1
|
Quan SD, Morra D, Lau FY, Coke W, Wong BM, Wu RC, Rossos PG. Perceptions of urgency: defining the gap between what physicians and nurses perceive to be an urgent issue. Int J Med Inform 2012; 82:378-86. [PMID: 23245809 DOI: 10.1016/j.ijmedinf.2012.11.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Revised: 10/02/2012] [Accepted: 11/16/2012] [Indexed: 10/27/2022]
Abstract
INTRODUCTION Through our research into the design and evaluation of technology systems to improve the quality and safety of clinical communication, we have discovered that physicians and nurses differ in perspective regarding clinical prioritization and desirable response times. This has a number of important consequences including unnecessary interruptions, escalating conflict and deterioration in interprofessional relationships. Understanding the differing perspectives on clinical prioritization, or the gap in perceived urgency, may improve interprofessional relationships. METHODS We conducted a mixed-methods study utilizing both qualitative (semi-structured interviews) and quantitative (surveys) methods to determine the gap between perceived urgency among physicians and nurses. The survey comprised of real messages extracted from the clinical communication system that was implemented. Physicians and nurses reviewed the messages and assigned an urgency level to each. The semi-structured interviews used open-ended questions to act as a guide to highlight key themes of interest. Thematic analysis, frequency tabulation, and triangulation were used to analyze the data. RESULTS Although the surveys demonstrated concordance between physicians and nurses when independently ranking the urgency of clinical messages (kappa=0.66 SE 0.15), agreement was only fair in comparison to the urgency identified by the original nurse who sent the message (kappa=0.22 SE 0.18). We hypothesize that clinical context has a major role in defining urgency and may explain this finding. The survey data was triangulated with the semi-structured interview data and it was determined that the desired response time significantly impacted the sender's message prioritization. For example, shift changes and anxious family members were associated with discordant prioritizations. DISCUSSION This study demonstrated that the perceived communication urgency gap between sending nurses and receiving physicians was primarily related to timeframe and context, not clinical condition. Most disagreement occurred when nurses used urgent messaging for time sensitive but not clinically urgent issues in an effort to expedite the resolution of their issue by the physicians. These results indicate the need for clinical communication systems to incorporate decision support around both clinical prioritization and expected response time in their design. Effective interprofessional communication is essential to the provision of safe, quality-based healthcare; these results highlight some of the sociotechnical aspects of health information technology implementation that must be considered.
Collapse
Affiliation(s)
- S D Quan
- Centre for Innovation in Complex Care, University Health Network, Toronto, Canada.
| | | | | | | | | | | | | |
Collapse
|
2
|
|
3
|
Cheng Y, Wong R, Lam J, Lau FY, Cheng G. Estimated risk of deep venous thrombosis among Chinese patients admitted to general medical wards. J Thromb Haemost 2004; 2:1666-8. [PMID: 15333047 DOI: 10.1111/j.1538-7836.2004.00880.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
4
|
Chow LMC, Tang JCO, Teo ITN, Chui CH, Lau FY, Leung TWT, Cheng G, Wong RSM, Wong ILK, Tsang KMS, Tan WQ, Zhao YZ, Lai KB, Lam WH, Guo DA, Chan ASC. Antiproliferative activity of the extract of Gleditsia sinensis fruit on human solid tumour cell lines. Chemotherapy 2004; 48:303-8. [PMID: 12673105 DOI: 10.1159/000069713] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND The fruit extract of Gleditsia sinensis Lam. (GSE) is a traditional herbal medicine that is saponin-rich. However, its activity on solid tumour cell lines has never been demonstrated. METHODS The activity of GSE was demonstrated in four cancer cell lines (breast cancer MCF-7, MDA-MB231, hepatoblastoma HepG2 and oesophageal squamous carcinoma cell line SLMT-1) using MTT assay, anchorage-independent clonogenicity assay, DNA laddering and in situ cell death detection. RESULTS The mean MTT(50) (the mean concentration of GSE to reduce MTT activity by 50%) ranged from 16 to 20 microg/ml of GSE. An anchorage-independent clonogenicity assay showed that all of the four solid tumour cell lines gradually lost their regeneration potential after treatment with GSE, DNA fragmentation and TUNEL analysis demonstrated that the action of GSE is both dose- and time course-dependent. CONCLUSIONS Our results suggest that GSE has a cytotoxic activity and can induce apoptosis in human solid tumour cell lines.
Collapse
Affiliation(s)
- L M C Chow
- Department of Applied Biology and Chemical Technology and Central Laboratory of the Institute of Molecular Technology for Drug Discovery and Synthesis, Hong Kong Polytechnic University, China.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Abstract
BACKGROUND Fatal hemolytic transfusion reaction due to ABO incompatibility occurs mainly as a result of clerical errors. Blood sample drawn from the wrong patient and labeled as another patient's specimen will not be detected by the blood bank unless there is a previous ABO grouping result. METHODS In Hong Kong, we had designed a transfusion wristband system--portable barcode scanner system to detect such clerical errors. The system was well accepted by the house staff and had prevented two BO mismatched transfusion. Other current system of patient's identification may have similar results, but the wristband system has the advantages of being simple, inexpensive and easy to implement. The Hong Kong Government is planning to replace the personal identity card for all citizens with an electronic smart card by 2003. If the new card contains the person's detailed red cell phenotypes in digital code, then the phenotypes of all blood donors and admitted patients will be readily available. It is feasible to issue phenotype-matched blood to patients without any need of pre-transfusion testing, therefore eliminating mismatched transfusions for most patients. RESULTS Our pilot study of 474 patients showed that the system was safe and up to 98% of admitted patients could be transfused without delays. CONCLUSIONS Patients with rare phenotypes, visitors or illegal immigrants may still need pre-transfusion antibody screen, but if most patients can be issued blood units without testings, the potential savings in health care amount to US$14 million/year.
Collapse
Affiliation(s)
- F Y Lau
- Department of Medicine and Therapeutics, Prince of Wales Hospital, 9/F Clinical Sciences Building, Ng Shing Street, Shatin, N.T., Hong Kong, China
| | | |
Collapse
|
6
|
Chui CH, Lau FY, Wong R, Soo OY, Lam CK, Lee PW, Leung HK, So CK, Tsoi WC, Tang N, Lam WK, Cheng G. Vitamin B12 deficiency--need for a new guideline. Nutrition 2001; 17:917-20. [PMID: 11744340 DOI: 10.1016/s0899-9007(01)00666-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVES Many patients with vitamin B12 deficiency do not have anemia or macrocytosis, but the prevalence of B12 deficiency in patients without macrocytosis is not known. METHODS We investigated the prevalence of B12 deficiency among patients with normocytosis and microcytosis and recommended a screening strategy. All patients (n = 3714) with serum B12 measured at the Prince of Wales Hospital in 1996 were reviewed. The prevalence of serum B12 less than 140 pmol/L was determined for the following patient subgroups: younger than 70 y, older than 70 y, anemic, non-anemic, macrocytic, normocytic, microcytic, documented iron deficiency, and documented thalassemia. RESULTS The prevalence of B12 deficiency (<140 pmol/L) ranged from 4.8% to 9.8% among the different subgroups. CONCLUSIONS Whatever screening criteria were used, a significant number of B12-deficient patients will be missed. Therefore, there may be a case for universal vitamin B12 screening.
Collapse
Affiliation(s)
- C H Chui
- Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, People's Republic of China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Lau FY, Wong R, Chan NP, Chui CH, Ng E, Ng MH, Cheng G. Provision of phenotype-matched blood units: no need for pre-transfusion antibody screening. Haematologica 2001; 86:742-8. [PMID: 11454530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
BACKGROUND AND OBJECTIVES The Hong Kong government is planning to introduce an electronic smart identity card for all seven million citizens in 2003. If the smart card contains the full red cell phenotype/genotype of the individual, it may be possible to transfuse phenotype-matched blood units without pre-transfusion antibody screening. We conducted a feasibility study. DESIGN AND METHODS Red cell phenotype was determined for 407 donor blood units and 493 patients for whom an antibody screen had been ordered. The computer program selected phenotype-matched blood from the donor stock for the patients according to actual transfusion request. For patients with a positive antibody screen, full crossmatching was carried out with the computer-selected phenotype units. The frequencies of the various red cell phenotypes in the population were calculated from Red Cross data of antigen frequencies. The probabilities of finding at least one unit of phenotype-matched blood from a 300-unit hospital stock and a 4,000-unit Red Cross stock were determined for each phenotype. Cost analysis was performed. RESULTS Ninety-two out of 493 patients received a total of 395 blood units. The required number of phenotype-matched blood units could be found for 92 patients using a 300-unit pool and for all patients using a 4,000-unit pool. We calculated that phenotype-matched blood could be provided for more than 98% of patients without antibody screening. The total cost of the project is US$ 98 million with potential savings of US$ 14 million per year. INTERPRETATION AND CONCLUSIONS It is feasible and cost-effective to transfuse patients with phenotype-matched blood without antibody screening using a smart card system.
Collapse
Affiliation(s)
- F Y Lau
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong
| | | | | | | | | | | | | |
Collapse
|
8
|
Wong RS, Lau FY, Cheng G. Successful treatment of acquired hypoprothrombinemia without associated lupus anticoagulant using intravenous immunoglobulin. Haematologica 2001; 86:551. [PMID: 11410426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
|
9
|
Lau FY, Wong R, Chui CH, Cheng G. Successful Engraftment in Two Adult Patients with Severe Aplastic Anemia Using Nonmyeloablative Conditioning Followed by Unrelated HLA-Mismatched Cord Blood Transplantation. ACTA ACUST UNITED AC 2001; 10:309-11. [PMID: 11359678 DOI: 10.1089/15258160151135060] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Umbilical cord blood as an alternative source of hematopoietic stem cells and nonmyeloablative conditioning are very exciting new developments in transplantation. We report here mixed chimerism in two adult patients with severe aplastic anaemia using nonmyeloablative conditioning and two-antigen mismatched cord blood transplantation resulting in satisfactory clinical response. Our results suggest that such transplant is possible with minimal toxicity.
Collapse
Affiliation(s)
- F Y Lau
- Department of Medicine and Therapeutics, Prince of Wales Hospital, Shatin, NT Hong Kong
| | | | | | | |
Collapse
|
10
|
Wong R, Lau FY, Chui CH, Tsang KS, Chik KW, Li CK, Cheng G. Transfusion of peripheral blood stem cells from donor homozygous for a shared HLA-haplotype: avoiding fatal transfusion-associated graft-versus-host disease while preserving anti-leukemic effect. Transplantation 2001; 71:487-90. [PMID: 11233917 DOI: 10.1097/00007890-200102150-00027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Fatal transfusion-associated graft-versus-host disease was observed in immunocompetent patients transfused with blood from donors homozygous for a shared haplotype with the recipient (the P-F1 barrier). We tested whether it was possible to carry out successful transplantation in a patient with relapsed acute myeloid leukemia, using peripheral blood stem cells from his HLA-homozygous brother (HLA A2, B46, DRB1 901) who shared a haplotype with the patient (HLA A2, B46,75, DRB1 901,12). METHODS A CD34 positively selected cell fraction (5.46x 10(6) CD34 cells/kg) was infused first, followed by subsequent infusion of graded doses of donor T cells (total 7.25x10(7) T cells/kg). Nonmyeloablative chemotherapy with idarubicin and cytarabine was given during the transplantation to reduce the leukemic burden and facilitate engraftment. Polymerase chain reaction with the VNTR primers, D1S80, was used to detect engraftment. RESULTS Complete remission (>300days) and successful donor engraftment (90%) were achieved. CONCLUSIONS Peripheral blood stem cells transplantation from a donor with a homozygous shared haplotype is possible with a minimal preparative regimen.
Collapse
Affiliation(s)
- R Wong
- Department of Medicine & Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital
| | | | | | | | | | | | | |
Collapse
|
11
|
Abstract
Fatal haemolytic transfusion reaction due to ABO incompatibility occurs mainly as a result of clerical error. A blood sample drawn from the wrong patient and labelled as another patient's will not be detected by the blood bank unless there is a previous ABO grouping result. We report here the detection of such clerical error by the use of a specially designed transfusion wristband. The wristband has the following special features: (i) once attached, it cannot be removed except by cutting; (ii) it has a pocket containing a transfusion label; (iii) a unique transfusion barcode is printed on each transfusion label and the corresponding wristband simultaneously by computer technology; (iv) a transfusion label removed from the wristband after attachment to the patient has a characteristic tear-mark distinguishing it from one removed prior to attachment. The blood bank only accepted those specimens bearing the tear-marked transfusion labels. All blood units for this patient were labelled with this unique transfusion code together with the patient's details. The nurses counter-checked the transfusion code on the blood units against the transfusion code on the patient's transfusion wristband prior to transfusion. If the blood sample for compatibility testing was drawn from the 'wrong' patient, the intended patient either did not carry a wristband or the transfusion codes did not match at all. Pretransfusion compatibility tests were performed on 2189 patient samples using this procedure. It was well accepted by both ward and blood bank staff. Two potential mismatched transfusions were avoided. These two clerical errors would not have been detected because neither patient had previous ABO grouping results.
Collapse
Affiliation(s)
- F Y Lau
- Department of Medicine and Therapeutics, Chinese University of Hong Kong, China
| | | | | | | | | |
Collapse
|
12
|
Leung TW, Cheng G, Chui CH, Ho SK, Lau FY, Tjong JK, Poon TC, Tang JC, Tse WC, Cheng KF, Kong YC. Yuehchukene, a bis-indole alkaloid, and cyclophosphamide are active in breast cancer in vitro. Chemotherapy 2000; 46:62-8. [PMID: 10601799 DOI: 10.1159/000007257] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Yuehchukene (YCK) is a novel bis-indole alkaloid with weak estrogenic activity. Biochemical studies showed that YCK could attenuate estrogenic action. In this study, the response of MCF-7, an estrogen-receptor-positive breast cancer cell line, under different combinations of estradiol, cyclophosphamide and YCK, was tested. From the dose-response curve, we discovered that 10(-2) M cyclophosphamide, even in its so-called 'bio-inert' form, could inhibit MCF-7 cell growth. However, the cytotoxic effect of cyclophosphamide was lost by reducing its concentration to approximately 1 x 10(-3) M. On the other hand, a low concentration ( approximately 10(-8)-10(-9) M) of YCK was found to potentiate the cytotoxic effect of cyclophosphamide on the MCF-7 cell line. Such an effect was absent in the estrogen-receptor-negative cell line MDA-MB-231. These findings, together with the dual role of a mixed estrogen and anti-estrogen effect, suggested that YCK and cyclophosphamide can be a potential combination in chemo-hormonal therapy for breast cancer.
Collapse
Affiliation(s)
- T W Leung
- Department of Clinical Oncology, Sir Yue-Kong Pao Cancer Centre, The Chinese University of Hong Kong, Hong Kong.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Lau FY. String-plucking as a mechanism of chordal rupture during balloon mitral valvuloplasty using inoue balloon catheter. Catheter Cardiovasc Interv 1999; 48:331-2. [PMID: 10525240 DOI: 10.1002/(sici)1522-726x(199911)48:3<331a::aid-ccd21>3.0.co;2-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
14
|
Chui CH, Leung PHM, Lau FY, Wan TSK, Chan LC, Cheng G. Lack of structural rearrangement in c-kit and stem cell factor genes in Hong Kong Chinese patients with myelodysplastic syndromes or acute myeloid leukaemia. Hong Kong Med J 1998; 4:27-30. [PMID: 11832549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Stem cell factor is a haemopoietic growth factor that interacts with the c-kit-encoded transmembrane tyrosine kinase receptor during signal transduction in haemopoietic progenitor stem cells. We have screened 127 Chinese patients with myelodysplastic syndromes or acute myeloid leukaemia for structural rearrangements in the stem cell factor and c-kit genes using Southern blot analysis. No structural rearrangements were detected in any of the bone marrow samples that were tested. It seems that structural rearrangements in the stem cell factor and c-kit genes are rare in Hong Kong patients who have a haematological malignancy.
Collapse
Affiliation(s)
- C H Chui
- Department of Pathology, Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong
| | | | | | | | | | | |
Collapse
|
15
|
Abstract
Balloon mitral valvotomy (BMV) is safe and effective in patients with mitral stenosis (MS) and coexisting mild mitral regurgitation (MR). Influence of preexisting MR on late outcome of BMV is under evaluation. We included 77 patients without MR and 72 with MR in this study, and compared their immediate and late results in a mean follow-up of 33 +/- 24 months after BMV. Patients with coexisting MR were older and more frequently had significant valvular calcium and atrial fibrillation than patients without MR. After BMV, mitral valve gradient decreased, and cardiac output and mitral valve area by planimetry increased significantly (all p = 0.0001) in both groups. There was no difference in values of mitral valve gradient and cardiac output after BMV between the groups. Mitral valve area was significantly smaller in patients with preexisting MR. During follow-up, there were 11 patients (14%) in the group without MR and 24 (33%) in the group with MR developed cardiac events (p = 0.006). Cumulative event-free survival was 90% at the second year, 87% at the fourth year, and 69% at the sixth year, respectively, in the group without MR versus 78%, 62%, and 37%, respectively, in the group with MR (p = 0.0014). Cox regression showed that preexisting MR was a significant predictor for late cardiac events with a threefold increased hazard risk (p = 0.0025), but age, valvular calcium, echocardiographic score, and cardiac rhythm also played a culpable role. We conclude that preexisting MR is an important risk factor for poor, late outcome of BMV.
Collapse
Affiliation(s)
- H P Zhang
- Division of Cardiology, White Memorial Medical Center, Los Angeles, California, USA
| | | | | | | | | |
Collapse
|
16
|
Zhang HP, Ruiz CE, Allen JW, Lau FY. A novel prognostic scoring system to predict late outcome after percutaneous balloon valvotomy in patients with severe mitral stenosis. Am Heart J 1997; 134:772-8. [PMID: 9351747 DOI: 10.1016/s0002-8703(97)70063-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We developed a prognostic scoring system to predict the outcome of follow-up after balloon mitral valvotomy. The system incorporates seven variables before valvotomy: age, New York Heart Association class, fluoroscopic calcification, echocardiographic score, cardiac rhythm, mitral regurgitation, and mitral valve area. Each variable was coded with either 0 or 1 and a total score was between 0 and 7. The study included 150 patients with a mean follow-up of 33 +/- 24 months. In patients with scores of 0-1, 2-3, 4-5, and 6-7, the estimated cardiac event-free survival rate was 97%, 94%, 86%, and 68%, respectively, at 1 year; 95%, 88%, 74%, and 47%, respectively, at 3 years; and 92%, 82%, 61%, and 30%, respectively, 5 years after valvotomy (p = 0.0001). The hazard risk ratio for cardiac events was 1.7 times greater for every step up of the score (p = 0.0001). Our scoring system provides a simple but effective method to predict late outcome of balloon mitral valvotomy.
Collapse
Affiliation(s)
- H P Zhang
- Department of Cardiology, White Memorial Medical Center, Los Angeles, Calif., USA
| | | | | | | |
Collapse
|
17
|
Chui CH, Lau FY, Yau KS, Lee FC, Chan LC, Cheng G. Low frequency of c-kit expression and detection of an aberrant Kit message among Hong Kong Chinese myelogenous leukaemia patients. Cancer Lett 1997; 116:253-8. [PMID: 9215871 DOI: 10.1016/s0304-3835(97)00195-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The c-kit proto-oncogene encodes a transmembrane tyrosine kinase receptor. It is expressed by the primitive CD34 positive haemopoietic stem cells and interacts with the Kit ligand for signal transduction. It was reported to be expressed in over 80% of acute myelogenous leukaemia (AML) patients in North America and Japan. We analyzed 20 AML patients for c-kit expression using either Northern blot analysis or flow cytometry with the YB5.B8 anti-c-kit antibodies. Only 6 out of 20 AML patients expressed the c-kit mRNA or protein product. However, a previously unreported abnormal sized 1.7-1.9 kb transcript was detected in the blast cells of 1 AML patient, 1 acute mixed lineage leukaemia patient and 1 chronic myelogenous leukaemia (CML) patient in myeloblastic transformation. Our data suggested that in most Hong Kong Chinese AML patients, leukaemia transformation may have occurred at a c-kit negative stage. Alternatively, the abnormal sized c-kit transcript that was detected in some Chinese myeloid leukaemia patients may represent an aberrant c-kit receptor that plays an important role in leukaemogenesis.
Collapse
Affiliation(s)
- C H Chui
- Department of Pathology, Faculty of Medicine, The University of Hong Kong, Sha Tin
| | | | | | | | | | | |
Collapse
|
18
|
Chui CH, Lau FY, Chan AH, Tang JC, Hui CH, Lam CC, Chan LC, Cheng G. Expression of an abnormal sized c-kit transcript in Hong Kong Chinese acute lymphoblastic leukaemia patients. Clin Lab Haematol 1996; 18:261-3. [PMID: 9054699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Blast cells from a majority of acute myelogenous leukaemia (AML) patients express c-kit mRNA. However, c-kit expression has not been observed in patients with acute lymphoblastic leukaemia (ALL) and lymphoproliferative disease. We report here the detection of an abnormal sized c-kit mRNA in two Hong Kong Chinese patients with pre-B ALL and common ALL.
Collapse
Affiliation(s)
- C H Chui
- Department of Pathology, Faculty of Medicine, The University of Hong Kong
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Ruiz CE, Zhang HP, Lau FY. Inoue balloon: is it really easier? Cathet Cardiovasc Diagn 1996; 37:200. [PMID: 8808081 DOI: 10.1002/(sici)1097-0304(199602)37:2<200::aid-ccd20>3.0.co;2-m] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
|
20
|
|
21
|
Zhang HP, Gamra H, Allen JW, Lau FY, Ruiz CE. Comparison of late outcome between Inoue balloon and double-balloon techniques for percutaneous mitral valvotomy in a matched study. Am Heart J 1995; 130:340-4. [PMID: 7631618 DOI: 10.1016/0002-8703(95)90451-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The follow-up results between Inoue balloon (n = 43, group 1) and double-balloon (n = 43, group 2) mitral valvotomies were compared in a patient-to-patient matched study. Matching was based on patients' age, mitral valve echo score, fluoroscopic calcification, mitral valve area before valvotomy, and follow-up period. The mean follow-up period was 13 +/- 9 months for both groups. At follow-up, 72% of patients were symptom free in each group; 2 (4.7%) patients in group 1 and 1 (2.3%) patient in group 2 underwent mitral valve replacement surgery. Of these 3 patients, 2 died after surgery, 1 from each group. The mitral valve area by Doppler was 1.8 +/- 0.3 cm2 in group 1 and 1.8 +/- 0.4 cm2 in group 2 (p = 0.7); the area by echo planimetry was 1.7 +/- 0.3 cm2 in group 1 and 1.8 +/- 0.3 cm2 in group 2 (p = 0.3) at follow-up. Restenosis occurred in 5 (12%) patients from each group. The cumulative restenosis-free rate was 96% at 1 years, 78% at 2 years, and 58% at 3 years in group 1 and 98%, 76%, and 51%, respectively, in group 2 (p = 0.8). Balloon selection did not appear to influence the clinical outcome at follow-up. We conclude that both the inoue balloon and the double-balloon valvotomies are effective therapies with comparable follow-up results for patients with mitral stenosis.
Collapse
Affiliation(s)
- H P Zhang
- Department of Cardiology, White Memorial Medical Center, Los Angeles, CA 90033, USA
| | | | | | | | | |
Collapse
|
22
|
Affiliation(s)
- H P Zhang
- Department of Cardiology, White Memorial Medical Center, Los Angeles, California, USA
| | | | | | | | | |
Collapse
|
23
|
Abstract
We assessed immediate and late outcome in 55 patients with significantly calcified valves (group 1) after balloon mitral valvotomy and compared the results with those from 60 patients with noncalcified or minimally calcified valves (group 2). After valvotomy, mitral valve area increased from 1.03 +/- 0.30 cm2 to 1.64 +/- 0.35 cm2 (p = 0.0001) by echo planimetry in group 1 but was significantly smaller than the mitral valve area in group 2 after valvotomy (1.94 +/- 0.38 cm2; p = 0.0001). At a mean follow-up period of 30 months (range 2 to 81 months), 51% of patients in group 1 and 83% in group 2 were symptom free (p = 0.0002). In group 2, 15 (27%) patients and in group 2, 4 (7%) patients had cardiac events (p = 0.003). The risk ratio for cardiac events was 4.3 times greater in group 1 than in group 2. In group 1, the risk ratio for cardiac events was 3.2 times higher in patients age > or = 65 years and in patients with atrial fibrillation. The 6-year cumulative cardiac event-free survival rate was 64% in group 1 and 90% in group 2 (p = 0.005). In 75 (65%) patients who had follow-up echocardiographic study (35 in group 1 and 40 in group 2), mitral valve area decreased to 1.48 +/- 0.42 cm2 at follow-up in group 1 (p < 0.01) and to 1.77 +/- 0.50 cm2 in group 2 (p = 0.3). Restenosis occurred in 16 (46%) of 35 patients in group 1 and 10 (25%) of 40 in group 2 (p = 0.06).(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- H P Zhang
- Department of Cardiology, White Memorial Medical Center, Loma Linda, CA
| | | | | | | |
Collapse
|
24
|
Gamra H, Zhang HP, Clugston RA, Whittaker P, Allen JW, Lau FY, Ruiz CE. Thermodilution left-sided cardiac output for valve area determination after balloon mitral valvotomy. Am Heart J 1994; 128:934-40. [PMID: 7942487 DOI: 10.1016/0002-8703(94)90592-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This study was conducted to establish the validity of left-sided cardiac output measurement with a Swan-Ganz catheter and assess its accuracy in estimating mitral valve area (MVA) by the Gorlin formula. The use of right-sided cardiac output after balloon mitral valvotomy (BMV) can give inaccurate measurements for Gorlin-derived MVA because of the atrial septal defect (ASD) created during the procedure. The left-sided cardiac output was measured with a Swan-Ganz catheter (proximal port in the left atrium and then in the left ventricle, and distal port in the ascending aorta) in 10 consecutive patients before and after BMV. Gorlin-derived MVA cardiac output by this method was compared with (1) Gorlin-derived MVA by means of right-sided cardiac output with and without balloon occlusion of the ASD and (2) MVA measured by echocardiography. Before BMV, a close agreement with a good correlation between left-sided and right-sided cardiac output was found (r = 0.83, p = 0.006). Furthermore, Gorlin-derived MVA by cardiac output with either method was comparable with valve area by echo. After BMV, left-sided cardiac output correlated well (r = 0.92, p = 0.0002) and was comparable with right-sided cardiac output with occlusion of the ASD (mean difference 0.17 +/- 0.49 L/min, p = 0.3) but was significantly lower than the value obtained with open ASD (mean difference 0.93 +/- 0.77 L/min, p = 0.004). Comparison of the correspondent MVAs yielded similar results. Gorlin-derived MVA with left-sided cardiac output and MVA by echo were also similar.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- H Gamra
- Department of Cardiology, Loma Linda University Medical Center, CA 92354-0200
| | | | | | | | | | | | | |
Collapse
|
25
|
Ruiz CE, Zhang HP, Gamra H, Allen JW, Lau FY. Late clinical and echocardiographic follow up after percutaneous balloon dilatation of the mitral valve. Br Heart J 1994; 71:454-8. [PMID: 8011410 PMCID: PMC483723 DOI: 10.1136/hrt.71.5.454] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE To assess the outcome after attempted percutaneous balloon dilatation of the mitral valve in patients with severe mitral stenosis between February 1986 and June 1992. DESIGN Clinical state, mitral valve area, and restenosis at follow up were analysed. Mitral valve area as determined by the Gorlin formula, planimetry, and Doppler methods was compared before and after dilatation and at follow up. SETTING University hospital. PATIENTS 176 patients had serial clinical and Doppler echocardiographic follow up and 44 of them also underwent recatheterisation. RESULT At follow up 93% of patients were in New York Heart Association functional class I or class II. Mitral valve area (planimetry) increased from 0.97(0.24) cm2 before to 1.86(0.39) cm2 after dilatation (p = 0.0001) and then decreased to 1.72(0.39) cm2 at follow up (p < 0.001); mitral valve area (Doppler) increased from 1.01 (0.24) to 1.89 (0.42) cm2 (p = 0.0001) and then decreased to 1.78(0.40) cm2 (p < 0.05). The overall restenosis rate was 15% and over 90% of the patients were free from cardiovascular events. Age, valvar calcification, echocardiographic score, and mitral valve area after dilatation were found to be determinant predictors of restenosis. In patients who underwent recatheterisation, mitral valve area by the Gorlin method at follow up was comparable with that by planimetry and Doppler methods whereas a significant discrepancy between the three methods was noted immediately after dilatation. CONCLUSION Balloon dilatation of the mitral valve provided sustained anatomical and functional improvement in over 80% of patients at late follow up. Older age, heavy calcification, high echocardiographic score, and suboptimal immediate results are significant predictors of restenosis. Doppler echocardiographic examination is the procedure of choice for follow up evaluation.
Collapse
Affiliation(s)
- C E Ruiz
- Department of Cardiology, Loma Linda University Medical Center, Loma Linda University, California 92354-0200
| | | | | | | | | |
Collapse
|
26
|
Abstract
Resurgence of the transseptal procedure in the last decade has occurred coincident with the advent of therapeutic catheterizations and in particular mitral balloon vavuloplasty. As larger numbers of these procedures have been performed, experience shows that the position of intended septal puncture varies for each anticipated procedure and need not lie at the fossa ovalis, which is frequently displaced or inaccessible. Recognizing the dynamic alterations in septal and atrial anatomy that accompany the various combinations of valvular heart disease, the experienced interventionalist will use precatheterization echo and radiological techniques to enable precise and localized transseptal puncture. Using these techniques in 597 patients for valvular heart disease, we have had no deaths and a morbidity of 1.8% with the transseptal puncture.
Collapse
Affiliation(s)
- R Clugston
- Loma Linda University Medical School, White Memorial Medical Center, Hospital of the Good Samaritan, Los Angeles, California 90033
| | | | | |
Collapse
|
27
|
Ruiz CE, Gamra H, Mahrer P, Allen JW, O'Laughlin MP, Lau FY. Percutaneous closure of a secundum atrial septal defect and double balloon valvotomies of a severe mitral and aortic valve stenosis in a patient with Lutembacher's syndrome and severe pulmonary hypertension. Cathet Cardiovasc Diagn 1992; 25:309-12. [PMID: 1373992 DOI: 10.1002/ccd.1810250411] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
This is a 43-yr-old female presenting with recurrent atrial septal defect, closed surgically, 10 years prior, severe aortic and mitral stenosis, and severe tricuspid regurgitation. She was considered inoperable because of the severe pulmonary hypertension and the complexity of the disease. A percutaneous umbrella closure of the atrial septal defect in conjunction with mitral and aortic balloon valvotomies could be safely and successfully performed. After significant clinical and hemodynamic improvement, surgery was judged feasible, but was refused by the patient who suddenly expired 8 weeks later. The usefulness of percutaneous therapy as a rescue procedure and the management of patients with Eisenmenger's physiology are discussed.
Collapse
Affiliation(s)
- C E Ruiz
- Heart Institute, Loma Linda University Cardiology Service, Hospital of the Good Samaritan, Los Angeles, CA 90017
| | | | | | | | | | | |
Collapse
|
28
|
Abstract
The results of percutaneous mitral valvotomy by means of the Inoue single-balloon (N = 85, group 1) and the double-balloon (N = 322, group 2) techniques were compared in a nonrandomized study. The groups were not significantly different with regard to age, sex, calcification, or hemodynamic values before percutaneous mitral valvotomy. After percutaneous mitral valvotomy, patients in both groups had significant hemodynamic and clinical improvement. The increases in mitral valve area and cardiac output and the decreases in mitral valve gradient, mean pulmonary artery pressure, and mean left atrial pressure were greater in group 2. Mitral valve area determined by the Gorlin method increased 191% in group 2 and 106% in group 1; Doppler-determined mitral valve area increased 133% in group 2 and 98% in group 1. Optimal results were achieved in 93% of the patients in group 2 and 76% in group 1 (p less than or equal to 0.0001). In group 1, 6% of patients had a left-to-right shunt as shown by angiography versus 14% in group 2 (p less than or equal to 0.05). In group 2, 46% of patients had at least a 1+ increase in mitral regurgitation versus 52% in group 1. Among the patients who had an increase in mitral regurgitation, 36% of those in group 1 versus 9% in group 2 had a 2+ or more increase (p less than or equal to 0.001). The mean balloon diameter to anulus ratio was larger in group 2, and the larger the balloon diameter to anulus ratio, the greater the increase in mitral valve area.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- C E Ruiz
- Department of Interventional Cardiology, Hospital of the Good Samaritan, Loma Linda University, Los Angeles, CA 90017-2395
| | | | | | | | | | | |
Collapse
|
29
|
Ruiz CE, Lau FY. Congenital atresia of left main coronary artery: proposed mechanism for severe disabling angina in a patient with non-atherosclerotic single right coronary artery--a case report. Cathet Cardiovasc Diagn 1991; 23:190-3. [PMID: 1868532 DOI: 10.1002/ccd.1810230310] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A patient with progressive disabling angina was found to have a single right coronary artery with atresia of the left main coronary artery, and absence of any obstructive coronary disease. The patient required aortocoronary by-pass surgical reconstruction of a left main coronary artery to control her angina. Possible mechanisms for the development of her anginal pain are briefly discussed.
Collapse
Affiliation(s)
- C E Ruiz
- Heart Institute, Hospital of The Good Samaritan, Loma Linda University, Los Angeles, CA 90017
| | | |
Collapse
|
30
|
|
31
|
Affiliation(s)
- G S Konugres
- Department of Cardiology, Loma Linda University, White Memorial Medical Center, Los Angeles, Calif
| | | | | |
Collapse
|
32
|
Abstract
Percutaneous double balloon valvotomy for severe rheumatic mitral stenosis was successfully performed in 281 of 285 consecutive patients. The changes evoked were a decrease of the mean transvalvular gradient from 16 +/- 7 to 5 +/- 3 mm Hg, an increase in cardiac output from 3.8 +/- 1.0 liters/min to 5.4 +/- 1.5 liters/min and an increase in mitral valve area from 0.86 +/- 0.24 cm2 to 2.41 +/- 0.54 cm2. The mean pulmonary artery pressure decreased from 37 +/- 13 mm Hg to 27 +/- 12 mm Hg and the pulmonary vascular resistance decreased from 307 +/- 181 to 238 +/- 122 dynes/s/cm-5. Symptomatic improvement occurred in 272 of the 285 (95%) patients. There were 3 procedure-related deaths (1%). Postdilatation mitral regurgitation was not significant in most patients. Therefore, this procedure can be performed at a low risk with effective results and a fast recovery.
Collapse
Affiliation(s)
- C E Ruiz
- Department of Interventional Cardiology, Hospital of the Good Samaritan, Los Angeles, California 90017
| | | | | |
Collapse
|
33
|
Ruiz CE, Boltwood CM, Lau FY. Percutaneous double balloon aortic valvuloplasty in an adult patient with calcific aortic stenosis and a Bjork-Shiley prosthetic mitral valve. Cathet Cardiovasc Diagn 1988; 15:265-70. [PMID: 3228859 DOI: 10.1002/ccd.1810150411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Percutaneous transluminal balloon valvuloplasty is a new technique in interventional cardiology which to date has been applied successfully in the dilatation of all four cardiac valves. Although the different techniques appear to be quite effective, the safety of these procedures has not been fully explored. In particular, because of the close anatomic relationship of the aortic and mitral annuli, the safety of aortic valvuloplasty in patients with mitral valve prosthesis is unknown. Therefore, we report the applicability of a percutaneous double balloon valvuloplasty in an elderly patient with calcific aortic stenosis and a Bjork-Shiley mitral valve prosthesis.
Collapse
Affiliation(s)
- C E Ruiz
- Department of Medicine, White Memorial Medical Center-Loma Linda University School of Medicine, Los Angeles, California
| | | | | |
Collapse
|
34
|
Brooks SH, Allen JW, Edmiston WA, Lau FY, Blankenhorn DH. Clinical data versus noninvasive testing as an estimate of coronary status. Am J Cardiol 1983; 52:470-6. [PMID: 6604448 DOI: 10.1016/0002-9149(83)90010-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The step from coronary angiography to surgery is taken primarily on the basis of the ejection fraction (EF) and number of diseased vessels (NV), taken jointly as coronary status (CS). This study reviewed (1) how well EF, NV and CS are estimated from clinical data, (2) how much improvement is gained by adding noninvasive data, (3) how good this model is when applied to a larger cohort and (4) whether the decision to angiography can be made on the basis of CS estimated from clinical data alone. A quantitative definition of CS was established as a principal component of EF and NV. Estimates of EF, NV and CS were made from clinical data of 60 patients. Correlations with the actual values were EF 87%, NV 93% and CS 93%. When noninvasive data were added to this model, the correlations increased to EF 95%, NV 99% and CS 98%. When the clinical data model was applied to 169 patients, the correlations decreased to EF 77%, NV 71% and CS 74%. CS estimated from clinical data alone was set up as a test for angiography for 169 patients. This test had a sensitivity of 98% and a specificity of 63%, demonstrating the feasibility of using clinical data alone in deciding angiography.
Collapse
|
35
|
Affiliation(s)
- F. Y. Lau
- ; Department of Food Technology; Iowa State University; Ames IA 50011
| | - E. G. Hammond
- ; Department of Food Technology; Iowa State University; Ames IA 50011
| | - P. F. Ross
- ; Department of Food Technology; Iowa State University; Ames IA 50011
| |
Collapse
|
36
|
|
37
|
Abstract
The percentage of increase in total and MB creatine phosphokinase (CPK) after treadmill exercise was determined in 29 patients--ten patients with ST segment depression greater than 1 mm (group 1) and 19 patients with no ST segment depression (group 2). Values were determined pretest and 6, 12, and 24 hours after exercise. The mean exercise duration was 8 min, 18 sec. Total CPK increased within the normal range 12 hours after exercise in group 1 patients exercising less than 8 min, 18 sec, and in all patients exercising longer. The MB CPK remained unchanged after exercise in all patients. These data suggest that while normal range variation of total CPK occurs after treadmill exercise testing, the myocardium does not release MB CPK, regardless of the level of treadmill exercise our patients performed or the development of presumed ischemic ST segment responses. Abnormal elevation of MB CPK suggests myocardial damage.
Collapse
|
38
|
Abstract
The results of this investigation reveal that 39 per cent of patients in a study group of 46 patients with heart valve prostheses had gallstones if they survived 18 months or longer following valve replacement. In contrast, the prevalence of gallstones in a general population of autopsied rheumatic heart disease patients, including those who had been operated for severe valvular heart disease and had not survived for more than one month, was only 12 per cent. These findings suggest that gallstones are a frequent late complication of heart valve replacement.
Collapse
|
39
|
Edmiston WA, Yokoyama T, Kay J, Bilitch M, Lau FY. Ventricular tachycardia in a young adult with an apical aneurysm. West J Med 1978; 128:248-53. [PMID: 416599 PMCID: PMC1238076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
40
|
Abstract
A low incidence rate of thromboembolism has been reported in mitral porcine valve recipients. In contrast, 5 of 22 single mitral porcine valve recipients (23 percent) followed up in our clinic for a mean of 16 months had thromboembolic events. All patients but one were receiving long-term anticoagulant therapy. One thromboembolic event resulted in death, three in permanent neurologic deficits and one in a peripheral arterial occlusion. All five patients with emboli had atrial fibrillation and left atrial enlargement. Three had thromboembolic events before porcine heart valve implantation. In addition, five mitral porcine valve recipients who were not receiving anticoagulant therapy were examined at autopsy. Thrombus was identified in the left atrium in three patients, at the tissue-valve interface (sewing ring) in two, on the porcine valve cusps in one and in the right atrium in one. Factors influencing thrombus formation such as left atrial enlargement, atrial fibrillation and a prosthetic device are present after mitral porcine valve implantation and are indications for long-term anticoagulation therapy.
Collapse
|
41
|
Edmiston WA, Walters JR, Finck EJ, Turner AF, Lau FY. Angiographic demonstration of an acquired internal mammary-to-pulmonary artery fistula. Angiology 1977; 28:712-9. [PMID: 907221 DOI: 10.1177/000331977702801008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A patient with a continuous murmur due to flow through an internal mammary-to-pulmonary artery fistula is described. Previously reported cases have been thought to be congenital in origin. A history of an anteriorly placed chest tube suggests an acquired etiology for this malformation.
Collapse
|
42
|
Abstract
A total of 46 patients who survived aortic valve replacement with the present model Smeloff-Cutter prosthesis between 1968 and 1973 were followed up postoperatively. All patients received oral anticoagulant therapy. The average age at implantation was 44 +/- 13 (mean +/- standard deviation) years; 36 patients were male and 10 were female. The valve damage was caused by rheumatic disease in 19 (41 percent), infective endocarditis in 14 (30 percent), congenital heart disease in 7 (15 percent) and other factors in 6 (13 percent). Late death occurred in eight patients (17 percent). All available patients were followed up until December 1976. During the 8 years of follow-up study, seven patients, including four heroin addicts, had postoperative endocarditis (15 percent); five of the seven had cerebral involvement, possibly from septic emboli. Four patients were reoperated on; three had active endocarditis and one had a high transvalve pressure gradient. The mean follow-up time was 4.9 years per patient. Of the 38 living patients, 33 have functional improvement and are still being followed up. Only one patient had a bland embolism to a systemic artery. No ball variance or other types of material failure have been detected. Although the chronic aspects of valve disease remain after prosthetic valve replacement, the Smeloff-Cutter aortic prosthesis deserves strong consideration when selecting a rigid prosthesis for aortic valve replacement.
Collapse
|
43
|
Abstract
Frank lead ECG's from infants were studied for frequency content by introducing low-pass filters of 50, 75, 100, and 150 150 Hz bandwidths before obtaining computer measurements. Results indicated that a minimum bandwidth of 100 Hz is required to avoid amplitude error of 10 per cent or greater. This bandwidth requierement is essentially the same as that required for adult ECG's despite the fact that infant QRS durations are usually about half those of adults. Although the average infant ECG spectrum is likely to contain higher frequencies than the average adult ECG spectrum, duration values for Q, R, and S waves overlap in these populations to such an extent that bandwidth requirements are practically identical.
Collapse
|
44
|
Allen JW, Harrison EC, Camp JC, Borsari A, Turnier E, Lau FY. The role of serial echocardiography in the evaluation and differential diagnosis of pericardial disease. Am Heart J 1977; 93:560-7. [PMID: 851054 DOI: 10.1016/s0002-8703(77)80004-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Echocardiography is an established method for the diagnosis of pericardial effusion. Echographic findings in fibroadhesive disease have also been described. The interpretation of a changing serial echogram during the clinical course of pericardial disease has not been established. Sixteen patients with echographic evidence of pericardial effusion were followed with serial echographic studies. In seven, surgical or autopsy correlation was obtained. Because of the serial changes noted we undertook a study in dogs to clarify the problem of variability in intensity of sound reflected from the pericardial space. Three open-chested dogs were studied with rapid sequence surface echograms as blood introduced into the pericardial space was converted from the unclotted to the clotted state. In all three dogs blood clooting increased the intensity or sound reflected from the pericardial space. Our study of two patients with fibroadhesive pericardial disease documents serial changes in echoes from the pericardium and pericardial space accompanying the clinical evolution of the disease process, and suggests a method for avoiding the commonly encountered difficulty in proper identification of the pericardial and epicardial echoes. Our preliminary studies suggest that serial echograms should play an important role in the management of patients with pericardial effusion; further surgical/pathological correlations are required.
Collapse
|
45
|
Guller B, Lau FY, Dunn RA, Pipberger HA, Pipberger HV. Computer analysis of changes in frank vectorcardiograms of 666 normal infants in the first 72 hours of life. J Electrocardiol 1977; 10:19-26. [PMID: 833520 DOI: 10.1016/s0022-0736(77)80027-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Frank vectorcardiograms (VCGs) were collected on magnetic tape for 666 normal newborn infants at 1, 6, 12, 24, 36, 48, 60, and 72 hours after birth and analyzed by computers. The final total included 1,337 VCGs for white babies and 413 for blacks. No previous report has been made for the normal neonate with such a large sample, and no previous substantiation exists of possible age or sex differences at this early age. This study establishes a statistically significant change in vectorcardiographic patterns over the first three days, specifically in the measurements P duration, QRS duration, maximal spatial QRS amplitude, S in lead x, and T in lead z, as well as for several time-normalized QRS vectors. (P less than or equal to .005.) Racial differences were significant for T waves in lead z. This study supports the use of vectorcardiographic standards sensitive to the age of the newborn as well as to race.
Collapse
|
46
|
Zipser RD, Speckart PF, Zia PK, Edmiston WA, Lau FY, Horton R. The effect of ACTH and cortisol on aldosterone and cortisol clearance and distribution in plasma and whole blood. J Clin Endocrinol Metab 1976; 43:1101-9. [PMID: 186476 DOI: 10.1210/jcem-43-5-1101] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The mechanisms of increased aldosterone and cortisol metabolic clearance rates (MCR) following ACTH or cortisol administration were studied in 13 subjects undergoing cardiac catheterization and in 9 healthy controls. In control subjects, the MCR (plasma) of both steroids increased by 29% (aldosterone: from 936 +/- 57 to 1204 +/- 55 l/day/m2, cortisol: from 205 +/- 12 to 264 +/- 17 l/day/m2 +/- SE) after ACTH (12 units/h) for 1 to 4 h, and by 20 and 32%, respectively, after cortisol (12 mg/h) for 1 to 2 h. In contrast, aldosterone MCR (whole blood) did not change with ACTH or cortisol administration (from 1276 +/- 57 to 1330 +/- 59 l/day/m2), indicating that the plasma MCR increase results from a redistribution of aldosterone from plasma to red cells. Aldosterone splanchnic extraction was 92 +/- 1% (n = 12) with normal morning cortisol levels, and extraction was unchanged after ACTH administration. For cortisol, however, the splanchnic extraction increased from 8 +/- 0.8% to 17.8 +/- 5.0%, and the MCR (whole blood) likewise increased by 15 to 31% (from 295 +/- 23 to 357 +/- 30 l/day/m2), after ACTH or cortisol administration. In vivo and in vitro measurements (at 37 C) of tracer aldosterone concentration in plasma and in red cells showed an increase in distribution to red cells with increasing cortisol concentrations. The results suggest that a fraction of aldosterone is bound in plasma and displaced by cortisol into red cells. There is an increased aldosterone plasma MCR, but unaltered whole blood MCR, since the liver extracts aldosterone almost completely from both plasma and red cells. The increase in cortisol MCR (plasma) results from both an increased splanchnic extraction as plasma binding sites approach saturation and a redistribution into red cells.
Collapse
|
47
|
|
48
|
Abstract
The clinical diagnostic features of right ventricular myxoma are described in a recent patient and related to the 15 cases previously reported. The presence of a pulmonic systolic ejection murmur with a delayed (120 to 140 msec.) and accentuated pulmonic second sound, or calcification in the region of the right ventricular outflow tract should suggest this lesion. Cardiac catheterization with angiocardiography in diagnostic. Ga scanning may assist in the diagnosis and followup after surgical removal of the myxoma. Early surgical removal will avoid the possibility of sudden death.
Collapse
|
49
|
|
50
|
Mendenhall RC, Abrahamson S, Girard RA, Lau FY. Profile of the cardiologist: training and manpower requirements for the specialist in adult cardiovascular disease. Study research design. Am J Cardiol 1974; 34:397-407. [PMID: 4415320 DOI: 10.1016/0002-9149(74)90005-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|