bluuebunny/crossref_metadata_2025_split huggingface dataset:
Additional ultra-low-dose protocols in coronary computed tomography angiography scans to early detection of lung cancer
Authors: Forte G C , Andrade R G F , Fiorentini L F , Irion K , Hochhegger B 
Published: October 2021

Abstract

Background
Chest CT screening improves lung cancer detection at early stages for high-risk populations, such as heavy-smokers. However, CT screening also has some considerable disadvantages as radiation exposure, patient distress and overdiagnosis. Tobacco is also a major risk factor for coronary heart disease.

Purpose
To assess whether an additional chest ultra-low-dose CT scan to the coronary CT angiography protocol can be used for lung cancer screening among patients with suspected coronary artery disease.

Methods
980 patients underwent coronary CT angiography for assessment of coronary artery disease, additionally undergoing ultra-low-dose CT screening to early diagnosis of lung cancer in the same scanner (80kVp and 15mAs). Patients presenting pulmonary nodules were followed-up for two years, repeating low-dose CTs in intervals of 3, 6, or 12 months based on nodule size and growth rate in accordance with National Comprehensive Cancer Network guidelines.

Results
Ultra-low-dose CT identified 437 patients with solitary pulmonary nodules (45%), with a mean diameter of 5.40±4.10mm. One hundred fifty two were &gt;6mm, and in 83% (n=126) of these cases they were false positive findings, further confirmed by follow-up (n=114), resection (n=3), or biopsy (n=9). Lung cancer was detected in twenty nine patients due to CT screening (diagnostic yield: 2.9%). Among these, 20 cases could not be detected in the cardiac field of view. Most patients were in early stages of the disease, and eight patients diagnosed at advanced stages (IIIB and IV). The addition of the ultra-low-dose CT scan represented a radiation dose increment of 1.32±0.29% (effective dose, 0.12±0.04mSv).

Conclusions
Lung cancer might be detected using additional ultra-low-dose protocols in coronary CT angiography scans among patients with suspected coronary artery disease.

Funding Acknowledgement
Type of funding sources: None.
Optimal measurement location of on-site based CT-derived FFR on midterm prognosis
Authors: Okada-Nozaki Y , Fujimoto S , Aoshima C , Kamo Y , Okano-Kawaguchi Y , Takamura K , Kudo A , Takahashi D , Hiki M , Dohi T , Okazaki S , Tomizawa N , Minamino T 
Published: October 2021

Abstract

Background
Fractional Flow Reserve (FFR) derived from coronary computed tomography angiography (CCTA) enables anatomical and hemodynamical assessment of coronary artery disease. CT-FFR, which can be acquired on-site workstation using fluid structure interaction during the multiple optimal diastolic phase, has an incremental diagnostic value over conventional CCTA. However, few studies are focused on investigating the appropriate measurement location of CT-FFR, considering the prognosis, using CCTA as a standalone modality.

Purpose
The aim of this study is to assess the clinical impact on CT-FFR with an appropriate measurement.

Methods
A total of 370 consecutive patients who underwent CCTA in a single-heartbeat scan with a phase window of 70% to 99% of the R-R interval, showing 50–90% stenosis of at least one major epicardial vessel measuring ≥1.8 mm in diameter on CCTA were retrospectively analyzed and followed during a median follow up 2.9 years. CT-FFR values were measured at three points: 1, 2 cm distal to a target lesion (CT-FFR1cm, 2cm) and the vessel terminus (CT-FFRlowest), and a CT-FFR value ≤0.80 was considered abnormal. The endpoint was MACE, a composite of cardiac death, non-fatal MI, and unplanned revascularization.

Results
The incidence of MACE occurred in 8.4% (31/370) of the whole patients, including four cardiac deaths, ten all cause deaths, two non-fatal MI, and twenty unplanned revascularization. The Kaplan-Meier survival analysis demonstrated a significantly higher cumulative MACE rate in patients with positive CT-FFR1cm and 2cm than those with negative CT-FFR1cm and 2cm, while there was no significant difference between negative and positive in CT-FFRlowest, among patients with negative CT-FFR1cm and 2cm (Figure 1). Among 221 patients, who did not perform early revascularization within 90 days from CCTA, there was no significant difference in CT-FFRlowest in the incidence of MACE. In contrast, the risk of MACE was significantly higher in both positive CT-FFR1cm and CT-FFR2cm (Figure 2).

Conclusion
From a view point of clinical outcome for patients with moderate to severe stenosis on CCTA, a CT-FFR value when measured at 1-to-2 cm distal to a target lesion could be feasible for the deferral of unnecessary invasive coronary angiography safely. Moreover, CT-FFR1–2cm showed better risk stratification measurement rather than CT-FFRlowest, based on future adverse cardiac event.

Funding Acknowledgement
Type of funding sources: Private company. Main funding source(s): Canon Medical Systems Corporation Kaplan-Meier 1Kaplan-Meier 2
Characteristics of aortic root and vascular anatomy in bicuspid versus tricuspid aortic valve anatomy
Authors: Hamdan A , Witberg G , Perlman G , Aviv Y , Shiyovich A , Vaknin Assa H , Abid Assali A , Lessick J , Kerner A , Segev A , Barabash I , Goitein O , Brodov Y , Finkelstein A , Kornowski R 
Published: October 2021

Abstract

Background
Transcatheter aortic valve replacement (TAVR) is being increasingly performed in patients with bicuspid aortic valve stenosis (AS).

Purpose
This study sought to compare aortic root, aorta and iliofemoral artery anatomy in patients with bicuspid versus tricuspid AS.

Methods
172 patients with bicuspid AS and 331 patients with tricuspid AS underwent pre-procedural computed tomography (CT) evaluation before TAVR. Dimensions, calcification, and tortuosity of the iliofemoral arteries were evaluated and the dimensions of aortic root, aorta, and left subclavian arteries were determined.

Results
Dimensions of aortic root, aorta, left subclavian, and iliofemoral arteries were consistently and significantly larger in bicuspid than in tricuspid AS (P&lt;0.001). Patients with bicuspid AS had significantly lower subclavian, aorta, and iliofemoral arteries calcification, lower tortuosity index and lower maximal tortuosity angle compared to patients with tricuspid AS (P&lt;0.001 for all) even after adjustment for baseline characteristics (Figure). Compared to tricuspid AS the prevalence of porcelain aorta and aneurysm in the descending aorta and iliofemoral arteries were significantly less common in bicuspid valve anatomy. After adjustment for baseline characteristics Bicuspid valve anatomy was associated with lower odds of vascular calcification (odds ratio (OR) 0.82: 95% CI 0.52–0.93; P=0.001).

Conclusions
Bicuspid AS was associated with larger dimensions of aortic root, aorta, subclavian, and iliofemoral arteries compared with tricuspid AS. Low vascular calcification and decreased tortuosity index of iliofemoral arteries characterized bicuspid anatomy. Further studies are needed to evaluate the impact of bicuspid vascular anatomy on vascular complications after TAVR.

Funding Acknowledgement
Type of funding sources: None.
Prevalence of coronary artery disease among patients with bicuspid aortic valve stenosis undergoing computed tomography before transcatheter aortic valve implantation
Authors: Wiessman M , Aviv Y , Shafir G , Kornowski R , Hamdan A 
Published: October 2021

Abstract

Introduction
A lower prevalence of coronary artery disease (CAD) was previously reported among bicuspid aortic valve (BAV) patients compared with tricuspid aortic valve (TAV) patients undergoing surgical aortic valve replacement. Unknown is the prevalence of CAD among BAV patients undergoing transcatheter aortic valve implantation (TAVI).

Methods
Consecutive BAV patients undergoing cardiac computed tomography angiography (CCTA) before TAVI were included. Studies with insufficient imaging quality were excluded. Forty-nine patients with history of prior percutaneous coronary intervention or coronary artery bypass graft surgery were also excluded. Coronary artery stenosis was categorized as ≤50% or &gt;50% luminal diameter stenosis.

Results
One hundred and fourteen consecutive BAV patients were enrolled (age 72±10.4 years, 64% males). BAV type 1A was the most common type (62%), followed by BAV type 0 (18%) and type 1C (10%). Cardiovascular risk factors were frequent: 23% (26) had history of diabetes mellitus, 45% (51) had dyslipidemia, 56% (64) had hypertension, and 25% (29) were current or past smokers. No correlation was found between calcium scoring of the aortic valve (3664.49±1671.01 Agatston Units) and calcium scoring of the coronary arteries (410.51±546.59 Agatston Units), correlation coefficient 0.43 (p=0.68). Obstructive coronary artery stenosis (&gt;50% luminal diameter stenosis) was observed among the minority (16%) of BAV patients. A single vessel disease was found in 7% of BAV patients, two vessels disease in 5% and triple vessels disease in 4%. Three BAV patients had a single vessel chronic total occlusion.

Conclusion
Among patients with BAV referred for TAVI, CCTA showed a low prevalence of obstructive coronary artery disease. The absence of correlation between aortic valve and coronary artery calcium scoring suggests the possibility of two heterogeneous aspects of the complex BAV disease.

Funding Acknowledgement
Type of funding sources: None.
Computed tomography-derived characterisation of pericoronary,epicardial and paracardial adipose tissue and its association with myocardial ischemia as assessed by computed and invasive fractional flow
Authors: Goeller M , Duncker H , Moshage M , Dey D , Bittner D , Ammon F , Achenbach S , Marwan M 
Published: October 2021

Abstract

Introduction
Increased pericoronary adipose tissue (PCAT) computed tomography (CT) attenuation derived from coronary CT angiography (CTA) around the right coronary artery (RCA) reflects coronary inflammation and relates to cardiac mortality.

Purpose
We aimed to investigate the yet unclear association between CT-derived characterisation of different cardiac adipose tissue compartments and the presence of myocardial ischemia as assessed by fractional flow reserve (FFR).

Methods
133 stable individuals (64 years, 74% male) with coronary artery disease (CAD) underwent CTA including computed FFR (FFR-CT) measurement followed by invasive angiography with FFR (invasive FFR) assessment. The CT attenuation (HU) and volume (mm3) of PCAT were quantified around the RCA (10 to 50 mm from RCA ostium), the proximal 40 mm of the left anterior descending artery (LAD) and the circumflex artery (LCX) with the help of semi-automated software. The per patient PCAT CT attenuation was calculated as followed: (PCAT CT attenuation of RCA+LAD+LCX)/3. Quantification of epicardial adipose tissue (EAT) and paracardial adipose tissue (PAT; all intrathoracic adipose tissue outside the pericardium) were performed in non-contrast cardiac CT data sets using a fully automated deep-learning based algorithm.

Results
Median FFR-CT was 0.86 [0.79, 0.91] and median invasive FFR was 0.87 [0.81, 0.93]. Patients with presence of myocardial ischemia (n=26) defined by a FFR-CT threshold of ≤0.75 showed a significant higher PCAT CT attenuation of RCA (−75.1 HU vs. −81.1 HU, p=0.011) and per patient (−74.5 HU vs. −77.7 HU, p=0.045) than individuals without myocardial ischemia (n=107). In multivariable analysis adjusted for age, BMI, gender and traditional risk factors, both RCA and per patient PCAT CT attenuation were significant predictors of myocardial ischemia as assessed by FFRCT ≤0.75. Between individuals with myocardial ischemia compared to individuals without myocardial ischemia there was no significant difference neither in the volume and CT attenuation of EAT and PAT nor in the PCAT volume of RCA, LAD, LCX and per patient PCAT volume.

Conclusions
Our observations suggest that PCAT CT attenuation instead of PCAT volume, EAT and PAT measures might be associated with the presence of myocardial ischemia as assessed by FFR.

Funding Acknowledgement
Type of funding sources: Foundation. Main funding source(s): German Heart Foundation e.V.
Incorporating coronary calcification into pretest assessment of the likelihood of coronary artery disease: validation and recalibration of a new diagnostic tool
Authors: Lopes P , Presume J , Goncalves P A , Albuquerque F , Freitas P , Guerreiro S , Abecasis J , Santos A C , Saraiva C , Mendes M , Marques H , Ferreira A 
Published: October 2021

Abstract

Background
A new clinical tool was recently proposed to improve the estimation of pre-test probability of obstructive coronary artery disease (CAD) by incorporating coronary artery calcium score (CACS) with clinical risk factors. This new model (Clinical+CACS) showed improved prediction when compared to the method recommended by the 2019 ESC guidelines on chronic coronary syndromes, but was never tested or adjusted for use in our population. The aim of this study was to assess the performance of this new method in a Portuguese cohort of symptomatic patients referred for coronary computed tomography angiography (CCTA), and to recalibrate it if necessary.

Methods
We conducted a two-center cross-sectional study assessing symptomatic patients who underwent CCTA for suspected CAD. Key exclusion criteria were age &lt;30 years, known CAD, suspected acute coronary syndrome, or symptoms other than chest pain or dyspnea. Obstructive CAD was defined as any luminal stenosis ≥50% on CCTA. The Clinical+CACS prediction model was assessed for discrimination and calibration. A logistical recalibration of the model was conducted in a random sample of 50% of the patients and subsequently validated in the other half.

Results
A total of 1910 patients (mean age 60±11 years, 60% women) were included in the analysis. Symptom characteristics were: 39% non-anginal chest pain, 30% atypical angina, 19% dyspnea and 12% typical angina. The observed prevalence of obstructive CAD was 12.9% (n=247). Patients with obstructive CAD were more often male, were significantly older, had higher prevalence of typical angina and cardiovascular risk factors, and higher CACS values. The new Clinical+CACS tool showed greater discriminative power than the ESC 2019 prediction model, with a C-statistic of 0.83 (CI 95% 0.81–0.86) versus 0.67 (CI 95% 0.64–0.71), respectively (p-value for comparison &lt;0.001). Before recalibration, the Clinical+CACS model underestimated the likelihood of CAD in our population across all quartiles of pretest probability (mean relative underestimation of 49%), which was subsequently corrected by the recalibration procedure - Figure.

Conclusions
In a Portuguese cohort of symptomatic patients undergoing CCTA for suspected CAD, the new Clinical+CACS model showed better discrimination power than the 2019 ESC method. The underestimation of the Clinical+CACS model was corrected by recalibrating it for our population. This new tool might prove useful for guiding decisions on the need for further testing.

Funding Acknowledgement
Type of funding sources: None.
Machine learning from quantitative coronary computed tomography angiography predicts ischemia and impaired myocardial blood flow
Authors: Lin A , Van Diemen P , Motwani M , McElhinney P , Otaki Y , Han D , Kwan A , Tzolos E , Cadet S , Danad I , Driessen R , Slomka P J , Berman D S , Dey D , Knaapen P 
Published: October 2021

Abstract

Background
Atherosclerotic plaque characteristics influence the hemodynamic consequences of coronary lesions. This study sought to assess the performance of a machine learning (ML) score integrating coronary computed tomography angiography (CCTA)-based quantitative plaque features for the prediction of ischemia by invasive fractional flow reserve (FFR) and impaired myocardial blood flow (MBF) by [15O]H2O positron emission tomography (PET).

Methods
This post-hoc analysis of the PACIFIC (Prospective Comparison of Cardiac PET/CT, SPECT/CT Perfusion Imaging and CT Coronary Angiography With Invasive Coronary Angiography) trial included 208 patients with suspected coronary artery disease who underwent CCTA, [15O]H2O PET, and 3-vessel invasive FFR. Plaque quantification from CCTA was performed using semiautomated software. A boosted ensemble ML algorithm (XGBoost) trained on data from the NXT (Analysis of Coronary Blood Flow using CT Angiography: Next Steps) trial was used to develop a ML score for the prediction of per-vessel ischemia (invasive FFR ≤0.80). The performance of the ML score was evaluated in 551 vessels from the PACIFIC trial for external validation. Thereafter, we assessed the discriminative ability of the ML score for per-vessel impaired hyperemic MBF (≤2.30 mL/min/g).

Results
In total, 138 (25.0%) vessels had ischemia and 195 (35.4%) vessels had impaired hyperemic MBF. CCTA-derived quantitative percent diameter stenosis and low-density noncalcified plaque (LDNCP) volume were higher in ischemic vessels compared with non-ischemic vessels (60.8% vs. 19.9%; and 42.3 mm3 vs. 9.1 mm3; both p&lt;0.001). The ML score demonstrated a significantly higher area under the receiver-operating characteristic curve (AUC) for predicting ischemia (0.92, 95% confidence interval [CI] 0.89–0.94) compared with visual stenosis grade (0.84, 95% CI 0.80–0.87; p&lt;0.001). Overall, quantitative percent diameter stenosis and LDNCP volume had greatest feature importance for ML, followed by percent area stenosis, minimum luminal diameter, and contrast density drop (Figure 1). An individualized explanation of ML ischemia prediction is shown in Figure 2. When applied for impaired MBF discrimination, the ML score exhibited an AUC of 0.82 (95% CI 0.78–0.85) and was superior to visual stenosis grade (AUC 0.76, 95% CI 0.72–0.80; p=0.03).

Conclusions
An externally validated ML score integrating CCTA-based quantitative plaque features accurately predicts FFR-defined ischemia and abnormal MBF by PET, outperforming standard visual CCTA interpretation.

Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Heart, Lung, and Blood Institute, United States Performance of the ML scoreIndividual explanation of ML prediction
Regadenoson stress CMR: safety, feasibility and hemodynamic response
Authors: Muniz Saenz-Diez J , Ezponda A , Gavira J J , Riesgo A , Shanhutov O , De La Torre Carazo F , Rodriguez Junquera M , Irazusta Olloquiegui X , Saenz Idoate V , Torres Santamaria M J , Parreno Benito J , Larrea A , Soriano Aguadero I , Caballeros F M , Bastarrika G 
Published: October 2021

Abstract

Background and objectives
The use of regadenoson for stress cardiac magnetic resonance (CMR) has potential advantages over other vasodilators. We sought to evaluate the safety, feasibility and hemodynamic response (heart rate and blood pressure) of regadenoson in an unselected population undergoing stress CMR for clinical work-up.

Methods
A total of 603 regadenoson stress CMR clinical examinations performed between May 2017 and May 2020 in our institution were retrospectively reviewed. Studies were performed using a conventional stress/rest CMR protocol with a 1.5T MRI scanner. A fixed dose of 5 ml of regadenoson was employed as stressor. As part of the protocol, 200 mg of theophylline was administered between stress and rest acquisitions to reverse the vasodilator effect of regadenoson. Adverse events, clinical symptoms, and hemodynamic response were assessed.

Results
In our cohort, no severe adverse events requiring hospitalization were observed, and only 5 adverse events were reported (0.83%). Only two patients (0.3%) did not complete the test due to adverse events or symptoms related to regadenoson administration (one case presented severe hypotension; the other presented unbearable chest pain). There were no cases of bronchospasm, stress-induced arrhythmia or death. Over half of patients reported mild symptoms after drug administration (52%, n=314), more frequently dyspnea (19%, n=112), chest pain (18%, n=106) and flushing (6%, n=34). All symptoms resolved after theophylline administration. Overall, an increase in heart rate (mean increase and (standard deviation) = 24 (12.6) bpm and a mild decrease in systolic (−8.2 (17.1) mmHg) and diastolic (−4.9 (10.2) mmHg) blood pressure were observed as response to regadenoson. A blunted heart rate response was observed in elderly (p&lt;0.01), diabetic (p&lt;0.01) and obese (p=0.01) patients. Only 46 patients (7.8%) did not show tachycardization response.

Conclusions
The use of regadenoson in stress CMR proved to be safe and feasible in the vast majority of patients. Adverse events were not frequent with regadenoson and symptoms were transient and well tolerated, while premature ending of the test related to drug administration was very rare.

Funding Acknowledgement
Type of funding sources: None. Hemodynamic response
Reproducibility of non-invasive VT substrate characterization: finding the same paths
Authors: Silva Garcia E , Villanueva D , Delgado W , Berruezo A , Soto-Iglesias D , Fernandez-Armenta J 
Published: October 2021

Abstract

Background
Delayed enhancement gadolinium MRI is a useful technique to identify myocardial scar. The objective of this study is compare the reproducibility of the scar quantification and characterization based on cardiac MRI.

Methods
10 patients with ischemic ethology underwent to 1,5T DE-MRI acquisition for myocardial scar analysis. Images were processed using a commercial software (ADAS3D-Galgo Medical) and different parameters from scar tissue (mass of the scar, core of scar and border zone expressed in grams) were analysed. Conducting channels evaluation was obtained by the number of corridors and the mass of the border zone of those corridors. To perform this analysis, 2 experienced and 1 non experienced users segmented DE-MRI acquisition in order to evaluate the inter observer variability. Bland-Altman analysis was employed to evaluate the comparison between the measurements.

Results
Inter observer agreement between experienced users was high (table). The mean and the standard deviation of the differences between two measurements for the scar mass was −3,9±14,66 gr. Analysing the scar tissue divided in core and border zone, the mass of these volume tissues were very similar (−3,51±4,56gr and −0,4±12,87gr respectively. Regarding conducting channels characteristics, the mean of the differences was 0±2 for the number of channels and 1,71±7,76 gr for the mass on the border zone of the corridors. Comparing the measurements between one of the experienced users and the beginner user, results were similar but significant differences were found on the mass of the core and the number of channels, with a variability of ±2 channels (table).

Conclusions
Left ventricular scar size and characteristics derived from late gadolinium enhanced post-processed images are highly reproducible between experienced observers.

Funding Acknowledgement
Type of funding sources: None. Table 1Scar analysis performed by 3 users