... Praėjus metams po operacijos, 86 proc. ligonių prieirdių vir-pėjimo neufiksuota. Tokius po... more ... Praėjus metams po operacijos, 86 proc. ligonių prieirdių vir-pėjimo neufiksuota. Tokius pooperacinio ritmo kitimo dėsningumus nurodo ir kiti tyrinėtojai. M. Pasic su ... First experience.) Medicina (Kaunas) 2001;37:1136-8. 17. Pasic M, Bergs P, Müller P, et al. ...
The Journal of Thoracic and Cardiovascular Surgery, 1990
March 1990 radiography, with special emphasis on the cardiothoracic ratio (normally 0.49); (2) M-... more March 1990 radiography, with special emphasis on the cardiothoracic ratio (normally 0.49); (2) M-mode echocardiography; (3) computed tomography of the chest; (4) transthoracic pericardiocentesis and fluid analysis with Sudan III staining and triglyceride analysis; (5) lymphangiography, with a goal to demonstrate a commun ication between lymphatic channels and the thoracic structures; and (6) oral administration triolein labeled with iodine 131 followed by (a) analysis of the pericardial fluid versus blood for radioactivity and (b) external cardiac imaging. The management of the aberrant chylous effusion often necessitates pericardiocentesis (which is both diagnostic and curative), pericardiectomy, thoracostomy drainage, and ligation or resection of the thoracic duct in the lower part of the chest. Dietary support dictates medium/small chain fatty acid/low fat meals.'
The Journal of Heart and Lung Transplantation, 2008
Background: The application of axial-flow pumps in patients with end-stage heart failure reveals ... more Background: The application of axial-flow pumps in patients with end-stage heart failure reveals a significantly reduced infectious complication rate as compared with rates observed with pulsatile devices. The remaining adverse event rate relates mainly to thromboembolic complications with neurologic consequences. We investigated the dependence of the neurologic adverse event rate on the length of the inflow cannula. Methods: A total of 216 consecutive patients with an axial-flow pump (INCOR; Berlin Heart GmbH, Berlin, Germany) were included in a retrospective multi-center analysis. In 138 patients, a short inflow cannula (24-mm tip length into the left ventricle), and in 78 patients a long inflow cannula (tip length 34 mm) was applied. Results: Patients with a long inflow cannula (LC) demonstrated a better survival rate than those with a short inflow cannula (SC) at the end of the observation period (LC, 63.4%; SC, 52.9%; p ϭ 0.05). The thromboembolic adverse event rate was also significantly lower. Only 3 of the 78 patients (3.8%) with an LC had a thromboembolic adverse event (thromboembolic events per patient-year ϭ 0.11) as compared with 32 (23.2%) of SC patients (thromboembolic events per patient-year ϭ 0.50, p Ͻ 0.001). Conclusions: Patients with a long inflow cannula had a better survival rate and a lower incidence of cerebrovascular adverse events than patients with a short inflow cannula.
It seems that mitral valve (MV) replacement technique is already standardized but still under dis... more It seems that mitral valve (MV) replacement technique is already standardized but still under discussion is the surgical approach. At Heart Surgery Clinic of Vilnius University MV replacement was started in 1970 (our total experience in valve surgery is 4396 operations). The most popular surgical approach was through left atrium (LA) from the right side. In cases with small atrium we used right atrial and transseptal and transverse transeptal biatrial (TTBA) approach. Left atrium approach is quite useful in many cases except those with small LA, LV hypertrophy and heart rotation when it can result a greater trauma for the heart, extended time of operation and, possibly, reduced performance after it. From September 1992 till May 1993 we used extended vertical transseptal (EVT) approach in 18 patients for MV replacement or repair, mitral and aortic valve replacement was performed for 5 patients, mitral valve replacement and tricuspid valvuloplasty for 13 patients, 5 patients had mitra...
It seems that mitral valve (MV) replacement technique is already standardized but still under dis... more It seems that mitral valve (MV) replacement technique is already standardized but still under discussion is the surgical approach. At Heart Surgery Clinic of Vilnius University MV replacement was started in 1970 (our total experience in valve surgery is 4396 operations). The most popular surgical approach was through left atrium (LA) from the right side. In cases with small atrium we used right atrial and transseptal and transverse transeptal biatrial (TTBA) approach. Left atrium approach is quite useful in many cases except those with small LA, LV hypertrophy and heart rotation when it can result a greater trauma for the heart, extended time of operation and, possibly, reduced performance after it. From September 1992 till May 1993 we used extended vertical transseptal (EVT) approach in 18 patients for MV replacement or repair, mitral and aortic valve replacement was performed for 5 patients, mitral valve replacement and tricuspid valvuloplasty for 13 patients, 5 patients had mitra...
We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimen... more We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimensional structuring for applications in tissue engineering. The direct laser writing system enables fabrication of artificial polymeric scaffolds over a large area (up to cm in lateral size) with sub-micrometer resolution which could find practical applications in biomedicine and surgery. Yb:KGW femtosecond laser oscillator (Pharos, Light Conversion. Co. Ltd.) is used as an irradiation source (75 fs, 515 nm (frequency doubled), 80 MHz). The sample is mounted on wide range linear motor driven stages having 10 nm sample positioning resolution (XY-ALS130-100, Z-ALS130-50, Aerotech, Inc.). These stages guarantee an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support the linear scanning speed up to 300 mm/s. By moving the sample three-dimensionally the position of laser focus in the photopolymer is changed and one is able to write complex 3D (three-dimensional) structures. An illumination system and CMOS camera enables online process monitoring. Control of all equipment is automated via custom made computer software ``3D-Poli'' specially designed for LTPP applications. Structures can be imported from computer aided design STereoLihography (stl) files or programmed directly. It can be used for rapid LTPP structuring in various photopolymers (SZ2080, AKRE19, PEG-DA-258) which are known to be suitable for bio-applications. Microstructured scaffolds can be produced on different substrates like glass, plastic and metal. In this paper, we present microfabricated polymeric scaffolds over a large area and growing of adult rabbit myogenic stem cells on them. Obtained results show the polymeric scaffolds to be applicable for cell growth practice. It exhibit potential to use it for artificial pericardium in the experimental model in the future.
Interactive CardioVascular and Thoracic Surgery, 2008
The purpose of this study was to evaluate sensitisation, occurring because of bridging with VAD, ... more The purpose of this study was to evaluate sensitisation, occurring because of bridging with VAD, and development of rejection episodes after transplantation in selected groups of patients using triple drug immunosuppression, without induction or desensitisation therapy. Sensitisation using standard complement dependent cytotoxicity was tested in 16 patients awaiting cardiac transplantation before VAD placement, one month post-implantation and on a six-monthly basis later on. Long-term (955"998 days) post-transplant course of six transplanted post-VAD patients was compared with 19 non-bridged recipients (follow-up time 1425"1273 days) of the same age. One-third of VAD recipients had developed anti-HLA antibodies one month post-implantation; 4y16 patients were sensitised six months after implantation. No de novo sensitisation development was revealed in VAD group post-transplantation. All sensitised patients independent of VAD placement underwent graft rejection episodes. Only 1 of 6 VAD recipient was treated because of grade 2R rejection, compared to 6y19 in the non-bridged group, Ps0.63. None of the patients had failed because of early graft rejection. In conclusion, VAD devices used in our centre cause low level risk for anti-HLA antibodies development. There were no differences in survival due to immunologic reasons between VAD bridged and non-bridged patients.
Interactive CardioVascular and Thoracic Surgery, 2006
Objective: The crucial decision to progress from pharmacological treatment of acute decompensated... more Objective: The crucial decision to progress from pharmacological treatment of acute decompensated heart failure to institution of assist device or transplantation begins with evaluation of the chances for a successful recovery. We tested whether the intra-aortic balloon counterpulsation (IABP) could give us the necessary time for clinical decision-making and preserve adequate circulation until it is made. Methods: We assessed 11 dilated cardiomyopathy patients of NYHA class IV, listed for heart transplantation or a ventricular assist device (VAD), who had conventional IABP placed. Heart function prior to and after IABP insertion as well as hemodynamics, end-organ function (renal and hepatic), frequency of complications and clinical outcomes were assessed. Results: The duration of intra-aortic balloon pump insertion ranged from 72 to 360 h (mean 181.54"81.65). After 48 h of intra-aortic balloon pump support, there was a significant increase of mean systemic arterial pressure from 74.5"9.6 to 82.3"4.7 mmHg (Ps0.02), and ejection fraction from 14.7"6.4 to 21.0"8.6 (Ps0.014). Meanwhile improvement of cardiac index, pulmonary wedge pressure and end-organ perfusion markers did not reach statistical significance. Three patients were successfully weaned off the balloon and recovered without additional interventions, two patients were transplanted and three were supported with counterpulsation until the implantation of assist device. Three patients died due to progressive heart failure, two after IABP removal and one after VAD implantation. There was no incidence of infection, limb ischemia, thrombus, or embolic complications. Conclusions: Our data showed that intra-aortic balloon pump support may be successfully and safely used in the acute decompensated dilated cardiomyopathy patients, as an urgent measure of cardiac support, to stabilize the patient and maintain organ perfusion until transplant is available, VAD is placed or patient is weaned from IABP.
Background: The Ross procedure has resolved the major problem in the management of aortic valve d... more Background: The Ross procedure has resolved the major problem in the management of aortic valve disease in the young, The operation can be performed in childhood and procedes an ideal valve substitute, which does not require anticoagulation, has growth potential and is free from degeneration. Methods: Short-and mid-term results of 45 patients after Ross procedure (December 1993 through April 1999) were reviewed. The aim of this study was to evaluate postoperative haemodynamic performance of this procedure, to asses the impact of modifications on postoperative results, and to make inferences that may improve results. Results. There were four early deaths (9%), no late deaths and no reoperations. Thirty-four patients had no or trivial symptoms, six patients had mild symptoms and one patient, moderate regurgitation of neo-aortic valve at the last echocardiographic study. Stenosis was not present at rest or during exercise. An obvious regression of left ventricle hypertrophy was detected (248 Ϯ 94-10 Ϯ 34 g/m). Reinforcement of the proximal suture line of the pulmonary autograft with pericardial strips does not restrict the growth of the aortic annulus. Dilatation of the aortic root was detected in all patients. The mean gradient through pulmonary homograft was 11.5 mmHg. Conclusions: The Ross procedure provides optimal haemodynamic function from the neoaortic valve, leading to regression of left ventricular hypertrophy and near normal life style, without anticoagulation. Dilatation of the neo-aortic root diameter postoperatively was not associated with progressing of regurgitation. Concern still exists over future valve function, particularly in patients with a diagnosis of bicuspid dilated incompetent aortic valves.
SummaryAtrial fibrillation (AF) is a common complication of coronary artery bypass grafting (CABG... more SummaryAtrial fibrillation (AF) is a common complication of coronary artery bypass grafting (CABG). We sought to determine the diagnostic validity of plasma biomarkers of i) inflammation (marked by interleukin-6 [IL-6] and high-sensitivity C-reactive protein [hs-CRP]), ii) extracellular matrix remodelling (matrix metalloproteinase [MMP-9], tissue inhibitor of matrix metalloproteinase [TIMP-1]) and iii) the prothrombotic state (tissue factor and von Willebrand factor [vWF]) in the risk prediction of post-operative AF. Samples were obtained preoperatively from peripheral/femoral vein and from intracardiac chambers (right atrium [RA], the right atrial appendage [RAA], the left atrium [LA] and the left atrial appendage [LAA]) amongst 100 consecutive patients free of AF and inflammatory disease undergoing elective CABG. Biomarker concentrations were related to incident AF (30 days). At 30 days post CABG, 30 patients were proven to have had AF. Concentrations of tissue factor (TF) and vWF...
Background: Atrial fibrillation (AF) is a common complication of coronary artery bypass grafting ... more Background: Atrial fibrillation (AF) is a common complication of coronary artery bypass grafting (CABG), and may have an inflammatory and/or thrombotic etiology. We sought to determine the expression of inflammatory (interleukin [IL]-6), thrombotic (tissue factor and von Willebrand factor [VWF]) and remodeling (matrix metalloproteinase [MMP]-9 and tissue inhibitor of metalloproteinase [TIMP]-1) markers by left atrial appendage (LAA) and right atrial appendage (RAA) tissue in the prediction of postoperative AF. We determined whether the tissue expression of markers of certain different pathophysiologic mechanisms predicted the development of AF after CABG. Methods: LAA and RAA tissue was excised during CABG in 100 patients free of AF and inflammation. Tissue marker expression was quantified by immunohistochemistry and was related to 30-day postoperative AF. Results: Overall, there were no significant differences in staining intensity of any marker between LAA tissue and RAA tissue. However, more intense expression of VWF by LAA tissue predicted the 30 patients with postoperative AF as compared with those free of AF (P = 0.006). IL-6, MMP-9 and TIMP-1 expression by RAA and LAA epicardial tissue was stronger than expression by endocardium or cardiomyocytes (all P < 0.025) but failed to predict AF. Conclusion: In this study, one of the largest to investigate tissue expression of pathophysiologic markers in relation to postoperative AF, we show that more intense expression of VWF by LAA tissue is a significant predictor of postoperative AF. This points towards a possible role of endothelial damage/dysfunction (as reflected by VWF changes) in the pathogenesis of postoperative AF.
The Journal of Heart and Lung Transplantation, 2008
Purpose: Right ventricular (RV) failure after left ventricular assist device (LVAD) placement is ... more Purpose: Right ventricular (RV) failure after left ventricular assist device (LVAD) placement is a serious complication with a poor prognosis and is difficult to predict. In the era of LVAD use as destination therapy and alternatives such as the total artificial heart, predicting post-LVAD RV failure requiring mechanical support is extremely important. Methods and Materials: We reviewed patient characteristics, laboratory values, and hemodynamic data from 266 patients who underwent LVAD placement at the University of Pennsylvania from April 1995 to June 2007. Results: Of 266 LVAD patients, 99 required RV assist device (BiVAD) placement (37%). We compared 36 parameters between LVAD (nϭ167) and BiVAD patients (nϭ99) to determine preoperative risk factors for RV assist device (RVAD) need. By univariate analysis, 23 variables showed statistically significant differences between the two groups (P Յ 0.05). The strongest of these were female gender, low body surface area, echocardiographic evidence of severe preoperative RV dysfunction, previous cardiac surgery, preoperative mechanical ventilation, elevated creatinine, elevated INR, elevated central venous pressure, low systolic blood pressure (SBP), low pulmonary artery systolic and mean pressures, low cardiac index (CI), low mixed venous oxygen saturation, and low right ventricular stroke work index (RVSWI). By multivariate logistic regression, CI Ͻ 2.3 L/min⅐m 2 (odds ratio [OR] 5.7), RVSWI Յ 0.25 mmHg⅐mL/m 2 (OR 5.1), severe preoperative RV dysfunction (OR 5.0), preoperative creatinine Ն 1.9 mg/dL (OR 4.8), previous cardiac surgery (OR 4.5), and SBP Յ 96 mmHg (OR 2.9) were the best predictors of RVAD need. Conclusions: The most significant predictors for RVAD need were CI, RVSWI, severe preoperative RV dysfunction, creatinine, previous cardiac surgery, and SBP. Using these factors, we have constructed an algorithm which can predict which LVAD patients will require RVAD with greater than 80% sensitivity and specificity.
The study assesses the impact of a program using a model of knowledge transfer on the long-term d... more The study assesses the impact of a program using a model of knowledge transfer on the long-term development of a pediatric cardiac service in Lithuania. A team from the United Kingdom evaluated Lithuanian pediatric cardiac services and provided support in areas targeted for improvement. The total number of infant operations performed in Lithuania from 1990 to 2008, together with in-hospital mortality rates, was broken down into 3 time periods and analyzed to estimate the efficacy of the program: (1) 1990-1998, before the program; (2) 1999-2002, during the program; (3) 2003-2008, following the end of the program. Lithuanian results in children older than 1 year were comparable with other European centers. However, only 315 infant and neonatal cardiac procedures were performed between 1990 and 1998, and there was an in-hospital mortality of 34.2%. Between 1999 and 2002, the UK team performed 23 highly complex demonstration procedures (in-hospital mortality, 13%). During the same period the Lithuanian team performed 305 additional operations in neonates and infants, and in-hospital mortality decreased to 18.7%. From 2003 to 2008 results continued to improve-559 infant operations were performed, with in-hospital mortality of 11.3% (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .0001). Knowledge transfer has led to substantial and sustainable long-term improvement in the results of infant cardiac surgery in Lithuania. Demonstrating techniques and care on a limited number of more complex cases is an efficient way of transferring knowledge and skills to the developing pediatric cardiac centers.
We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimen... more We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimensional structuring for applications in tissue engineering. The direct laser writing system enables fabrication of artificial polymeric scaffolds over a large area (up to cm in lateral size) with sub-micrometer resolution which could find practical applications in biomedicine and surgery. Yb:KGW femtosecond laser oscillator (Pharos, Light Conversion. Co. Ltd.) is used as an irradiation source (75 fs, 515 nm (frequency doubled), 80 MHz). The sample is mounted on wide range linear motor driven stages having 10 nm sample positioning resolution (XY-ALS130-100, Z-ALS130-50, Aerotech, Inc.). These stages guarantee an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support the linear scanning speed up to 300 mm/s. By moving the sample three-dimensionally the position of laser focus in the photopolymer is changed and one is able to write complex 3D (three-dimensional) structures. An illumination system and CMOS camera enables online process monitoring. Control of all equipment is automated via custom made computer software ``3D-Poli'' specially designed for LTPP applications. Structures can be imported from computer aided design STereoLihography (stl) files or programmed directly. It can be used for rapid LTPP structuring in various photopolymers (SZ2080, AKRE19, PEG-DA-258) which are known to be suitable for bio-applications. Microstructured scaffolds can be produced on different substrates like glass, plastic and metal. In this paper, we present microfabricated polymeric scaffolds over a large area and growing of adult rabbit myogenic stem cells on them. Obtained results show the polymeric scaffolds to be applicable for cell growth practice. It exhibit potential to use it for artificial pericardium in the experimental model in the future.
Biophotonics: Photonic Solutions For Better Health Care Ii, 2010
A tightly focused ultrafast pulsed laser beam is guided into the volume of the photosensitive mat... more A tightly focused ultrafast pulsed laser beam is guided into the volume of the photosensitive material and induces nonlinear photomodification. By translating the sample, the position of the focus is changed relatively, thus point-by-point complex 3D structures can be written inside the bulk. In this report, we present a Laser Two-Photon Polymerization (LTPP) setup for three-dimensional micro/nanostructuring for applications in photonics, microoptics, micromechanics, microfluidics and biomedicine. This system enables fabrication of functional devices over a large area (up to several cm in lateral size) with reproducible sub-micrometer resolution (up to 200 nm). In our experiments a Yb:KGW active media laser oscillator (75 fs, 200 kW, 515 nm frequency doubled, 80 MHz) was used as an irradiation source. The sample was mounted on XYZ wide range linear motor driven positioning stages having 10 nm positioning resolution. These stages enable an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support a linear scanning speed of up to 300 mm/s. Control of all the equipment was automated via custom made computer software "3D-Poli" specially designed for LTPP applications. The model of the structure can be imported as CAD file, this enables rapid and flexible structuring out of various photopolymers like ORMOCERs, ORMOSILs, acrylates and PEG-DAs which are commonly used in conventional UV mask, nanoimprint and µ-stereolithographies. In this paper, we demonstrate polymeric microstructures fabricated over a large area on glass, plastic and metal substrates. This opens a way to produce functional devices like photonic crystals, microlenses, micromechanic and microfluidic components and artificial scaffolds as templates for cell growth. Additionally, results of primary myogenic stem cells expanding on microfabricated polymeric scaffolds are provided. Cell proliferation tests show the material and structure to be biocompatible for the biomedical practice. Downloaded from SPIE Digital Library on 25 May 2010 to 78.61.217.42. Terms of Use: http://spiedl.org/terms Proc. of SPIE Vol. 7715 77151F-2 Downloaded from SPIE Digital Library on 25 May 2010 to 78.61.217.42. Terms of Use: http://spiedl.org/terms
In this work, we applied a constructed multi-photon polymerization system based on diode-pumped s... more In this work, we applied a constructed multi-photon polymerization system based on diode-pumped solid state femtosecond Yb:KGW laser used as pulsed irradiation light source (300 fs, 1030 nm, 200 kHz) in combination with large area high sample translation velocity (up to 300 mm/s) linear motor-driven stages (100 Â 100 Â 50 mm 3 ) designed for high resolution and throughput 3D micro/ nanofabrication. It enables rapid prototyping out of most polymers up to cm in scale with submicrometer spatial resolution. This can be used for production of three-dimensional artificial polymeric scaffolds applied for cell growth and expansion experiments as well as tissue engineering. Biocompatibilities of different acrylate, hybrid organic-inorganic and biodegradable polymeric materials were evaluated experimentally in vitro. Various in size and form scaffolds of biocompatible photopolymers were successfully fabricated having intricate 3D geometry, thus demonstrating the potential of the applied method. Adult rabbit myogenic stem cell proliferation tests show artificial scaffolds to be applicable for biomedical practice. Additionally, a micromolding technique was used for a rapid multiplication of adequate laser manufactured structures.
2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC), 2011
In this report we present experimental results on biocompatibility based on stem cell growth expe... more In this report we present experimental results on biocompatibility based on stem cell growth experiments in vitro as well as reaction of living organism to polymer implants in vivo of femtosecond laser 3D micro/nanostructurable photopolymers. A synergetic study on materials for rapid 3D scaffold fabrication having micrometer features and being centimeter in size, their biocompatibility in vitro and in vivo was done. The systematic study was performed providing consistent information which is important for further progress in cell growth and tissue engineering experiments. The chosen materials where of four different classes: well known biocompatible hybrid ORMO-CER (Ormocore b59, Micro Resist) [1], widely used biodegradable di-acrylated poly(ethylene)glycol (PEG-DA-258, Sigma-Aldrich) [2], pure acrylate AKRE (SR368, Sartomer) [3] and novel high quality laser structurable material ORMOSIL (SZ2080, FORTH) [4]. All of the materials were evaluated by their suitability for femtosecond laser structuring, which is well established as a technique enabling rapid and flexible production of 3D micro/nanostructures. All photopolymers could be 3D structured with < 1 µm resolution and up to cm in overall sizes, thus materializing the computer models of the scaffolds with required pore sizes and porosities. The typical dimensions of scaffolds were 5 x 5 x 0.5 mm 3 discs with 25 µm pore sizes and 40-60% porosity. Figure 1: Microscopic view of: a) adult stem cells (stained with PKH26) grown on the polymeric scaffold; b) histologic specimen of rabbit heart tissue surrounding polymeric implants after 3 weeks of implantation in heart atrium.
... Praėjus metams po operacijos, 86 proc. ligonių prieirdių vir-pėjimo neufiksuota. Tokius po... more ... Praėjus metams po operacijos, 86 proc. ligonių prieirdių vir-pėjimo neufiksuota. Tokius pooperacinio ritmo kitimo dėsningumus nurodo ir kiti tyrinėtojai. M. Pasic su ... First experience.) Medicina (Kaunas) 2001;37:1136-8. 17. Pasic M, Bergs P, Müller P, et al. ...
The Journal of Thoracic and Cardiovascular Surgery, 1990
March 1990 radiography, with special emphasis on the cardiothoracic ratio (normally 0.49); (2) M-... more March 1990 radiography, with special emphasis on the cardiothoracic ratio (normally 0.49); (2) M-mode echocardiography; (3) computed tomography of the chest; (4) transthoracic pericardiocentesis and fluid analysis with Sudan III staining and triglyceride analysis; (5) lymphangiography, with a goal to demonstrate a commun ication between lymphatic channels and the thoracic structures; and (6) oral administration triolein labeled with iodine 131 followed by (a) analysis of the pericardial fluid versus blood for radioactivity and (b) external cardiac imaging. The management of the aberrant chylous effusion often necessitates pericardiocentesis (which is both diagnostic and curative), pericardiectomy, thoracostomy drainage, and ligation or resection of the thoracic duct in the lower part of the chest. Dietary support dictates medium/small chain fatty acid/low fat meals.'
The Journal of Heart and Lung Transplantation, 2008
Background: The application of axial-flow pumps in patients with end-stage heart failure reveals ... more Background: The application of axial-flow pumps in patients with end-stage heart failure reveals a significantly reduced infectious complication rate as compared with rates observed with pulsatile devices. The remaining adverse event rate relates mainly to thromboembolic complications with neurologic consequences. We investigated the dependence of the neurologic adverse event rate on the length of the inflow cannula. Methods: A total of 216 consecutive patients with an axial-flow pump (INCOR; Berlin Heart GmbH, Berlin, Germany) were included in a retrospective multi-center analysis. In 138 patients, a short inflow cannula (24-mm tip length into the left ventricle), and in 78 patients a long inflow cannula (tip length 34 mm) was applied. Results: Patients with a long inflow cannula (LC) demonstrated a better survival rate than those with a short inflow cannula (SC) at the end of the observation period (LC, 63.4%; SC, 52.9%; p ϭ 0.05). The thromboembolic adverse event rate was also significantly lower. Only 3 of the 78 patients (3.8%) with an LC had a thromboembolic adverse event (thromboembolic events per patient-year ϭ 0.11) as compared with 32 (23.2%) of SC patients (thromboembolic events per patient-year ϭ 0.50, p Ͻ 0.001). Conclusions: Patients with a long inflow cannula had a better survival rate and a lower incidence of cerebrovascular adverse events than patients with a short inflow cannula.
It seems that mitral valve (MV) replacement technique is already standardized but still under dis... more It seems that mitral valve (MV) replacement technique is already standardized but still under discussion is the surgical approach. At Heart Surgery Clinic of Vilnius University MV replacement was started in 1970 (our total experience in valve surgery is 4396 operations). The most popular surgical approach was through left atrium (LA) from the right side. In cases with small atrium we used right atrial and transseptal and transverse transeptal biatrial (TTBA) approach. Left atrium approach is quite useful in many cases except those with small LA, LV hypertrophy and heart rotation when it can result a greater trauma for the heart, extended time of operation and, possibly, reduced performance after it. From September 1992 till May 1993 we used extended vertical transseptal (EVT) approach in 18 patients for MV replacement or repair, mitral and aortic valve replacement was performed for 5 patients, mitral valve replacement and tricuspid valvuloplasty for 13 patients, 5 patients had mitra...
It seems that mitral valve (MV) replacement technique is already standardized but still under dis... more It seems that mitral valve (MV) replacement technique is already standardized but still under discussion is the surgical approach. At Heart Surgery Clinic of Vilnius University MV replacement was started in 1970 (our total experience in valve surgery is 4396 operations). The most popular surgical approach was through left atrium (LA) from the right side. In cases with small atrium we used right atrial and transseptal and transverse transeptal biatrial (TTBA) approach. Left atrium approach is quite useful in many cases except those with small LA, LV hypertrophy and heart rotation when it can result a greater trauma for the heart, extended time of operation and, possibly, reduced performance after it. From September 1992 till May 1993 we used extended vertical transseptal (EVT) approach in 18 patients for MV replacement or repair, mitral and aortic valve replacement was performed for 5 patients, mitral valve replacement and tricuspid valvuloplasty for 13 patients, 5 patients had mitra...
We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimen... more We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimensional structuring for applications in tissue engineering. The direct laser writing system enables fabrication of artificial polymeric scaffolds over a large area (up to cm in lateral size) with sub-micrometer resolution which could find practical applications in biomedicine and surgery. Yb:KGW femtosecond laser oscillator (Pharos, Light Conversion. Co. Ltd.) is used as an irradiation source (75 fs, 515 nm (frequency doubled), 80 MHz). The sample is mounted on wide range linear motor driven stages having 10 nm sample positioning resolution (XY-ALS130-100, Z-ALS130-50, Aerotech, Inc.). These stages guarantee an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support the linear scanning speed up to 300 mm/s. By moving the sample three-dimensionally the position of laser focus in the photopolymer is changed and one is able to write complex 3D (three-dimensional) structures. An illumination system and CMOS camera enables online process monitoring. Control of all equipment is automated via custom made computer software ``3D-Poli'' specially designed for LTPP applications. Structures can be imported from computer aided design STereoLihography (stl) files or programmed directly. It can be used for rapid LTPP structuring in various photopolymers (SZ2080, AKRE19, PEG-DA-258) which are known to be suitable for bio-applications. Microstructured scaffolds can be produced on different substrates like glass, plastic and metal. In this paper, we present microfabricated polymeric scaffolds over a large area and growing of adult rabbit myogenic stem cells on them. Obtained results show the polymeric scaffolds to be applicable for cell growth practice. It exhibit potential to use it for artificial pericardium in the experimental model in the future.
Interactive CardioVascular and Thoracic Surgery, 2008
The purpose of this study was to evaluate sensitisation, occurring because of bridging with VAD, ... more The purpose of this study was to evaluate sensitisation, occurring because of bridging with VAD, and development of rejection episodes after transplantation in selected groups of patients using triple drug immunosuppression, without induction or desensitisation therapy. Sensitisation using standard complement dependent cytotoxicity was tested in 16 patients awaiting cardiac transplantation before VAD placement, one month post-implantation and on a six-monthly basis later on. Long-term (955"998 days) post-transplant course of six transplanted post-VAD patients was compared with 19 non-bridged recipients (follow-up time 1425"1273 days) of the same age. One-third of VAD recipients had developed anti-HLA antibodies one month post-implantation; 4y16 patients were sensitised six months after implantation. No de novo sensitisation development was revealed in VAD group post-transplantation. All sensitised patients independent of VAD placement underwent graft rejection episodes. Only 1 of 6 VAD recipient was treated because of grade 2R rejection, compared to 6y19 in the non-bridged group, Ps0.63. None of the patients had failed because of early graft rejection. In conclusion, VAD devices used in our centre cause low level risk for anti-HLA antibodies development. There were no differences in survival due to immunologic reasons between VAD bridged and non-bridged patients.
Interactive CardioVascular and Thoracic Surgery, 2006
Objective: The crucial decision to progress from pharmacological treatment of acute decompensated... more Objective: The crucial decision to progress from pharmacological treatment of acute decompensated heart failure to institution of assist device or transplantation begins with evaluation of the chances for a successful recovery. We tested whether the intra-aortic balloon counterpulsation (IABP) could give us the necessary time for clinical decision-making and preserve adequate circulation until it is made. Methods: We assessed 11 dilated cardiomyopathy patients of NYHA class IV, listed for heart transplantation or a ventricular assist device (VAD), who had conventional IABP placed. Heart function prior to and after IABP insertion as well as hemodynamics, end-organ function (renal and hepatic), frequency of complications and clinical outcomes were assessed. Results: The duration of intra-aortic balloon pump insertion ranged from 72 to 360 h (mean 181.54"81.65). After 48 h of intra-aortic balloon pump support, there was a significant increase of mean systemic arterial pressure from 74.5"9.6 to 82.3"4.7 mmHg (Ps0.02), and ejection fraction from 14.7"6.4 to 21.0"8.6 (Ps0.014). Meanwhile improvement of cardiac index, pulmonary wedge pressure and end-organ perfusion markers did not reach statistical significance. Three patients were successfully weaned off the balloon and recovered without additional interventions, two patients were transplanted and three were supported with counterpulsation until the implantation of assist device. Three patients died due to progressive heart failure, two after IABP removal and one after VAD implantation. There was no incidence of infection, limb ischemia, thrombus, or embolic complications. Conclusions: Our data showed that intra-aortic balloon pump support may be successfully and safely used in the acute decompensated dilated cardiomyopathy patients, as an urgent measure of cardiac support, to stabilize the patient and maintain organ perfusion until transplant is available, VAD is placed or patient is weaned from IABP.
Background: The Ross procedure has resolved the major problem in the management of aortic valve d... more Background: The Ross procedure has resolved the major problem in the management of aortic valve disease in the young, The operation can be performed in childhood and procedes an ideal valve substitute, which does not require anticoagulation, has growth potential and is free from degeneration. Methods: Short-and mid-term results of 45 patients after Ross procedure (December 1993 through April 1999) were reviewed. The aim of this study was to evaluate postoperative haemodynamic performance of this procedure, to asses the impact of modifications on postoperative results, and to make inferences that may improve results. Results. There were four early deaths (9%), no late deaths and no reoperations. Thirty-four patients had no or trivial symptoms, six patients had mild symptoms and one patient, moderate regurgitation of neo-aortic valve at the last echocardiographic study. Stenosis was not present at rest or during exercise. An obvious regression of left ventricle hypertrophy was detected (248 Ϯ 94-10 Ϯ 34 g/m). Reinforcement of the proximal suture line of the pulmonary autograft with pericardial strips does not restrict the growth of the aortic annulus. Dilatation of the aortic root was detected in all patients. The mean gradient through pulmonary homograft was 11.5 mmHg. Conclusions: The Ross procedure provides optimal haemodynamic function from the neoaortic valve, leading to regression of left ventricular hypertrophy and near normal life style, without anticoagulation. Dilatation of the neo-aortic root diameter postoperatively was not associated with progressing of regurgitation. Concern still exists over future valve function, particularly in patients with a diagnosis of bicuspid dilated incompetent aortic valves.
SummaryAtrial fibrillation (AF) is a common complication of coronary artery bypass grafting (CABG... more SummaryAtrial fibrillation (AF) is a common complication of coronary artery bypass grafting (CABG). We sought to determine the diagnostic validity of plasma biomarkers of i) inflammation (marked by interleukin-6 [IL-6] and high-sensitivity C-reactive protein [hs-CRP]), ii) extracellular matrix remodelling (matrix metalloproteinase [MMP-9], tissue inhibitor of matrix metalloproteinase [TIMP-1]) and iii) the prothrombotic state (tissue factor and von Willebrand factor [vWF]) in the risk prediction of post-operative AF. Samples were obtained preoperatively from peripheral/femoral vein and from intracardiac chambers (right atrium [RA], the right atrial appendage [RAA], the left atrium [LA] and the left atrial appendage [LAA]) amongst 100 consecutive patients free of AF and inflammatory disease undergoing elective CABG. Biomarker concentrations were related to incident AF (30 days). At 30 days post CABG, 30 patients were proven to have had AF. Concentrations of tissue factor (TF) and vWF...
Background: Atrial fibrillation (AF) is a common complication of coronary artery bypass grafting ... more Background: Atrial fibrillation (AF) is a common complication of coronary artery bypass grafting (CABG), and may have an inflammatory and/or thrombotic etiology. We sought to determine the expression of inflammatory (interleukin [IL]-6), thrombotic (tissue factor and von Willebrand factor [VWF]) and remodeling (matrix metalloproteinase [MMP]-9 and tissue inhibitor of metalloproteinase [TIMP]-1) markers by left atrial appendage (LAA) and right atrial appendage (RAA) tissue in the prediction of postoperative AF. We determined whether the tissue expression of markers of certain different pathophysiologic mechanisms predicted the development of AF after CABG. Methods: LAA and RAA tissue was excised during CABG in 100 patients free of AF and inflammation. Tissue marker expression was quantified by immunohistochemistry and was related to 30-day postoperative AF. Results: Overall, there were no significant differences in staining intensity of any marker between LAA tissue and RAA tissue. However, more intense expression of VWF by LAA tissue predicted the 30 patients with postoperative AF as compared with those free of AF (P = 0.006). IL-6, MMP-9 and TIMP-1 expression by RAA and LAA epicardial tissue was stronger than expression by endocardium or cardiomyocytes (all P < 0.025) but failed to predict AF. Conclusion: In this study, one of the largest to investigate tissue expression of pathophysiologic markers in relation to postoperative AF, we show that more intense expression of VWF by LAA tissue is a significant predictor of postoperative AF. This points towards a possible role of endothelial damage/dysfunction (as reflected by VWF changes) in the pathogenesis of postoperative AF.
The Journal of Heart and Lung Transplantation, 2008
Purpose: Right ventricular (RV) failure after left ventricular assist device (LVAD) placement is ... more Purpose: Right ventricular (RV) failure after left ventricular assist device (LVAD) placement is a serious complication with a poor prognosis and is difficult to predict. In the era of LVAD use as destination therapy and alternatives such as the total artificial heart, predicting post-LVAD RV failure requiring mechanical support is extremely important. Methods and Materials: We reviewed patient characteristics, laboratory values, and hemodynamic data from 266 patients who underwent LVAD placement at the University of Pennsylvania from April 1995 to June 2007. Results: Of 266 LVAD patients, 99 required RV assist device (BiVAD) placement (37%). We compared 36 parameters between LVAD (nϭ167) and BiVAD patients (nϭ99) to determine preoperative risk factors for RV assist device (RVAD) need. By univariate analysis, 23 variables showed statistically significant differences between the two groups (P Յ 0.05). The strongest of these were female gender, low body surface area, echocardiographic evidence of severe preoperative RV dysfunction, previous cardiac surgery, preoperative mechanical ventilation, elevated creatinine, elevated INR, elevated central venous pressure, low systolic blood pressure (SBP), low pulmonary artery systolic and mean pressures, low cardiac index (CI), low mixed venous oxygen saturation, and low right ventricular stroke work index (RVSWI). By multivariate logistic regression, CI Ͻ 2.3 L/min⅐m 2 (odds ratio [OR] 5.7), RVSWI Յ 0.25 mmHg⅐mL/m 2 (OR 5.1), severe preoperative RV dysfunction (OR 5.0), preoperative creatinine Ն 1.9 mg/dL (OR 4.8), previous cardiac surgery (OR 4.5), and SBP Յ 96 mmHg (OR 2.9) were the best predictors of RVAD need. Conclusions: The most significant predictors for RVAD need were CI, RVSWI, severe preoperative RV dysfunction, creatinine, previous cardiac surgery, and SBP. Using these factors, we have constructed an algorithm which can predict which LVAD patients will require RVAD with greater than 80% sensitivity and specificity.
The study assesses the impact of a program using a model of knowledge transfer on the long-term d... more The study assesses the impact of a program using a model of knowledge transfer on the long-term development of a pediatric cardiac service in Lithuania. A team from the United Kingdom evaluated Lithuanian pediatric cardiac services and provided support in areas targeted for improvement. The total number of infant operations performed in Lithuania from 1990 to 2008, together with in-hospital mortality rates, was broken down into 3 time periods and analyzed to estimate the efficacy of the program: (1) 1990-1998, before the program; (2) 1999-2002, during the program; (3) 2003-2008, following the end of the program. Lithuanian results in children older than 1 year were comparable with other European centers. However, only 315 infant and neonatal cardiac procedures were performed between 1990 and 1998, and there was an in-hospital mortality of 34.2%. Between 1999 and 2002, the UK team performed 23 highly complex demonstration procedures (in-hospital mortality, 13%). During the same period the Lithuanian team performed 305 additional operations in neonates and infants, and in-hospital mortality decreased to 18.7%. From 2003 to 2008 results continued to improve-559 infant operations were performed, with in-hospital mortality of 11.3% (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .0001). Knowledge transfer has led to substantial and sustainable long-term improvement in the results of infant cardiac surgery in Lithuania. Demonstrating techniques and care on a limited number of more complex cases is an efficient way of transferring knowledge and skills to the developing pediatric cardiac centers.
We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimen... more We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimensional structuring for applications in tissue engineering. The direct laser writing system enables fabrication of artificial polymeric scaffolds over a large area (up to cm in lateral size) with sub-micrometer resolution which could find practical applications in biomedicine and surgery. Yb:KGW femtosecond laser oscillator (Pharos, Light Conversion. Co. Ltd.) is used as an irradiation source (75 fs, 515 nm (frequency doubled), 80 MHz). The sample is mounted on wide range linear motor driven stages having 10 nm sample positioning resolution (XY-ALS130-100, Z-ALS130-50, Aerotech, Inc.). These stages guarantee an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support the linear scanning speed up to 300 mm/s. By moving the sample three-dimensionally the position of laser focus in the photopolymer is changed and one is able to write complex 3D (three-dimensional) structures. An illumination system and CMOS camera enables online process monitoring. Control of all equipment is automated via custom made computer software ``3D-Poli'' specially designed for LTPP applications. Structures can be imported from computer aided design STereoLihography (stl) files or programmed directly. It can be used for rapid LTPP structuring in various photopolymers (SZ2080, AKRE19, PEG-DA-258) which are known to be suitable for bio-applications. Microstructured scaffolds can be produced on different substrates like glass, plastic and metal. In this paper, we present microfabricated polymeric scaffolds over a large area and growing of adult rabbit myogenic stem cells on them. Obtained results show the polymeric scaffolds to be applicable for cell growth practice. It exhibit potential to use it for artificial pericardium in the experimental model in the future.
Biophotonics: Photonic Solutions For Better Health Care Ii, 2010
A tightly focused ultrafast pulsed laser beam is guided into the volume of the photosensitive mat... more A tightly focused ultrafast pulsed laser beam is guided into the volume of the photosensitive material and induces nonlinear photomodification. By translating the sample, the position of the focus is changed relatively, thus point-by-point complex 3D structures can be written inside the bulk. In this report, we present a Laser Two-Photon Polymerization (LTPP) setup for three-dimensional micro/nanostructuring for applications in photonics, microoptics, micromechanics, microfluidics and biomedicine. This system enables fabrication of functional devices over a large area (up to several cm in lateral size) with reproducible sub-micrometer resolution (up to 200 nm). In our experiments a Yb:KGW active media laser oscillator (75 fs, 200 kW, 515 nm frequency doubled, 80 MHz) was used as an irradiation source. The sample was mounted on XYZ wide range linear motor driven positioning stages having 10 nm positioning resolution. These stages enable an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support a linear scanning speed of up to 300 mm/s. Control of all the equipment was automated via custom made computer software "3D-Poli" specially designed for LTPP applications. The model of the structure can be imported as CAD file, this enables rapid and flexible structuring out of various photopolymers like ORMOCERs, ORMOSILs, acrylates and PEG-DAs which are commonly used in conventional UV mask, nanoimprint and µ-stereolithographies. In this paper, we demonstrate polymeric microstructures fabricated over a large area on glass, plastic and metal substrates. This opens a way to produce functional devices like photonic crystals, microlenses, micromechanic and microfluidic components and artificial scaffolds as templates for cell growth. Additionally, results of primary myogenic stem cells expanding on microfabricated polymeric scaffolds are provided. Cell proliferation tests show the material and structure to be biocompatible for the biomedical practice. Downloaded from SPIE Digital Library on 25 May 2010 to 78.61.217.42. Terms of Use: http://spiedl.org/terms Proc. of SPIE Vol. 7715 77151F-2 Downloaded from SPIE Digital Library on 25 May 2010 to 78.61.217.42. Terms of Use: http://spiedl.org/terms
In this work, we applied a constructed multi-photon polymerization system based on diode-pumped s... more In this work, we applied a constructed multi-photon polymerization system based on diode-pumped solid state femtosecond Yb:KGW laser used as pulsed irradiation light source (300 fs, 1030 nm, 200 kHz) in combination with large area high sample translation velocity (up to 300 mm/s) linear motor-driven stages (100 Â 100 Â 50 mm 3 ) designed for high resolution and throughput 3D micro/ nanofabrication. It enables rapid prototyping out of most polymers up to cm in scale with submicrometer spatial resolution. This can be used for production of three-dimensional artificial polymeric scaffolds applied for cell growth and expansion experiments as well as tissue engineering. Biocompatibilities of different acrylate, hybrid organic-inorganic and biodegradable polymeric materials were evaluated experimentally in vitro. Various in size and form scaffolds of biocompatible photopolymers were successfully fabricated having intricate 3D geometry, thus demonstrating the potential of the applied method. Adult rabbit myogenic stem cell proliferation tests show artificial scaffolds to be applicable for biomedical practice. Additionally, a micromolding technique was used for a rapid multiplication of adequate laser manufactured structures.
2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC), 2011
In this report we present experimental results on biocompatibility based on stem cell growth expe... more In this report we present experimental results on biocompatibility based on stem cell growth experiments in vitro as well as reaction of living organism to polymer implants in vivo of femtosecond laser 3D micro/nanostructurable photopolymers. A synergetic study on materials for rapid 3D scaffold fabrication having micrometer features and being centimeter in size, their biocompatibility in vitro and in vivo was done. The systematic study was performed providing consistent information which is important for further progress in cell growth and tissue engineering experiments. The chosen materials where of four different classes: well known biocompatible hybrid ORMO-CER (Ormocore b59, Micro Resist) [1], widely used biodegradable di-acrylated poly(ethylene)glycol (PEG-DA-258, Sigma-Aldrich) [2], pure acrylate AKRE (SR368, Sartomer) [3] and novel high quality laser structurable material ORMOSIL (SZ2080, FORTH) [4]. All of the materials were evaluated by their suitability for femtosecond laser structuring, which is well established as a technique enabling rapid and flexible production of 3D micro/nanostructures. All photopolymers could be 3D structured with < 1 µm resolution and up to cm in overall sizes, thus materializing the computer models of the scaffolds with required pore sizes and porosities. The typical dimensions of scaffolds were 5 x 5 x 0.5 mm 3 discs with 25 µm pore sizes and 40-60% porosity. Figure 1: Microscopic view of: a) adult stem cells (stained with PKH26) grown on the polymeric scaffold; b) histologic specimen of rabbit heart tissue surrounding polymeric implants after 3 weeks of implantation in heart atrium.
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