bluuebunny/crossref_metadata_2025_split huggingface dataset:
CT-free attenuation correction for cardiac-dedicated CZT SPECT: first results of the CASCTEC study
Authors: Hesse M , Dupont F , Gheysens O , Lhommel R , Roelants V 
Published: June 2024

Abstract

Aim/Introduction
The diagnostic accuracy of myocardial perfusion scintigraphy (MPS) for detecting coronary artery diseases (CAD) is improved when using attenuation-corrected (AC) images. However, for economic reasons, most clinical cardiac-dedicated CZT cameras are marketed without a CT. Therefore, the CASCTEC clinical study aims at developing an approach to generate AC images only from emission scans on a pinhole CZT camera, without the need for CT.

Materials & Methods
Up to now 25 patients referred for MPS have been enrolled in the CASCTEC single-center prospective study. Two-day stress/rest myocardial SPECT imaging was performed on a pinhole CZT camera. A standard of care (SOC) 5-10 minutes acquisition was immediately followed by an additional 5 minutes acquisition after radially retracting the detectors (FAR) without moving the patient. Subsequently all patients underwent SPECT/CT imaging to be used as reference. The FAR acquisition allowed to delineate the patient body contour, and together with the SOC acquisition, enabled the segmentation of soft and lung tissues to produce an attenuation map. Non-corrected (NC) and AC images were compared together and with respect to the SPECT/CT images using the AHA 17-segment model polar maps and a polar sub-segmentation of these maps (104 segments). All (sub-)segments were scored according to their relative perfusion uptake, and combined to generate stress and rest summed scores.

Results
The tracer distribution was found more homogeneous for CASCTEC-AC patient stress and rest perfusion images compared to NC images, and similar to the reference. All perfusion defects observed on the SPECT/CT-AC images were also visible on CASCTEC-AC images. The CASCTEC mean relative uptake increased by up to 40% in the inferior segments compared to the NC image. Changes by less than 10% were observed for all other segments, except for the apical segment that decreased by up to 25%. The differences of the changes in the (17-segment) right coronary artery territories (RCA) summed scores from NC to AC between CASCTEC and SPECT/CT images were 0.2±3.0 (p=0.41) and 0.6±2.2 (p=0.21), respectively for stress and rest scans. Similar results were obtained for the differences of the changes in the (104-segment) RCA summed scores, i.e. 0.1±2.7 (p=0.20) and 0.1±2.4 (p=0.14), respectively for stress and rest scans.

Conclusions
The CASCTEC CT-free patient-specific attenuation map enhances NC perfusion in the inferior wall similarly to CT-based AC images from a SPECT/CT acquisition. This method looks promising to improve the diagnostic accuracy of current cardiac pinhole CZT systems for detecting obstructive CAD but requires further studies.60 years old man – BMI = 30 73 years old man – BMI = 38.5
Descriptive analysis of patients with systemic sclerosis: pilot cohort study
Authors: Aguirre E , Guillen Del Castillo A , Palomar Munoz A , Cardozo-Saavedra A , Aguade-Bruix S , Cuellar-Calabria H , Pizzi M N , Roque A , Simeon Aznar C P , Romero-Farina G 
Published: June 2024

Abstract

Background
In systemic sclerosis (SSc) primary heart involvement, although not exhaustively studied, is frequent and may have prognostic consequences.

Purpose
This pilot cohort study reports a descriptive analysis of patients’ evaluation in a Nuclear Cardiology Unit.

Methods
Prospective study. Between 2012 and 2016, 62 patients (age 56.8 ± 12.9 years, men 12.9%) with SSc referred from the Autoimmune Systemic Diseases Unit for cardiac evaluation were prospectively analyzed. All patients were studied with gated Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging (gSPECT-MPI) during rest, exercise and cold test. Ventricular synchrony was assessed by Emory Cardiac ToolboxTM program, and coronary anatomy was evaluated by coronary computed tomography angiography (CCTA) in all patients. Statistical analyses were performed using STATA 18. StataCorp, College Station, TX, USA.

Results
Most patients were women (86.9%). The prevalence of arterial hypertension (55.7%) and hypercholesterolemia (39.3%) was high, in contrast, the prevalence of diabetes mellitus (4.9%), tobacco (8.2%) and chronic renal failure (3.2%) was low. The prevalence of angina (19.4%), dyspnea (35.5%) and the clinical history of cardiac event (myocardial infarction [n=5], heart failure [n=2], unstable angina [n=4], coronary revascularization [n=1], pericardial diseases [n=2], syncope [n=1]) was high (19.3%). A quarter of the patients had pulmonary arterial hypertension. Electrical conduction disorder was observed in 27.4% of patients (left bundle branch block, right bundle branch block, and left anterior hemiblock), and no patient had a pacemaker. Myocardial ischemia (MIs) (Summed Difference Score ≥ 2) was observed in 24.2% of patients who underwent SPECT exercise-rest and in 22.6% of patients who underwent SPECT cold-rest test. Five percent of patients without MIs in the SPECT cold-rest test presented MIs in the SPECT exercise-rest test, and 8.5% of patients without MIs in the SPECT exercise-rest test had it in the SPECT cold-rest test. The overall agreement for MIs tests was 85.5%. Left ventricular ejection fraction &lt;50% was observed in 12% of patients. Ventricular dyssynchrony (BD &gt; 51º) was observed in 64.5% of patients. A calcium score &gt; 100 AU and a calcium score ≥ 400 AU was observed in 33.9% and 11.5% of patients, respectively. Coronary artery disease was detected in 29% of patients, of which 44% presented significant coronary stenosis (≥ 50%).

Conclusion
This pilot and descriptive study reveals that patients with SSc have cardiac involvement in a non-negligible percentage of the cases and may benefit of a comprehensive evaluation using Nuclear Cardiology techniques among others tests.
Current practices and access to cardiac bone scans for the detection of transthyretin cardiac amyloidosis based on the results of a large national electronic survey
Authors: Hyafil F , Amara W , Andres E , Bardin T , Fournier P , Guignard S , Labeyrie C , Legallois D , Oghina S , Piriou N , Sabouret P , Toulza O , Tresorier R , Walle M , Damy T 
Published: June 2024

Abstract

Background
The diagnosis of transthyretin cardiac amyloidosis (ATTR-CM) requires a good collaboration between physicians to confirm the diagnosis.

Purpose
This study aimed to assess current practices of nuclear medicine (NM) physicians for cardiac scintigraphy with bone radiotracers and to evaluate access to cardiac bone scintigraphy in the healthcare circuit for the diagnosis of ATTR-CM.

Methods
A nationwide electronic survey was sent to 13 830 French physicians including 775 nuclear medicine (NM) physicians to assess their knowledge of 1. clinical signs of amyloidosis and 2. the recommended diagnostic algorithm to identify TTR cardiac amyloidosis. In addition, accessibility, appointment delays and results interpretation difficulties for each of the explorations required to confirm the diagnosis of ATTR-CM were evaluated among different medical specialists. A part of the questionnaire was exclusively dedicated to NM to understand their current practice regarding acquisitions protocols and reporting of cardiac bone scans.

Results
1264 physicians including 148 NM physicians (19 % of all NM physicians contacted) completed the survey. NM physicians who answered to the survey worked in academic hospitals (35 %), general hospitals (31 %), or private practices (26 %). Cardiac bone scans using early acquisitions were performed by 20 % of NM and SPECT acquisitions by 72 %. Grading of cardiac uptake of bone tracers using the Perugini score was carried out by 93 % of the NM, but only 31% and 5% of NM systematically performed heart/whole body or heart/mediastinum signal quantification, respectively. Median (Q1; Q3) delay to obtain results for a cardiac bone scan was estimated at 2 weeks (2; 4) compared to 4 (3; 8) weeks for cardiac MRI, and 2 (2 ; 4) weeks for a biopsy. Among physicians involved in clinical management of patients with ATTR-CM, 68% rarely or never faced difficulties for cardiac scintigraphy. Main difficulties encountered by physicians were: appointment delay (60%), geographical distance (17%), interpretation (12%).

Conclusions
In this large French national survey, access to cardiac bone scintigraphy for patients with a suspicion of ATTR cardiac amyloidosis and quality of reports appear excellent thanks to good adherence of NM physicians to the recommended acquisition protocols for cardiac bone scans and the widespread use of the Perugini grading scale in reports. However, quantitative measurements of cardiac uptake of bone tracers were performed only in one third of bone scans underscoring room for improvement in the next procedural guidelines for cardiac bone scans.
Prognostic value of 99mTc-DPD quantitative SPECT/CT in patients with suspected and confirmed cardiac ATTR-Amyloidosis and preserved left ventricular function
Authors: Gozlugol N , Caobelli F C , Caobelli F C , Bakula A B , Bakula A B , Rominger A R , Rominger A R , Schepers R S , Schepers R S , Stortecky S S , Stortecky S S , Hunziker Munsch L H M , Hunziker Munsch L H M , Dobner S D , Dobner S D , Grani C G , Grani C G 
Published: June 2024

Abstract

Aim
Quantitative 99mTc-3,3-diphosphono-1,2 propanodicarboxylicacid (99mTc-DPD) Single Photon Emission Computed Tomography (SPECT) may be used for risk stratifying patients with transthyretin-related amyloidosis-cardiomyopathy (ATTR-CM). We aimed to analyse the predictive value of quantitative 99mTc-DPD SPECT/CT in suspected and confirmed ATTR-CM according to different disease stages.

Methods
Consecutive patients with suspected ATTR-CM referred to a single tertiary center who underwent quantitative 99mTc-DPD SPECT/CT allowing standardized uptake values (SUVmax, SUVpeak) analysis were enrolled. Patients were divided into two groups according to left ventricular ejection fraction (LVEF) at baseline (i.e. LVEF≥50% and &lt;50%). Correlations between clinical, laboratory, and echocardiographic parameters and major adverse cardiac events (i.e. all-cause death, sustained ventricular tachyarrhythmia, hospitalization for heart failure, implantation of a cardioverter defibrillator) to quantitative uptake values were investigated.

Results
A total of 144 patients with suspected ATTR-CM were included in the study (98 with LVEF≥50% and 46 with LVEF&lt;50%), of whom 99 were diagnosed with ATTR-CM (68,75%; 69 with LVEF≥50% and 30 with LFEV&lt;50%). Myocardial SUVmax≥7 was predictive of MACE at 21.9±13.0 months follow-up (HR 2.875, 95%CI 1.23 – 6.71, p=0.015) in suspected ATTR-CM and in patients with confirmed ATTR-CM (global X²= 6.892, p=0.02) and LVEF≥50%. There was no predictive value for patients with LVEF&lt;50% in suspected or confirmed ATTR-CM.

Conclusions
In patients with suspected or confirmed ATTR-CM and preserved LVEF, representing early disease stage, a myocardial SUV≥7 is a predictive marker for MACEs. Quantitative 99mTc-DPD SPECT should be considered for improved early stage risk stratification of patients with ATTR-CM.
Routine clinical reproducibility of hyperemic myocardial blood flow measurements with 15O-water-PET
Authors: Lubberink M , Nordstrom J , Sigfridsson J , Svanstrom P , Eggers K M , Sorensen J , Kero T 
Published: June 2024

Abstract

Background
Hyperemic myocardial blood flow (MBF) has been shown to provide the most accurate non-invasive diagnosis of hemodynamically significant CAD. A high reproducibility of hyperemic MBF measurements is important for accurate stratification of patients. Previous studies have shown that whole-myocardium hyperemic MBF measurement with 82Rb has a repeatability coefficient (RC) of 50% (1.3 mL/g/min) for a two-day test-retest using adenosine in healthy controls [1] and 21% (0.51 mL/g/min) and 38% (0.90 mL/g/min) for a single-session and two-day test-retest using dipyridamole, respectively, in patients in clinical routine [2]. For 15O-water and adenosine, an RC of 25% (0.90 mL/g/min) has been reported in 1999 for healthy controls, whereas RC at the regional level was &gt;50% [3].

Purpose
The aim of the current work is to assess the reproducibility of hyperemic MBF measurements with 15O-water using state of the art technology.

Methods
Ten patients referred for assessment of ischemia underwent a same day test-retest protocol consisting of 4-min dynamic rest and stress scans starting simultaneously with controlled bolus injection of 400 MBq 15O-water on a digital PET-CT scanner. Patients left the scanner between test and retest sessions and time between test and retest scan sessions was circa 1 h. Adenosine infusion at 140 μg/kg/min was started 2 min prior to each stress scan and continued during the entire scan. Images were analysed using fully automated software. RC (1.96 x SD of test-retest differences), mean relative test-retest difference and within-subject coefficient of variation (wCV) were calculated at the whole myocardium, regional and segmental levels.

Results
Whole myocardium hyperemic MBF ranged from 1.3 to 4.6 mL/g/min. RC was 15% (0.43 mL/g/min), 23% (0.67) and 27% (0.80) at whole myocardium, regional and segmental levels, respectively. Mean test-retest difference was 7%, 10% and 11%, and wCV was 5.5%, 8.3% and 9.8%, respectively. Figure 1 shows scatter plots of MBF values and figure 2 shows stress MBF polarmaps of a typical patient.

Conclusion
Automated data analysis and use of modern PET scanners results in a large improvement of reproducibility of hyperemic MBF measurements with 15O-water. Reproducibility of hyperemic MBF with 15O-water is superior to previously published values for 82Rb.Scatter plot of test-retest MBF values Stress MBF polar maps of one subject
Quantitative evaluation of coronary artery calcium and vascular function by hybrid rubidium-82 PET/CT imaging in heart transplanted patients
Authors: Mannarino T , Assante R , Zampella E , D'antonio A , Cacciatore F , Amarelli C , Falzarano M , Mattucci I , Chiappetti R , Gaudieri V , Buongiorno P , Panico M , Maiello C , Cuocolo A , Acampa W 
Published: June 2024

Abstract

Aim/Introduction
Cardiac myocardial perfusion imaging (MPI) by positron emission tomography (PET)/ computed tomography (CT) represents a noninvasive method used for an integrated measurement of myocardial blood flow (MBF), myocardial flow reserve (MFR) and coronary artery calcium (CAC) content. No study has investigated the relationship between coronary atherosclerotic burden and vascular function in heart transplanted patients. Thus, we assessed the relationship between CAC score, MBF and MFR in heart transplant patients undergoing hybrid 82Rb positron emission tomography (PET)/computed tomography (CT) imaging.

Materials and Methods
We enrolled a total of 100 (mean age 60±13 years) consecutive patients referred to hybrid 82Rb PET/CT myocardial perfusion imaging for evaluation of myocardial ischemia. CAC score was measured according to the Agatston method and patients were categorized into 4 groups (0, 0.01-99.9, 100-399.9, and ≥400). Baseline and hyperemic MBF were automatically quantified. MFR was calculated as the ratio of hyperemic to baseline MBF and it was considered reduced when &lt;2. The Spearman correlation coefficient was assessed between continuous CAC score and MBF or MFR values. Univariable and multivariable logistic regression analyses were used to determine the variables associated with reduced MFR.

Results
Global CAC score showed a significant inverse correlation with hyperemic MBF (r=-0.28, P &lt; .05) and MFR (r=-0.40, P &lt; .001), while no correlation between CAC score and baseline MBF was found (P = 0.9). CAC score was zero in 71 (71%) patients, 0.1-99.9 in 8 (8%), 100-399.9 in 12 (12%), and ≥400 in 9 (9%). Global baseline MBF was comparable among the four groups of patients at different levels of CAC score (F = 0.040, P = 0.989). Whereas hyperemic MBF (F = 2.897) and MFR (F = 4.344) progressively decreased with increasing CAC levels (P for trend &lt;0.05). Univariable analysis demonstrated that age, diabetes, and CAC score (all P &lt; .05) were associated with reduced MFR. At multivariable logistic regression analysis only age and CAC score (both P &lt; .05) were independently associated with reduced MFR. The addition of CAC score to clinical data, increased the global chi-square value for predicting reduced MFR from 18.79 to 25.66 (P &lt; .01).

Conclusion
In heart transplanted patients there was an inverse relationship between CAC score and MFR. The evaluation of calcium content might be helpful for identifying patients with a reduced MFR, at high risk to develop cardiac allograft vasculopathy.MBF across CAC score categories MFR across CAC score categories
Ischaemic burden reduction and impact on absolute perfusion in remote myocardium after chronic total occlusion percutaneous coronary intervention
Authors: Carlos T , Leite L , Campos G , Rocha L , Silva R , Abrunhosa A , Gomes A , Castelo-Branco M , Goncalves L , Ferreira M J 
Published: June 2024

Abstract

Background
Chronic total coronary occlusion (CTO) poses a complex challenge in angiographic hemodynamics. Blood supply to the affected myocardium is dependent on the formation of collateral network from adjacent vessels. However, this coronary steal phenomenon reduces myocardial blood flow (MBF) to the remote myocardium, particularly under stress conditions. Limited data exist on myocardial quantitative perfusion alterations in both these regions following intervention.

Purpose
To assess the effect of percutaneous coronary intervention (PCI) on MBF (measured in mL.min-1.g-1) in both CTO territory and remote myocardium, using [13N]NH3 positron emission tomography computed tomography (PET-CT).

Methods
We conducted a single-centre prospective study on patients with CTO, who had myocardial quantitative perfusion evaluation by [13N]NH3 PET-CT both pre- and post- PCI. Patients with no indication for PCI according to prevailing guidelines, inadequate follow-up, insufficient data or absence of either pre- or post- procedure [13N]NH3 PET-CT were excluded.

Results
Within our cohort of 19 patients with CTO, 13 individuals underwent PCI and pre- and post- procedural assessment using [13N]NH3 PET-CT. The mean age was 68 years (± 4.3) and 76.9% were male. Following PCI, hMBF demonstrated significant improvement in the CTO territory (Δ 0.36 ± 0.34, p=0.003), whereas no statistically significant differences were observed in the remote myocardium (Δ 0.05 ± 0.21, p=0.423). At rest, MBF did not significantly change after PCI in either CTO territory (Δ 0.06 ± 0.21, p=0.351) or remote myocardium (Δ 0.04 ± 0.16, p=0.444). Myocardial flow reserve also showed no statistically significant differences between the two groups. Notably, alterations in MBF in the CTO territory exhibited a strong linear correlation with the corresponding changes in the remote myocardium (hMBF: r=0.732, p=0.004; rMBF: r=0.958, p&lt;0.001).

Conclusion
PCI enhanced myocardial perfusion, mainly in stress conditions and in the CTO dependent territory. Restoring blood flow through the CTO vessel normally results in regression of the collateral network and subtly improves perfusion of the remote myocardium. In our study, this effect was more pronounced when there was a greater improvement in the CTO territory perfusion, likely due to a previously larger coronary steal phenomenon, that diminished after PCI. Figure 1
Myocardial ischemic burden and angiographic assessment of collateral network in patients with chronic total coronary occlusion
Authors: Carlos T , Bahadoran A , Leite L , Campos G , Rocha L , Silva R , Gomes A , Abrunhosa A , Castelo-Branco M , Goncalves L , Ferreira M J 
Published: June 2024

Abstract

Background
Chronic total coronary occlusion (CTO) myocardial territories maintain perfusion via collateral circulation from adjacent vessels, thereby preventing transmural myocardial infarction and partially preserving ventricular function. The collateral network may be categorized based on its angiographic characteristics, using either Rentrop or Werner classification, which may be used to evaluate the need for revascularization. Nevertheless, their relationship with myocardial ischemic burden is not entirely established.

Purpose
To assess whether collateral angiographic characteristics of patients with CTO have an impact on quantitative myocardial ischemic burden, evaluated by [13N]NH3 positron emission tomography computed tomography (PET-CT).

Methods
We conducted a single-centre observational prospective study on patients with CTO who had angiographic characteristics assessed by coronariography and quantitative myocardial perfusion in CTO territory measurements assessed by [13N]NH3 PET-CT, using the quantification software PCARDP (PMOD Cardiac PET Analysis Tool). Patients with insufficient data were excluded. Well developed (WD) collaterals were defined as a concomitant angiographic Rentrop grade 3 and Werner collateral connection score 2 or 3, whereas the remaining were categorized as poorly developed (PD).

Results
A total of 15 patients, with a mean age of 66.8 years (±4.2) and a male prevalence (80%) were included. The most affected artery was the right main coronary artery (60%). Regarding collateral evaluation, 9 patients (60%) had WD collateral circulation. When comparing myocardial ischemic burden using quantitative parameters, no statistically significant differences were observed between patients exhibiting WD and PD collateral circulation (hyperaemic myocardial blood flow, measured in mL.min-1.g-1: WD 1.24±0.53 vs. PD 1.25±0.38, p=0.971; rest myocardial blood flow, measured in mL.min-1.g-1: WD 0.66±0.17 vs. PD 0.74±0.32, p=0.513; myocardial flow reserve: WD 1.91±0.59 vs. PD 1.91±0.81, p=0.893).

Conclusion
The angiographic evaluation of collateral network and subsequent categorization in WD and PD collaterals in patients with CTO revealed no significant association with the observed myocardial ischemic burden in these patients. Therefore, its utility to guide decisions concerning percutaneous intervention benefit should be used cautiously.