring and off-pump surgery in a very high-risk stroke patient.

Stroke remains a high risk of coronary artery bypass grafting. We present a patient with progressively symptomatic coronary disease and severe four-vessel cerebrovascular disease not amenable to revascularization. This patient underwent coronary revascularization without neurologic complication using off-pump coronary surgery to avoid aortic manipulation and intraoperative electroencephalographic monitoring of cerebral perfusion. This management strategy may reduce the stroke risk in similar patients.

Coronary Artery Bypass, Off-Pump↗

PubMed2005

Intraoperative effects of the coapsys annuloplasty system in a randomized evaluation (RESTOR-MV) of functional ischemic mitral regurgitation.

BACKGROUND: Functional ischemic mitral regurgitation (MR) frequently arises after myocardial infarction; it is characterized by annular enlargement or lateral displacement of the subvalvular apparatus. Coapsys is a ventricular-annular remodeling device designed to treat functional ischemic MR; it does not require cardiopulmonary bypass. Initial intraoperative results of the RESTOR-MV randomized clinical trial are presented. METHODS: Patients referred for coronary artery bypass grafting with preoperative MR grade of 2 or greater were studied, excluding those with structural valve abnormalities. The Coapsys device, which consists of two epicardial pads connected by a flexible cord, was surgically implanted in 19 patients. Under epicardial echocardiographic guidance, the cord was passed through the left ventricle and tightened externally to improve leaflet coaptation and stabilize the ventricular wall; tightening was conducted with color flow Doppler imaging. RESULTS: Patients were 64.5 +/- 9.2 years old with an ejection fraction of 0.383 +/- 0.089 and received 2.7 +/- 1.1 grafts. Intraoperative MR grade was 2.7 +/- 0.8 after induction and was reduced to 0.4 +/- 0.7 after implantation (p < 0.0001). Mean epicardial dimension was reduced from 8.5 +/- 1.2 to 6.4 +/- 0.9 cm (p < 0.0001). Intraoperative MR was reduced in 95% (18 of 19) of patients, and 84% (16 of 19) had MR grade 1 or less after implantation. All implants were performed without cardiopulmonary bypass or conversion to standard annuloplasty. No hemodynamic compromise or structural damage to the mitral apparatus was noted. Significant acute remodeling was noted in the left ventricular dimensions. CONCLUSIONS: In patients without structural valve disease, the Coapsys device acutely reduces functional MR. Further randomized evaluation will assess long-term stability and compare it with standard annuloplasty techniques.

Aged↗

PubMed2005

Ethyl pyruvate enhances ATP levels, reduces oxidative stress and preserves cardiac function in a rat model of off-pump coronary bypass.

BACKGROUND: Off-pump coronary artery bypass grafting is associated with transient periods of myocardial ischemia during revascularization resulting in myocardial contractile dysfunction and oxidative injury. The purpose of this study was to investigate the efficacy of ethyl pyruvate as a myocardial protective agent in a rat model of off-pump coronary artery bypass grafting associated with transient myocardial dysfunction without infarction. METHODS: Wistar rats were subjected to transient ischemia via 10 min occlusion of the LAD coronary artery followed by 10 min of reperfusion. Animals received an IV bolus of Ringer's solution as a control (n=10) or Ringer's ethyl pyruvate (n=10) immediately before the initiation of ischemia and reperfusion. Myocardial ATP and lipid peroxidation levels were quantified for an estimation of energetics and oxidative stress, respectively. In vivo cardiac function was assessed throughout the ischemia and reperfusion periods. RESULTS: Ethyl pyruvate significantly increased myocardial ATP levels compared to controls (2650+/-759 nmol/g versus 892+/-276 nmol/g, p=0.04). Myocardial oxidative stress was significantly reduced in animals treated with ethyl pyruvate compared to controls (70.4+/-2.6 nmol/g versus 81.8+/-2.4 nmol/g, p=0.04). dP/dt max and cardiac output were significantly greater in the ethyl pyruvate group compared to controls during ischemia and reperfusion. CONCLUSIONS: Ethyl pyruvate enhances myocardial ATP levels, reduces oxidative stress, and preserves myocardial function in a model of transient ischemia/reperfusion injury not subject to myocardial infarction.

Adenosine Triphosphate↗

PubMed2005

Stromal cell-derived factor and granulocyte-monocyte colony-stimulating factor form a combined neovasculogenic therapy for ischemic cardiomyopathy.

OBJECTIVE: Ischemic heart failure is an increasingly prevalent global health concern with major morbidity and mortality. Currently, therapies are limited, and novel revascularization methods might have a role. This study examined enhancing endogenous myocardial revascularization by expanding bone marrow-derived endothelial progenitor cells with the marrow stimulant granulocyte-monocyte colony-stimulating factor and recruiting the endothelial progenitor cells with intramyocardial administration of the potent endothelial progenitor cell chemokine stromal cell-derived factor. METHODS: Ischemic cardiomyopathy was induced in Lewis rats (n = 40) through left anterior descending coronary artery ligation. After 3 weeks, animals were randomized into 4 groups: saline control, granulocyte-monocyte colony-stimulating factor only (GM-CSF only), stromal cell-derived factor only (SDF only), and combined stromal cell-derived factor/granulocyte-monocyte colony-stimulating factor (SDF/GM-CSF) (n = 10 each). After another 3 weeks, hearts were analyzed for endothelial progenitor cell density by endothelial progenitor cell marker colocalization immunohistochemistry, vasculogenesis by von Willebrand immunohistochemistry, ventricular geometry by hematoxylin-and-eosin microscopy, and in vivo myocardial function with an intracavitary pressure-volume conductance microcatheter. RESULTS: The saline control, GM-CSF only, and SDF only groups were equivalent. Compared with the saline control group, animals in the SDF/GM-CSF group exhibited increased endothelial progenitor cell density (21.7 +/- 3.2 vs 9.6 +/- 3.1 CD34 + /vascular endothelial growth factor receptor 2-positive cells per high-power field, P = .01). There was enhanced vascularity (44.1 +/- 5.5 versus 23.8 +/- 2.2 von Willebrand factor-positive vessels per high-power field, P = .007). SDF/GM-CSF group animals experienced less adverse ventricular remodeling, as manifested by less cavitary dilatation (9.8 +/- 0.1 mm vs 10.1 +/- 0.1 mm [control], P = .04) and increased border-zone wall thickness (1.78 +/- 0.19 vs 1.41 +/- 0.16 mm [control], P = .03). (SDF/GM-CSF group animals had improved cardiac function compared with animals in the saline control group (maximum pressure: 93.9 +/- 3.2 vs 71.7 +/- 3.1 mm Hg, P < .001; maximum dP/dt: 3513 +/- 303 vs 2602 +/- 201 mm Hg/s, P < .05; cardiac output: 21.3 +/- 2.7 vs 13.3 +/- 1.3 mL/min, P < .01; end-systolic pressure-volume relationship slope: 1.7 +/- 0.4 vs 0.5 +/- 0.2 mm Hg/microL, P < .01.) CONCLUSION: This novel revascularization strategy of bone marrow stimulation and intramyocardial delivery of the endothelial progenitor cell chemokine stromal cell-derived factor yielded significantly enhanced myocardial endothelial progenitor cell density, vasculogenesis, geometric preservation, and contractility in a model of ischemic cardiomyopathy.

Angiogenesis Inducing Agents↗

PubMed2005

Cardiac surgery in patients on antiplatelet and antithrombotic agents.

The widespread application of antithrombotic agents carries significant potential for inducing excessive peri-operative hemorrhage during cardiac surgery. Specific surgical and medical strategies can be employed to attenuate this bleeding. These antithrombotic agents and anti-hemorrhagic measures will be reviewed in depth.

Aged↗

PubMed2005

Robotic microlaryngeal surgery: a technical feasibility study using the daVinci surgical robot and an airway mannequin.

OBJECTIVES/HYPOTHESIS: The trend toward minimally invasive surgery has led to the development and mastery of endoscopic and laparoscopic surgical techniques. These minimally invasive approaches, which only two decades ago were either novel or experimental, are now mainstream. More recently, robot-assisted surgery has evolved as an adjunct to open and endoscopic techniques. Surgical robots are now approved by the United States Food and Drug Administration for a variety of thoracic and abdominal/pelvic surgical procedures. The purpose of this study is to demonstrate the technical feasibility of robot-assisted microlaryngeal surgery. STUDY DESIGN: Experimental surgical manipulation of the larynx in an airway mannequin with a surgical robot. METHODS: A variety of laryngoscopes and mouthgags, coupled with the daVinci Surgical Robot's (Intuitive Surgical, Sunnyvale, CA) 0-degree and 30-degree, two-dimensional and three-dimensional endoscopes, were utilized to optimize visualization of the larynx in an airway mannequin. Five millimeter and 8 mm microinstruments compatible with the daVinci robot were utilized to manipulate different elements of the larynx. Experiments were recorded with both still and video photography. RESULTS: The endoscope and robotic arms of the daVinci robot are well suited to airway surgery. CONCLUSIONS: Robot-assisted laryngeal surgery can be performed with currently available technology. The potential for fine manipulation of tissues, increased freedom of instrument movement, and endolaryngeal suturing may increase the precision of endoscopic laryngeal microsurgery and offers the potential to increase the variety of laryngeal procedures that can be performed endoscopically.

Feasibility Studies↗