RONALDO HONORATO BARROS DOS SANTOS

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Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico

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Agora exibindo 1 - 10 de 17
  • article 25 Citação(ões) na Scopus
    Polymorphism in the Alpha Cardiac Muscle Actin 1 Gene Is Associated to Susceptibility to Chronic Inflammatory Cardiomyopathy
    (2013) FRADE, Amanda Farage; TEIXEIRA, Priscila Camilo; IANNI, Barbara Maria; PISSETTI, Cristina Wide; SABA, Bruno; WANG, Lin Hui Tzu; KURAMOTO, Andreia; NOGUEIRA, Luciana Gabriel; BUCK, Paula; DIAS, Fabricio; GINIAUX, Helene; LLORED, Agnes; ALVES, Sthefanny; SCHMIDT, Andre; DONADI, Eduardo; MARIN-NETO, Jose Antonio; HIRATA, Mario; SAMPAIO, Marcelo; FRAGATA, Abilio; BOCCHI, Edimar Alcides; STOLF, Antonio Noedir; FIORELLI, Alfredo Inacio; SANTOS, Ronaldo Honorato Barros; RODRIGUES, Virmondes; PEREIRA, Alexandre Costa; KALIL, Jorge; CUNHA-NETO, Edecio; CHEVILLARD, Christophe
    Aims: Chagas disease, caused by the protozoan Trypanosoma cruzi is endemic in Latin America, and may lead to a life-threatening inflammatory dilated, chronic Chagas cardiomyopathy (CCC). One third of T. cruzi-infected individuals progress to CCC while the others remain asymptomatic (ASY). A possible genetic component to disease progression was suggested by familial aggregation of cases and the association of markers of innate and adaptive immunity genes with CCC development. Since mutations in multiple sarcomeric genes, including alpha-cardiac actin (ACTC1) have been involved in hereditary dilated cardiomyopathy, we investigated the involvement of the ACTC1 gene in CCC pathogenesis. Methods and Results: We conducted a proteomic and genetic study on a Brazilian study population. The genetic study was done on a main cohort including 118 seropositive asymptomatic subjects and 315 cases and the replication was done on 36 asymptomatic and 102 CCC cases. ACTC1 protein and mRNA levels were lower in myocardial tissue from patients with end-stage CCC than those found in hearts from organ donors. Genotyping a case-control cohort of CCC and ASY subjects for all informative single nucleotide polymorphism (SNP) in the ACTC1 gene identified rs640249 SNP, located at the 5' region, as associated to CCC. Associations are borderline after correction for multiple testing. Correlation and haplotype analysis led to the identification of a susceptibility haplotype. Functional assays have shown that the rs640249A/C polymorphism affects the binding of transcriptional factors in the promoter regions of the ACTC1 gene. Confirmation of the detected association on a larger independent replication cohort will be useful. Conclusions: Genetic variations at the ACTC1 gene may contribute to progression to chronic Chagas Cardiomyopathy among T. cruzi-infected patients, possibly by modulating transcription factor binding to ACTC1 promoter regions.
  • article 51 Citação(ões) na Scopus
    Myocardial Gene Expression of T-bet, GATA-3, Ror-gamma t, FoxP3, and Hallmark Cytokines in Chronic Chagas Disease Cardiomyopathy: An Essentially Unopposed T(H)1-Type Response
    (2014) NOGUEIRA, Luciana Gabriel; SANTOS, Ronaldo Honorato Barros; FIORELLI, Alfredo Inacio; MAIRENA, Eliane Conti; BENVENUTI, Luiz Alberto; BOCCHI, Edimar Alcides; STOLF, Noedir Antonio; KALIL, Jorge; CUNHA-NETO, Edecio
    Background. Chronic Chagas disease cardiomyopathy (CCC), a late consequence of Trypanosoma cruzi infection, is an inflammatory cardiomyopathy with prognosis worse than those of noninflammatory etiology (NIC). Although the T cell-rich myocarditis is known to play a pathogenetic role, the relative contribution of each of the functional T cell subsets has never been thoroughly investigated. We therefore assessed gene expression of cytokines and transcription factors involved in differentiation and effector function of each functional T cell subset (T(H)1/T(H)2/T(H)17/Treg) in CCC, NIC, and heart donor myocardial samples. Methods and Results. Quantitative PCR showed markedly upregulated expression of IFN-gamma and transcription factor T-bet, and minor increases of GATA-3; FoxP3 and CTLA-4; IL-17 and IL-18 in CCC as compared with NIC samples. Conversely, cytokines expressed by T(H)2 cells (IL-4, IL-5, and IL-13) or associated with Treg (TGF-beta and IL-10) were not upregulated in CCC myocardium. Expression of T(H)1-related genes such as T-bet, IFN-gamma, and IL-18 correlated with ventricular dilation, FoxP3, and CTLA-4. Conclusions. Results are consistent with a strong local T(H)1-mediated response in most samples, possibly associated with pathological myocardial remodeling, and a proportionally smaller FoxP3(+)CTLA4(+) Treg cell population, which is unable to completely curb IFN-gamma production in CCC myocardium, therefore fueling inflammation.
  • article 6 Citação(ões) na Scopus
    Sildenafil vs. Sodium Nitroprusside for the Pulmonary Hypertension Reversibility Test Before Cardiac Transplantation
    (2012) FREITAS JR., Aguinaldo Figueiredo; BACAL, Fernando; OLIVEIRA JUNIOR, Jose de Lima; FIORELLI, Alfredo Inacio; SANTOS, Ronaldo Honorato; MOREIRA, Luiz Felipe Pinho; SILVA, Christiano Pereira; MANGINI, Sandrigo; TSUTSUI, Jeane Mike; BOCCHI, Edimar Alcides
    Background: Pulmonary hypertension is associated with a worse prognosis after cardiac transplantation. The pulmonary hypertension reversibility test with sodium nitroprusside (SNP) is associated with a high rate of systemic arterial hypotension, ventricular dysfunction of the transplanted graft and high rates of disqualification from transplantation. Objective: This study was aimed at comparing the effects of sildenafil (SIL) and SNP on hemodynamic, neurohormonal and echocardiographic variables during the pulmonary reversibility test. Methods: The patients underwent simultaneously right cardiac catheterization, echocardiography, BNP measurement, and venous blood gas analysis before and after receiving either SNP (1 - 2 mu g/kg/min) or SIL (100 mg, single dose). Results: Both drugs reduced pulmonary hypertension, but SNP caused a significant systemic hypotension (mean blood pressure - MBP: 85.2 vs. 69.8 mm Hg; p < 0.001). Both drugs reduced cardiac dimensions and improved left cardiac function (SNP: 23.5 vs. 24.8%, p = 0.02; SIL: 23.8 vs. 26%, p < 0.001) and right cardiac function (SIL: 6.57 +/- 2.08 vs. 8.11 +/- 1.81 cm/s, p = 0.002; SNP: 6.64 +/- 1.51 vs. 7.72 +/- 1.44 cm/s, p = 0.003), measured through left ventricular ejection fraction and tissue Doppler, respectively. Sildenafil, contrary to SNP, improved venous oxygen saturation, measured on venous blood gas analysis. Conclusion: Sildenafil and SNP are vasodilators that significantly reduce pulmonary hypertension and cardiac geometry, in addition to improving biventricular function. Sodium nitroprusside, contrary to SIL, was associated with systemic arterial hypotension and worsening of venous oxygen saturation. (Arq Bras Cardiol 2012;99(3):848-856)
  • article 24 Citação(ões) na Scopus
    Selective Decrease of Components of the Creatine Kinase System and ATP Synthase Complex in Chronic Chagas Disease Cardiomyopathy
    (2011) TEIXEIRA, Priscila Camillo; SANTOS, Ronaldo Honorato Barros; FIORELLI, Alfredo Inacio; BILATE, Angelina Morand Bianchi; BENVENUTI, Luiz Alberto; STOLF, Noedir Antonio; KALIL, Jorge; CUNHA-NETO, Edecio
    Background: Chronic Chagas disease cardiomyopathy (CCC) is an inflammatory dilated cardiomyopathy with a worse prognosis than other cardiomyopathies. CCC occurs in 30 % of individuals infected with Trypanosoma cruzi, endemic in Latin America. Heart failure is associated with impaired energy metabolism, which may be correlated to contractile dysfunction. We thus analyzed the myocardial gene and protein expression, as well as activity, of key mitochondrial enzymes related to ATP production, in myocardial samples of end-stage CCC, idiopathic dilated (IDC) and ischemic (IC) cardiomyopathies. Methodology/Principal Findings: Myocardium homogenates from CCC (N = 5), IC (N = 5) and IDC (N = 5) patients, as well as from heart donors (N = 5) were analyzed for protein and mRNA expression of mitochondrial creatine kinase (CKMit) and muscular creatine kinase (CKM) and ATP synthase subunits aplha and beta by immunoblotting and by real-time RT-PCR. Total myocardial CK activity was also assessed. Protein levels of CKM and CK activity were reduced in all three cardiomyopathy groups. However, total CK activity, as well as ATP synthase alpha chain protein levels, were significantly lower in CCC samples than IC and IDC samples. CCC myocardium displayed selective reduction of protein levels and activity of enzymes crucial for maintaining cytoplasmic ATP levels. Conclusions/Significance: The selective impairment of the CK system may be associated to the loss of inotropic reserve observed in CCC. Reduction of ATP synthase alpha levels is consistent with a decrease in myocardial ATP generation through oxidative phosphorylation. Together, these results suggest that the energetic deficit is more intense in the myocardium of CCC patients than in the other tested dilated cardiomyopathies.
  • article 82 Citação(ões) na Scopus
    MicroRNAs miR-1, miR-133a, miR-133b, miR-208a and miR-208b are dysregulated in Chronic Chagas disease Cardiomyopathy
    (2014) FERREIRA, Ludmila Rodrigues Pinto; FRADE, Amanda Farage; SANTOS, Ronaldo Honorato Barros; TEIXEIRA, Priscila Camillo; BARON, Monique Andrade; NAVARRO, Isabela Cunha; BENVENUTI, Luiz Alberto; FIORELLI, Alfredo Inacio; BOCCHI, Edimar Alcides; STOLF, Noedir Antonio; CHEVILLARD, Christophe; KALIL, Jorge; CUNHA-NETO, Edecio
    Background/methods: Chagas disease is caused by an intracellular parasite, Trypanosoma cruzi, and it is a leading cause of heart failure in Latin America. The main clinical consequence of the infection is the development of a Chronic Chagas disease Cardiomyopathy (CCC), which is characterized by myocarditis, hypertrophy and fibrosis and affects about 30% of infected patients. CCC has a worse prognosis than other cardiomyopathies, like idiopathic dilated cardiomyopathy (DCM). It is well established that myocardial gene expression patterns are altered in CCC, but the molecular mechanisms underlying these differences are not clear. MicroRNAs are recently discovered regulators of gene expression, and are recognized as important factors in heart development and cardiovascular disorders (CD). We analyzed the expression of nine different miRNAs inmyocardial tissue samples of CCC patients in comparison to DCM patients and samples from heart transplant donors. Using the results of a cDNA microarray database on CCC and DCM myocardium, signaling networks were built and nodal molecules were identified. Results: We observed that five miRNAs were significantly altered in CCC and three in DCM; importantly, three miRNAs were significantly reduced in CCC as compared to DCM. We observed that multiple gene targets of the differentially expressed miRNAs showed a concordant inverse expression in CCC. Significantly, most gene targets and involved networks belong to crucial disease-related signaling pathways. Conclusion: These results suggest that miRNAs may play a major role in the regulation of gene expression in CCC pathogenesis, with potential implication as diagnostic and prognostic tools.
  • article 11 Citação(ões) na Scopus
    Impairment of Multiple Mitochondrial Energy Metabolism Pathways in the Heart of Chagas Disease Cardiomyopathy Patients
    (2021) TEIXEIRA, Priscila Camillo; DUCRET, Axel; LANGEN, Hanno; NOGOCEKE, Everson; SANTOS, Ronaldo Honorato Barros; NUNES, Joao Paulo Silva; BENVENUTI, Luiz; LEVY, Debora; BYDLOWSKI, Sergio Paulo; BOCCHI, Edimar Alcides; TAKARA, Andreia Kuramoto; FIORELLI, Alfredo Inacio; STOLF, Noedir Antonio; POMERANZEFF, Pablo; CHEVILLARD, Christophe; KALIL, Jorge; CUNHA-NETO, Edecio
    Chagas disease cardiomyopathy (CCC) is an inflammatory dilated cardiomyopathy occurring in 30% of the 6 million infected with the protozoan Trypanosoma cruzi in Latin America. Survival is significantly lower in CCC than ischemic (IC) and idiopathic dilated cardiomyopathy (DCM). Previous studies disclosed a selective decrease in mitochondrial ATP synthase alpha expression and creatine kinase activity in CCC myocardium as compared to IDC and IC, as well as decreased in vivo myocardial ATP production. Aiming to identify additional constraints in energy metabolism specific to CCC, we performed a proteomic study in myocardial tissue samples from CCC, IC and DCM obtained at transplantation, in comparison with control myocardial tissue samples from organ donors. Left ventricle free wall myocardial samples were subject to two-dimensional electrophoresis with fluorescent labeling (2D-DIGE) and protein identification by mass spectrometry. We found altered expression of proteins related to mitochondrial energy metabolism, cardiac remodeling, and oxidative stress in the 3 patient groups. Pathways analysis of proteins differentially expressed in CCC disclosed mitochondrial dysfunction, fatty acid metabolism and transmembrane potential of mitochondria. CCC patients' myocardium displayed reduced expression of 22 mitochondrial proteins belonging to energy metabolism pathways, as compared to 17 in DCM and 3 in IC. Significantly, 6 beta-oxidation enzymes were reduced in CCC, while only 2 of them were down-regulated in DCM and 1 in IC. We also observed that the cytokine IFN-gamma, previously described with increased levels in CCC, reduces mitochondrial membrane potential in cardiomyocytes. Results suggest a major reduction of mitochondrial energy metabolism and mitochondrial dysfunction in CCC myocardium which may be in part linked to IFN-gamma. This may partially explain the worse prognosis of CCC as compared to DCM or IC.
  • article 87 Citação(ões) na Scopus
    Myocardial Chemokine Expression and Intensity of Myocarditis in Chagas Cardiomyopathy Are Controlled by Polymorphisms in CXCL9 and CXCL10
    (2012) NOGUEIRA, Luciana Gabriel; SANTOS, Ronaldo Honorato Barros; IANNI, Barbara Maria; FIORELLI, Alfredo Inacio; MAIRENA, Eliane Conti; BENVENUTI, Luiz Alberto; FRADE, Amanda; DONADI, Eduardo; DIAS, Fabricio; SABA, Bruno; WANG, Hui-Tzu Lin; FRAGATA, Abilio; SAMPAIO, Marcelo; HIRATA, Mario Hiroyuki; BUCK, Paula; MADY, Charles; BOCCHI, Edimar Alcides; STOLF, Noedir Antonio; KALIL, Jorge; CUNHA-NETO, Edecio
    Background: Chronic Chagas cardiomyopathy (CCC), a life-threatening inflammatory dilated cardiomyopathy, affects 30% of the approximately 8 million patients infected by Trypanosoma cruzi. Even though the Th1 T cell-rich myocarditis plays a pivotal role in CCC pathogenesis, little is known about the factors controlling inflammatory cell migration to CCC myocardium. Methods and Results: Using confocal immunofluorescence and quantitative PCR, we studied cell surface staining and gene expression of the CXCR3, CCR4, CCR5, CCR7, CCR8 receptors and their chemokine ligands in myocardial samples from end-stage CCC patients. CCR5+, CXCR3+, CCR4+, CCL5+ and CXCL9+ mononuclear cells were observed in CCC myocardium. mRNA expression of the chemokines CCL5, CXCL9, CXCL10, CCL17, CCL19 and their receptors was upregulated in CCC myocardium. CXCL9 mRNA expression directly correlated with the intensity of myocarditis, as well as with mRNA expression of CXCR3, CCR4, CCR5, CCR7, CCR8 and their ligands. We also analyzed single-nucleotide polymorphisms for genes encoding the most highly expressed chemokines and receptors in a cohort of Chagas disease patients. CCC patients with ventricular dysfunction displayed reduced genotypic frequencies of CXCL9 rs10336 CC, CXCL10 rs3921 GG, and increased CCR5 rs1799988CC as compared to those without dysfunction. Significantly, myocardial samples from CCC patients carrying the CXCL9/CXCL10 genotypes associated to a lower risk displayed a 2-6 fold reduction in mRNA expression of CXCL9, CXCL10, and other chemokines and receptors, along with reduced intensity of myocarditis, as compared to those with other CXCL9/CXCL10 genotypes. Conclusions: Results may indicate that genotypes associated to reduced risk in closely linked CXCL9 and CXCL10 genes may modulate local expression of the chemokines themselves, and simultaneously affect myocardial expression of other key chemokines as well as intensity of myocarditis. Taken together our results may suggest that CXCL9 and CXCL10 are master regulators of myocardial inflammatory cell migration, perhaps affecting clinical progression to the life-threatening form of CCC.
  • article 3 Citação(ões) na Scopus
    Epigenetic regulation of transcription factor binding motifs promotes Th1 response in Chagas disease cardiomyopathy
    (2022) BROCHET, Pauline; IANNI, Barbara Maria; LAUGIER, Laurie; FRADE, Amanda Farage; NUNES, Joao Paulo Silva; TEIXEIRA, Priscila Camillo; MADY, Charles; FERREIRA, Ludmila Rodrigues Pinto; FERRE, Quentin; SANTOS, Ronaldo Honorato Barros; KURAMOTO, Andreia; CABANTOUS, Sandrine; STEFFEN, Samuel; STOLF, Antonio Noedir; POMERANTZEFF, Pablo; FIORELLI, Alfredo Inacio; BOCCHI, Edimar Alcides; PISSETTI, Cristina Wide; SABA, Bruno; CANDIDO, Darlan da Silva; DIAS, Fabricio C.; SAMPAIO, Marcelo Ferraz; GAIOTTO, Fabio Antonio; MARIN-NETO, Jose Antonio; FRAGATA, Abilio; ZANIRATTO, Ricardo Costa Fernandes; SIQUEIRA, Sergio; PEIXOTO, Giselle De Lima; RIGAUD, Vagner Oliveira-Carvalho; BACAL, Fernando; BUCK, Paula; ALMEIDA, Rafael Ribeiro; LIN-WANG, Hui Tzu; SCHMIDT, Andre; MARTINELLI, Martino; HIRATA, Mario Hiroyuki; DONADI, Eduardo Antonio; PEREIRA, Alexandre Costa; RODRIGUES JUNIOR, Virmondes; PUTHIER, Denis; KALIL, Jorge; SPINELLI, Lionel; CUNHA-NETO, Edecio; CHEVILLARD, Christophe
    Chagas disease, caused by the protozoan Trypanosoma cruzi, is an endemic parasitic disease of Latin America, affecting 7 million people. Although most patients are asymptomatic, 30% develop complications, including the often-fatal Chronic Chagasic Cardiomyopathy (CCC). Although previous studies have demonstrated some genetic deregulations associated with CCCs, the causes of their deregulations remain poorly described. Based on bulk RNA-seq and whole genome DNA methylation data, we investigated the genetic and epigenetic deregulations present in the moderate and severe stages of CCC. Analysis of heart tissue gene expression profile allowed us to identify 1407 differentially expressed transcripts (DEGs) specific from CCC patients. A tissue DNA methylation analysis done on the same tissue has permitted the identification of 92 regulatory Differentially Methylated Regions (DMR) localized in the promoter of DEGs. An in-depth study of the transcription factors binding sites (TFBS) in the DMRs corroborated the importance of TFBS's DNA methylation for gene expression in CCC myocardium. TBX21, RUNX3 and EBF1 are the transcription factors whose binding motif appears to be affected by DNA methylation in the largest number of genes. By combining both transcriptomic and methylomic analysis on heart tissue, and methylomic analysis on blood, 4 biological processes affected by severe CCC have been identified, including immune response, ion transport, cardiac muscle processes and nervous system. An additional study on blood methylation of moderate CCC samples put forward the importance of ion transport and nervous system in the development of the disease.
  • article 1 Citação(ões) na Scopus
    Long-Term Pulmonary Vascular Reactivity After Orthotopic Heart Transplantation by the Biatrial Versus the Bicaval Technique
    (2011) FIORELLI, A. I.; SANTOS, R. H. B.; OLIVEIRA JR., J. L.; SILVA, M. A. F. Da; SANTOS JR., V. P. dos; REGO, F. M. P.; SOUZA, G. E.; BACAL, F.; BOCCHI, E. A.; STOLF, N. A. G.
    Introduction. Advantages of the bicaval versus the biatrial technique have been reported, emphasizing atrial electrical stability and less tricuspid regurgitation. Objective. To analyze the impact of the surgical technique on long-term pulmonary pressures, contractility, and graft valvular behavior after heart transplantation. Methods. Among 400 orthotopic heart transplantation recipients from 1985 to 2010, we selected 30 consecutive patients who had survived beyond 3 years. The biatrial versus bicaval surgical technique groups included 15 patients each. Their preoperative clinical characteristics were similar. None of the patients displayed a pulmonary vascular resistance or pulmonary artery pressure over 6U Wood or 60 mm Hg, respectively. We evaluated invasive hemodynamic parameters during routine endomyocardial biopsies. Two-dimensional echocardiographic parameters were obtained from routine examinations. Results. There were no significant differences regarding right atrial pressure, systolic pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, cardiac index, systolic blood pressure, left ventricular ejection fraction, and mitral regurgitation (P > .05). Tricuspid regurgitation increased significantly over the 3 years of observation only among the biatrial group (P = .0212). In both groups, the right atrial pressure, pulmonary wedge capillary pressure, transpulmonary gradient, and pulmonary vascular resistance decreased significantly (P < .05) from the pre- to the postoperative examination. In both groups cardiac index and systemic blood pressure increased significantly after transplantation (P < .05). Comparative analysis of the groups only showed significant differences regarding right atrial pressure and degree of tricuspid regurgitation; the bicaval group showing the best performance. Conclusions. Both surgical techniques ensure adequate left ventricular function in the long term; however, the bicaval technique provided better trends in hemodynamic performance, as well as a lower incidence and severity of tricuspid valve dysfunction.
  • article 4 Citação(ões) na Scopus
    Successful Endomyocardial Biopsy Guided by Transthoracic Two-Dimensional Echocardiography
    (2011) FIORELLI, A. I.; COELHO, G. B.; SANTOS, R. H. B.; OLIVEIRA JR., J. L.; AIELO, V.; BENVENUTI, L.; OLIVEIRA, A. S.; SILVA, M. A. F. Da; CHIZZOLA, P. R.; COSTA, R.; MATHIAS JR., W.; BACAL, F.; BOCCHI, E. A.; STOLF, N. A. G.
    Introduction. Two-dimensional (2-D) echocardiography is an excellent alternative method to perform endomyocardial biopsies (EB) in special situations, mainly when the patient is in a critical state and cannot go to the catheterization laboratory or when there are contraindications to the use of fluoroscopy as in the pregnancy. Objective. This single-center experience analyzed the last 25 years use of an EB technique guided by echocardiography realized at the bedside on critical patients. Methods. From 1985 to 2010, we performed 76 EB guided by 2-D echocardiography on 59 patients, among whom 38 (64.4%) were critically ill with examinations at the bedside; among 10 (16.9%) subjects, the procedure was carried out simultaneously with fluoroscopy for safety's sake during the learning period. In addition, 8 (13.6%) were unavailable for fluoroscopy, and 3 (5.1%) required a hybrid method due to an intracardiac tumor. Results. The main adverse effects included local pain (n = 4, 5.6%); difficult out successful puncture due to previous biopsies (n = 4, 5.6%); local hematoma without major consequences (n = 3, 4.2%); failed but ultimately successful puncture on the first try due to previous biopsies or (n = 3, 4.2%); obesity and immediate postoperative period with impossibility to pass the bioptome into the right ventricle; however 2 days later the procedure was repeated successfully by echocardiography (n = 1, 1.4%). All myocardial specimens displayed suitable size. There were no undesirable extraction effects on the tricuspid valve tissue. In this series, there was no case of death, hemopericardium, or other major complication as a direct consequence of the biopsy. Conclusion. 2-D echocardiography is a special feature to guide EB is mainly in critically ill patients because it can be performed at the bedside without additional risk or disadvantages of fluoroscopy. The hybrid method associating 2-D echocardiography and fluoroscopy allows the procedure in different situations such as intracardiac tumor cases.