1,721,478 research outputs found
Correlation of FFR-derived from CT and stress perfusion CMR with invasive FFR in intermediate-grade coronary artery stenosis
No full textOnly one-third of intermediate-grade coronary artery stenosis (i.e. 40–70% diameter narrowing) causes myocardial ischemia, requiring most often additional invasive work-up with invasive fractional flow reserve (FFR). To evaluate the correlations between FFR estimates derived from computed tomography (FFRCT) and adenosine perfusion cardiac magnetic resonance (CMR) with invasive FFR in intermediate-grade stenosis. Thirty-seven patients (mean age 61 ± 9 years; 25 men) who underwent adenosine perfusion CMR, quantitative coronary angiography and FFR in the work-up for intermediate-grade stenoses (n = 39) diagnosed at coronary CT angiography were retrospectively evaluated. Blinded FFRCT analysis was computed on each intermediate-grade lesion and correlated to the FFR values. On adenosine CMR, subendocardial time-enhancement maximal upslopes, normalized by respective left ventricle cavity upslopes, were obtained distal to a coronary stenosis (RISK area) and in remote myocardium (REMOTE area). The perfusion was subsequently assessed without (uncorrected RISK) and after correction for remote perfusion (relative myocardial perfusion index = REMOTE/RISK ratio), and then correlated to the FFR values. Differences in correlations were tested with z statistics and considered statistically significant different at a p < 0.05 level. The average FFR value was 0.85 ± 0.10 (0.60–0.98 range), 28% (n = 11) was ≤ 0.80. FFR value correlated poorly with uncorrected RISK upslopes (r = 0.151; p = 0.36), but equally strongly with FFRCT (r = 0.675; p < 0.001) and the relative myocardial perfusion index (r = − 0.63) (p < 0.001; z = 6.72) for assessment of lesion-specific ischemia. Both FFRCT and adenosine perfusion CMR strongly correlate with invasive FFR measurements for intermediate-grade stenosis. These preliminary findings pave the way for further studies evaluating non-invasively intermediate coronary stenosis in clinical practice.This study has received funding by General Electrics Healthcare. The funding has been used to cover the costs of the adenosine perfusion MR, the contrast medium and adenosine of all included patients. Funding for the FFRCT analysis was received by Bracco imaging
Multicenter evaluation of a next-generation balloon-expandable transcatheter aortic valve
No full textAbstractBackgroundThe SAPIEN 3 (Edwards Lifesciences Inc., Irvine, California) transcatheter valve incorporates features designed to address the well-known deficiencies of transcatheter aortic valve replacement (TAVR). An ultra–low-profile delivery system facilitates safe, controlled, and accurate implantation and an external seal minimizes paravalvular regurgitation.ObjectivesThe study evaluated whether TAVR with this third-generation valve would be a viable alternative to high- or intermediate-risk surgery for severe aortic stenosis.MethodsThe prospective study enrolled 150 patients at 16 sites in Europe and Canada. Clinical and echocardiographic outcomes were assessed at baseline, post-procedure, and 30 days. New sizing recommendations were developed during the course of the study.ResultsPatients were 83.6 ± 5.0 years of age, with multiple comorbidities reflected by a Society of Thoracic Surgeons score of 7.4 ± 4.5% and logistic EuroSCORE of 21.6 ± 12.3%. A transfemoral approach was chosen in 64.0% and alternative access (transapical/direct aortic) in the remainder. At 30 days, paravalvular regurgitation was none to mild in 96.4% and moderate in 3.5%. No patient had severe regurgitation. Transfemoral implantation was associated with low mortality (2.1%), no disabling stroke (0.0%), and fully percutaneous access and closure in 95.8%. Nontransfemoral alternative access was associated with higher rates of mortality (11.6%) and stroke (5.6%).ConclusionsThis third-generation device addresses major deficiencies of earlier valves in terms of ease of use, accuracy of positioning, and paravalvular sealing. The rates of mortality and stroke with transfemoral access are among the lowest reported and support further evaluation as an alternative to open surgery in intermediate-risk patients. (Safety and Performance Study of the Edwards SAPIEN 3 Transcatheter Heart Valve [SAPIEN3]; NCT01808287
Sex differences in computed tomography coronary stenosis severity versus flow impairment and impact on revascularization, clinical events and healthcare costs: a FORECAST substudy
No full textBackground: the impact of sex related differences in coronary atheroma and flow impairment severity on clinical events and costs remains unclear.Methods and Results: this is a secondary analysis of patients with stable coronary artery disease (CAD) who underwent both coronary computed tomography angiography (CCTA) and fractional flow reserve derived from computed tomography (FFRCT) as part of the FORECAST trial, investigating: (a) the relationship between coronary stenosis severity on CCTA and FFRCT by sex and (b) the association with revascularization, resource utilization and adverse clinical events. 212 patients (64 female participants, 32.1%) and 1245 vessels were included. There was no significant sex difference in the frequencies of significant (38.2% of females vs 51.3% of males, p=0.073) but female participants had significantly less coronary flow impairment, according to the presence of at least one FFRCT≤0.8 (47.0% vs 71.5%, p=0.008). Female subjects underwent fewer revascularization procedures (23.5% vs 42.3%, p=0.014), less CABG (2.9% vs 13.1%, p=0.025) and were less likely to be on statin treatment (72.0% vs 84.7%, p=0.022) by 9-month follow-up. This resulted in lower overall healthcare costs for female participants compared with male counterparts (median total cost £1276 vs £2051, p=0.014). In multivariable Cox analysis the presence of significant CAD (HR 2.91; 95% confidence interval [CI] 1.30-6.51) and having a positive FFRCT (HR 4.11; 95% CI 1.15-14.69) were independent predictors of MACE at 9-months, whereas sex was not statistically significant (p=0.13).Conclusions: there are significant sex differences in the anatomico-functional assessment of coronary artery disease leading to differences in clinical management, costs and adverse events. <br/
Dual energy imaging and intracycle motion correction for CT coronary angiography in patients with intermediate to high likelihood of coronary artery disease
Full text linkWe explored whether intracycle motion correction algorithms (MCAs) might be applicable to dual energy computed tomography coronary angiography in patients with intermediate to high likelihood of coronary artery disease. MCA reconstructions were associated with higher interpretability rates (96.7% vs 87.9%, P < .001), image quality scores (4.12±0.9 vs. 3.76±1.0; P < .0001), and diagnostic performance [area under the curve of 0.95 (95% confidence interval [CI] 0.92-0.97) vs 0.89 (95% CI 0.86-0.92); P < .0001] compared to conventional reconstructions. In conclusion, application of intracycle MCA reconstructions to dual energy computed tomography acquisitions was feasible and resulted in significantly higher image quality scores, interpretability, and diagnostic performance.Fil: Carrascosa, Patricia. Diagnóstico Maipú; ArgentinaFil: Deviggiano, Alejandro. Diagnóstico Maipú; ArgentinaFil: Leipsic, Jonathon A.. St. Paul's Hospital; CanadáFil: Capunay, Carlos. Diagnóstico Maipú; ArgentinaFil: De Zan, Macarena C.. Diagnóstico Maipú; ArgentinaFil: Goldsmit, Alejandro. Sanatorio Güemes; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Diagnóstico Maipú; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Cardiológicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiológicas; Argentin
Substantial iodine volume load reduction in CT angiography with dual-energy imaging: insights from a pilot randomized study
Full text linkWe explored whether dual-energy computed tomography (DECT) can allow a significant reduction in iodinated contrast volume during computed tomography angiography (CTA) without hampering image quality or assessibility. We prospectively randomized patients clinically referred to CTA to single energy computed tomography (SECT) with full iodine volume load (group A), DECT with 50 % iodine volume load (group B), DECT with 40 % iodine volume load (group C), and DECT with 30 % iodine volume load (group D); and compared image quality and assessibility. Eighty patients were enrolled and prospectively randomized. The mean age was 61.7 ± 15.0 years and 56 (71 %) patients were male. The demographical characteristics, body mass index, or mean radiation dose did not differ between groups. Significant reductions in total contrast volume were achieved in groups B, C, and D; with mean administrated contrast volumes of 90.3 ± 10.1, 39.5 ± 4.6, 28.3 ± 6.5, and 23.9 ± 6.0 mL, respectively, in groups A to D (p < 0.0001). With regard to image quality, no significant decrease in the Likert scale was observed with reductions of up to 60 % of the contrast volume (groups B and C). DECT at 50–60 keV in association with up to 60 % iodine load reduction, allowed similar signal density, image noise, and signal to noise ratio that SECT imaging with full iodine load. In this pilot, prospective, randomized study, dual energy CTA with up to 60 % iodine volume load reduction provided similar image quality and assessibility than full iodine load with conventional SECT imaging.Fil: Carrascosa, Patricia. Diagnostico Maipu; ArgentinaFil: Capunay, Carlos. Diagnostico Maipu; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Diagnostico Maipu; ArgentinaFil: Deviggiano, Alejandro. Diagnostico Maipu; ArgentinaFil: Vallejos, Javier. Diagnostico Maipu; ArgentinaFil: Leipsic, Jonathon A.. St. Paul’s Hospital; Canad
Optimal fluoroscopic viewing angles of right-sided heart structures in patients with tricuspid regurgitation based on multislice computed tomography.
No full textAIMS
This study sought to analyse multislice computed tomography (MSCT) data of patients with tricuspid regurgitation and to report the variability of fluoroscopic viewing angles for several right-sided heart structures, as well as chamber views of the right heart in order to determine the optimal fluoroscopic viewing angles of six right-sided heart structures and right-heart chamber views.
METHODS AND RESULTS
The MSCT data of 44 patients with mild to severe tricuspid regurgitation (TR) were retrospectively analysed. For each patient, we determined the optimal fluoroscopic viewing angles of the annulus/orifice en face view of the tricuspid valve, atrial septum, superior vena cava (SVC), inferior vena cava (IVC), coronary sinus (CS) and pulmonary valve. In this TR patient cohort, the average fluoroscopic viewing angle for the en face view of the tricuspid valve annulus was LAO 54-CAUD 15; RAO 10-CAUD 66 for the SVC orifice; LAO 27-CRA 59 for the IVC orifice; RAO 28-CRA 19 for the CS orifice; RAO 33-CAUD 33 for the atrial septum and LAO 13-CAUD 52 for the pulmonary valve annulus. The average viewing angle for right-heart chamber views was LAO 55-CAUD 15 for the one-chamber view; RAO 59-CAUD 54 for the two-chamber view; RAO 27-CRA 19 for the three-chamber view and LAO 5-CRA 60 for the four-chamber view.
CONCLUSIONS
MSCT can provide patient-specific fluoroscopic viewing angles of right-sided heart structures. This information may facilitate transcatheter right-heart interventions
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Virtual Monochromatic Imaging in Patients with Intermediate to High Likelihood of Coronary Artery Disease: Impact of Coronary Calcification
Full text linkRationale and Objectives
We sought to explore the image quality and diagnostic performance of virtual monochromatic imaging derived from dual-energy computed tomography coronary angiography (DE-CTCA) in patients with intermediate to high likelihood of coronary artery disease (CAD) and the influence of calcification.
Materials and Methods
Consecutive symptomatic patients with suspected CAD referred for invasive coronary angiography who underwent DE-CTCA and a coronary artery calcium scoring before the invasive procedure comprised the study population.
Results
Sixty-seven patients were included. Image quality was significantly lower at 45 keV reconstructions (mean Likert score 45 keV 3.57 ± 0.6, 65 keV 4.07 ± 0.5, and 85 keV 4.09 ± 0.6; P < .0001). Patients with moderate calcification showed a trend toward a significant improvement in the diagnostic performance with 65 keV vs 45 keV reconstructions (45 keV, area under the curve 0.92 [95% confidence interval 0.89–0.95] vs 65 keV, area under the curve 0.96 [95% confidence interval 0.93–0.98], P = .06). The diagnostic performance of DE-CTCA was significantly lower in segments with higher coronary artery calcium scoring compared to segments with none or mild calcification, independent of the energy level applied.
Conclusions
In patients with intermediate to high likelihood of CAD, DE-CTCA had a good diagnostic performance, although significantly lower in segments with severe calcification.Fil: Carrascosa, Patricia. Diagnóstico Maipú; ArgentinaFil: Leipsic, Jonathon A.. St. Paul's Hospital; CanadáFil: Deviggiano, Alejandro. Diagnóstico Maipú; ArgentinaFil: Capunay, Carlos. Diagnóstico Maipú; ArgentinaFil: Vallejos, Javier. Diagnóstico Maipú; ArgentinaFil: Goldsmit, Alejandro. Sanatorio Güemes; ArgentinaFil: De Zan, Macarena. Diagnóstico Maipú; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Diagnóstico Maipú; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Cardiológicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiológicas; Argentin
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