A telemonitoring programme in patients with heart failure in France: a cost-utility analysis.

BACKGROUND: Certain telemedicine programmes for heart failure (HF) have been shown to reduce all-cause mortality and heart failure-related hospitalisations, but their cost-effectiveness remains controversial. The SCAD programme is a home-based interactive telemonitoring service for HF, which is one of the largest and longest-running telemonitoring programmes for HF in France. The objective of this cost-utility analysis was to evaluate the cost-effectiveness of the SCAD programme with respect to standard hospital-based care in patients with HF. METHODS: A Markov model simulating hospitalisations and mortality in patients with HF was constructed to estimate outcomes and costs. The model included six distinct health states (three 'not hospitalised' states, two 'hospitalisation for heart failure' states, both depending on the number of previous hospitalisations, and one death state). The model lifetime in the base case was 10 years. Model inputs were based on published literature. Outputs (costs and QALYs) were compared between SCAD participants and standard care. Deterministic and probabilistic sensitivity analyses were performed to assess uncertainty in the input parameters of the model. RESULTS: The number of quality-adjusted life years (QALYs) was 3.75 in the standard care setting and 4.41 in the SCAD setting. This corresponds to a gain in QALYs provided by the SCAD programme of 0.65 over the 10 years lifetime of the model. The estimated total cost was €30,932 in the standard care setting and €35,177 in the SCAD setting, with an incremental cost of €4245. The incremental cost-effectiveness ratio (ICER) for the SCAD programme over standard care was estimated at €4579/QALY. In the deterministic sensitivity analysis, the variables that had the most impact on the ICER were HF management costs. The likelihood of the SCAD programme being considered cost-effective was 90% at a willingness-to-pay threshold of €11,800. CONCLUSIONS: Enrolment of patients into the SCAD programme is highly cost-effective. Extension of the programme to other hospitals and more patients would have a limited budget impact but provide important clinical benefits. This finding should also be taken into account in new public health policies aimed at encouraging a shift from inpatient to ambulatory care.

Volumetric parcellation of the cardiac right ventricle for regional geometric and functional assessment.

3D echocardiography is an increasingly popular tool for assessing cardiac remodelling in the right ventricle (RV). It allows quantification of the cardiac chambers without any geometric assumptions, which is the main weakness of 2D echocardiography. However, regional quantification of geometry and function is limited by the lower spatial and temporal resolution and the scarcity of identifiable anatomical landmarks, especially within the ventricular cavity. We developed a technique for regionally assessing the volume of 3 relevant RV volumetric regions: apical, inlet and outflow. The proposed parcellation method is based on the geodesic distances to anatomical landmarks that are easily identifiable in the images: the apex and the tricuspid and pulmonary valves, each associated to a region. Based on these distances, we define a partition in the endocardium at end-diastole (ED). This partition is then interpolated to the blood cavity using the Laplace equation, which allows to compute regional volumes. For obtaining an end-systole (ES) partition, the endocardial partition is transported from ED to ES using a commercial image-based tracking software, and then the interpolation process is repeated. We assessed the intra- and inter-observer reproducibility using a 10-subjects dataset containing repeated quantifications of the same images, obtaining intra- and inter- observer errors (7-12% and 10-23% respectively). Finally, we propose a novel synthetic mesh generation algorithm that deforms a template mesh imposing a user-defined strain to a template mesh. We used this method to create a new dataset for involving distinct types of remodelling that were used to assess the sensitivity of the parcellation method to identify volume changes affecting different parts. We show that the parcellation method is adequate for capturing local circumferential and global circumferential and longitudinal RV remodelling, which are the most clinically relevant cases.

Diagnostic value of quantitative assessment of cardiac 18F-fluoro-2-deoxyglucose uptake in suspected cardiac sarcoidosis.

OBJECTIVE: The identification of cardiac sarcoidosis is challenging as there is no gold standard consensually admitted for its diagnosis. The aim of this study was to evaluate the diagnostic value of the assessment of cardiac dynamic 18F-fluoro-2-deoxyglucose positron emission tomography (18F-FDG PET/CT) and net influx constant (Ki) in patients suspected of cardiac sarcoidosis. METHODS: Data obtained from 30 biopsy-proven sarcoidosis patients suspected of cardiac sarcoidosis who underwent a 50-min list-mode cardiac dynamic 18F-FDG PET/CT after a 24 h high-fat and low-carbohydrate diet were analyzed. A normalized coefficient of variation of quantitative glucose influx constant, calculated as the ratio: standard deviation of the segmental Ki (min-1)/global Ki (min-1) was determined using a validated software (Carimas® 2.4, Turku PET Centre). Cardiac sarcoidosis was diagnosed according to the Japanese Ministry of Health and Welfare criteria. Receiving operating curve analysis was performed to determine sensitivity and specificity of cardiac dynamic 18F-FDG PET/CT analysis to diagnose cardiac sarcoidosis. RESULTS: Six out of 30 patients (20%) were diagnosed as having cardiac sarcoidosis. Myocardial glucose metabolism was significantly heterogeneous in patients with cardiac sarcoidosis who showed significantly higher normalized coefficient of variation values compared to patients without cardiac sarcoidosis (0.513 ± 0.175 vs. 0.205 ± 0.081; p = 0.0007). Using ROC curve analysis, we found a cut-off value of 0.38 for the diagnosis of cardiac sarcoidosis with a sensitivity of 100% and a specificity of 91%. CONCLUSIONS: Our results suggest that quantitative analysis of cardiac dynamic 18F-FDG PET/CT could be a useful tool for the diagnosis of cardiac sarcoidosis.

Left Ventricular Function Assessment Using 2 Different Cadmium-Zinc-Telluride Cameras Compared with a γ-Camera with Cardiofocal Collimators: Dynamic Cardiac Phantom Study and Clinical Validation.

UNLABELLED: This study compared two SPECT cameras with cadmium-zinc-telluride (CZT) detectors to a conventional Anger camera with cardiofocal collimators for the assessment of left ventricular (LV) function in a phantom and patients. METHODS: A gated dynamic cardiac phantom was used. Eighteen acquisitions were processed on each CZT camera and the conventional camera. The total number of counts within a myocardial volume of interest varied from 0.25 kcts to 1.5 Mcts. Ejection fraction was set to 33%, 45%, or 60%. Volume, LV ejection fraction (LVEF), regional wall thickening, and motion (17-segment model) were assessed. One hundred twenty patients with a low pretest likelihood of coronary artery disease and normal findings on stress perfusion SPECT were retrospectively analyzed to provide the reference limits for end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction, and regional function for each camera model. RESULTS: In the phantom study, for each ejection fraction value, volume was higher for the CZT cameras than for the conventional camera, resulting in a decreased but more accurate LVEF (all P < 0.001). In clinical data, body-surface-indexed EDV and ESV (mL/m(2)) were higher for one of the CZT cameras (Discovery NM 530c) than for the other (D-SPECT) or the conventional camera (respectively, 40.5 ± 9.2, 37 ± 7.9, and 35.8 ± 6.8 for EDV [P < 0.001] and 12.5 ± 5.3, 9.4 ± 4.2, and 8.3 ± 4.4 for ESV [P < 0.001]), resulting in a significantly decreased LVEF: 70.3% ± 9.1% vs. 75.2% ± 8.1% vs. 77.8% ± 9.3%, respectively (P < 0.001). CONCLUSION: The new CZT cameras yielded global LV function results different from those yielded by the conventional camera. LV volume was higher for the Discovery NM 530c than for the D-SPECT or the conventional camera, leading to decreased LVEF in healthy subjects. These differences should be considered in clinical practice and warrant the collection of a specific reference database.

Assessment of endothelial function and myocardial flow reserve using (15)O-water PET without attenuation correction.

PURPOSE: Myocardial blood flow (MBF) measurement using positron emission tomography (PET) from the washout rate of (15)O-water is theoretically independent of tissue attenuation. The aim of this study was to evaluate the impact of not using attenuation correction in the assessment of coronary endothelial function and myocardial flow reserve (MFR) using (15)O-water PET. METHODS: We retrospectively processed 70 consecutive (15)O-water PET examinations obtained at rest and during cold pressor testing (CPT) in patients with dilated cardiomyopathy (n = 58), or at rest and during adenosine infusion in heart transplant recipients (n = 12). Data were reconstructed with attenuation correction (AC) and without attenuation correction (NAC) using filtered backprojection, and MBF was quantified using a single compartmental model. The agreement between AC and NAC data was assessed using Lin's concordance correlation coefficient followed by Bland-Altman plot analysis. RESULTS: Regarding endothelial function, NAC PET showed poor reproducibility and poor agreement with AC PET data. Conversely, NAC PET demonstrated high reproducibility and a strong agreement with AC PET for the assessment of MFR. CONCLUSION: Non-attenuation-corrected (15)O-water PET provided an accurate measurement of MFR compared to attenuation-corrected PET. However, non-attenuation-corrected PET data were less effective for the assessment of endothelial function using CPT in this population.

Segmental and global left ventricular function assessment using gated SPECT with a semiconductor Cadmium Zinc Telluride (CZT) camera: phantom study and clinical validation vs cardiac magnetic resonance.

BACKGROUND: We evaluated gated-SPECT using a Cadmium-Zinc-Telluride (CZT) camera for assessing global and regional left ventricular (LV) function. METHODS: A phantom study evaluated the accuracy of wall thickening assessment using systolic count increase on both Anger and CZT (Discovery 530NMc) cameras. The refillable phantom simulated variable myocardial wall thicknesses. The apparent count increase (%CI) was compared to the thickness increase (%Th). CZT gated-SPECT was compared to cardiac magnetic resonance (CMR) in 27 patients. Global and regional LV function (wall thickening and motion) were quantified and compared between SPECT and CMR data. RESULTS: In the phantom study using a 5-mm object, the regression between %CI and %Th was significantly closer to the line of identity (y = x) with the CZT (R (2) = 0.9955) than the Anger (R (2) = 0.9995, P = .03). There was a weaker correlation for larger objects (P = .003). In patients, there was a high concordance between CZT and CMR for ESV, EDV, and LVEF (all CCC >0.80, P < .001). CZT underestimated %CI and wall motion (WM) compared to CMR (P < .001). The agreement to CMR was better for WM than wall thickening. CONCLUSION: The Discovery 530NMc provided accurate measurements of global LV function but underestimated regional wall thickening, especially in patients with increased wall thickness.