Assessment of regional left ventricular function with multidetector-row computed tomography versus magnetic resonance imaging

This study compares quantitative and qualitative information on global and regional left ventricular (LV) function obtained with multidetector-row computed tomography (MDCT) with that obtained with magnetic resonance imaging (MRI) in patients with a high prevalence of LV wall motion abnormalities. Thirty patients (19 male, 63.7+/-15.1 years) with myocardial infarction (n=12), coronary artery disease (n=9), arrhythmogenic right ventricular cardiomyopathy (n=6), and dilation cardiomyopathy (n=3) were included. Segmental LV wall motion (LV-WM) was assessed using a 4-point scale. Wall thickness measurements were calculated in diastolic and systolic short axis images. Two hundred and fifty-two out of 266 (94.7%) normal and 189 out of 214 (88.3%) segments with decreased wall motion were correctly identified by MDCT, yielding a sensitivity of 88% and specificity of 95% for identification of wall motion abnormalities. LV-WM scores were identical in 86.7% of 480 segments (kappa=0.809). MDCT had a tendency to underestimate the degree of wall motion impairment. Interobserver agreement was lower in MDCT (66.5%) than in MRI (89.1%; p<0.01). Normokinetic segments are reliably identified with MDCT. Sensitivity for detection and accurate classification of LV wall motion abnormalities need to be improved. Better temporal resolution of the CT system seems to be the most important factor for enhancing MDCT performance.     

Assessment of left ventricular diastolic function by gated single-photon emission tomography: comparison with Doppler echocardiography

Gated single-photon emission tomography (SPET) is not yet an established procedure for the evaluation of left ventricular (LV) diastolic function. This study examined diastolic function derived from gated SPET in comparison with an established diagnostic tool, Doppler echocardiography. We examined 37 consecutive patients with normal sinus rhythm who underwent gated technetium-99m tetrofosmin SPET. A gated SPET program was used with a temporal resolution of 32 frames per R-R interval. We obtained the Doppler transmitral flow velocity waveform immediately before gated SPET image acquisition. Patients who showed a ratio of peak early transmitral flow velocity to atrial flow velocity (E/A) of >1 or whose R-R intervals differed by >5% between Doppler echocardiography and gated SPET were excluded from this investigation. We compared diastolic indices and presumed corresponding intervals in diastole using the two methods. The peak filling rate (PFR) derived from gated SPET correlated with the Doppler peak velocity of the early transmitral flow (E) wave (r=0.65) and deceleration of the E wave (r=0.71). The time to PFR and percent atrial contribution to LV filling from gated SPET correlated excellently with the Doppler LV isovolumic relaxation time (r=0.93) and the E/A ratio (r=–0.85), respectively. There was a significant linear correlation in all the intervals from the R wave to the presumed corresponding diastolic points. The point of PFR in gated SPET and the peak of the E wave in Doppler echocardiography generally coincided. The onset of filling in gated SPET tended to be closer to the second heart sound than the start of the E wave in Doppler echocardiography. We conclude that gated SPET permits the assessment of not only myocardial perfusion and LV systolic function but also diastolic function, although there may be some errors in detection of the precise beginning of LV filling.     

Multicenter intercomparison assessment of consistency of left ventricular function from a gated cardiac SPECT phantom

Background  A multicenter intercomparison assessment was made of the variation in left ventricular (LV) volumes and ejection fractions (EFs) obtained from gated myocardial perfusion single photon emission computed tomography (SPECT) of the 3-dimensional AGATE (Amsterdam gated) cardiac phantom. Methods and Results  The phantom was configured to produce 3 different standard end-systolic volume and end-diastolic volume combinations (50 mL and 120 mL, 90 mL and 160 mL, and 120 mL and 190 mL) with corresponding EF (58%, 44%, and 37%). Quantitative gated myocardial perfusion SPECT was performed with 39 SPECT systems in 35 departments. In the multicenter study, for all 3 filling conditions, a wide range of results was obtained. The EF was overestimated (by 1% to 15%), and both the end-systolic volume and end-diastolic volume were underestimated (by 1 to 65 mL). The extent of overestimation of EF was related to the extent of underestimation of the volumes and was independent of filling condition. The trend in error per center was comparable for all 3 filling conditions. Acquisition time per projection was the only independent predictor of the difference between measured and expected EF (P = .0001). Conclusions  Care should be taken before extrapolation of published and accepted cutoff values for LV EF and volumes in clinical decision making. Results should be validated in each center and monitored for accuracy and consistency over time.     

Comparison of exercise and pharmacological stress gated SPECT in detecting transient left ventricular dysfunction

OBJECTIVE: Transient left ventricular contractile dysfunction (TLVD) is observed owing to post-exercise stunning in patients with coronary artery disease (CAD). Pharmacological stimulation differs from exercise stress because it does not cause demand ischemia. The aim of this study was to determine whether TLVD could also be seen after pharmacological stress (dipyridamole). METHODS: Of the patients in whom gated single-photon emission computed tomography (GSPECT) was performed in our institution from January 2004 to April 2007, 439 subjects with known or suspected CAD were included in the study. GSPECT was performed for all patients following exercise (group I, n = 220) or pharmacological stress (group II, n = 219) according to a 2-day (stress-rest) protocol after injection of Tc-99m methoxyisobutyl-isonitrile (MIBI). Stress, rest, and difference (stress-rest value) left ventricular ejection fractions (SLVEF, RLVEF, and DLVEF) and transient ischemic dilatation (TID) ratio were derived automatically. Summed stress score, summed rest score, and summed difference score (SDS) for myocardial perfusion were calculated using a 20-segment model and a five-point scoring system. An SDS > 3 was considered as ischemic. On the basis of the perfusion findings, patients were subdivided into a normal (group A, n = 216) and ischemia group (group B, n = 223). DLVEF and perfusion scores of all groups were compared. Relationships between DLVEF and perfusion, and between TID ratio and DLVEF were also evaluated. RESULTS: Stress-induced ischemia was observed in 223 of 439 patients (50.8%). In group A, the difference between stress and rest LVEF values was not significant (P = 0.670 and P = 0.200 for groups IA and IIA, respectively). However, LVEF was significantly decreased after stress compared with rest values for group B (P < 0.0001 for groups IB and IIB). TLVD (< or =-5% for DLVEF) was observed in 20 of 216 (9%) and 81 of 223 subjects (36%) in patients in groups A and B, respectively (P < 0.0001). In group I, we found TLVD in 46 of 119 (39%) and 12 of 101 (12%) subjects, in patients with and without ischemia, respectively (P < 0.0001). On the other hand, in group II, TLVD was detected in 35 of 104 (34%) and 8 of 115 (7%) patients with and without ischemia, respectively (P < 0.0001). And also, we found significant good correlations between TID ratios and DLVEF values in four subgroups (r = -0.55, r = -0.62, r = -0.59, and r = -0.41; for groups IA, IB, IIA, and IIB, respectively, P < 0.0001 for all). CONCLUSIONS: Dipyridamole is believed to be less likely than exercise to induce ischemia. However, in this study, TLVD after stress was observed following not only exercise but also pharmacological stress, consistent with ischemia.     

SPECT versus planar gated blood pool imaging for left ventricular evaluation

Background  We developed a new segmentation algorithm based on the invariance of the laplacian (IL) to compute volumes and ejection fractions and compared these results with planar analysis and gradients by use of a standard algorithm (QBS). Methods and Results  Planar and single photon emission computed tomography blood pool acquisition was performed in 202 patients. Planar left ventricular ejection fraction (LVEF) was used as the gold standard, and single photon emission computed tomography images were processed by both 3-dimensional (3D) methods. Correlations between each 3D algorithm and planar methodology were as follows:r=0.77 for QBS andr=0.84 for IL. Mean LVEFs were 32.72%±13.05% for the planar method, 32.32%±15.98% for QBS, and 31.93%±13.44% for IL (P=.16). Bland-Altman analysis closely demonstrated negligible systematic bias for both 3D methods. Standard errors of bias were comparable between methods (9.36% for QBS and 7.44% for IL,P=.48). Linear regression of the Bland-Altman bias revealed a slope significantly different from 0 for the QBS method (0.22±0.048,P<.0001) but not for IL (−0.032±0.0044,P=.47). Conclusion  The new segmentation algorithm provides comparable results to QBS and planar analysis. However, with QBS, the difference in LVEF was correlated with the magnitude of LVEF, which was not found with the new algorithm.     

Assessment of global and regional left ventricular function and volumes with 64-slice MSCT: A comparison with 2D echocardiography

Background  In patients with coronary artery disease (CAD), LV function and volumes are important parameters for long-term prognosis. Multislice computed tomography (MSCT) allows noninvasive assessment of the coronary arteries, but the accuracy of 64-slice MSCT for the assessment of left ventricular (LV) volumes and function is unknown. Methods and Results  A head-to-head comparison between 64-slice MSCT and 2-dimensional (2D) echocardiography was performed in 40 patients with known or suspected CAD. The LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV) were determined and the LV ejection fraction (LVEF) was derived. Regional wall motion was assessed visually using a 17-segment model. A 3-point scoring system was used to assign to each segment a wall motion score: 1 = normokinesia, 2 = hypokinesia, 3 = akinesia or dyskinesia. Two-dimensional echocardiography served as the gold standard. MSCT agreed well with 2D echocardiography for assessment of LVEDV (r = 0.97; p < .0001) and LVESV (r = 0.98; p < .0001). An excellent correlation between MSCT and 2D echocardiography was shown for the evaluation of LVEF (r = 0.91; p < .0001). Agreement for the assessment of regional wall motion was excellent (96%, κ = 0.82). Conclusions  An accurate assessment of global and regional LV function and volumes is feasible with 64-slice MSCT. This work was supported by The Netherlands Heart Foundation, The Hague, The Netherlands, grant numbers 2002B105 (J.D.S.) and 2001D032 (J.W.J.).     

Accuracy of the automated assessment of left ventricular function with gated perfusion SPECT in the presence of perfusion defects and left ventricular dysfunction: Correlation with equilibrium radionuclide ventriculography and echocardiography

BACKGROUND: Gated single photon emission computed tomography (SPECT) with automated methods allows the quantitative assessment of left ventricular function and perfusion; however, its accuracy must be defined for patients with large earlier infarctions and severe rest perfusion defects, in whom the estimation of endocardial and epicardial borders might be more difficult, even with automated edge-detection techniques. METHODS AND RESULTS: We prospectively compared the automated measurements of left ventricular ejection fraction (LVEF) and volumes from rest-injected gated Technetium 99m (Tc99m) perfusion SPECT with equilibrium radionuclide angiocardiography (ERNA) in 62 patients and the assessment of regional function with echocardiography in 22 patients. Forty-six patients had an earlier myocardial infarction (mean defect size, 34% of left ventricle; SD, 12.7%; range, 8% to 56%); 27 patients had large defects (> or = 20% of left ventricle; LVEF range, 8% to 75%). LVEF, as determined with Cedars-Sinai software (quantitative gated SPECT), correlated well with ERNA (r = 0.941; y = 1.003x + 1.15; P<.0001; SE of the estimate = 6.3%; mean difference -1.3% for LVEF) in the entire study population and in the subgroups of patients with an earlier infarction, severe defects, and large infarctions (> or = 20% of the left ventricle). A correlation existed between gated SPECT and ERNA volumes (r = 0.882, y = 1.040x - 14.7, P<.0001 for end-diastolic volume; r = 0.954, y = 1.147x - 13.9, P<.0001 for end-systolic volumes with the count-ratio technique), but with wider limits of agreement. The exact segmental score agreement between gated SPECT and echocardiography for regional function was 79.8% (281 of 352, kappa = 0.682). CONCLUSIONS: Automated gated SPECT provides an accurate assessment of ejection fraction and regional function, even in the presence of an earlier myocardial infarction with large perfusion defects and significant left ventricular dysfunction.     

Relationship between left ventricular function and wall motion synchrony in heart failure assessed by ECG-gated myocardial perfusion SPECT

Objective  To confirm the relationship between left ventricular (LV) function and wall motion synchrony, and to identify the difference of synchrony between an ischemic heart disease (IHD) patient group and other heart disease (OHD) patient group among classified groups in heart failure, systolic, and diastolic parameters were compared using electrocardiograph-gated single-photon emission computed tomography. Methods and results  Twenty IHD and 30 OHD patient groups, comprised New York Heart Association functional class I–III (IHD1-3 and OHD1-3), and 15 controls were examined. The LV functions (ejection fraction, EF; peak-filling rate, PFR) and synchrony, which was estimated from the time lag between the earliest and latest regional systolic or diastolic temporal parameters (maximum difference of regional time to end-systole, MD-TES, or maximum difference of regional time to peak filling, MD-TPF), were compared. The LV function correlated with its synchrony in IHD and OHD (EF vs. MD-TES: r = −0.86, P = 1.3 × 10⁻⁶ in IHD and r = −0.69, P = 2.8 × 10⁻⁵ in OHD. PFR versus MD-TPF: r = −0.67, P < 0.002 in IHD and r = −0.63, P < 0.0002 in OHD). Dyssynchronous normal EF was observed in three IHD (15%) and six OHD (20%). Dyssynchronous normal PFR was observed in six IHD (30%) and six OHD (20%). MD-TES was significantly smaller in control group (CG) than in IHD3 and OHD3 (P < 0.005), and in IHD1 than in IHD3 and OHD3 (P < 0.05). MD-TPF was significantly smaller in CG than in IHD2, IHD3, and OHD3 (P < 0.05). However, there was no significant difference between LV synchrony in IHD and OHD, or among LV synchrony of the same functional classes between these two groups. Conclusions  This study confirms that LV function is correlated with wall motion synchrony. No statistically significant difference was confirmed in wall motion synchrony between IHD and OHD. However, dyssynchrony appears in the patients without apparent global LV dysfunction. This feature may facilitate identification of synchronous disorder in HF patients with preserved global LV function. It is expected that detection of such a disorder may lead to the initiation of appropriate treatments for early stage HF and prevent its progression.     

Assessment of global and regional left ventricular function using 64-slice multislice computed tomography and 2D echocardiography: a comparison with cardiac magnetic resonance

OBJECTIVES: To compare the assessment of global and regional left ventricular (LV) function using 64-slice multislice computed tomography (MSCT), 2D echocardiography (2DE) and cardiac magnetic resonance (CMR). METHODS: Thirty-two consecutive patients (mean age, 56.5+/-9.7 years) referred for evaluation of coronary artery using 64-slice MSCT also underwent 2DE and CMR within 48h. The global left ventricular function which include left ventricular ejection fraction (LVEF), left ventricular end diastolic volume (LVdV) and left ventricular end systolic volume (LVsV) were determine using the three modalities. Regional wall motion (RWM) was assessed visually in all three modalities. The CMR served as the gold standard for the comparison between 64-slice MSCT with CMR and 2DE with CMR. Statistical analysis included Pearson correlation coefficient, Bland-Altman plots and kappa-statistics. RESULTS: The 64-slice MSCT agreed well with CMR for assessment of LVEF (r=0.92; p<0.0001), LVdV (r=0.98; p<0.0001) and LVsV (r=0.98; p<0.0001). In comparison with 64-slice MSCT, 2DE showed moderate correlation with CMR for the assessment of LVEF (r=0.84; p<0.0001), LVdV (r=0.83; p<0.0001) and LVsV (r=0.80; p<0.0001). However in RWM analysis, 2DE showed better accuracy than 64-slice MSCT (94.3% versus 82.4%) and closer agreement (kappa=0.89 versus 0.63) with CMR. CONCLUSION: 64-Slice MSCT correlates strongly with CMR in global LV function however in regional LV function 2DE showed better agreement with CMR than 64-slice MSCT.     

多层螺旋CT评估左心室功能的应用进展

左心室功能评估对心脏疾病的诊断、风险分层、治疗及预后分析具有重要意义。心脏CT血管成像(CCTA)作为一种无创性成像技术,目前在心脏疾病的诊断中发挥着越来越重要的作用,它既可评估冠状动脉狭窄,也能获取左心室容积和功能方面的信息。64层及以上的多层螺旋CT(MSCT)可一站式评价冠状动脉和左心室功能,无需对比剂和辐射的重复暴露,心功能分析结果可重复性高,具有较高的临床应用价值。     

Left ventricular ejection fraction and volumes from gated blood pool tomography: Comparison between two automatic algorithms that work in three-dimensional space

BACKGROUND: Two different algorithms, which are fast and automatic and which operate in 3-dimensional space, were compared in the same group of patients to compute left ventricular ejection fraction (LVEF) and volumes from gated blood pool tomography. One method, developed at Cedars-Sinai Medical Center (CS), was dependent on surface detection, whereas the other method, developed at the Free University of Brussels (UB), used image segmentation. METHODS AND RESULTS: Gated blood pool tomograms were acquired in 92 consecutive patients after injection of 740 MBq of technetium 99m-labeled human serum albumin. After reconstruction and reorientation according to the left ventricular long axis, LVEF and left ventricular volumes were measured with the CS and UB algorithms. Measurements of LVEF were validated against planar radionuclide angiocardiography (PRNA) results. The success rates of the algorithms were 87% for CS and 97% for UB. Agreement between LVEF measured with CS and UB (LVEF(CS) = 0.91. LVEF(UB) - 0.85; r = 0.87) and between LVEF measured with CS and PRNA (LVEF(CS) = 1.04. LVEF(PRNA) - 4.75; r = 0.80) and UB and PRNA (LVEF(UB) = 0.98. LVEF(PRNA) + 4.42; r = 0.82) was good. For left ventricular volumes, linear regression analysis showed good correlation between both methods with regard to end-diastolic volumes (r = 0.81) and end-systolic volumes (r = 0.91). On average, end-diastolic volumes were similar and end-systolic volumes were slightly higher with CS than with UB. Consequently, significantly lower LVEFs were observed with CS than with UB. CONCLUSIONS: Good correlation was observed between CS and UB for both left ventricular volumes and ejection fraction. In addition, measurements of LVEF obtained with both algorithms correlated fairly well with those obtained from conventional PRNA over a wide range of values.     

Quantification of global left ventricular function: comparison of multidetector computed tomography and magnetic resonance imaging. a meta-analysis and review of the current literature

Cardiac morbidity and mortality are closely related to cardiac volumes and global left ventricular (LV) function, expressed as left ventricular ejection fraction. Accurate assessment of these parameters is required for the prediction of prognosis in individual patients as well as in entire cohorts. The current standard of reference for left ventricular function is analysis by short-axis magnetic resonance imaging. In recent years, major extensive technological improvements have been achieved in computed tomography. The most marked development has been the introduction of the multidetector CT (MDCT), which has significantly improved temporal and spatial resolutions. In order to assess the current status of MDCT for analysis of LV function, the current available literature on this subject was reviewed. The data presented in this review indicate that the global left ventricular functional parameters measured by contemporary multi-detector row systems combined with adequate reconstruction algorithms and post-processing tools show a narrow diagnostic window and are interchangeable with those obtained by MRI.     

Differences in left ventricular ejection fraction and volumes measured at rest and poststress by gated sestamibi SPECT

Background  Some studies suggested that the poststress left ventricle ejection fraction (LV EF) is lower than rest LV EF in patients with stress-induced ischemia. Methods and Results  By using a 2-day protocol and 30 mCi Tc-99m sestamibi, LV EF, end-systolic volume (ESV), and end-diastolic volume (EDV) were measured with gated SPECT. Of 99 eligible patients, 91 had technically adequate studies. Poststress LV EF minus rest LV EF was defined as ΔLV EF. ΔEDV and ΔESV were similarly defined. Rest and poststress LV EF (r = 0.89), EDV (r = 0.78), and ESV (r = 0.93) were highly correlated (P <.001). Rest LV EF, EDV, and ESV were not significantly different between patients with and without stress-induced ischemia. ΔLV EF was significantly lower in patients with stress-induced ischemia (-3.5% ± 4.5% vs -1.1% ± 4.7%, P ± .02). Mean LV EF poststress in ischemic patients was 55.0% ± 10.5% vs 61.2% ± 10.0% in nonischemic patients (P = .008). However, only 1 patient (3%) with ischemia had ΔLV EF that exceeded the 95% confidence limit of ΔLV EF for normal patients. Ischemia was significantly associated with increased ΔEDV and ΔESV (P <.01). Conclusions  Stress-induced ischemia is associated with poststress reduction in LV EF and increased poststress EDV and ESV. However, the effect of ischemia on the difference between poststress and rest EF measurements is modest and rarely exceeds the confidence limits in normal patients undergoing 2-day protocols. In most patients, poststress LV EF is an accurate reflection of rest LV EF.     

Comparison of gated blood pool SPECT and spiral multidetector computed tomography in the assessment of right ventricular functional parameters: validation with first-pass radionuclide angiography

Objective The aim of this study was to compare gated blood pool single photon emission computed tomography (SPECT) (GBPS) and multidetector row computed tomography (MDCT) for the determination of right ventricular ejection fraction (RVEF) and right ventricular volumes (RVV) and to compare first-pass radionuclide angiography (FP-RNA) as the gold standard. Methods Twenty consecutive patients (11 men, 9 women) referred for MDCT for the evaluation of the presence of coronary artery disease underwent FP-RNA and GBPS. Results The mean right ventricular end-diastolic volume (EDV) calculated with GBPS revealed a statistically significant lower value than that of MDCT. The mean right ventricular end-systolic volume (ESV) calculated with GBPS was also lower than that of MDCT. A comparison of right ventricular EDV from GBPS and MDCT yielded a correlation coefficient of 0.5972. Right ventricular ESV between GBPS and MDCT showed a correlation coefficient of 0.5650. The mean RVEFs calculated with FP-RNA (39.8% ± 4.0%), GBPS (43.7% ± 6.9%), and MDCT (40.4% ± 7.7%) showed no statistical differences (Kruskal–Wallis statistics 4.538, P = 0.1034). A comparison of RVEFs from FP-RNA and GBPS yielded a correlation coefficient of 0.7251; RVEFs between FP-RNA and MDCT showed a correlation coefficient of 0.6166 and between GBPS and MDCT showed a correlation coefficient of 0.6367. Conclusion The RVEF, EDV, and ESV calculated by GBPS had good correlation with those obtained with MDCT. In addition, there were no statistical differences of RVEF calculated from FP-RNA, GBPS, and MDCT. However, with regard to RVV, EDV and ESV from GBPS revealed statistically significantly lower values than those of MDCT. Although reasonable correlations among these modalities were obtained, the agreement among these three modalities was not good enough for interchangeable use in the clinical setting. Also, these results should be confirmed in patients with cardiac diseases in future larger population-based studies. The first two authors contributed equally to this study     

Comparison between ECTb and QGS for assessment of left ventricular function from gated myocardial perfusion SPECT

BACKGROUND: The most widely distributed software packages to compute left ventricular (LV) volume and ejection fraction (EF) from gated perfusion tomograms are QGS and the Emory Cardiac Toolbox (ECTb). Because LV modeling and time sampling differ between the algorithms, it is necessary to document relationships between values produced by them and to establish normal limits individually for each software package in order to interpret results obtained for individual patients. METHODS AND RESULTS: Gated single photon emission computed tomography technetium 99m sestamibi myocardial perfusion studies were collected and analyzed for 246 patients evaluated for coronary artery disease. QGS and ECTb values of ejection fraction (EF), end-diastolic volume (EDV), and end-systolic volume were found to correlate linearly (r = 0.90, 0.91, and 0.94, respectively), but EF and EDV were significantly lower for QGS than with ECTb (53% +/- 13% vs 61% +/- 13 and 102 +/- 45 mL vs 114 +/- 50 mL, respectively). To compare calculations for healthy subjects between the two software packages, data were also selected for 50 other patients at low likelihood for coronary artery disease, for whom EF and EDV were significantly lower for QGS compared with ECTb (62% +/- 9% vs 67% +/- 8% and 84 +/- 26 mL vs 105 +/- 33 mL, respectively). The ECTb lower limit was 51% for EF and the upper limits were 171 mL for EDV and 59 mL/m(2) for mass-indexed EDV, compared with limits of 44%, 137 mL, and 47 mL/m(2) for QGS. CONCLUSIONS: Although correlations were strong between the two methods of computing LV functional values, statistical scatter was substantial and significant biases and trends observed. Therefore, when both software packages are used at the same site, it will be important to take these differences into consideration and to apply normal limits specific to each set of algorithms.     

MSCT与超声心动图评价成人左心室整体收缩功能的对比研究

目的 与超声心动图对比,探讨MSCT评估左室整体收缩功能与超声心动图的相关性,评价MSCT测量左室整体收缩功能的可行性及准确性.方法 回顾性分析MSCT冠状动脉CTA检查的50例患者的资料,以10％ R-R间期间隔重建图像,测定出左心室舒张末期容积(EDV)、收缩末期容积(ESV)、每搏输出量(SV)、左室射血分数(EF),同时进行超声心动图检查,与超声心动图所测得的相应指标进行相关性分析.结果 10％R-R间期间隔测定的心功能指标与超声心动图检查的各项指标的相关性很高,r在(0.70～0.96)之间,EDV、ESV、SV值:MSCT＞超声心动图,EF值:MSCT≤超声心动图.结论 MSCT冠状动脉造影检查所获得的整体心功能指标数据较准确、可靠,具有较高的临床应用价值,临床可应用10％R-R间期间隔重建图像测定心功能,相对简便快捷.     

Sixty-four-slice multidetector computed tomography for preoperative evaluation of left ventricular function and mass in patients with mitral regurgitation: comparison with magnetic resonance imaging and echocardiography

Quantitative values of left ventricular (LV) function and muscle mass in patients with mitral regurgitation are independent predictors of cardiac morbidity and mortality. The aim of this study was to prospectively evaluate whether 64-MDCT can assess the LV function in patients with mitral regurgitation with high accuracy when compared with the MRI and echocardiography results. Fifty-one patients with mitral regurgitation underwent retrospectively ECG-gated 64-MDCT, echocardiography, and MRI for assessing the global ventricular function. End-diastolic and end-systolic volume, stroke volume, ejection fraction, and mass were measured on 64-MDCT and echocardiography, and compared with the results measured on MRI which served as the reference standard. Intertechnique agreement was tested by using Pearson’s correlation and Bland–Altman analyses. No significant differences were revealed in calculated LV function and mass between the 64-MDCT and MRI (paired t test, p = 0.07–0.53). Pearson’s correlation analysis showed the functional parameters and mass correlated closely between the 64-MDCT and MRI (r = 0.89–0.96, p < 0.001). When compared with MRI, echocardiography underestimated the volumetric parameters of LV (paired t test, p = 0.0003–0.004), but significantly overestimated the EF values (p = 0.003), and moderate correlations of functional parameters were obtained (r = 0.78, 0.60, 0.81, and 0.62, respectively). ECG-gated 64-MDCT allows for accurate and reliable assessment of LV function in patients with mitral regurgitation, whereas LV volumes measured by two-dimensional echocardiography were underestimated and the ejection fraction was overestimated when compared with those achieved by using MRI.     

Thallium-201 gated single-photon emission tomography for the assessment of left ventricular ejection fraction and regional wall motion abnormalities in comparison with two-dimensional echocardiography

Simultaneous assessment of myocardial perfusion and function by gated single-photon emission tomography (GS) after a single tracer injection provides incremental information and is feasible with technetium-99m sestamibi. The present study validated the use of GS with thallium-201 for the assessment of left ventricular ejection fraction (LVEF) and regional wall motion by comparison with two-dimensional (2D) echocardiography (echo), which has not been done before. After injection of 111 MBq ²⁰¹Tl at peak bicycle exercise (n=55) or pharmacological stress (n=17), GS was acquired 15 (post stress) and 120 min post injection (rest) on a double-head camera. An automatic algorithm (QGS) was used for processing. Echo (Acuson Sequoia C256) was performed immediately after rest GS. LVEFs assessed by GS and echo were correlated. The overall and segmental sensitivity and specificity of GS for the detection of regional wall motion abnormalities (WMAs) were calculated, echo serving as the gold standard. Perfusion abnormalities were scored. The success rate of the automatic algorithm was 100%, and visually assessed image quality was good to excellent in 88% of cases. Post-stress and rest LVEF as assessed by GS were highly correlated (r=0.91). Good correlations were obtained between post-stress LVEF (GS) and rest LVEF (echo) and between rest LVEF (GS) and rest LVEF (echo) (r=0.76 and 0.86 respectively). In patients with a reduced LVEF of less than 50% (n=23), these correlations were even better (r=0.84 and 0.89 respectively). Regional wall motion abnormalities (WMAs) were identified by GS with high sensitivity and specificity (88%–100% and 82%–98% respectively) and were directly related to the extent and severity of stress as well as of resting perfusion defects. It is concluded that GS with ²⁰¹Tl is a feasible and reliable tool for the evaluation of patients with compromised left ventricular function in the context of coronary artery disease, and thus improves diagnosis and prognostic stratification. Regional WMAs were identified with high diagnostic accuracy and the method may prove helpful for the detection of myocardial viability. Received 20 February and in revised form 12 June 1999     

Congenital left ventricular wall abnormalities in adults detected by gated cardiac multidetector computed tomography: Clefts, aneurysms, diverticula and terminology problems

Objectives

Our aim was to evaluate congenital left ventricular wall abnormalities (clefts, aneurysms and diverticula), describe and illustrate imaging features, discuss terminology problems and determine their prevalence detected by cardiac CT in a single center.

Materials and methods

Coronary CT angiography images of 2093 adult patients were evaluated retrospectively in order to determine congenital left ventricular wall abnormalities.

Results

The incidence of left ventricular clefts (LVC) was 6.7% (141 patients) and statistically signi?cant difference was not detected between the sexes regarding LVC (P = 0.5). LVCs were single in 65.2% and multiple in 34.8% of patients. They were located at the basal to mid inferoseptal segment of the left ventricle in 55.4%, the basal to mid anteroseptal segment in 24.1%, basal to mid inferior segment in 17% and septal–apical septal segment in 3.5% of cases. The cleft length ranged from 5 to 22 mm (mean 10.5 mm) and they had a narrow connection with the left ventricle (mean 2.5 mm). They were contractile with the left ventricle and obliterated during systole. Congenital left ventricular septal aneurysm that was located just under the aortic valve was detected in two patients (0.1%). No case of congenital left ventricular diverticulum was detected.

Conclusion

Cardiac CT allows us to recognize congenital left ventricular wall abnormalities which have been previously overlooked in adults. LVC is a congenital structural variant of the myocardium, is seen more frequently than previously reported and should be differentiated from aneurysm and diverticulum for possible catastrophic complications of the latter two.