Biomedical subjects

Y Nagata

Publications and source records attributed to Y Nagata.

At least 91 records · Page 5Linked to original sources

PubMed2000

Induction of primary NY-ESO-1 immunity: CD8+ T lymphocyte and antibody responses in peptide-vaccinated patients with NY-ESO-1+ cancers.

Cancer-testis antigen NY-ESO-1 is one of the most immunogenic tumor antigens defined to date. Spontaneous humoral and CD8+ T-cell responses to NY-ESO-1 are detected in 40-50% of patients with advanced NY-ESO-1-expressing tumors. A clinical trial was initiated to study the immunological effects of intradermal vaccination with 3 HLA-A2-binding NY-ESO-1 peptides in 12 patients with metastatic NY-ESO-1-expressing cancers. Seven patients were NY-ESO-1 serum antibody negative, and five patients were NY-ESO-1 serum antibody positive at the outset of the study. Primary peptide-specific CD8+ T-cell reactions and delayed-type hypersensitivity responses were generated in four of seven NY-ESO-1 antibody-negative patients. Induction of a specific CD8+ T-cell response to NY-ESO-1 in immunized antibody-negative patients was associated with disease stabilization and objective regression of single metastases. NY-ESO-1 antibody-positive patients did not develop significant changes in baseline NY-ESO-1-specific T-cell reactivity. However, stabilization of disease and regression of individual metastases were observed in three of five immunized patients. These results demonstrate that primary NY-ESO-1-specific CD8+ T-cell responses can be induced by intradermal immunization with NY-ESO-1 peptides, and that immunization with NY-ESO-1 may have the potential to alter the natural course of NY-ESO-1-expressing tumors.

Amino Acid Sequence↗

PubMed2000

Determination of haloalkane dehalogenase activity by capillary zone electrophoresis.

A new sensitive method has been developed for the determination of haloalkane dehalogenase activity. The enzymatic reactions were carried out directly in thermostatted autosampler vials and the formation of product - bromide or chloride ions - was monitored by sequential capillary zone electrophoresis runs. The determinations were performed in a 75 microm fused-silica capillary using 5 mM chromate, 0.5 mM tetradecyltrimethylammonium bromide (pH 8.4) as a background electrolyte, separation voltage 15 kV (negative polarity) and indirect detection at sample wavelength 315 nm, reference wavelength 375 nm for brominated and chlorinated substrates, respectively 0.1 M beta-alanine-HCl (pH 3.50) as a background electrolyte, separation voltage 18 kV (negative polarity) and direct detection at 200 nm for brominated substrates. The temperature of capillary was in both cases 25 degrees C. The method is rapid, can be automated, and requires only small amount of enzyme preparation and substrate.

Electrophoresis, Capillary↗

PubMed2000

Expression of the bph genes involved in biphenyl/PCB degradation in Pseudomonas sp. KKS102 induced by the biphenyl degradation intermediate, 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid.

The bph genes involved in PCB/biphenyl degradation in Pseudomonas sp. KKS102 are clustered as bphEGFA1A2A3BCDA4R. The bph genes are inducibly expressed in the presence of biphenyl. In order to understand the induction more fully, the inducer of bph gene expression was investigated. To identify the inducer molecule, we constructed four deletion mutants of the structural genes and analyzed the inducibility of the bphE gene in each mutant strain. In the wild-type cell and the bphD deletion mutant, the levels of the bphE transcript were enhanced in the presence of biphenyl. On the other hand, in the bphA, bphB, and bphC deletion mutants, levels of the bphE transcript were not enhanced in the presence of biphenyl. These results demonstrated that the series of reactions catalyzed by biphenyl dioxygenase (BphA), dihydrodiol dehydrogenase (BphB), and 2, 3-dihydroxybiphenyl dioxygenase (BphC) are necessary to convert biphenyl to the inducer. It is known that these reactions convert biphenyl to 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA), and it was found that the expression of the bph genes was induced by purified HOPDA. These results clearly indicate that HOPDA is the inducer of the bph genes in KKS102.

Biodegradation, Environmental↗

PubMed2000

Strategy for monitoring T cell responses to NY-ESO-1 in patients with any HLA class I allele.

NY-ESO-1 elicits frequent antibody responses in cancer patients, accompanied by strong CD8(+) T cell responses against HLA-A2-restricted epitopes. To broaden the range of cancer patients who can be assessed for immunity to NY-ESO-1, a general method was devised to detect T cell reactivity independent of prior characterization of epitopes. A recombinant adenoviral vector encoding the full cDNA sequence of NY-ESO-1 was used to transduce CD8-depleted peripheral blood lymphocytes as antigen-presenting cells. These modified antigen-presenting cells were then used to restimulate memory effector cells against NY-ESO-1 from the peripheral blood of cancer patients. Specific CD8(+) T cells thus sensitized were assayed on autologous B cell targets infected with a recombinant vaccinia virus encoding NY-ESO-1. Strong polyclonal responses were observed against NY-ESO-1 in antibody-positive patients, regardless of their HLA profile. Because the vectors do not cross-react immunologically, only responses to NY-ESO-1 were detected. The approach described here allows monitoring of CD8(+) T cell responses to NY-ESO-1 in the context of various HLA alleles and has led to the definition of NY-ESO-1 peptides presented by HLA-Cw3 and HLA-Cw6 molecules.

Alleles↗

PubMed2000

Clostridial gas gangrene. I. Cellular and molecular mechanisms of microvascular dysfunction induced by exotoxins of Clostridium perfringens.

Mechanisms responsible for the rapid tissue destruction in gas gangrene are not well understood. To examine the early effects of Clostridium perfringens exotoxins on tissue perfusion, a rat model of muscle blood flow was developed. Intramuscular injection of a clostridial toxin preparation containing both phospholipase C (PLC) and theta-toxin caused a rapid (1-2 min) and irreversible decrease in blood flow that paralleled formation of activated platelet aggregates in venules and arterioles. Later (20-40 min), aggregates contained fibrin and leukocytes, and neutrophils accumulated along vascular walls. Flow cytometry confirmed that these clostridial toxins or recombinant PLC induced formation of P-selectin-positive platelet aggregates. Neutralization of PLC activity in the clostridial toxin preparation completely abrogated human platelet responses and reduced perfusion deficits. It is concluded that tissue destruction in gas gangrene is related to profound attenuation of blood flow initiated by activation of platelet responses by PLC.

Animals↗

PubMed2000

Clostridial gas gangrene. II. Phospholipase C-induced activation of platelet gpIIbIIIa mediates vascular occlusion and myonecrosis in Clostridium perfringens gas gangrene.

Clostridium perfringens gas gangrene is a fulminant infection, and radical amputation remains the single best treatment. It has been hypothesized that rapid tissue destruction is related to tissue hypoxia secondary to toxin-induced vascular obstruction, and previous studies demonstrated that phospholipase C (PLC) caused a rapid and irreversible decrease in skeletal muscle blood flow that paralleled the formation of intravascular aggregates of activated platelets, fibrin, and leukocytes. In this study, flow cytometry demonstrated that PLC stimulated platelet/neutrophil aggregation in a gpIIbIIIa-dependent fashion. Pretreatment of animals with heparin or depletion of leukocytes reduced blood-flow deficits, and aggregate formation caused by PLC. It is concluded that fulminant tissue destruction in gas gangrene results from profound attenuation of blood flow caused by PLC-induced, gpIIbIIIa-mediated formation of heterotypic platelet/polymorphonuclear leukocyte aggregates. Therapeutic strategies that target gpIIbIIIa may prevent vascular occlusion, maintain tissue viability, and provide an alternative to radical amputation for patients with this infection.

Animals↗

PubMed2000

A HER2/NEU-derived peptide, a K(d)-restricted murine tumor rejection antigen, induces HER2-specific HLA-A2402-restricted CD8(+) cytotoxic T lymphocytes.

We have identified an H-2K(d)-binding peptide, HER2p780 (PYVSRLLGI), derived from murine HER2/neu (HER2), that can induce HER2-specific murine cytotoxic T lymphocytes (CTL). Weekly vaccination of BALB/c mice by syngeneic dendritic cells pulsed with HER2p780 peptide, entirely common to murine and human HER2, suppressed growth of pretransplanted HER2-expressing syngeneic tumors. A HER2-expressing human cancer cell line SKOV3 transfected with murine H-2K(d) cDNA could also be lysed by HER2p780-specific murine CTLs, indicating that human HER2-expressing cancer cells can process and present the cognate peptide in the context of H-2K(d). Since H-2K(d) and HLA-A2402 molecules have similar anchor motifs, the possibility of inducing HER2-specific CTL activity with HER2p780 in HLA-A2402 individuals was examined. CD8(+) CTL clones specific for HER2-expressing cancer cell lines were established from peripheral blood lymphocytes with HLA-A2402 by repeatedly sensitizing with peptide-pulsed autologous dendritic cells as well as peripheral blood mononuclear cells. Detailed analysis of their specificity revealed that the cytotoxicity of CTL clones is specific for the cognate peptide with HLA-A2402 restriction. The results suggest that HER2p780 is a unique peptide that may function as a tumor rejection antigen peptide in HLA-A2402 individuals, as it was directly proven here to function in a murine tumor system.

Animals↗

PubMed2000

Head-and-neck stages I and II extranodal non-Hodgkin's lymphomas: real classification and selection for treatment modality.

PURPOSE: We re-evaluated histopathological specimens of head and neck early-stage extranodal non-Hodgkin's lymphoma (NHL) using the revised European and American lymphoma (REAL) classification, and also investigated the relationship between the clinical characteristics and histopathological classification in an attempt to evaluate the usefulness of this new classification system in selecting treatment modalities. MATERIALS AND METHODS: Between 1979 and 1995, 117 patients with histologically confirmed stages I and II NHL of head-and-neck extranodal regions were treated. Of these patients, 110 specimens were available for re-evaluation. Sixty-four patients had Stage I, and 46 had Stage II diseases. All but 3 had received radiation therapy, and 59 patients were also treated with intensive combination chemotherapy. RESULTS: There were 32 extranodal marginal-zone B-cell lymphomas, 57 diffuse large B-cell lymphomas, 11 peripheral T/NK-cell lymphomas, and 10 others. The 5- and 10-year cause-specific survival rates for all patients were 72% and 62%, respectively. Patients with extranodal marginal-zone B-cell lymphoma or other low-grade B-cell lymphomas demonstrated higher survival rates than patients with other lymphomas. Patients with peripheral T/NK lymphomas showed the lowest survival rate. CONCLUSION: The REAL classification accurately indicated the prognosis of patients with NHL. These results suggest that appropriate treatment modalities can be selected using this classification.

Adolescent↗

PubMed2000

Identification of NY-ESO-1 peptide analogues capable of improved stimulation of tumor-reactive CTL.

Expression of NY-ESO-1 in a high proportion of different human tumors makes this protein a very attractive vaccine target. NY-ESO-1 peptides, recognized by HLA-A2-restricted CTL, have recently been described. However, it remains unclear how efficiently tumors generate these epitopes, and whether peptide analogues can be used for optimal expansion and activation of NY-ESO-1-specific HLA-A2-restricted CTL. By generating unique CTL clones, we demonstrate that NY-ESO-1-positive tumor cells are efficiently killed by HLA-A2-restricted CTL specific for the peptide epitope NY-ESO-1 157-165. Presentation of this epitope is not affected by the presence or absence of the proteasome subunits low molecular proteins 2 and 7 and is not blocked by proteasome inhibitors, while it is impaired in the TAP-deficient cell line LBL 721.174. NY-ESO-1 157-165 peptide analogues were compared for their antigenicity and immunogenicity using PBL from melanoma patients. Three peptides, containing the carboxyl-terminal cysteine substituted for either valine, isoleucine, or leucine, were recognized at least 100 times more efficiently than the wild-type peptide by specific CTL. Peptide analogues were capable of stimulating the expansion of NY-ESO-1-specific CTL from PBL of melanoma patients much more efficiently than wild-type peptide. These findings define the processing requirements for the generation of the NY-ESO-1 157-165 epitope. Identification of highly antigenic NY-ESO-1 peptide analogues may be important for the development of vaccines capable of expanding NY-ESO-1-specific CTL in cancer patients.

Amino Acid Substitution↗

PubMed2000

The effects of physical exercise on body fat distribution and bone mineral density in postmenopausal women.

OBJECTIVE: The present cross-sectional study investigated the effects of physical exercise on body fat distribution and bone mineral density (BMD). METHODS: Subjects were 57 postmenopausal women (mean age, 60.5+/-6.4 years) who had exercised regularly for at least 2 years. Controls were 130 age-matched sedentary women. Age, years since menopause (YSM), height, weight, and body mass index (BMI, wt./ht.(2)) were recorded. Total fat mass, percentage of body fat, trunk fat mass, leg fat mass, the ratio of trunk fat mass to leg fat mass (trunk-leg fat ratio), total body lean mass, percentage of body lean, and lumbar spine BMD (L2-L4) were measured by dual-energy X-ray absorptiometry. RESULTS: Baseline characteristics and leg fat mass did not differ between the two groups. Total fat mass, percentage of body fat, trunk fat mass, and trunk-leg fat ratio were lower (P<0.05, P<0.01, P<0.01 and P<0.001, respectively), while total body lean mass, percentage of body lean mass, and lumbar spine BMD were higher in exercising women (P<0.05, P<0.05 and P<0.01, respectively). Performing physical exercise was inversely correlated with trunk-leg fat ratio (standardized regression coefficient=-0.178, P<0.01), but positively correlated with BMD (0. 203, P<0.01) irrespective of age, height, YSM, and total fat mass. CONCLUSION: Physical exercise has beneficial effects on body fat distribution and BMD in postmenopausal women. Reduction of upper body fat distribution with physical exercise may be more attributable to the decrease in trunk fat mass.

Absorptiometry, Photon↗

PubMed2000

Monitoring CD8 T cell responses to NY-ESO-1: correlation of humoral and cellular immune responses.

NY-ESO-1, a member of the cancer-testis family of antigens, is expressed in a subset of a broad range of different human tumor types. Patients with advanced NY-ESO-1-expressing tumors frequently develop humoral immunity to NY-ESO-1, and three HLA A2-restricted peptides were defined previously as targets for cytotoxic CD8(+) T cells in a melanoma patient with NY-ESO-1 antibody. The objectives of the present study were (i) to develop enzyme-linked immunospot (ELISPOT) and tetramer assays to measure CD8(+) T cell responses to NY-ESO-1, (ii) to determine the frequency of CD8(+) T cell responses to NY-ESO-1 in a series of HLA-A2 patients with NY-ESO-1 expressing tumors, (iii) to determine the relation between CD8(+) T cell and humoral immune responses to NY-ESO-1, and (iv) to compare results of NY-ESO-1 ELISPOT assays performed independently in two laboratories with T cells from the same patients. NY-ESO-1 ELISPOT and tetramer assays with excellent sensitivity, specificity, and reproducibility have been developed and found to correlate with cytotoxicity assays. CD8(+) T cell responses to HLA-A2-restricted NY-ESO-1 peptides were detected in 10 of 11 patients with NY-ESO-1 antibody, but not in patients lacking antibody or in patients with NY-ESO-1-negative tumors. The results of ELISPOT assays were concordant in the two laboratories, providing the basis for standardized monitoring of T cell responses in patients receiving NY-ESO-1 vaccines.

Antibody Formation↗

PubMed2000

Difference in the effect of adiposity on bone density between pre- and postmenopausal women.

OBJECTIVES: Elevated bone mineral density (BMD) in obese women is partially attributable to the higher circulating estrogen levels derived from extraglandular aromatization in adipose tissue. However, it remains unclear whether there is an effect of overall adiposity on BMD in both pre- and postmenopausal women. The difference in the effect of overall adiposity on BMD between pre- and postmenopausal women was investigated. MATERIALS AND METHODS: Subjects were 296 premenopausal women with regular menstruation and 233 postmenopausal women. Age, age at menarche, years since menopause (YSM, in postmenopausal women), weight, height, and body mass index were recorded. Total fat mass amount, lean mass amount, and percentage of body fat were measured by whole body scanning with dual-energy X-ray absorptiometry (DEXA). Lumbar spine BMD (L2-L4) was measured by DEXA. In each group, significant determinants of BMD were investigated using univariate and stepwise multiple regression analysis. RESULTS: In postmenopausal women, YSM, lean mass amount, total fat mass amount, and height were significant determinants of BMD (R(2)=0.273, P<0.001). In premenopausal women, only two variables including lean mass amount and age at menarche were significant determinants of lumbar spine BMD (R(2)=0.110, P<0.001), but total fat mass amount and percentage of body fat were not significant determinants of BMD. CONCLUSION: The effect of overall adiposity on BMD is more prominent in postmenopausal women than in premenopausal women.

Absorptiometry, Photon↗

PubMed2000

Identification of NY-ESO-1 epitopes presented by human histocompatibility antigen (HLA)-DRB4*0101-0103 and recognized by CD4(+) T lymphocytes of patients with NY-ESO-1-expressing melanoma.

NY-ESO-1 is a member of the cancer-testis family of tumor antigens that elicits strong humoral and cellular immune responses in patients with NY-ESO-1-expressing cancers. Since CD4(+) T lymphocytes play a critical role in generating antigen-specific cytotoxic T lymphocyte and antibody responses, we searched for NY-ESO-1 epitopes presented by histocompatibility leukocyte antigen (HLA) class II molecules. Autologous monocyte-derived dendritic cells of cancer patients were incubated with recombinant NY-ESO-1 protein and used in enzyme-linked immunospot (ELISPOT) assays to detect NY-ESO-1-specific CD4(+) T lymphocyte responses. To identify possible epitopes presented by distinct HLA class II alleles, overlapping 18-mer peptides derived from NY-ESO-1 were synthetized and tested for recognition by CD4(+) T lymphocytes in autologous settings. We identified three NY-ESO-1-derived peptides presented by DRB4*0101-0103 and recognized by CD4(+) T lymphocytes of two melanoma patients sharing these HLA class II alleles. Specificity of recognition was confirmed by proliferation assays. The characterization of HLA class II-restricted epitopes will be useful for the assessment of spontaneous and vaccine-induced immune responses of cancer patients against defined tumor antigens. Further, the therapeutic efficacy of active immunization using antigenic HLA class I-restricted peptides may be improved by adding HLA class II-presented epitopes.

Alleles↗

PubMed2000

The oocyte-specific methylated region of the U2afbp-rs/U2af1-rs1 gene is dispensable for its imprinted methylation.

Imprinted genes harbor discrete regions which are differentially methylated in gametes; usually the final differential methylation patterns in adults are established during embryogenesis through modifications of the initial methylation patterns in gametes. Previous reports have shown that a 200-bp region termed region II within the CpG island of the mouse imprinted U2afbp-rs gene is methylated in oocytes but not in sperm, suggesting that this region is a center for the propagation of methylated CpGs on the maternal allele and is also a candidate for an imprinting control element. To determine whether region II is required for the imprinted methylation of this gene at the endogenous locus, we generated mice carrying a deletion of this region. We herein show that parental methylation differences still exist in the CpG island on the region II-deleted allele. These findings suggest that region II is dispensable for the imprinted methylation of the U2afbp-rs gene.

Animals↗

PubMed2000

A novel human HER2-derived peptide homologous to the mouse K(d)-restricted tumor rejection antigen can induce HLA-A24-restricted cytotoxic T lymphocytes in ovarian cancer patients and healthy individuals.

A mouse HER2-derived peptide, HER2p63 (A) (TYLPANASL), can induce K(d)-restricted mouse cytotoxic T lymphocytes (CTL) and also function as a tumor rejection antigen in an in vivo assay. Since the anchor motif of mouse K(d) for peptide binding has much similarity to that of human HLA-A2402, we asked if human HER2p63 (T) (TYLPTNASL) could induce HER2-specific CTL in HLA-A2402-positive individuals. Peripheral blood mononuclear cells (PBMC) of HLA-A2402-positive individuals were sensitized in vitro with HER2p63-pulsed autologous dendritic cells prepared from PBMC. CTL clone derived from these specifically lysed HER2-expressing cell lines bearing HLA-A2402. Cytotoxic activity of the CTL clone against the HER2-expressing cell line bearing HLA-A2402 was blocked by antibodies against CD3, CD8, HLA-A24 or MHC class I, and was also inhibited by the addition of excess HER2p63-pulsed C1R bearing HLA-A2402. Killer cells were generated from PBMC of seven healthy individuals and five ovarian cancer patients, all of HLA-A2402 type, by in vitro sensitization with HER2p63-pulsed autologous antigen presenting cells. These killer cells selectively lysed HER2-expressing SKOV3 transfected with HLA-A2402 cDNA, indicating high immunogenicity of HER2p63 in all 12 individuals examined.

Animals↗

PubMed2000

Cosmetic results and complications after breast conserving therapy for early breast cancer.

BACKGROUND: The cosmetic and functional results of breast conserving therapy for early breast cancer were evaluated. These are important endpoints in the assessment of breast conserving therapy in addition to tumor control and survival. The factors suspected to influence cosmesis were also analyzed. METHODS: In 206 patients with stage I and II breast cancer treated by wide excision and axillary dissection followed by radiation therapy, the cosmetic results and complications were analyzed. The cosmetic outcome was assessed by a scoring method and breast retraction assessment (BRA). As complications, arm edema and restriction of shoulder movement and late skin reactions were analyzed. RESULTS: Of the 206 patients 92% showed an excellent to good cosmetic score before radiation therapy. The score deteriorated, but gradually improved and stabilized after 1 year. Eighty-one percent of the patients had an excellent to good cosmetic score at 3 years. The BRA of the 206 patients was 1.8 cm on average before radiation therapy. It increased to 2.3 cm after termination of radiation therapy, and did not change thereafter. Tumor size over 2 cm (p = 0.005) and tumors in the inner quadrant (p = 0.003) were factors which negatively affected the cosmetic score at 3 years. Tumor size over 2 cm (p = 0.003), tumors in the upper quadrant (p = 0.005), or a nipple-tumor distance of more than 2 cm (p = 0.01) were also negative factors for the BRA at 3 years. Arm edema, restriction of shoulder movement, and late skin reaction were generally mild, and were observed in 12%, 0% and 34% of patients at 3 years, respectively. CONCLUSIONS: The overall cosmetic results of breast conserving therapy are acceptable and the complication rate is low. Tumor characteristics, tumor size, location and nipple-tumor distance are factors that affect cosmesis.

Adult↗

PubMed2000

Determination of optimal radiation energy for different breast sizes using CT-simulator [correction of simulatior] in tangential breast irradiation.

BACKGROUND: The purpose of this study is to determine and recommend the optimal radiation source according to breast size for tangential irradiation in breast conserving therapy. METHODS: Twenty-eight patients treated at our department from January 1994 to January 1996 were studied. The dose distribution within the irradiated breast was calculated using a (60)Co-gamma ray and 6 MV-X ray. Then we compared 3-D dose distributions of the (60)Co-gamma ray and 6 MV-X ray in different-sized breasts. Three parameters (breast volume, chest wall separation, and breast height) were adopted as representative of breast size. We also examined correlations among the three parameters. RESULTS: When the breast size was large (breast volume >400 cm(3), chest wall separation > 19.5 cm, or breast height > 6.5 cm), the average volume of normal tissue which received more than 110% of the isocenter dose ("hot spot") was significantly greater with the (60)Co-gamma ray than with the 6 MV-X ray (p < 0.05). A similar result was obtained with regard to hot spots in the clinical target volume. The cold area that received less than 95% of the isocenter dose was greater using a 6 MV-X ray when the breast size was small (breast volume <200 cm(3), chest wall separation <17.5 cm, or breast height <5.0 cm). However, the difference was not significant. There was a significant correlation between breast volume and chest wall separation (r =0.849, p <0.001). Breast volume and breast height were also significantly correlated (r =0.813, p <0.001). CONCLUSIONS: Since breast volume and shape are different in each patient, the optimal energy should be selected for each case to obtain uniform dose distribution in breast-conserving therapy. Chest wall separation or breast height, which are measurable without a 3-D planning system, can substitute for breast volume as parameters for breast size. We recommend that the (60)Co-gamma ray not be used for treating large breasts, those with chest wall separation > or =19.5 cm or breast height > or =6.5 cm.

Anthropometry↗

PubMed2000

Tamponade after open-heart surgery with percutaneous cardiopulmonary support.

A 56-year-old man presented with late cardiac tamponade appearing on 9 postoperative day after weaning from percutaneous cardiopulmonary support. He had been referred to our hospital for congestive heart failure. He underwent aortic valve replacement and fell into postcardiotomy low output syndrome. He could not be weaned from extracorporeal circulation, and we had to use an intraaortic balloon pump and percutaneous cardiopulmonary support. On postoperative day 9, percutaneous cardiopulmonary support was successfully withdrawn without problems, but he showed signs of superior vena cava syndrome after the cannulas were removed. An echocardiogram also showed cardiac tamponade. When the wound was reopened, a lot of old clots had compressed the right atrium and, after clot removal, the patient's hemodynamic state improved markedly. It is important to be aware that percutaneous cardiopulmonary support may conceal hemodynamic deterioration due to cardiac tamponade and to take care that a patient does not experience hemodynamic deterioration after percutaneous cardiopulmonary support withdrawal.

Cardiac Output, Low↗