Transient ischemic dilatation ratio derived from myocardial perfusion scintigraphy: What are we looking at?

Background  

Elevated transient ischemic dilatation (TID) ratio during myocardial perfusion imaging (MPI) is described as a marker of severe CAD, even in acquisitions with normal perfusion. This was initiated to explore the effects of stressor type on the TID. Additionally the relation between the TID and other functional parameters, such as end diastolic volume (EDV), end systolic volume (ESV), and left ventricle ejection fraction (LVEF), heart rate (HR), and severity of ischemia, was evaluated.     

Prognostic value of <Superscript>18</Superscript>F-FDG PET image-based parameters in oesophageal cancer and impact of tumour delineation methodology

Purpose  

¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) image-derived parameters, such as standardized uptake value (SUV), functional tumour length (TL) and tumour volume (TV) or total lesion glycolysis (TLG), may be useful for determining prognosis in patients with oesophageal carcinoma. The objectives of this work were to investigate the prognostic value of these indices in oesophageal cancer patients undergoing combined chemoradiotherapy treatment and the impact of TV delineation strategies.     

Gated blood-pool SPECT versus cardiac magnetic resonance imaging for the assessment of left ventricular volumes and ejection fraction

Background  

We evaluated the accuracy of planar radionuclide angiography and different count-based and space-based electrocardiogram (ECG)-gated blood-pool single-photon emission computed tomography (GBPS) algorithms for assessment of left ventricular end-diastolic volume (LVEDV), end-systolic volume (LVESV), and ejection fraction (LVEF) compared with the gold standard of cardiac magnetic resonance imaging (cMRI). The goal is to assess the accuracy of a recently developed GBPS algorithm.     

Myocardial washout of <Superscript>99m</Superscript>Tc-tetrofosmin and response to steroid therapy in patients with cardiac sarcoidosis

Objective  

Early diagnosis and initiating treatment of cardiac sarcoidosis are essential because cardiac involvement is an important prognostic factor. Although there are many reports on the diagnosis of cardiac sarcoidosis, the literature on predicting the efficacy of steroid therapy is very limited. The purposes of this study were to investigate the myocardial washout of ^99mTc-tetrofosmin (TF), and to evaluate the predictability of left ventricular (LV) functional recovery after steroid therapy in patients with cardiac sarcoidosis.     

PET functional volume delineation: a robustness and repeatability study

Purpose  

Current state-of-the-art algorithms for functional uptake volume segmentation in PET imaging consist of threshold-based approaches, whose parameters often require specific optimization for a given scanner and associated reconstruction algorithms. Different advanced image segmentation approaches previously proposed and extensively validated, such as among others fuzzy C-means (FCM) clustering, or fuzzy locally adaptive bayesian (FLAB) algorithm have the potential to improve the robustness of functional uptake volume measurements. The objective of this study was to investigate robustness and repeatability with respect to various scanner models, reconstruction algorithms and acquisition conditions.     

Fully automatic geometry planning for cardiac MR imaging and reproducibility of functional cardiac parameters

Purpose:

To establish operator‐independent, fully automated planning of standard cardiac geometries and to determine the impact on interstudy reproducibility of cardiac functional parameters.

Materials and Methods:

Cardiac MR imaging was done in 50 patients referred for left‐ventricular function assessment. In all patients, first standard manual planning was performed followed by automatic planning (AUTO1) and repeat automatic planning (AUTO2) after repositioning the patient to investigate interstudy reproducibility. Cardiac functional parameters were assessed and cine scans were visually graded on a 4‐point scale from nondiagnostic to excellent.

Results:

Overall success rate of AUTO was 94% with good to excellent geometry planning in >94% of cine standard views. Comparing manual versus fully automated planning, a high agreement of cardiac functional parameters (Lin's concordance correlation coefficient, 0.91 to 0.99) with minimal percent bias (0.24 to 3.84%) was found. In addition, a high interstudy reproducibility of automatic planning was demonstrated (Lin's concordance correlation coefficient, 0.89 to 0.99; percent bias, 0.38 to 5.04%; precision, 3.46 to 9.09%).

Conclusion:

Fully automated planning of cardiac geometries could reliably be performed in patients showing a variety of cardiovascular pathologies. Standard cardiac geometries were precisely replicated and functional parameters were highly accurate. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.     

Cardiac-sparing radiotherapy for the left breast cancer with deep breath-holding

Purpose  

The aim of this study was to evaluate the effect of decreasing the irradiated cardiac volume in breast-conserving therapy (BCT) using breath-adapted radiation therapy (BART).     

Role of echocardiography and cardiac MRI in depicting morphological and functional imaging findings useful for diagnosing hypertrophic cardiomyopathy

Purpose

Hypertrophic cardiomyopathy (HCM) is a hereditary disease characterised by primary hypertrophy of the left and/or right ventricle. The reference standard for imaging diagnosis is echocardiography. The aim of our study was to prospectively compare the diagnostic accuracy of echocardiography and cardiac magnetic resonance (MR) imaging in patients with HCM.

Materials and methods

Twenty-two consecutive patients with a known diagnosis of HCM were prospectively evaluated, with echocardiography and cardiac MR imaging performed within 2 weeks of each other (mean interval 7 days, range 2?C14 days). Two experienced radiologists blinded to the previous clinical and imaging findings separately reviewed the images. The following parameters were calculated for both techniques: myocardial mass, wall thickness, end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), systolic anterior motion (SAM) of the mitral valve and degree of myocardial fibrosis (based on the ultrasonic reflectivity at echocardiography and degree of late enhancement at cardiac MR imaging). The statistical correlation was calculated with Student??s t test, Spearman coefficient and Fisher??s exact test. A value of p<0.05 was considered significant.

Results

The diagnosis of HCM was confirmed in all patients with both techniques, with absolute agreement in terms of the site of disease. The mean value of myocardial mass presented a statistically significant difference between the two techniques (114 g, p<0.001). In contrast, a nonsignificant difference between echocardiography and cardiac MR imaging was found for EDV (102 ml vs 111 ml; p=0.31), ESV (30 ml vs 38 ml; p=0.1), EF (74% vs 68%, p=0.5), SAM (p=0.1) and myocardial fibrosis (p=0.15).

Conclusions

Cardiac MR imaging correlates well with echocardiography in defining the morphological and functional parameters useful for the imaging diagnosis of HCM and therefore, in selected cases (poor acoustic window, doubtful echocardiography findings), it may be a valid alternative to echocardiography.     

The agreement of left ventricular function parameters between 99mTc-tetrofosmin gated myocardial SPECT and gated myocardial MRI

Objective

The aim is to compare and evaluate the agreement of quantification of left ventricular functional parameters obtained by two different methods, ^99mTc-tetrofosmin gated myocardial perfusion SPECT (MPS) and cardiac magnetic resonance imaging (CMR).

Methods

Ten healthy male volunteers participated. Gated MPS data were acquired using 32 frames, which were also combined into 16- and 8-frame data set for the investigation. Gated CMR data were acquired using 8, 16 and 32-frame for the different sets. All examinations were conducted in resting and at exercise conditions. Quantitative measurements of end-diastolic volume (EDV), end-systolic volume (ESV), left ventricular ejection fraction (LVEF), peak ejection rate (PER), peak filling rate (PFR) and time to peak filling (TTPF) were done for each study, respectively. Finally, we evaluated the concordance of parameters between gated MPS and gated CMR by % difference and Bland?CAltman plot analysis.

Results

LVEF showed favorable concordance in both rest and exercise conditions (% differences were around 10%). PER, PFR and TTPF also showed good concordances in rest conditions, under 32-frame gated collections particularly (% differences were around 10%). In exercise conditions, although the concordances were relatively good, certain variances were noted (% differences were around 20?C25%). Regarding left ventricular volumes, the concordance were worse in both conditions (% differences were around 30?C40%).

Conclusions

In quantifying of left ventricular function parameter, gated CMR provides similar quantitative values comparing with gated MPS except for ventricular volumes in rest conditions. In contrast, there were certain variations except for LVEF in exercised examinations. When we follow patients by the same cardiac parameters with CMR and MPS, using parameters across the two modalities proved to be possible under rest condition. However, it is limited at exercise condition.     

Cardiovascular MR dobutamine stress in adult tetralogy of Fallot: disparity between CMR volumetry and flow for cardiovascular function

Purpose:

To evaluate the MR agreement of cardiac function parameters between volumetric (cine SSFP) and phase contrast flow (PC‐flow) assessment in patients with repaired tetralogy of Fallot (r‐TOF) and chronic pulmonary regurgitation (PR) at rest and under dobutamine stress (DS‐MR).

Materials and Methods:

We studied 18 patients with r‐TOF and severe chronic PR (34 ± 12.7 years, PR fraction_[flow] 44 ± 15%) by cardiac MR at rest, 10 and 20 μg/kg/min of dobutamine. We compared analogous functional parameters by volumetry and PC‐flow: (i) Systemic output [left ventricle stroke volume (LV_SV) versus aortic forward flow (AO_FF)], (ii) Pulmonary output [right ventricle stroke volume (RV_SV) versus pulmonary forward flow (PA_FF)], (iii) PR volume [(RV_SV‐LV_SV) versus pulmonary backward flow (PA_BF)], (iv) PR fraction [(RV_SV‐LV_SV/RV_SV) versus (PA_BF/PA_FF)].

Results:

We found excellent Bland‐Altman agreement (mean difference ± limits of agreement, mL/beat/m²) at rest for both the systemic (?0.8 ± 5.7) and pulmonary strokes volumes (?0.1 ± 7.6), which slightly deteriorates during DS‐MR. The PR volume showed acceptable agreement at rest (?3.6 ± 15.1), but also further deteriorated during stress (5.4 ± 24). In contrast, the PR fraction showed poor agreement equally at rest (?5.6 ± 22.8) and DS‐MR (3.2 ± 19.2).

Conclusion:

In r‐TOF with chronic PR, analogous functional parameters should not be used interchangeably between volumetric and PC‐flow assessment during DS‐MR evaluation. J. Magn. Reson. Imaging 2011;33:1341–1350. © 2011 Wiley‐Liss, Inc.

     

The variable functional effects of the pacing site in normal and scarred ventricles

Background  

The pacing site has been shown to influence functional improvement with cardiac resynchronization therapy. We evaluated the effects of the pacing site on left ventricular (LV) function in an animal model.     

Lung volumes, ventricular function and pulmonary arterial flow in children operated on for left-sided congenital diaphragmatic hernia: long-term results

Objectives  

To compare MRI-based functional pulmonary and cardiac measurements in the long-term follow-up of children operated on for left-sided congenital diaphragmatic hernia (CDH) with age- and body size-matched healthy controls.     

Measurements of diagnostic examination performance and correlation analysis using microvascular leakage,cerebral blood volume,and blood flow derived from 3T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in glial tumor grading

Introduction  

To assess the diagnostic accuracy of microvascular leakage (MVL), cerebral blood volume (CBV) and blood flow (CBF) values derived from dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MR imaging) for grading of cerebral glial tumors, and to estimate the correlation between vascular permeability/perfusion parameters and tumor grades.     

Planar radionuclide angiography with a dedicated cardiac SPECT camera

Background

We compared a dedicated cardiac camera with a traditional system for left ventricular (LV) functional measurements using gated blood-pool imaging.

Methods

24-frame gated planar images were obtained from 48 patients in an LAO orientation for 6M counts/view on a standard gamma camera. Immediately thereafter, 24-frame ECG-gated data were obtained for 8 minutes on a dedicated cardiac SPECT camera. The gated SPECT image volumes were iteratively reconstructed and then transferred offline. In-house software was used to reproject the images into a 24-frame gated planar format. Both the original and the reprojected gated planar datasets were analyzed using semiautomated software to determine ejection fraction (EF), ventricular volume (end diastolic volume, EDV), peak ejection rate (PER), and peak filling rate (PFR).

Results

The difference in EF values averaged 0.4% ± 4.4%. The correlation in EF was r ≥ 0.94 (P < .01) with a linear regression slope of 0.98. Correlation of the EDV was r ≥ 0.86 (P < .01), but the volumes from the dedicated cardiac camera were smaller (linear regression slope was 0.6). Correlation of PFR and PER were r = 0.91 and r ≥ 0.83, respectively (P < .01 for both).

Conclusions

Reprojection of 24-frame gated blood-pool SPECT images is an effective means of obtaining LV functional measurements with a dedicated cardiac SPECT camera using standard 2D-planar analysis tools.     

The role of serial FDG PET for assessing therapeutic response in patients with cardiac sarcoidosis

Background

The purpose of this study was to determine the feasibility of serial quantitative 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET) to monitor the response of cardiac sarcoidosis to treatment.

Methods and Results

A total of 38 PET scan intervals (54 PET scans) were obtained in 16 patients with cardiac sarcoidosis who underwent serial FDG PET during treatment. FDG-avid lesions of the heart were interpreted quantitatively using 4 PET parameters: maximum standardized uptake value (SUVmax), partial volume corrected mean standardized uptake value (SUVmean), partial volume corrected metabolic volume product (MVP), and global metabolic volume product (gMVP). Clinical response to treatment (improved, stable, or progressive disease) was evaluated by clinical symptoms, NYHA class, and EKG in all the patients. SUVmax, SUVmean, MVP, and gMVP had significantly decreased value on repeat PET in patients who were either stable or showed clinical improvement between two serial PET scans, while none of them had significant change on repeat PET in patients who were clinically worse. Correlation analysis between PET findings and clinical assessment revealed that the changes of SUVmax and SUVmean on repeat PET were negatively correlated with patient’s clinical outcome.

Conclusion

Our results indicated that serial FDG PET is feasible to determine the extent of disease activity and to quantitatively assess the response of cardiac sarcoidosis to therapy.

     

Clinical usefulness of a novel program “Heart Function View” for evaluating cardiac function from gated myocardial perfusion SPECT

Objective

To investigate clinical usefulness of a novel program “Heart Function View (HFV)” for evaluating left ventricular (LV) function from myocardial perfusion SPECT (MPS), we compared LV functional parameters (F(x)) calculated by HFV with those obtained by the other similar programs QGS and cardioGRAF or by ultrasound echocardiography (UCG) and examined their correlations with clinical markers of heart failure: plasma BNP concentrations (BNPs) and exercise capacity.

Methods

Studied patients (n = 60) underwent technetium-99m tetrofosmin quantitative gated MPS including treadmill exercise for examining heart disease. Myocardial stress images were acquired 30 min after the first tracer injection during maximal exercise. Three hours later, the second tracer was injected, and resting images were acquired. LV systolic F(x) [ejection fraction (EF), peak ejection rate (PER)] and diastolic F(x) [first third filling fraction (1/3FF), first third filling rate (1/3FR), peak filling rate (PFR), time to PFR (TPF)] were analyzed, and phase standard deviation (SD) and histogram bandwidth were obtained by phase analysis.

Results

LV end-diastolic volume (EDV), end-systolic volume (ESV) and EF obtained from HFV were well correlated with those from QGS, cardioGRAF and UCG. A diastolic parameter Doppler E/e′ from UCG was significantly with PFR from HFV. There were good correlations between LVEDV, LVESV, LVEF, PER, PFR, 1/3FR, TPF and 1/3FF from HFV and those from cardioGRAF. LVEF, PER, 1/3FR, and PFR were significantly correlated with plasma BNP concentrations. In patients with non-ischemic heart disease (n = 42), phase SD and histogram bandwidth were correlated negatively with exercise capacity or PFR.

Conclusions

HFV-derived LVF(x) are correlated with LVF(x) from the other programs or UCG, or with the clinical markers of heart failure and are thus useful in the functional assessment for patients with heart disease.     

Multicontrast late gadolinium enhancement imaging enables viability and wall motion assessment in a single acquisition with reduced scan times

Purpose

To determine the accuracy of multicontrast late enhancement imaging (MCLE) in the assessment of myocardial viability and wall motion compared to the conventional wall motion and viability cardiac magnetic resonance imaging (MRI) pulse sequences.

Materials and Methods

Forty‐one patients with suspected myocardial infarction were studied. Patients underwent assessment of cardiac function with cine steady‐state free‐precession (SSFP), followed by late gadolinium enhancement (LGE) imaging using inversion recovery gradient echo scanning (IR‐GRE) sequence and MCLE. MCLE was compared to cine SSFP in the assessment of wall motion, ejection fraction (EF), left ventricular (LV) mass, LV end‐diastolic volume (EDV), and to IR‐GRE for measuring infarct size.

Results

MCLE, IR‐GRE, and SSFP imaging demonstrated excellent agreement in the assessment of EF, LV infarct size, and LV mass (r > 0.95, P < 0.001 for all measures), as well as in the assessment of wall motion (κ statistic 0.75).

Conclusion

MCLE provided coregistered images for the assessment of viability and wall motion without loss of accuracy in the assessment of quantitative cardiac parameters. MCLE provides accurate quantitative cardiac assessment with reduced scan times compared to the conventional sequences and thus may be used as an alternative to conventional cine SSFP and IR‐GRE imaging. J. Magn. Reson. Imaging 2009;30:771–777. © 2009 Wiley‐Liss, Inc.     

Interassay reproducibility of myocardial perfusion gated SPECT in patients with atrial fibrillation

Aim  

The aim of this study was to assess interassay reproducibility of myocardial perfusion gated-SPECT for calculation of end-diastolic volume (EDV), end-systolic volume (ESV), and left ventricular ejection fraction (LVEF) in patients with atrial fibrillation (AF).     

Functional volumetric analysis of striatum using F-18 FP-CIT PET in patients with idiopathic Parkinson’s disease and normal subjects

Objective

We applied a simple isocontour volume-of-interest (VOI) method to analyze the whole striatum in an F-18 FP-CIT PET image and to investigate the usefulness of the method in differentiating healthy subjects from idiopathic Parkinson’s disease (IPD) patients and the correlation of the value of functional volume parameters with the motor symptoms in patients with IPD.

Methods

Forty-three IPD patients and 23 age-matched healthy controls underwent F-18 FP-CIT PET. Using a dedicated workstation, VOIs for the whole striatum were drawn automatically with the gradient delineation method. The SUVmax, SUVmean, functional volume (FV), striatal volume activity (SVA), striatal-specific binding (SSB), and volume-specific uptake ratio (VSUR) were compared between the IPD patients and the normal subjects. In the IPD patients, the correlation between the clinical factor and the functional parameters was assessed.

Results

The SUVmax, SUVmean, FV, SVA, SSB, and VSUR were significantly lower in the IPD patients than in the normal subjects. In the receiver operating characteristic analysis, those parameters had significant and good-to-excellent accuracy. In the patients with IPD, a moderate negative correlation was revealed between the SUVmax and H&Y stage, the SUVmean and H&Y stage, SVA and H&Y stage, the VSUR and H&Y stage, the FV and bradykinesia, and the SVA and bradykinesia.

Conclusion

The functional volumetric analysis of the striatum based on simple isocontour VOI was a useful method of analyzing the F-18 FP-CIT PET image. Not only can it be easily applied in daily clinical practice, but it can also be used as a clinical parameter to discriminate IPD and to correlate it with the disease severity.

     

Prevalence and functional impact of lipomatous metaplasia in scar tissue following myocardial infarction evaluated by MRI

Objective

To retrospectively assess the prevalence and functional relevance of lipomatous metaplasia (LM) of the left ventricle in patients with chronic ischaemic heart disease (CIHD) using cardiac magnetic resonance imaging (cMRI) with steady state free precession (SSFP) sequences.

Methods

We examined 315 patients (248 male, mean age 63?±?10 years) with a history of CIHD by cMRI. Standard SSFP sequences were applied and results were correlated with findings from cardiac catheterisation and computed tomography. In a subgroup of patients with LM (LM+) the functional results were correlated with patients without LM (LM?) as controls matched for age, body mass index, gender and infarct size.

Results

Of 315 patients, 36 showed LM. LM+ patients showed a higher tendency to develop aneurysms compared with LM? (31% vs. 17%; not significant), but no differences in ejection fraction or volumetric parameters. LM occurred significantly more often in older infarcts and patients with hyperlipoproteinaemia, while other cardiac risk factors or medication did not have a significant influence on the development of LM.

Conclusions

LM is a common finding (11%) in patients with CIHD. LM does not have a significant influence on global cardiac function or ventricular size, but on local function and probably also on the development of left ventricular aneurysms.