KRAS mutation in the primary or acquired resistance of Chinese NSCLC to EGFR tyrosine kinase inhibitors

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Background: Prevalence of KRAS mutation in Asian NSCLC is different to population of white ethnicity. Data about KRAS mutation after development of resistance to EGFR tyrosine kinase inhibitors (TKIs) are rare. This study was to investigate the prevalence of KRAS mutation in Chinese NSCLC after primary or acquired resistance to EGFR TKIs. Methods: 155 EGFR TKI-naive NSCLC patients and corresponding tumor specimens were collected to establish baseline of KRAS mutation. 45 specimens from six patients with primary resistance to TKIs and twenty-nine patients with acquired resistance to TKIs were analyzed. Genomic DNA was prepared after purified cancer cells were isolated by laser microdissection. Mutations in codon 12 and 13 of the KRAS gene in TKI-naive patients were analyzed by direct sequencing. Mutations in TKI-resistant patients were meanwhile detected by DxS KRAS Mutation Test Kit and direct sequencing. Results: KRAS mutation (G12X) was detected in 7.1% (11/155) of the TKI- naive patients by direct sequencing. In 6 primary resistant patients (two paired specimens and four resistant specimens) and in 29 acquired resistant patients (eight paired specimens and twenty-one resistant specimens), absence of KRAS mutation was detected in all pre- treatment and post-treatment tissues by both methods. Conclusions: KRAS mutation exists in TKI-naive NSCLC patients instead of TKI-resistant setting. KRAS mutation couldn’t thoroughly explain the primary resistance to EGFR TKIs and it might not be the crucial consideration in the mechanisms of acquired resistance.

No significant financial relationships to disclose.

A phase II clinical and biological study of lithium carbonate (Li) in patients with low-grade neuroendocrine tumors

e15662

Background: Low-grade neuroendocrine tumors (NETs), such as carcinoid, islet cell tumors, and medullary thyroid carcinomas, respond poorly to chemotherapy, and effective, less toxic therapies are needed. Glycogen Synthase Kinase (GSK)-3β, a multifunctional protein kinase, has been shown to regulate growth and hormone production in NETs. Use of lithium carbonate (Li) in murine models suppressed carcinoid cell growth, reduced GSK-3β levels and reduced expression of chromogranin A. This study assessed the efficacy of Li in patients with NETs. Methods: Eligible pts had pathologically-proven, measurable low-grade NETs. Prior treatment was allowed if completed >4wks prior to registration. Standard eligibility criteria were used, and use of medications affecting Li metabolism or levels were prohibited. A single-arm, open-label, two-stage Phase II design was used. Li was dosed at 300mg orally TID with meals, titrated to a target serum level of 0.8–1.0mmol/L. The primary endpoint was objective tumor response by RECIST. Secondary endpoints included overall survival, progression-free survival, decrease of serum tumor markers, toxicity, and quality of life. Results: 15 pts were enrolled between 10/3/07and 7/17/08; 6 men, 9 women. The median age was 58 (range 47–74). Patients’ diagnoses were carcinoid tumor for 8 subjects, islet cell tumor for 5 subjects, and 2 unknown primary sites. ECOG PS was 0 (6 patients) or 1 (9 patients). Two pts came off study due to side effects (tremor, dizziness/abdominal pain). There were no radiographic responses. Due to an early stopping rule requiring at least 1 objective response in the first 13 evaluable pts, the study was closed to further accrual. 13 patients had pre- and post-therapy biopsies. Evaluation of quality of life and GSK-3β levels in tumor tissue is ongoing. Conclusions: Li was ineffective at obtaining a radiographic response in our 13 evaluable patients who were treated as part of this study. We will determine from tumor biopsies whether Li was effective at phosphorylating GSK-3β in order to make conclusions about GSK-3β as a therapeutic target for future NET treatment strategies. Funded through NIH grant R21CA117117- 01A2 and CTRC grant 1ULRR025011.

No significant financial relationships to disclose.

In vitro sequence-dependent interaction between paclitaxel and gefitinib in human lung cancer cell lines

e22025

Background: Cytotoxicity chemotherapy has been standard first line treatment for advanced NSCLC. Clinical trials comparing first line EGFR TKI therapy over cytotoxicity chemotherapy are under investigation in phase III trials. The aim of this study is to test the hypothesis that paclitaxel followed by gefitinib would be superior to the opposite order in EGFR TKI resistant cell lines because of cell signaling pathway and cell cycle interaction. Methods: we have used EGFR-TKI resistant human lung cancer cell lines A549, H1975 and H1650 as an in vitro model for defining the differential effects of opposite sequence of combination of cytotoxic drug and anti- EGFR agents on cell growth, signaling pathway, cell cycle distribution and induction of apoptosis. Results: Paclitaxel 24 hours followed by gefitinib 72 hours in A549, H1975 and H1650 cells produced synergistic effects, while the reverse sequence produced antagonistic effects. Exposure to paclitaxel resulted in an increased pEGFR and pAKT level, this increase of phosphorylation can be inhibited by the following gefitinib exposure, while the reverse sequence resulted in no change in EGFR and AKT phosphorylation. We confirmed that gefitinib arrested the cells in G1, paclitaxel arrested cells in S phase. The sequence of paclitaxel followed by gefitinib cause cells arrested in G1, while the reverse sequence cause cells arrested in S and G2 phase. Conclusions: These findings suggest that the sequence of paclitaxel followed by gefitinib may be superior to the reverse sequence in gefitinib resistant NSCLC, and support the investigation of these sequential treatment in the clinical setting. This work was supported by the grants from the National Natural Science Foundation of China (No. 30772531).

No significant financial relationships to disclose.

Phase I study of vandetanib (V) and bevacizumab (B) combination therapy evaluating the VEGF and EGF signal transduction pathways in adults with solid tumors and NHL

3522

Background: (V), a small molecule tyrosine kinase inhibitor, has strong inhibitory activity against VEGFR-2 and the EGF RTK. (B), a humanized anti-VEGF monoclonal antibody, blocks the binding of human VEGF to its receptors. We proposed that dual blockade of the VEGF pathway provides an added therapeutic effect compared with either agent alone. Methods: A standard 3–6 pt/cohort design, dose-escalation Phase I study was performed. (V) was self-administered PO, days 1–21 of each 21-day cycle. (B) was administered by IV infusion Q 3 wks. Objectives: Determine the toxicity profile and the MTD of the combination of (V+B); evaluate (V) pharmacokinetics, changes in tumor vascularity by dynamic contrast enhanced MRI (DCE-MRI) and effects of (V+B) treatment on circulating endothelial progenitors and mature circulating endothelial cells. Eligibility: ECOG ≤ 2, adequate organ function. The MTD is the dose level at which no more than 1 of 6 patients experience DLT during the first 2 cycles of treatment, and the dose below at which at least 2 (of ≤6) patients have DLT due to drug treatment. Results: 9 pts have been accrued to date. Diagnosis: pancreatic-1, NSCLC-1, colorectal-3, peritoneal mesothelioma-1, melanoma-1, NHL-1, jejunal adenocarcinoma (JAC)-1. 1 DLT (gr 3 Allergic reaction) was observed at DL 2. HTN was the most common toxicity at DL 2. Other gr 2–3 toxicities seen beyond 2 cycles included: diarrhea, elevated creatinine, leucopenia, anemia, thrombocytopenia, hemorrhage, prolonged QTc interval, proteinuria, rash (hand-foot syndrome / acneiform). Partial Response (PR) was achieved in 2 pts (pancreatic 14 mos + and JAC 6 mos); disease stabilization in 5 pts (4 mos +). DCE-MRI results showed a reduction in the parameters of permeability, (ktrans and kep), associated with one PR. Conclusions: We decided not to escalate beyond DL 2 due to the gr 2–3 toxicities observed with chronic therapy. We recommend (V): 200mg daily and (B): 5mg/kg IV q3 weeks as the Phase II dose.

[Table: see text]

No significant financial relationships to disclose.

Cetuximab (C) and bevacizumab (B) in patients with recurrent or metastatic head and neck squamous cell carcinoma: An updated report

6049

Background: Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) represent important therapeutic targets in SCCHN. Cetuximab (C), an IgG1 monoclonal antibody against EGFR, has single agent activity in SCCHN. Upregulation of VEGF has been associated with C resistance, thus, combined targeting may enhance anti-tumor activity. We designed a phase II trial of bevacizumab (B), an anti-VEGF humanized monoclonal antibody, with C to evaluate this hypothesis. Methods: Eligible patients have recurrent or metastatic SCCHN, measurable disease (RESIST), ECOG performance status (PS) 0–2, and no history of bleeding or thrombosis. Up to 1 regimen (without an EGFR inhibitor) for recurrent or metastatic disease and prior chemoradiotherapy with curative intent are allowed. Treatment consists of weekly cetuximab, 250 mg/m2 (after a loading dose 400 mg/m2) and bevacizumab, 15 mg/kg given intravenously every 21 days, until disease progression. The primary endpoint is the objective response rate. Sample size is 45 eligible patients. Specific biomarkers relating to EGFR and VEGFR signaling will be evaluated in tumor tissues and blood samples. Results: 28 patients enrolled (27 eligible). Median age 60 years (range 33–92); male 19; PS 0 (7 pts), PS 1 (18), PS 2 (2). All had prior RT, and 26 had chemotherapy. A median of 4 cycles were given (range, 1–12). Best response in 25 evaluable patients: 5 (20%) PR (1 was uncomfirmed), 14 (56%) SD, and 6 (24%) PD. Progression-free survival was 2.8 months and median overall survival was 8.1 months. Grade (G) 3 adverse events included: hemorrhage (from a benign neck ulcer), 1; hypertension, 2; infection, 2; rash, 2; dysphagia, 4; hypophosphatemia, 1; and fatigue, 1. G 4 AEs: proteinuria, 1. One pt died of aspiration pneumonia, with possible cardiac ischemia of uncertain relationship to study drugs. Conclusions: Preliminary results show that cetuximab and bevacizumab is an active regimen in SCCHN with rare serious toxicities. In particular, our results establish the safety of this bevacizumab-based regimen in regards to bleeding complications in SCCHN. Study accrual continues and biomarker analysis is planned. (Supported by U01 CA099168–01 and P50 CA097190)

No significant financial relationships to disclose.

Phase I study combining an IGFR inhibitor (IMC-A12) and an mTOR inhibitor (temsirolimus) in patients with solid tumors or lymphoma

e14535

Background: IMC-A12 is a fully humanized IgG1/ lambda monoclonal antibody directed at the type I Insulin-Like Growth Factor Receptor (IGF-IR). Temsirolimus, an ester of the macrocyclic immunosuppressive agent sirolimus, is a cytostatic cell cycle inhibitor, which specifically inhibits the mammalian target of rapamycin (mTOR). A paradoxical increase in AKT activation by an mTOR inhibitor through an IGF-1R-dependent mechanism may compromise the therapeutic effect of mTOR inhibitors. Hence we evaluated the combination of temsirolimus and IMC-A12. Methods: This standard “3+3” design used a fixed dose of 25 mg IV weekly of temsirolimus with an escalating weekly dose of IV IMC-A12 at 3 mg/kg, 4 mg/kg and 6 mg/kg with no intrapatient dose escalation. The goal of this study is to define the MTD and to evaluate the biologic effects and metabolic activity of IMC-A12 and temsirolimus, individually and in combination. Patients with advanced solid tumors and lymphoma are eligible. No history of diabetes is allowed in dose escalation cohorts. Results: To date, 11 patients (4 males and 7 females, median age 47) with various solid tumor histologies have been enrolled across 3 dose cohorts with the current dose cohort at 6 mg/kg weekly IV of IMC-A12 and 25 mg weekly IV of temsirolimus. The MTD has not been determined. The most common grade 1 and grade 2 toxicities have been dysgeusia (n=5), fatigue (n=5), hyperglycemia (n=6), hypertriglyceridemia (n=6), leucopenia (n=4), mucositis (n=4), and ocular flashes of light (n=3). No grade 3 or 4 toxicity lasted more than 7 days (nausea n=1; vomiting n=1; thrombocytopenia n=1). Two patients (metastatic prostate cancer and metastatic breast cancer) demonstrated prolonged stable disease for 4 and 6 months, respectively. Conclusions: Preliminary data suggest that the combination is well tolerated and that it warrants further investigation. The expansion phase of this study will evaluate the biologic effects and metabolic activity of IMC-A12 and temsirolimus, individually and in combination, through the use of RPPA (Reverse Phase Protein Assays) and PET scans.

[Table: see text]

Flesh color association with polymorphism of the tyrosinase gene in different Chinese chicken breeds

In order to study genetic variation of tyrosinase gene in four different flesh color chicken breeds selected from special districts including Guyuan, Wenchang, Tibetan and Hisex chicken, five loci of the TYR gene exon-1 and one locus of 5' flanking region were analyzed in PCR-SSCP and DNA sequencing. The results indicated that there were polymorphisms only at TYR1 and TYR3 locus. At TYR1 locus located in exon-1, there were three genotypes (TT, CC, TC), respectively, in three Chinese chicken breeds, and Genotype CC had not been detected in Hisex chicken. At TYR3 locus located in 5' flanking region, there were three genotypes (GG, AA and GA) in Chinese local chicken breeds and genotype AA had not been detected in Hisex chicken breed. It was concluded that there were many variations of TYR gene in Chinese local chicken breeds. DNA sequencing of PCR products for different genotypes showed that there were two mutation sites, respectively, C to T at TYR1 locus and G to A at TYR3 locus. Mutation at TYR1 locus did not cause any amino acid variation. The chi-square analysis revealed that there were significant statistical differences generally between flesh color and the two loci among four chicken populations (P < 0.01). Our results suggested that the flesh color was related to genotype of TYR gene in Chinese chicken breeds. This study provided original information for elucidating the possible roles of exon-1 of TYR gene and 5' flanking region in chickens with different flesh color chicken.

Effects of magnesium salt concentrations on B-DNA overstretching transition

In this study, we use optical tweezers to investigate the ionic effects of magnesium salt solutions on the overstretching transition of single B-DNA molecules. The experimental data are compared with those in sodium salt solutions. The overstretching transition force increases when the NaCl or MgCl(2) salt concentration increases. Magnesium cations have much stronger effects on the overstretching transition force than sodium cations. For both NaCl and MgCl(2) salt solutions, the overstretching transition force is linear with the natural logarithm of salt concentration, which confirms the theory proposed in previous paper. The modified ZZO model is applied to study the electrostatic contribution of magnesium salt solutions to the overstretching transition of single B-DNA molecules. The consistency between the experimental data and analytical results shows that the modified ZZO model can simulate the transition behavior of single B-DNA molecules in different NaCl and MgCl(2) salt solutions.

Impact of early adolescent psychiatric and personality disorder on long-term physical health: a 20-year longitudinal follow-up study

BACKGROUND

Evidence regarding the long-term separate and combined impact of adolescent psychiatric disorder and personality disorder (PD) on physical health is absent.

METHOD

A total of 736 people randomly selected in childhood were contacted for home or telephone interviews four times over 20 years. DSM Axis I disorders and Axis II PDs were assessed at mean age 13.7 years in 1983 and physical health was assessed in 1985-1986, 1991-1994 and 2001-2004.

RESULTS

Comparisons were made between 506 adolescents without Axis I disorder or PD and adolescents with Axis I disorder or PD or both. Adolescents with an Axis I disorder (n=150) had significantly higher odds of pain and physical illness and poorer physical health. Adolescents with a PD (n=149) had higher odds of pain and physical illness and poorer physical health and a more rapid decline in physical health. In addition, the 81 participants with an Axis I disorder without co-morbid PD had poorer physical health, but this effect did not reach statistical significance, whereas the 80 participants with a PD but no Axis I disorder reported significantly more pain and more rapid decline in physical health. However, the 69 participants with co-morbid Axis I disorder and PD had the highest rates of pain and physical illness and the worst physical health.

CONCLUSIONS

Co-morbid PD accounted for many of the associations of adolescent Axis I disorder with physical health over the ensuing two decades. Co-morbid adolescent Axis I disorder and PD represent a particularly high risk for physical health.

Learning Document-Level Semantic Properties from Free-Text Annotations

This paper presents a new method for inferring the semantic properties of documents by leveraging free-text keyphrase annotations. Such annotations are becoming increasingly abundant due to the recent dramatic growth in semi-structured, user-generated online content. One especially relevant domain is product reviews, which are often annotated by their authors with pros/cons keyphrases such as ``a real bargain'' or ``good value.'' These annotations are representative of the underlying semantic properties; however, unlike expert annotations, they are noisy: lay authors may use different labels to denote the same property, and some labels may be missing. To learn using such noisy annotations, we find a hidden paraphrase structure which clusters the keyphrases. The paraphrase structure is linked with a latent topic model of the review texts, enabling the system to predict the properties of unannotated documents and to effectively aggregate the semantic properties of multiple reviews. Our approach is implemented as a hierarchical Bayesian model with joint inference. We find that joint inference increases the robustness of the keyphrase clustering and encourages the latent topics to correlate with semantically meaningful properties. Multiple evaluations demonstrate that our model substantially outperforms alternative approaches for summarizing single and multiple documents into a set of semantically salient keyphrases.

Superconductivity at 56 K in samarium-doped SrFeAsF

We synthesized the samples Sr(1-x)Sm(x)FFeAs with a ZrCuSiAs-type structure. These samples were characterized by resistivity and susceptibility. It is found that substitution of rare earth metal for alkaline earth metal in this system suppresses the anomaly in resistivity and induces superconductivity. Superconductivity at 56 K in nominal composition Sr(0.5)Sm(0.5)FFeAs is realized, indicating that the superconducting transition temperatures in the iron arsenide fluorides can reach as high as that in oxypnictides with the same structure.

Unusual doping dependence of the electronic structure and coexistence of spin-density-wave and superconductor phases in single crystalline Sr1-xKxFe2As2

The nature of the spin-density wave (SDW) and its relation with superconductivity are crucial issues in the newly discovered iron-pnictide superconductors. Particularly, it is unclear whether the superconducting phase and SDW are truly exclusive from each other. We here report splittings of the band structures in Sr1-xKxFe2As2 (x=0, 0.1, 0.18), and their unusual doping dependence. Our data on single crystalline samples prove that the SDW and superconductivity could coexist in iron pnictides.

Anisotropy in the electrical resistivity and susceptibility of superconducting BaFe2As2 single crystals

We report that sizable single crystals of BaFe2As2 have been grown with the self-flux method. Measurements and anisotropy of intrinsic transport and magnetic properties from high-quality single crystal are first presented. The resistivity anisotropy (rho{c}/rho{ab}) is as large as 150 and independent of temperature. In contrast to the susceptibility behavior observed in polycrystalline samples, no Curie-Weiss behavior is observed, and a linear-T dependent susceptibility occurs from the spin-density-wave transition temperature, (T{s}), to 700 K. This result suggests that strong antiferromagnetic correlations are present well above T{s}. A twofold symmetry of susceptibility in the ab plane indicates a stripelike spin structure as observed by neutron scattering. The resistivity minimum is strongly dependent on the magnetic field, suggesting that the upturn of the resistivity at low temperatures should be related to spin fluctuation.

A coding SNP of LHX4 gene is associated with body weight and body length in bovine

Heterozygous mutations in LHX4 are associated with combined pituitary hormone deficiency. In this study, the polymorphism of LHX4-HaeIII locus was revealed in 822 individuals from four Chinese cattle breeds. The PCR-RFLP analysis showed that there were three genotypes: GG, GA, AA. The frequencies of genotype GG ranged from 0.6620 to 0.9789 in analyzed populations. The genotypic frequencies of LHX4 locus in the four populations all agreed with Hardy-Weinberg equilibrium (P > 0.05). Distributions of genotypic frequencies of different breeds (QC, NY, JX, CH) at this locus were found to be significantly different based on a chi(2) test (P < 0.001). The genetic diversity analysis revealed the JX cattle possessed intermediate genetic diversity, and the other three Chinese cattle breeds belonged to poor genetic diversity. Correlation analysis with growth traits in the NY breed indicated that: the animals with genotype GA had greater body weight than those with genotype GG (P < 0.05); the animals with GA genotype owned significantly longer body length than the ones with GG genotype (P < 0.05) at 18 and 24 months.

Effects of recombinant human relaxin upon proliferation of cardiac fibroblast and synthesis of collagen under high glucose condition

Cardiac fibrosis is a key component of diabetes and involves the proliferation and differentiation of matrix-producing fibroblasts. We determined the influence of high glucose (HG) conditions on cardiac fibroblasts (CF) functions and the effects of recombinant human (rh) relaxin (RLX) in these responses. We cultured neonatal rat CF in either normal glucose (NG) or HG media. The mRNA of procollagen types I and III, and RLX-1 were assessed by real time PCR and procollagen type I C-terminal peptide (PICP) and procollagen type III amino terminal peptide (PIIINP), matrix metalloproteinases 2 (MMP2), MMP9 were assessed by enzyme linked immunosorbent assay. The results are as follows: a) CF proliferation was significantly increased by HG; rhRLX significantly inhibited HG fibroblast proliferation, while it had no marked effect on CF proliferation in NG. b) CF treated with HG significantly increased the production of PICP and PIIINP. rhRLX had no marked effect on production of PICP and PIIINP in NG. rhRLX blocked the HG-induced increases in collagen synthesis. c) The production of MMP2 and MMP9 is significantly increased by HG. rhRLX decreased overproduction of MMP2 and MMP9 in the presence of HG. d) The RLX- 1 mRNA expression of HG group was higher than in the NG group. We concluded that rhRLX could inhibit both the proliferation of CF and the synthesis of collagen under the HG condition. HG concentration could stimulate the expression of endogenous RLX.

A CMOS neuroelectronic interface based on two-dimensional transistor arrays with monolithically-integrated circuitry

The ability to monitor and to elicit neural activity with a high spatiotemporal resolution has grown essential for studying the functionality of neuronal networks. Although a variety of microelectrode arrays (MEAs) has been proposed, very few MEAs are integrated with signal-processing circuitry. As a result, the maximum number of electrodes is limited by routing complexity, and the signal-to-noise ratio is degraded by parasitics and noise interference. This paper presents a single-chip neuroelectronic interface integrating oxide-semiconductor field-effect transistors (OSFETs) with signal-processing circuitry. After the chip was fabricated with the standard complementary-metal-oxide-semiconductor (CMOS) process, polygates of specific transistors were etched at die-level to form OSFETs, while metal layers were retained to connect the OSFETs into two-dimensional arrays. The complete removal of polygates was confirmed by high-resolution image scanners, and the reliability of OSFETs was examined by measuring their electrical characteristics. Through a gate oxide of only 7nm thick, each OSFET can record and stimulate neural activity extracellularly by capacitive coupling. The capability of the full chip in neural recording and stimulation was further experimented using the well-characterised escape circuit of the crayfish. Experimental results indicate that the OSFET-based neuroelectronic interface can be used to study neuronal networks as faithfully as conventional electrophysiological tools. Moreover, the proposed simple, die-level fabrication process of the OSFETs underpins the development of various field-effect biosensors on a large scale with on-chip circuitry.

Assessment of mitral valve volume by quantitative three-dimensional echocardiography in patients with rheumatic mitral valve stenosis

BACKGROUND

Thickening of mitral leaflets in rheumatic mitral valve stenosis is well described in necropsy studies; however, volume computation of the thickening mitral leaflets has not been attempted. 4trial fibrillation is one of the complications of rheumatic mitral stenosis. Quantitative assessment of thickened mitral valve and its relation to clinical complications is clinically desirable.

HYPOTHESIS

The study was undertaken to compare measurement of mitral valve volume in normal subjects and in patients with rheumatic mitral valve stenosis.

METHODS

An HP Sonos 2500 echocardiographic system with 5 MHz multiplane transesophageal transducer was used for data acquisition, and TomTec Echoscan computer setup was used to off-line volume computation. Study subjects included 10 normal subjects (mean age 44.8 years) and 36 patients with rheumatic mitral valve stenosis (22 female, 14 male) with an age range of 25 to 69 years (mean age 47 +/- 9.6 years). Mitral valve volumes were compared between the normal subjects and patients with mitral valve stenosis, and further comparison was made between the sinus rhythm (SR) and atrial fibrillation (AF) groups in patients with mitral valve stenosis. In all study subjects, the mitral valve area (MVA) was determined by two-dimensional echocardiography.

RESULTS

Quantitative three-dimensional (3-D) echocardiography showed that mitral valve volume was significantly larger in patients with mitral valve stenosis than in normal subjects (9.0 +/- 2.2 and 4.5 +/- 0.7 ml, respectively, p < 0.001). When patients with mitral valve stenosis were divided into the SR and AF groups, mitral valve volume was found to be significantly larger in the AF group than in the SR group (9.76 +/- 2.2 ml. and 7.72 +/- 1.5 ml, respectively, p < 0.01) and patients in the AF group tended to be older (p < 0.05) with larger left atrial diameter (LAD) (p < 0.01). However, MVA between the two groups showed no statistical significance (1.1 +/- 0.43 and 1.0 +/- 0.34 cm2, respectively, p > 0.2). When the study subjects were divided into two groups (< 50 and > or = 50 years) according to age, the comparison of mitral valve volume between these two groups (9.37 +/- 2.18 and 8.56 +/- 2.14 ml, p > 0.2) showed no statistical significance.

CONCLUSIONS

Quantitative 3-D echocardiography can be applied for the measurement of mitral valve volume in vivo. Patients with rheumatic mitral valve stenosis with atrial fibrillation have a propensity to have a larger mitral valve volume and are older than the patients with sinus rhythm; however, the age per se does not seem to be a cause for larger mitral valve volume.