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1.
Nature ; 602(7896): 223-228, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35140384

RESUMEN

Many potential applications of artificial intelligence involve making real-time decisions in physical systems while interacting with humans. Automobile racing represents an extreme example of these conditions; drivers must execute complex tactical manoeuvres to pass or block opponents while operating their vehicles at their traction limits1. Racing simulations, such as the PlayStation game Gran Turismo, faithfully reproduce the non-linear control challenges of real race cars while also encapsulating the complex multi-agent interactions. Here we describe how we trained agents for Gran Turismo that can compete with the world's best e-sports drivers. We combine state-of-the-art, model-free, deep reinforcement learning algorithms with mixed-scenario training to learn an integrated control policy that combines exceptional speed with impressive tactics. In addition, we construct a reward function that enables the agent to be competitive while adhering to racing's important, but under-specified, sportsmanship rules. We demonstrate the capabilities of our agent, Gran Turismo Sophy, by winning a head-to-head competition against four of the world's best Gran Turismo drivers. By describing how we trained championship-level racers, we demonstrate the possibilities and challenges of using these techniques to control complex dynamical systems in domains where agents must respect imprecisely defined human norms.


Asunto(s)
Conducción de Automóvil , Aprendizaje Profundo , Refuerzo en Psicología , Deportes , Juegos de Video , Conducción de Automóvil/normas , Conducta Competitiva , Humanos , Recompensa , Deportes/normas
2.
Annu Rev Med ; 74: 189-198, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36318679

RESUMEN

The recent landmark International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial was undertaken to assess whether stable angina patients with moderate to severe baseline ischemia would benefit from an invasive approach with revascularization versus a conservative approach of intensive lifestyle intervention and pharmacologic secondary prevention. This trial addressed the hypothesis that treating ischemia with an invasive approach would reduce major adverse cardiac events more than a noninvasive pharmacologic and lifestyle approach. ISCHEMIA is discussed in detail, along with current implications for contemporary management of this very common cardiac disorder afflicting millions of patients worldwide.


Asunto(s)
Isquemia Miocárdica , Revascularización Miocárdica , Humanos , Isquemia Miocárdica/terapia , Isquemia/complicaciones , Resultado del Tratamiento
3.
Dev Sci ; 27(2): e13449, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37750490

RESUMEN

What is the optimal penalty for errors in infant skill learning? Behavioral analyses indicate that errors are frequent but trivial as infants acquire foundational skills. In learning to walk, for example, falling is commonplace but appears to incur only a negligible penalty. Behavioral data, however, cannot reveal whether a low penalty for falling is beneficial for learning to walk. Here, we used a simulated bipedal robot as an embodied model to test the optimal penalty for errors in learning to walk. We trained the robot to walk using 12,500 independent simulations on walking paths produced by infants during free play and systematically varied the penalty for falling-a level of precision, control, and magnitude impossible with real infants. When trained with lower penalties for falling, the robot learned to walk farther and better on familiar, trained paths and better generalized its learning to novel, untrained paths. Indeed, zero penalty for errors led to the best performance for both learning and generalization. Moreover, the beneficial effects of a low penalty were stronger for generalization than for learning. Robot simulations corroborate prior behavioral data and suggest that a low penalty for errors helps infants learn foundational skills (e.g., walking, talking, and social interactions) that require immense flexibility, creativity, and adaptability. RESEARCH HIGHLIGHTS: During infant skill acquisition, errors are commonplace but appear to incur a low penalty; when learning to walk, for example, falls are frequent but trivial. To test the optimal penalty for errors, we trained a simulated robot to walk using real infant paths and systematically manipulated the penalty for falling. Lower penalties in training led to better performance on familiar, trained paths and on novel untrained paths, and zero penalty was most beneficial. Benefits of a low penalty were stronger for untrained than for trained paths, suggesting that discounting errors facilitates acquiring skills that require immense flexibility and generalization.


Asunto(s)
Robótica , Lactante , Humanos , Accidentes por Caídas , Caminata , Aprendizaje , Generalización Psicológica
4.
J Physiol ; 601(23): 5391-5411, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37467072

RESUMEN

Fetal growth restriction (FGR) and maternal supine going-to-sleep position are both risk factors for late stillbirth. This study aimed to use magnetic resonance imaging (MRI) to quantify the effect of maternal supine position on maternal-placental and fetoplacental blood flow, placental oxygen transfer and fetal oxygenation in FGR and healthy pregnancies. Twelve women with FGR and 27 women with healthy pregnancies at 34-38 weeks' gestation underwent MRI in both left lateral and supine positions. Phase-contrast MRI and a functional MRI technique (DECIDE) were used to measure blood flow in the maternal internal iliac arteries (IIAs) and umbilical vein (UV), placental oxygen transfer (placental flux), fetal oxygen saturation (FO2 ), and fetal oxygen delivery (delivery flux). The presence of FGR, compared to healthy pregnancies, was associated with a 7.8% lower FO2 (P = 0.02), reduced placental flux, and reduced delivery flux. Maternal supine positioning caused a 3.8% reduction in FO2 (P = 0.001), and significant reductions in total IIA flow, placental flux, UV flow and delivery flux compared to maternal left lateral position. The effect of maternal supine position on fetal oxygen delivery was independent of FGR pregnancy, meaning that supine positioning has an additive effect of reducing fetal oxygenation further in women with FGR, compared to women with appropriately grown for age pregnancies. Meanwhile, the effect of maternal supine positioning on placental oxygen transfer was not independent of the effect of FGR. Therefore, growth-restricted fetuses, which are chronically hypoxaemic, experience a relatively greater decline in oxygen transfer when mothers lie supine in late gestation compared to appropriately growing fetuses. KEY POINTS: Fetal growth restriction (FGR) is the most common risk factor associated with stillbirth, and early recognition and timely delivery is vital to reduce this risk. Maternal supine going-to-sleep position is found to increase the risk of late stillbirth but when combined with having a FGR pregnancy, maternal supine position leads to 15 times greater odds of stillbirth compared to supine sleeping with appropriately grown for age (AGA) pregnancies. Using MRI, this study quantifies the chronic hypoxaemia experienced by growth-restricted fetuses due to 13.5% lower placental oxygen transfer and 26% lower fetal oxygen delivery compared to AGA fetuses. With maternal supine positioning, there is a 23% reduction in maternal-placental blood flow and a further 14% reduction in fetal oxygen delivery for both FGR and AGA pregnancies, but this effect is proportionally greater for growth-restricted fetuses. This knowledge emphasises the importance of avoiding supine positioning in late pregnancy, particularly for vulnerable FGR pregnancies.


Asunto(s)
Placenta , Circulación Placentaria , Embarazo , Femenino , Humanos , Placenta/diagnóstico por imagen , Placenta/irrigación sanguínea , Retardo del Crecimiento Fetal/diagnóstico por imagen , Mortinato , Imagen por Resonancia Magnética , Oxígeno
5.
J Physiol ; 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37432936

RESUMEN

Hypoxia-ischaemia (HI) before birth is a key risk factor for stillbirth and severe neurodevelopmental disability in survivors, including cerebral palsy, although there are no reliable biomarkers to detect at risk fetuses that may have suffered a transient period of severe HI. We investigated time and frequency domain measures of fetal heart rate variability (FHRV) for 3 weeks after HI in preterm fetal sheep at 0.7 gestation (equivalent to preterm humans) until 0.8 gestation (equivalent to term humans). We have previously shown that this is associated with delayed development of severe white and grey matter injury, including cystic white matter injury (WMI) resembling that observed in human preterm infants. HI was associated with suppression of time and frequency domain measures of FHRV and reduced their circadian rhythmicity during the first 3 days of recovery. By contrast, circadian rhythms of multiple measures of FHRV were exaggerated over the final 2 weeks of recovery, mediated by a greater reduction in FHRV during the morning nadir, but no change in the evening peak. These data suggest that the time of day at which FHRV measurements are taken affects their diagnostic utility. We further propose that circadian changes in FHRV may be a low-cost, easily applied biomarker of antenatal HI and evolving brain injury. KEY POINTS: Hypoxia-ischaemia (HI) before birth is a key risk factor for stillbirth and probably for disability in survivors, although there are no reliable biomarkers for antenatal brain injury. In preterm fetal sheep, acute HI that is known to lead to delayed development of severe white and grey matter injury over 3 weeks, was associated with early suppression of multiple time and frequency domain measures of fetal heart rate variability (FHRV) and loss of their circadian rhythms during the first 3 days after HI. Over the final 2 weeks of recovery after HI, exaggerated circadian rhythms of frequency domain FHRV measures were observed. The morning nadirs were lower with no change in the evening peak of FHRV. Circadian changes in FHRV may be a low-cost, easily applied biomarker of antenatal HI and evolving brain injury.

6.
Curr Opin Cardiol ; 38(6): 496-503, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37767898

RESUMEN

PURPOSE OF REVIEW: Major adverse cardiac events (MACE) typically arise from nonflow-limiting coronary artery disease and not from flow-limiting obstructions that cause ischemia. This review elaborates the current understanding of the mechanism(s) for plaque development, progression, and destabilization and how identification of these high-risk features can optimally inform clinical management. RECENT FINDINGS: Advanced invasive and noninvasive coronary imaging and computational postprocessing enhance an understanding of pathobiologic/pathophysiologic features of coronary artery plaques prone to destabilization and MACE. Early investigations of high-risk plaques focused on anatomic and biochemical characteristics (large plaque burden, severe luminal obstruction, thin cap fibroatheroma morphology, and large lipid pool), but more recent studies underscore that additional factors, particularly biomechanical factors [low endothelial shear stress (ESS), high ESS gradient, plaque structural stress, and axial plaque stress], provide the critical incremental stimulus acting on the anatomic substrate to provoke plaque destabilization. These destabilizing features are often located in areas distant from the flow-limiting obstruction or may exist in plaques without any flow limitation. Identification of these high-risk, synergistic plaque features enable identification of plaques prone to destabilize regardless of the presence or absence of a severe obstruction (Plaque Hypothesis). SUMMARY: Local plaque topography, hemodynamic patterns, and internal plaque constituents constitute high-risk features that may be located along the entire course of the coronary plaque, including both flow-limiting and nonflow-limiting regions. For coronary interventions to have optimal clinical impact, it will be critical to direct their application to the plaque area(s) at highest risk.


Asunto(s)
Enfermedad de la Arteria Coronaria , Placa Aterosclerótica , Humanos , Factores de Riesgo , Vasos Coronarios/diagnóstico por imagen , Hemodinámica
7.
Am J Obstet Gynecol ; 228(5S): S1117-S1128, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-34801443

RESUMEN

Uterine contractions during labor and engagement of the fetus in the birth canal can compress the fetal head. Its impact on the fetus is unclear and still controversial. In this integrative physiological review, we highlight evidence that decelerations are uncommonly associated with fetal head compression. Next, the fetus has an impressive ability to adapt to increased intracranial pressure through activation of the intracranial baroreflex, such that fetal cerebral perfusion is well-maintained during labor, except in the setting of prolonged systemic hypoxemia leading to secondary cardiovascular compromise. Thus, when it occurs, fetal head compression is not necessarily benign but does not seem to be a common contributor to intrapartum decelerations. Finally, the intracranial baroreflex and the peripheral chemoreflex (the response to acute hypoxemia) have overlapping efferent effects. We propose the hypothesis that these reflexes may work synergistically to promote fetal adaptation to labor.


Asunto(s)
Desaceleración , Trabajo de Parto , Embarazo , Femenino , Humanos , Parto , Trabajo de Parto/fisiología , Hipoxia , Feto/fisiología , Frecuencia Cardíaca Fetal/fisiología , Cardiotocografía
8.
Eur Heart J ; 43(2): 148-149, 2022 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-34514494

RESUMEN

AIMS: The International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trial prespecified an analysis to determine whether accounting for recurrent cardiovascular events in addition to first events modified understanding of the treatment effects. METHODS AND RESULTS: Patients with stable coronary artery disease (CAD) and moderate or severe ischaemia on stress testing were randomized to either initial invasive (INV) or initial conservative (CON) management. The primary outcome was a composite of cardiovascular death, myocardial infarction (MI), and hospitalization for unstable angina, heart failure, or cardiac arrest. The Ghosh-Lin method was used to estimate mean cumulative incidence of total events with death as a competing risk. The 5179 ISCHEMIA patients experienced 670 index events (318 INV, 352 CON) and 203 recurrent events (102 INV, 101 CON). A single primary event was observed in 9.8% of INV and 10.8% of CON patients while ≥2 primary events were observed in 2.5% and 2.8%, respectively. Patients with recurrent events were older; had more frequent hypertension, diabetes, prior MI, or cerebrovascular disease; and had more multivessel CAD. The average number of primary endpoint events per 100 patients over 4 years was 18.2 in INV [95% confidence interval (CI) 15.8-20.9] and 19.7 in CON (95% CI 17.5-22.2), difference -1.5 (95% CI -5.0 to 2.0, P = 0.398). Comparable results were obtained when all-cause death was substituted for cardiovascular death and when stroke was added as an event. CONCLUSIONS: In stable CAD patients with moderate or severe myocardial ischaemia enrolled in ISCHEMIA, an initial INV treatment strategy did not prevent either net recurrent events or net total events more effectively than an initial CON strategy. CLINICAL TRIAL REGISTRATION: ISCHEMIA ClinicalTrials.gov number, NCT01471522, https://clinicaltrials.gov/ct2/show/NCT01471522.


Asunto(s)
Enfermedad de la Arteria Coronaria , Isquemia Miocárdica , Angina Inestable , Tratamiento Conservador/métodos , Enfermedad de la Arteria Coronaria/terapia , Humanos , Isquemia , Isquemia Miocárdica/terapia
9.
Circulation ; 144(13): 1024-1038, 2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34496632

RESUMEN

BACKGROUND: The ISCHEMIA trial (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) postulated that patients with stable coronary artery disease (CAD) and moderate or severe ischemia would benefit from revascularization. We investigated the relationship between severity of CAD and ischemia and trial outcomes, overall and by management strategy. METHODS: In total, 5179 patients with moderate or severe ischemia were randomized to an initial invasive or conservative management strategy. Blinded, core laboratory-interpreted coronary computed tomographic angiography was used to assess anatomic eligibility for randomization. Extent and severity of CAD were classified with the modified Duke Prognostic Index (n=2475, 48%). Ischemia severity was interpreted by independent core laboratories (nuclear, echocardiography, magnetic resonance imaging, exercise tolerance testing, n=5105, 99%). We compared 4-year event rates across subgroups defined by severity of ischemia and CAD. The primary end point for this analysis was all-cause mortality. Secondary end points were myocardial infarction (MI), cardiovascular death or MI, and the trial primary end point (cardiovascular death, MI, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest). RESULTS: Relative to mild/no ischemia, neither moderate ischemia nor severe ischemia was associated with increased mortality (moderate ischemia hazard ratio [HR], 0.89 [95% CI, 0.61-1.30]; severe ischemia HR, 0.83 [95% CI, 0.57-1.21]; P=0.33). Nonfatal MI rates increased with worsening ischemia severity (HR for moderate ischemia, 1.20 [95% CI, 0.86-1.69] versus mild/no ischemia; HR for severe ischemia, 1.37 [95% CI, 0.98-1.91]; P=0.04 for trend, P=NS after adjustment for CAD). Increasing CAD severity was associated with death (HR, 2.72 [95% CI, 1.06-6.98]) and MI (HR, 3.78 [95% CI, 1.63-8.78]) for the most versus least severe CAD subgroup. Ischemia severity did not identify a subgroup with treatment benefit on mortality, MI, the trial primary end point, or cardiovascular death or MI. In the most severe CAD subgroup (n=659), the 4-year rate of cardiovascular death or MI was lower in the invasive strategy group (difference, 6.3% [95% CI, 0.2%-12.4%]), but 4-year all-cause mortality was similar. CONCLUSIONS: Ischemia severity was not associated with increased risk after adjustment for CAD severity. More severe CAD was associated with increased risk. Invasive management did not lower all-cause mortality at 4 years in any ischemia or CAD subgroup. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01471522.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/patología , Femenino , Humanos , Isquemia , Masculino , Resultado del Tratamiento
10.
Psychosom Med ; 84(3): 359-367, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35067655

RESUMEN

OBJECTIVE: Cardiac ischemia during daily life is associated with an increased risk of adverse outcomes. Mental stress is known to provoke cardiac ischemia and is related to psychological variables. In this multicenter cohort study, we assessed whether psychological characteristics were associated with ischemia in daily life. METHODS: This study examined patients with clinically stable coronary artery disease (CAD) with documented cardiac ischemia during treadmill exercise (n = 196, mean [standard deviation] age = 62.64 [8.31] years; 13% women). Daily life ischemia (DLI) was assessed by 48-hour ambulatory electrocardiophic monitoring. Psychological characteristics were assessed using validated instruments to identify characteristics associated with ischemia occurring in daily life stress. RESULTS: High scores on anger and hostility were common in this sample of patients with CAD, and DLI was documented in 83 (42%) patients. However, the presence of DLI was associated with lower anger scores (odds ratio [OR] = 2.03; 95% confidence interval [CI] = 1.12-3.69), reduced anger expressiveness (OR = 2.04; 95% CI = 1.10-3.75), and increased ratio of anger control to total anger (OR = 2.33; 95% CI = 1.27-4.17). Increased risk of DLI was also associated with lower hostile attribution (OR = 2.22; 95% CI = 1.21-4.09), hostile affect (OR = 1.92; 95% CI = 1.03-3.58), and aggressive responding (OR = 2.26; 95% CI = 1.25-4.08). We observed weak inverse correlations between DLI episode frequency and anger expressiveness, total anger, and hostility scores. DLI was not associated with depression or anxiety measures. The combination of the constructs low anger expressiveness and low hostile attribution was independently associated with DLI (OR = = 2.59; 95% CI = 1.42-4.72). CONCLUSIONS: In clinically stable patients with CAD, the tendency to suppress angry and hostile feelings, particularly openly aggressive behavior, was associated with DLI. These findings warrant a study in larger cohorts, and intervention studies are needed to ascertain whether management strategies that modify these psychological characteristics improve outcomes.


Asunto(s)
Enfermedad de la Arteria Coronaria , Isquemia Miocárdica , Ira , Estudios de Cohortes , Enfermedad de la Arteria Coronaria/complicaciones , Femenino , Hostilidad , Humanos , Isquemia/complicaciones , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/epidemiología , Isquemia Miocárdica/etiología , National Heart, Lung, and Blood Institute (U.S.) , Estrés Psicológico , Estados Unidos
11.
Arterioscler Thromb Vasc Biol ; 41(4): 1487-1503, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33567868
12.
Aust N Z J Obstet Gynaecol ; 62(1): 71-78, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34232517

RESUMEN

BACKGROUND: Severe maternal morbidity (SMM) occurs in 1-2% of pregnancies. Despite the knowledge that a SMM event can contribute to poor fetal/neonatal outcomes, little is known about the preventability of these adverse outcomes. AIMS: To examine adverse fetal/neonatal outcomes associated with SMM to determine if these outcomes were potentially preventable. MATERIALS AND METHODS: A New Zealand national retrospective cohort study examining cases of SMM with an adverse fetal/neonatal outcome. Maternity and initial neonatal care were explored by multidisciplinary panels utilising a preventability tool to assess whether the fetal/neonatal harm was potentially preventable. Adverse fetal/neonatal outcomes were defined as fetal or early neonatal death, Apgar score <7 at five minutes, admission to neonatal intensive care unit or special care baby unit and neonatal encephalopathy. RESULTS: Of 85 cases reviewed, adverse fetal/neonatal outcome was deemed potentially preventable in 55.3% of cases (n = 47/85). Preventability was related to maternal antenatal/peripartum care (in utero) in 39% (n = 33/85), to initial neonatal care (ex utero) in 36% (n = 29/80), and to both maternal and neonatal care in 20% (16/80) of cases. Main contributors to potential preventability were factors related to healthcare providers, particularly lack of recognition of high risk, delayed or failure to diagnose, and delayed or inappropriate treatment. CONCLUSIONS: Multidisciplinary panels found that over half of adverse fetal/neonatal harm associated with SMM was potentially preventable. The novel approach of examining both maternal and neonatal care identifies opportunities to improve fetal/neonatal outcomes associated with SMM at multiple points on the perinatal continuum of care.


Asunto(s)
Servicios de Salud Materna , Muerte Perinatal , Complicaciones del Embarazo , Femenino , Humanos , Lactante , Recién Nacido , Embarazo , Complicaciones del Embarazo/prevención & control , Atención Prenatal , Estudios Retrospectivos
13.
Cleft Palate Craniofac J ; 59(11): 1400-1412, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-34672811

RESUMEN

OBJECTIVE: To assess speech outcomes at five and ten years of age in a nationwide study of children with orofacial cleft. DESIGN: Prospective study. PARTICIPANTS: Children born with orofacial cleft and having primary surgery in New Zealand. Speech samples were available for 151 five-year-old, and 163 ten-year-old children. MAIN OUTCOME MEASURES: Intelligibility, Acceptability, Velopharyngeal function, Hypernasality, Hyponasality, severity of airflow evaluated by perceptual speech assessment (using the standardised Rhinocleft assessment), and overall assessment of requirement for clinical intervention. RESULTS: A large proportion of five-year-old children had speech that was considered to be not completely intelligible, was not acceptable, and had inadequate velopharyngeal function. The noted deficiencies led to a clinical judgement that further speech and/or surgical intervention was required in 85% with cleft lip and palate, 65% with cleft palate and 26% with cleft lip. The proportion of children with poor speech outcomes in the ten-year-old children was lower, though of clinical importance, further intervention required for 25% with CLP, 15% with CP and 3% with CL. The number of sound production errors in both age groups followed the same pattern with fewest in those with CL and most in those with CLP. CONCLUSIONS: A significant proportion of children with orofacial cleft were found to have poor speech outcomes requiring further treatment. The outcomes are poor compared to centres reported in the UK and Scandinavia. New Zealand requires a review of the current services for individuals born with cleft to improve speech outcomes and interdisciplinary care.


Asunto(s)
Labio Leporino , Fisura del Paladar , Insuficiencia Velofaríngea , Trastornos de la Voz , Niño , Preescolar , Labio Leporino/cirugía , Fisura del Paladar/cirugía , Humanos , Estudios Prospectivos , Habla , Trastornos del Habla , Inteligibilidad del Habla , Insuficiencia Velofaríngea/cirugía
14.
J Physiol ; 599(6): 1901-1915, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33369732

RESUMEN

KEY POINTS: Maternal supine sleep position in late pregnancy is associated with an increased risk of stillbirth. Maternal supine position in late pregnancy reduces maternal cardiac output and uterine blood flow. Using MRI, this study shows that compared to the left lateral position, maternal supine position in late pregnancy is associated with reduced utero-placental blood flow and oxygen transfer across the placenta with an average 6.2% reduction in oxygen delivery to the fetus and an average 11% reduction in fetal umbilical venous blood flow. ABSTRACT: Maternal sleep position in late gestation is associated with an increased risk of stillbirth, though the pathophysiological reasons for this are unclear. Studies using magnetic resonance imaging (MRI) have shown that compared with lateral positions, lying supine causes a reduction in cardiac output, reduced abdominal aortic blood flow and reduced vena caval flow which is only partially compensated for by increased flow in the azygos venous system. Using functional MRI techniques, including an acquisition termed diffusion-relaxation combined imaging of the placenta (DECIDE), which combines diffusion weighted imaging and T2 relaxometry, blood flow and oxygen transfer were estimated in the maternal, fetal and placental compartments when subjects were scanned both supine and in left lateral positions. In late gestation pregnancy, lying supine caused a 23.7% (P < 0.0001) reduction in total internal iliac arterial blood flow to the uterus. In addition, lying in the supine position caused a 6.2% (P = 0.038) reduction in oxygen movement across the placenta. The reductions in oxygen transfer to the fetus, termed delivery flux, of 11.2% (P = 0.0597) and in fetal oxygen saturation of 4.4% (P = 0.0793) did not reach statistical significance. It is concluded that even in healthy late gestation pregnancy, maternal position significantly affects oxygen transfer across the placenta and may in part provide an explanation for late stillbirth in vulnerable fetuses.


Asunto(s)
Imagen por Resonancia Magnética , Circulación Placentaria , Femenino , Feto/diagnóstico por imagen , Hemodinámica , Humanos , Placenta/diagnóstico por imagen , Embarazo , Tercer Trimestre del Embarazo
16.
Radiology ; 300(1): 79-86, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33973837

RESUMEN

Background Aortic valve calcification (AVC) is a key feature of aortic stenosis, and patients with aortic stenosis often have coronary -artery disease. Therefore, proving the association between the progression of AVC and coronary atherosclerosis could improve follow-up and treatment strategies. Purpose To explore the association between the progression of AVC and the progression of total and plaque volume composition from a large multicenter registry of serial coronary CT angiographic examinations. Materials and Methods A prospective multinational registry (PARADIGM) of consecutive participants who underwent serial coronary CT angiography at intervals of every 2 years or more was performed (January 2003-December 2015). AVC and the total and plaque volume composition at baseline and follow-up angiography were quantitatively analyzed. Plaque volumes were normalized by using the mean total analyzed vessel length of the study population. Multivariable linear mixed-effects models were constructed. Results Overall, 594 participants (mean age ± standard deviation, 62 years ± 10; 330 men) were included (mean interval between baseline and follow-up angiography, 3.9 years ± 1.5). At baseline, the AVC score was 31 Agatston units ± 117, and the normalized total plaque volume at baseline was 122 mm3 ± 219. After adjustment for age, sex, clinical risk factors, and medication use, AVC was independently associated with total plaque volume (standardized ß = 0.24; 95% CI: 0.16, 0.32; P < .001) and both calcified (ß = 0.26; 95% CI: 0.18, 0.34; P < .001) and noncalcified (ß = 0.17; 95% CI: 0.08, 0.25; P < .001) plaque volumes at baseline. The progression of AVC was associated with the progression of total plaque volume (ß = 0.13; 95% CI: 0.03, 0.22; P = .01), driven solely by calcified plaque volume (ß = 0.24; 95% CI: 0.14, 0.34; P < .001) but not noncalcified plaque volumes (ß = -0.06; 95% CI: -0.14, 0.03; P = .17). Conclusion The overall burden of coronary atherosclerosis was associated with aortic valve calcification at baseline. However, the progression of aortic valve calcification was associated with only the progression of calcified plaque volume but not with the -progression of noncalcified plaque volume. Clinical trial registration no. NCT02803411 © RSNA, 2021 See also the editorial by Sinitsyn in this issue.


Asunto(s)
Estenosis de la Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/patología , Calcinosis/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Placa Aterosclerótica/diagnóstico por imagen , Sistema de Registros/estadística & datos numéricos , Anciano , Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/complicaciones , Calcinosis/complicaciones , Enfermedad de la Arteria Coronaria/complicaciones , Progresión de la Enfermedad , Femenino , Humanos , Internacionalidad , Masculino , Persona de Mediana Edad , Placa Aterosclerótica/complicaciones , Estudios Prospectivos
17.
Eur J Clin Invest ; 51(2): e13380, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33368197

RESUMEN

BACKGROUND: The clustering of arterial stiffness with microvascular disease (MD) and their effects on the clinical outcome of patients with type 2 diabetes (T2D) remains not fully clarified. METHODS: In a prospective study of 414 patients with T2D, we investigated the prognostic value of arterial stiffness and MD for clinical outcomes. Participants were assessed for the presence of MD (ie diabetic retinopathy, nephropathy and neuropathy) and arterial stiffness by pulse wave velocity (PWV) and followed-up for a median of 30 (range 1-60) months. The primary endpoint of the study was the composite endpoint of major adverse cardiovascular events, that is, cardiovascular and non-cardiovascular mortality and non-fatal myocardial infarction/stroke. RESULTS: A total of 146 (35.3%) patients had evidence of MD at baseline. In cox regression models, MD and PWV were independently associated with the composite clinical endpoint; for MD hazard ratio (HR), 3.24, 95%CI, 1.10-9.54, P=.032, and for PWV HR, 1.20, 95%CI, 1.06-1.36, P=.004) after adjustment for traditional risk factors, and enhanced risk discrimination and reclassification. The subgroup of patients with MD and high PWV was associated with increased incidence of the composite clinical endpoint (20.9% vs 1.8% in those with no MD & low PWV, P=.001). Importantly, absence of MD at baseline was associated with no mortality events during the follow-up period. PWV at baseline was not associated with MD progression during follow-up. CONCLUSIONS: These findings support that screening for arterial stiffness and MD in the routine clinical assessment of patients with T2D may enhance prognostication and cardiovascular risk reclassification.


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Nefropatías Diabéticas/fisiopatología , Neuropatías Diabéticas/fisiopatología , Retinopatía Diabética/fisiopatología , Rigidez Vascular/fisiología , Anciano , Enfermedades Cardiovasculares/mortalidad , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Nefropatías Diabéticas/epidemiología , Nefropatías Diabéticas/etiología , Neuropatías Diabéticas/epidemiología , Neuropatías Diabéticas/etiología , Retinopatía Diabética/epidemiología , Retinopatía Diabética/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mortalidad , Infarto del Miocardio/epidemiología , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Análisis de la Onda del Pulso , Accidente Cerebrovascular/epidemiología
18.
Eur Heart J ; 41(31): 2997-3004, 2020 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-32402086

RESUMEN

Despite advanced understanding of the biology of atherosclerosis, coronary heart disease remains the leading cause of death worldwide. Progress has been challenging as half of the individuals who suffer sudden cardiac death do not experience premonitory symptoms. Furthermore, it is well-recognized that also a plaque that does not cause a haemodynamically significant stenosis can trigger a sudden cardiac event, yet the majority of ruptured or eroded plaques remain clinically silent. In the past 30 years since the term 'vulnerable plaque' was introduced, there have been major advances in the understanding of plaque pathogenesis and pathophysiology, shifting from pursuing features of 'vulnerability' of a specific lesion to the more comprehensive goal of identifying patient 'cardiovascular vulnerability'. It has been also recognized that aside a thin-capped, lipid-rich plaque associated with plaque rupture, acute coronary syndromes (ACS) are also caused by plaque erosion underlying between 25% and 60% of ACS nowadays, by calcified nodule or by functional coronary alterations. While there have been advances in preventive strategies and in pharmacotherapy, with improved agents to reduce cholesterol, thrombosis, and inflammation, events continue to occur in patients receiving optimal medical treatment. Although at present the positive predictive value of imaging precursors of the culprit plaques remains too low for clinical relevance, improving coronary plaque imaging may be instrumental in guiding pharmacotherapy intensity and could facilitate optimal allocation of novel, more aggressive, and costly treatment strategies. Recent technical and diagnostic advances justify continuation of interdisciplinary research efforts to improve cardiovascular prognosis by both systemic and 'local' diagnostics and therapies. The present state-of-the-art document aims to present and critically appraise the latest evidence, developments, and future perspectives in detection, prevention, and treatment of 'high-risk' plaques occurring in 'vulnerable' patients.


Asunto(s)
Síndrome Coronario Agudo , Aterosclerosis , Enfermedad de la Arteria Coronaria , Enfermedad Coronaria , Placa Aterosclerótica , Muerte Súbita Cardíaca/etiología , Muerte Súbita Cardíaca/prevención & control , Humanos , Placa Aterosclerótica/diagnóstico por imagen
19.
Cleft Palate Craniofac J ; 58(8): 1040-1046, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33325268

RESUMEN

OBJECTIVES: To describe (1) oral health related quality of life (OHRQoL) for children with orofacial cleft (OFC) in New Zealand and (2) assess any differences in OHRQoL by sex, ethnicity, and cleft phenotype using the 16 item (and 8 item subset) of the Child Perception Questionnaire (CPQ) and Parent version (P-CPQ). DESIGN AND SETTING: Prospective cross-sectional nationwide study. METHODS AND MATERIALS: Children with OFC and their parents completed the 16-item CPQ or the Parent CPQ, respectively, when attending cleft clinic appointments between January 2015 and December 2017. RESULTS: Overall, 174 children (mean age 10.4 ± 1.2 years) and their parents (n = 181) completed the CPQ or P-CPQ. In multivariable analysis, neither the CPQ nor P-CPQ 16-item or 8-item subset showed significant differences in OHRQoL total score with cleft phenotype. Children with cleft lip and palate (CLP) had higher (worse) well-being scores than those with cleft palate alone (CP) on the P-CPQ. Pacific Island children had consistently higher scores across both CPQ and P-CPQ, total and subscales. CONCLUSIONS: Significant differences in OHRQoL among children with OFC were found for the well-being domain for children with CLP as reported by P-CPQ, but the symptom domain and total score showed no differences. Poorer scores were reported for children of Pacific Island descent using both questionnaires. The study findings indicate that children with OFC in New Zealand are a group who experience worse OHRQoL when referenced to normative non-OFC data. Further investigations are required to establish greater insight into specific factors influencing OHRQoL.


Asunto(s)
Labio Leporino , Fisura del Paladar , Niño , Estudios Transversales , Humanos , Nueva Zelanda , Salud Bucal , Estudios Prospectivos , Calidad de Vida , Encuestas y Cuestionarios
20.
Cleft Palate Craniofac J ; 58(8): 1032-1039, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33233931

RESUMEN

OBJECTIVE: To determine whether children with an orofacial cleft have higher levels of behavioral problems than the general population and whether this differs by cleft phenotype. DESIGN: A cohort of children with cleft lip and/or palate (CL/P) born in New Zealand from January 1, 2000. SETTING: Cleft clinics in New Zealand participating in a larger outcomes study between 2014 and 2017. PARTICIPANTS: Children (N = 378) aged 5 to 12 years of age and their parents. MAIN OUTCOMES: The Strengths and Difficulties Questionnaire (SDQ) and Pediatric Quality of Life Inventory (PedsQL) Generic Core Scales 4.0 and Family Impact Module 2.0. RESULTS: Compared to standardized norms, children with a cleft had higher than expected (defined as 20%) levels of abnormal/borderline SDQ scores for conduct problems (27.4%, P = .0003) and peer relationship problems (31.6%, P < .0001) but lower than expected levels of problems with pro-social skills (6.3%, P < .0001). There were no significant differences by age-group and or cleft phenotype other than an increased risk of hyperactivity in children with CP compared to children with CL. Total difficulties SDQ scores had moderate correlations with the PedsQL. CONCLUSIONS: While over 90% of children with CL/P had normal prosocial skills, they may not be easily accepted by their peers which may result in behavioral problems. These concerns were moderately related to lower quality of life. Support for establishment and maintenance of peer relationships is important to address externalizing and peer difficulties in children with CL/P. Community knowledge and understanding of CL/P needs to continue to be promoted.


Asunto(s)
Labio Leporino , Fisura del Paladar , Niño , Humanos , Nueva Zelanda/epidemiología , Padres , Calidad de Vida , Encuestas y Cuestionarios
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