ABSTRACT
Objective To evaluate the function of tricuspid annulus using omni-directional M-mode echocardioraphy(OME) in patients during mitral valve replacement(MVR) ,and provide a reference for clinical decision about concomitant tricuspid annuloplasty for patients under MVR . Methods Twenty-five normal subjects were selected as control group . Thirty-three patients under MVR for mitral stenosis were divided into tricuspid annuloplasty group( TVP group , n =17) and non-tricuspid annuloplasty group( NTVP group , n =16) .Transesophageal echocardiography ( TEE) was performed before and after surgery . The right ventricular fractional area change( RVFAC) ,maximal tricuspid annular diameter( TADmax) ,tricuspid annular fractional shortening( TAFS) and tricuspid regurgitation( TR) degree were detected by 2D and color Doppler echocardiography . OME and quantitative tissue velocity imaging(QTVI) were used to measure the peak systolic velocity of tricuspid annular ,which were defined as Sm and St . Results In the TVP group , TADmax decreased and TR degree improved significantly compared with preoperative date ( P< 0 .05) . Preoperative Sm had nagative correlation with TADmax/BSA ( r = -0 .53 , P <0 .01) and RVFAC( r =0 .87 , P < 0 .01) ,and positive correlation with TAFS ( r = 0 .68 , P < 0 .01) . Conclusions The peak systolic velocity of tricuspid annulus measured by OME can assess the function of tricuspid annulus additionally ,and provide a reference for clinical decision about concomitant tricuspid annuloplasty for patients under MVR .
ABSTRACT
Objective To develop a candidate reference method for the determination of serum creatinine and to evaluate the ac-curacy of conventional detection systems though method comparison to achieve traceability .Methods The candidate reference method was established according to the sarcosine oxidase and the accuracy and reliability of the method was verified through par-ticipation in international reference laboratories EQA activities (IFCC-RELA) .20 fresh single human serum samples with different concentration and calibrator were simultaneously measured by using conventional detection system and candidate reference method . Results The calibration curve for serum creatinine was linear in the concentration range from 50-2 000 μmol/L with a correlation coefficient of 0 .999 9 under the optimum experimental conditions (the linear equation was Y=0 .000 884 2X-0 .000 325 3) and the imprecision was less than 1 .0% .The proposed method has been applied to the determination of RELA samples with satisfactory re-sults .The measured results with conventional detection systems were consistent with candidate reference method ,and the slope of the regression equation was 1 .005 6 .Conclusion The candidate reference method of serum creatinine is successfully established and which can be used for traceability and standardization .It may provide an effective way for conventional detection system traceable to the reference method or reference material .
ABSTRACT
Objective To establish a candidate reference method for the determination of serum lithium based on ion chromatog-raphy and evaluate its analytical performance.Methods A simple sample treatment procedure,which can be remove the proteins and/or organics in human serum,has been developed for the determination of serum lithium.Method precision was evaluated with different concentration of fresh human serum and EQA sample RELA-A/B.Method accuracy was investigated with the recovery ex-periments in fresh human serum and RELA-A/B sample.Results The linear equation was Y =0.817 1X -0.001 3 with a correla-tion coefficient of 0.999 95 under the optimum experimental conditions,the detection limit (3S/N)for lithium was 6 μg/L and the imprecision was less than 1.0%.The results of the recovery experiments indicated that the recoveries were reasonable for the deter-mination of serum lithium,in a range of 99%-101%.Conclusion The candidate reference method of lithium was successfully es-tablished and which can be used for traceability and standardization.It may provide an effective way for routine testing of lithium traceable to the reference method/reference material.