IDAGENE APARECIDA CESTARI
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
LIM/65, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/65, Hospital das Clínicas, Faculdade de Medicina - Líder
23 resultados
Resultados de Busca
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conferenceObject Mechanical Esophageal Displacement for Esophageal Safety of Mechanical Esophageal Displacement for Esophageal Thermal Injury Prevention During Atrial Fibrillation Ablation in Swine(2019) PEREIRA, Renner; PISANI, Cristiano F.; AIELLO, Vera; CESTARI, Idagene A.; MOURA, Daniel; CHOKR, Muhieddine; HARDY, Carina; SISSY, Melo; SCANAVACCA, Mauricio; HACHUL, Denise- Impact of Vacuum-Assisted Venous Drainage on Forward Flow in Simulated Pediatric Cardiopulmonary Bypass Circuits Utilizing a Centrifugal Arterial Pump Head(2020) GUIMARAES, Daniel Peres; CANEO, Luiz Fernando; MATTE, Gregory S.; CARLETTO, Luciana P.; POLICARPO, Valeria Camargo; CASTRO, Ana Vitoria C. X.; MIRANDA, Matheus H. C.; COSTA, Priscila S.; JATENE, Marcelo B.; CESTARI, Idagene; JATENE, Fabio B.Objective: To analyze the impact of vacuum-assisted venous drainage (VAVD) on arterial pump flow in a simulated pediatric cardiopulmonary bypass circuit utilizing a centrifugal pump (CP) with an external arterial filter. Methods: The simulation circuit consisted of a Quadrox-I Pediatric oxygenator, a Rotaflow CP (Maquet Cardiopulmonary AG, Rastatt, Germany), and a custom pediatric tubing set primed with Lactated Ringer's solution and packed red blood cells. Venous line pressure, reservoir pressure, and arterial flow were measured with VAVD turned off to record baseline values. Four other conditions were tested with progressively higher vacuum pressures (-20, -40, -60, and -80 mmHg) applied to the baseline cardiotomy pressure. An arterial filter was placed into the circuit and arterial flow was measured with the purge line in both open and closed positions. These trials were repeated at set arterial flow rates of 1500, 2000, and 2500 mL/min. Results: The use of progressively higher vacuum caused a reduction in effective arterial flow from 1490 +/- 0.00 to 590 +/- 0.00, from 2020 +/- 0.01 to 1220 +/- 0.00, and from 2490 +/- 0.0 to 1830 +/- 0.01 mL/min. Effective forward flow decreased with increased levels of VAVD. Conclusion: The use of VAVD reduces arterial flow when a CP is used as the main arterial pump. The reduction in the forward arterial flow increases as the vacuum level increases. The loss of forward flow is further reduced when the arterial filter purge line is kept in the recommended open position. An independent flow probe is essential to monitor pump flow during cardiopulmonary bypass.
- Early changes in myocyte contractility and cardiac function in streptozotocin-induced type 1 diabetes in rats(2020) MARCHINI, Gustavo S.; CESTARI, Ismar N.; SALEMI, Vera M. C.; IRIGOYEN, Maria Claudia; ARNOLD, Alexandre; KAKOI, Adelia; ROCON, Camila; AIELLO, Vera D.; CESTARI, Idagene A.Diabetes can elicit direct deleterious effects on the myocardium, independent of coronary artery disease or hypertension. These cardiac disturbances are termed diabetic cardiomyopathy showing increased risk of heart failure with or without reduced ejection fraction. Presently, there is no specific treatment for this type of cardiomyopathy and in the case of type I diabetes, it may start in early childhood independent of glycemic control. We hypothesized that alterations in isolated myocyte contractility and cardiac function are present in the early stages of experimental diabetes in rats before overt changes in myocardium structure occur. Diabetes was induced by single-dose injection of streptozotocin (STZ) in rats with data collected from control and diabetic animals 3 weeks after injection. Left ventricle myocyte contractility was measured by single-cell length variation under electrical stimulation. Cardiac function and morphology were studied by high-resolution echocardiography with pulsed-wave tissue Doppler imaging (TDI) measurements and three-lead surface electrocardiogram. Triglycerides, cholesterol and liver enzyme levels were measured from plasma samples obtained from both groups. Myocardial collagen content and perivascular fibrosis of atria and ventricle were studied by histological analysis after picrosirius red staining. Diabetes resulted in altered contractility of isolated cardiac myocytes with increased contraction and relaxation time intervals. Echocardiography showed left atrium dilation, increased end-diastolic LV and posterior wall thickness, with reduced longitudinal systolic peak velocity (S') of the septum mitral annulus at the apical four-chamber view obtained by TDI. Triglycerides, aspartate aminotransferase and alkaline phosphatase were elevated in diabetic animals. Intertitial collagen content was higher in atria of both groups and did not differ among control and diabetic animals. Perivascular intramyocardial arterioles collagen did not differ between groups. These results suggest that alterations in cardiac function are present in the early phase in this model of diabetes type 1 and occur before overt changes in myocardium structure appear as evaluated by intersticial collagen deposition and perivascular fibrosis of intramyocardial arterioles.
conferenceObject Comparative Study between Cavopulmonary Anastomosis Associated with Left Ventricular Assist Device Support and Biventricular Circulatory Assistance in Acute Biventricular Failure(2012) SANTOS, L. A. S.; MOREIRA, L. F. P.; BENICIO, A.; CESTARI, I.; MATTOS JR., E.; STOLF, N. G.Purpose: Right ventricular failure during left ventricular assist device (LVAD) support can result in severe hemodynamic compromise with high mortality. This study investigated the acute effects of cavopulmonary anastomosis on LVAD performance and right ventricular myocardial compromise in comparison with biventricular circulatory support, in a model of severe biventricular failure. Methods and Materials: LVAD support was performed by means of centrifugal pump implantation in 21 anesthetized pigs (20-30 kg) with biventricular failure obtained by ventricular fibrillation induction. Animals were randomized to be submitted to modified cavopulmonary anastomosis, to biventricular circulatory support or to control group. They were maintained under circulatory support and hemodynamic monitoring for 3h. Venous lactate and cytokines serum levels were also determined. Endocardium samples of the ventricles were collected and analyzed by electronic microscopy. Results: Ventricular fibrillation was responsible for acute LVAD performance impairment after 180 min in the control group. Cavopulmonary anastomosis resulted in non-significant improvement of LVAD pump flow in relation to control group (+55±14 ml/kg/min, p=0.072), while animals under biventricular support maintained higher LVAD flow performance (+93±17 ml/kg/min, p=0.012). Mean arterial pressure remained constant only in biventricular group (p<0.001), which also presented significant decrease of right atrial and ventricular pressures. Similar increases in lactate and cytokines levels were observed in the three groups. Ultrastructural analysis documented the presence of higher levels of myocardial mitochondrial swelling in control group (p=0.018). Conclusions: Concomitant use of cavopulmonary anastomosis during LVAD support in a pig model of severe biventricular failure resulted in non-significant improvement of hemodynamic performance and it did not effectively replace the use of biventricular support.- Effect of the bileaflet inlet valve angle on the flow of a pediatric ventricular assist device: Experimental analysis(2022) LEMOS, Bernardo Luiz Harry Diniz; BORTOLIN, Vitor Augusto Andreghetto; AMARAL, Rodrigo de Lima; MAZZETTO, Marcelo; CESTARI, Idagene Aparecida; MENEGHINI, Julio RomanoBackground Mechanical heart valves (MHV) and its fluid dynamics inside a pulsatile pediatric ventricular assist device (PVAD) can be associated with blood degradation. In this article, flow structures are analyzed and compared by an experimental investigation on the effect of bileaflet MHV positioned at varying angles in the inlet port orifice of a PVAD. Methods Time-resolved particle image velocimetry was applied to characterize the internal flow of the device. St Jude Medical bileaftlet valves were used on the inlet orifice and positioned at 0 degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, and 90 degrees in relation to the centerline of the device. Three planes with bidimensional velocity magnitude fields were considered in the analysis with visualization of diastolic jets, device wall washing patterns and flow circulation during emptying or systole of the pump. Also, the washing vortex area, and vertical velocity probabilities of regurgitant flows in the inlet valve were evaluated. Results The results show that a variation in the angle of the MHV at the inlet port produced distinct velocities, fluid structures, and regurgitant flow probabilities within the device. MHV positioned at an angle of 0 degrees generated the strongest inlet jet, larger vortex area during filling, more prominent outgoing flow, and less regurgitation compared to the angles studied. The presence of unfavorable fluid structures, such as small vortices, and/or sudden flow structure interruption, and/or regurgitation, were identified at 45 degrees and 90 degrees angles. Conclusions The 0 degrees inlet angle had better outcomes than other angles due to its consistency in the multiple parameters analyzed.
- Functional Performance of Different Venous Limb Options in Simulated Neonatal/Pediatric Cardiopulmonary Bypass Circuits(2018) CANEO, Luiz Fernando; MATTE, Gregory S.; GUIMARAES, Daniel Peres; VIOTTO, Guilherme; MAZZETO, Marcelo; CESTARI, Idagene; NEIROTTI, Rodolfo A.; JATENE, Marcelo B.; WANG, Shigang; UNDAR, Akif; CHANG JUNIOR, Joao; JATENE, Fabio B.Objective: Hemodilution is a concern in cardiopulmonary bypass (CPB). Using a smaller dual tubing rather than a single larger inner diameter (ID) tubing in the venous limb to decrease prime volume has been a standard practice. The purpose of this study is to evaluate these tubing options. Methods: Four different CPB circuits primed with blood (hematocrit 30%) were investigated. Two setups were used with two circuits for each one. In Setup I, a neonatal oxygenator was connected to dual 3/16"" ID venous limbs (Circuit A) or to a single 1/4"" ID venous limb (Circuit B); and in Setup II, a pediatric oxygenator was connected to dual 1/4"" ID venous limbs (Circuit C) or a single 3/8"" ID venous limb (Circuit D). Trials were conducted at arterial flow rates of 500 ml/min up to 1500 ml/min (Setup I) and up to 3000 ml/min (Setup II), at 36 degrees C and 28 degrees C. Results: Circuit B exhibited a higher venous flow rate than Circuit A, and Circuit D exhibited a higher venous flow rate than Circuit C, at both temperatures. Flow resistance was significantly higher in Circuits A and C than in Circuits B (P<0.001) and D (P<0.001), respectively. Conclusion: A single 1/4"" venous limb is better than dual 3/16"" venous limbs at all flow rates, up to 1500 ml/min. Moreover, a single 3/8"" venous limb is better than dual 1/4"" venous limbs, up to 3000 ml/min. Our findings strongly suggest a revision of perfusion practice to include single venous limb circuits for CPB.
- The Distensibility of the Human Vena Cava and Its Importance to In Vitro Studies of Venous Compression Syndromes: A Search for a Suitable Polymer for 3-Dimensional Printing(2023) PUECH-LEAO, Pedro; TORRES, Inez O.; SILVA, Erasmo S. da; CESTARI, Ismar N.; CESTARI, Idagene A.; ROSA, Jhenyfer M. da; NAHAS, William C.; LUCCIA, Nelson DeBackground: Venous compression syndromes are clinical conditions in which the large veins are compressed by other anatomical structures. Laboratory simulations may help us better understand the hemodynamics in venous compressions by creating situations similar to those seen in vivo. The aim of this study is to produce a model of the caval bifurcation using a polymer with distensibility similar to the human vena cava. Methods: Fragments of the inferior vena cava were collected from 13 deceased kidney donors (aged 15-37 years) and were tested for deformation (strain) when subjected to distension at 50 N/cm2. Strips of 5 different polymers-thermic polyurethane and Agilus30 with Vero Magenta (AV) (in 3 different hardnesses) and silicone-were subjected to the same biomechanical tests and compared with the vena cava. A model of the caval bifurcation was produced with 3-D printing. Results: The deformation (strain) of the vena cava wall was 0.16 & PLUSMN; 0.9 when submitted to stress close to 50 N/cm2. Silicone showed a strain higher than the standard deviation of venous fragments. The strain of AV resin 95 Shore was lower than the standard deviation of the venous fragments. AV Resins 70 and 85 Shore showed strains within the standard deviation of the venous specimen, with 70 Shore being closest to the mean venous strain. Therefore, this material was selected for modeling the caval bifurcation. The computed tomography scan image generated a computer model of the caval bifurcation and was printed in 3 dimensions. In addition, the segments of 2 adjacent vertebrae were also printed to reference the compression site. Conclusions: The 3-D printing of large veins can produce models with anatomy and biome-chanics similar to those of human veins and opens a field of investigation into the hemody-namics of venous compression syndromes. Polymers with Shore A70 appear to have biomechanical properties similar to those of the vena cava wall. The model obtained in this study can be used in several in vitro studies of May-Thurner Syndrome.
- A new approach to heart valve tissue engineering: mimicking the heart ventricle with a ventricular assist device in a novel bioreactor(2011) KAASI, Andreas; CESTARI, Idagene A.; STOLF, Noedir A. G.; LEIRNER, Adolfo A.; HASSAGER, Ole; CESTARI, Ismar N.The 'biomimetic' approach to tissue engineering usually involves the use of a bioreactor mimicking physiological parameters whilst supplying nutrients to the developing tissue. Here we present a new heart valve bioreactor, having as its centrepiece a ventricular assist device (VAD), which exposes the cell-scaffold constructs to a wider array of mechanical forces. The pump of the VAD has two chambers: a blood and a pneumatic chamber, separated by an elastic membrane. Pulsatile air-pressure is generated by a piston-type actuator and delivered to the pneumatic chamber, ejecting the fluid in the blood chamber. Subsequently, applied vacuum to the pneumatic chamber causes the blood chamber to fill. A mechanical heart valve was placed in the VAD's inflow position. The tissue engineered (TE) valve was placed in the outflow position. The VAD was coupled in series with a Windkessel compliance chamber, variable throttle and reservoir, connected by silicone tubings. The reservoir sat on an elevated platform, allowing adjustment of ventricular preload between 0 and 11 mmHg. To allow for sterile gaseous exchange between the circuit interior and exterior, a 0.2 mu m filter was placed at the reservoir. Pressure and flow were registered downstream of the TE valve. The circuit was filled with culture medium and fitted in a standard 5% CO(2) incubator set at 37 degrees C. Pressure and flow waveforms were similar to those obtained under physiological conditions for the pulmonary circulation. The 'cardiomimetic' approach presented here represents a new perspective to conventional biomimetic approaches in TE, with potential advantages.
- In Vitro Evaluation of Pediatric Hollow-Fiber Membrane Oxygenators on Hemodynamic Performance and Gaseous Microemboli Handling: An International Multicenter/Multidisciplinary Approach(2017) WANG, Shigang; CANEO, Luiz F.; JATENE, Marcelo B.; JATENE, Fabio B.; CESTARI, Idagene A.; KUNSELMAN, Allen R.; UNDAR, AkifThe objective of this study was to compare the hemodynamic performances and gaseous microemboli (GME) handling ability of two pediatric oxygenators in a simulated pediatric cardiopulmonary bypass (CPB) model and the importance of adding an arterial filter in the circuit. The circuit consisted of a Braile Infant oxygenator or a Maquet Quadrox-I Pediatric oxygenator without integrated arterial filter (parallel arrangement), 1/4 in. ID tubing A-V loop, and a 12-Fr arterial cannula, primed with lactated Ringer's solution and packed red blood cells. Trials were conducted at flow rates ranging from 500 to 2000 mL/min (500 mL/min increment) at 35 degrees C and 28 degrees C. Real-time pressure and flow data were recorded using a custom-based data acquisition system. ForGME testing, 5 cc of air was manually injected into the venous line. GME were recorded using the Emboli Detection and Classification Quantifier (EDAC) System. An additional experiment using a separate arterial filter was conducted. There was no difference in the mean circuit pressure, pressure drop, total hemodynamic energy level, and energy loss between the two oxygenators. The venous line pressures were higher in the Braile than in the Quadrox group during all trials (P < 0.01). GME count and volume at pre-/post oxygenator and pre-cannula sites in the Quadrox were lower than the Braile group at high flow rates (P<0.05). In the additional experiment, an arterial filter captured a significant number of microemboli at all flow rates. The Braile Infant oxygenator has a matched hemodynamic characteristic with the Quadrox-i Pediatric oxygenator. The Quadrox-i has a better GME handling ability compared with the Braile Infant oxygenator. Regardless of type of oxygenator an additional arterial filter decreases the number of GME.
conferenceObject Biomechanical Properties of the Porcine Trachea before and after Decellularization for Airway Transplantation(2021) GUIMARAES, A. B.; CORREA, A. T.; PEGO-FERNANDES, P. M.; MAIZATO, M. J.; CESTARI, I. A.; CARDOSO, P. F.
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