The aim of this study was to develop a computer model that accurately predicts myocardial fractional flow reserve (FFR) from angiographic images alone, in patients with coronary artery disease.
...Percutaneous coronary intervention (PCI) guided by FFR is superior to standard assessment alone. FFR-guided PCI results in improved clinical outcomes, a reduction in the number of stents implanted, and reduced cost. Currently FFR is used in few patients. A less invasive FFR would be a valuable tool.
Nineteen patients with stable coronary artery disease awaiting elective PCI were studied. They underwent rotational coronary angiography. The FFR was measured, physiologically significant lesions were stented, and angiography and FFR were repeated. Three-dimensional arterial anatomy pre- and post-stenting was reconstructed offline. Generic boundary conditions for computational fluid dynamics analysis were applied. The virtual fractional flow reserve (vFFR) and measured fractional flow reserve (mFFR) values were compared.
Thirty-five matched anatomical and physiological datasets were obtained: 10 right coronary arteries (RCA) (5 pre- and post-stenting), and 12 left coronary arteries (LCA) (8 pre- and post-stenting). The computational fluid dynamics model predicted which lesions were physiologically significant (FFR <0.80) and which were not (FFR >0.80) with accuracy, sensitivity, specificity, positive and negative predictive values of 97%, 86%, 100%, 100%, and 97% respectively. On average, the vFFR values deviated from mFFR by ±0.06 (mean delta = 0.02, SD = 0.08). The vFFR and mFFR were closely correlated (r = 0.84).
We have developed a model of intracoronary physiology based upon a rotational coronary angiogram. Significant lesions were identified with 97% accuracy. The FFR was reliably predicted without the need for invasive measurements or inducing hyperemia.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The main and interactive effects of biological maturity status and relative age upon self-regulation in male academy soccer players are considered. Consistent with the ‘underdog’ hypothesis, whereby ...relatively younger players may benefit from competitive play with older peers, it was predicted later maturing and/or relatively younger players would report more adaptive self-regulation.
Cross-sectional study.
Players (n = 171, aged 11–16 years) from four English professional soccer academies completed the modified Soccer Self-Regulation Scale. Date of birth, height, weight and parental height were obtained. Relative age was based on birth quarter for the selection year. Maturity status was based upon percentage of predicted adult height attained.
Linear regression models showed later maturation was inversely associated with adaptive self-regulation, while relative age was unrelated to self-regulation.
In partial support of the underdog hypothesis, later maturing players appear to possess a psychological advantage.
•Results of the present study partially support the ‘Underdog Hypothesis’. Although an apparent selection bias towards relatively older players was found, the results indicated no association between relative age and self-regulation.•Consistent with the 'underdog' hypothesis, later maturing players are more likely to possess and/or develop more adaptive self-regulation skills, in particular self-evaluation and reflection.•Exposing early maturing players to more challenging learning environments in soccer may facilitate the development of more adaptive psychological skill sets.•Soccer academies should focus on retaining late maturing players within the academy systems and challenging players who are advanced in maturation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Extract of a paper presented to the Spirituality in Health and Community Care conference at Stirling Management Centre, Scotland, on 15-16 November 2001
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