32 results on '"Sanghvi, Mihir"'
Search Results
2. Genome-wide association analysis reveals insights into the genetic architecture of right ventricular structure and function
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Aung, Nay, Vargas, Jose D., Yang, Chaojie, Fung, Kenneth, Sanghvi, Mihir M., Piechnik, Stefan K., Neubauer, Stefan, Manichaikul, Ani, Rotter, Jerome I., Taylor, Kent D., Lima, Joao A. C., Bluemke, David A., Kawut, Steven M., Petersen, Steffen E., and Munroe, Patricia B.
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- 2022
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3. Tissue-tracking in the assessment of late gadolinium enhancement in myocarditis and myocardial infarction
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Doimo, Sara, Ricci, Fabrizio, Aung, Nay, Cooper, Jackie, Boubertakh, Redha, Sanghvi, Mihir M., Sinagra, Gianfranco, and Petersen, Steffen E.
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- 2020
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4. Quantitative CMR population imaging on 20,000 subjects of the UK Biobank imaging study: LV/RV quantification pipeline and its evaluation
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Attar, Rahman, Pereañez, Marco, Gooya, Ali, Albà, Xènia, Zhang, Le, de Vila, Milton Hoz, Lee, Aaron M., Aung, Nay, Lukaschuk, Elena, Sanghvi, Mihir M., Fung, Kenneth, Paiva, Jose Miguel, Piechnik, Stefan K., Neubauer, Stefan, Petersen, Steffen E., and Frangi, Alejandro F.
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- 2019
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5. Cardiovascular magnetic resonance imaging for amyloidosis: The state-of-the-art
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Tang, Chun Xiang, Petersen, Steffen E., Sanghvi, Mihir M., Lu, Guang Ming, and Zhang, Long Jiang
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- 2019
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6. A history of cardiovascular magnetic resonance imaging in clinical practice and population science.
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Sanghvi, Mihir M., Lima, João A. C., Bluemke, David A., and Petersen, Steffen E.
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- 2024
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7. Independent Left Ventricular Morphometric Atlases Show Consistent Relationships with Cardiovascular Risk Factors: A UK Biobank Study
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Gilbert, Kathleen, Bai, Wenjia, Mauger, Charlene, Medrano-Gracia, Pau, Suinesiaputra, Avan, Lee, Aaron M., Sanghvi, Mihir M., Aung, Nay, Piechnik, Stefan K., Neubauer, Stefan, Petersen, Steffen E., Rueckert, Daniel, and Young, Alistair A.
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- 2019
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8. Prognostic Significance of Left Ventricular Noncompaction: Systematic Review and Meta-Analysis of Observational Studies
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Aung, Nay, Doimo, Sara, Ricci, Fabrizio, Sanghvi, Mihir M., Pedrosa, Cesar, Woodbridge, Simon P., Al-Balah, Amer, Zemrak, Filip, Khanji, Mohammed Y., Munroe, Patricia B., Naci, Huseyin, and Petersen, Steffen E.
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- 2020
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9. Concurrent Left Ventricular Myocardial Diffuse Fibrosis and Left Atrial Dysfunction Strongly Predict Incident Heart Failure.
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Wong, Mark Y.Z., Vargas, Jose D., Naderi, Hafiz, Sanghvi, Mihir M., Raisi-Estabragh, Zahra, Suinesiaputra, Avan, Bonazzola, Rodrigo, Attar, Rahman, Ravikumar, Nishant, Hann, Evan, Neubauer, Stefan, Piechnik, Stefan K., Frangi, Alejandro F., Petersen, Steffen E., and Aung, Nay
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- 2024
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10. 3.2 First Genome-Wide Association Study of Cardiovascular Magnetic Resonance Derived Aortic Distensibility Reveals 7 Loci
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Fung, Kenneth, Biasiolli, Luca, Hann, Evan, Ramirez, Julia, Lukaschuk, Elena, Aung, Nay, Paiva, Jose, Werys, Konrad, Sanghvi, Mihir, Thomson, Ross, Rayner, Jennifer, Puchta, Henrike, Moon, Niall, Thomas, Katharine, Lee, Aaron, Piechnik, Stefan, Neubauer, Stefan, Petersen, Steffen, and Munroe, Patricia
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- 2019
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11. Changes in Cardiac Morphology and Function in Individuals With Diabetes Mellitus: The UK Biobank Cardiovascular Magnetic Resonance Substudy
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Jensen, Magnus T., Fung, Kenneth, Aung, Nay, Sanghvi, Mihir M., Chadalavada, Sucharitha, Paiva, Jose M., Khanji, Mohammed Y., de Knegt, Martina C., Lukaschuk, Elena, Lee, Aaron M., Barutcu, Ahmet, Maclean, Edd, Carapella, Valentina, Cooper, Jackie, Young, Alistair, Piechnik, Stefan K., Neubauer, Stefan, and Petersen, Steffen E.
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- 2019
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12. Right ventricular shape and function: cardiovascular magnetic resonance reference morphology and biventricular risk factor morphometrics in UK Biobank
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Mauger, Charlène, Gilbert, Kathleen, Lee, Aaron M., Sanghvi, Mihir M., Aung, Nay, Fung, Kenneth, Carapella, Valentina, Piechnik, Stefan K., Neubauer, Stefan, Petersen, Steffen E., Suinesiaputra, Avan, and Young, Alistair A.
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- 2019
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13. Automated quality control in image segmentation: application to the UK Biobank cardiovascular magnetic resonance imaging study
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Robinson, Robert, Valindria, Vanya V., Bai, Wenjia, Oktay, Ozan, Kainz, Bernhard, Suzuki, Hideaki, Sanghvi, Mihir M., Aung, Nay, Paiva, José Miguel, Zemrak, Filip, Fung, Kenneth, Lukaschuk, Elena, Lee, Aaron M., Carapella, Valentina, Kim, Young Jin, Piechnik, Stefan K., Neubauer, Stefan, Petersen, Steffen E., Page, Chris, Matthews, Paul M., Rueckert, Daniel, and Glocker, Ben
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- 2019
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14. Automated cardiovascular magnetic resonance image analysis with fully convolutional networks
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Bai, Wenjia, Sinclair, Matthew, Tarroni, Giacomo, Oktay, Ozan, Rajchl, Martin, Vaillant, Ghislain, Lee, Aaron M., Aung, Nay, Lukaschuk, Elena, Sanghvi, Mihir M., Zemrak, Filip, Fung, Kenneth, Paiva, Jose Miguel, Carapella, Valentina, Kim, Young Jin, Suzuki, Hideaki, Kainz, Bernhard, Matthews, Paul M., Petersen, Steffen E., Piechnik, Stefan K., Neubauer, Stefan, Glocker, Ben, and Rueckert, Daniel
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- 2018
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15. Sex-specific associations between alcohol consumption, cardiac morphology, and function as assessed by magnetic resonance imaging: insights form the UK Biobank Population Study.
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Simon, Judit, Fung, Kenneth, Kolossváry, Márton, Sanghvi, Mihir M., Aung, Nay, Paiva, Jose Miguel, Lukaschuk, Elena, Carapella, Valentina, Merkely, Béla, Bittencourt, Marcio S., Karády, Júlia, Lee, Aaron M., Piechnik, Stefan K., Neubauer, Stefan, Maurovich-Horvat, Pál, and Petersen, Steffen E.
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HEART anatomy ,HEART radiography ,HEART physiology ,CONFIDENCE intervals ,MULTIVARIATE analysis ,MAGNETIC resonance imaging ,REGRESSION analysis ,ALCOHOL drinking ,DESCRIPTIVE statistics ,DATA analysis software ,LONGITUDINAL method - Abstract
Aims Data regarding the effects of regular alcohol consumption on cardiac anatomy and function are scarce. Therefore, we sought to determine the relationship between regular alcohol intake and cardiac structure and function as evaluated with cardiac magnetic resonance imaging. Methods and results Participants of the UK Biobank who underwent cardiac magnetic resonance were enrolled in our analysis. Data regarding regular alcohol consumption were obtained from questionnaires filled in by the study participants. Exclusion criteria were poor image quality, missing, or incongruent data regarding alcohol drinking habits, prior drinking, presence of heart failure or angina, and prior myocardial infarction or stroke. Overall, 4335 participants (61.5 ± 7.5 years, 47.6% male) were analysed. We used multivariate linear regression models adjusted for age, ethnicity, body mass index, smoking, hypertension, diabetes mellitus, physical activity, cholesterol level, and Townsend deprivation index to examine the relationship between regular alcohol intake and cardiac structure and function. In men, alcohol intake was independently associated with marginally increased left ventricular end-diastolic volume [ β = 0.14; 95% confidence interval (CI) = 0.05–0.24; P = 0.004], left ventricular stroke volume (β = 0.08; 95% CI = 0.03–0.14; P = 0.005), and right ventricular stroke volume (β = 0.08; 95% CI = 0.02–0.13; P = 0.006). In women, alcohol consumption was associated with increased left atrium volume (β = 0.14; 95% CI = 0.04–0.23; P = 0.006). Conclusion Alcohol consumption is independently associated with a marginal increase in left and right ventricular volumes in men, but not in women, whereas alcohol intake showed an association with increased left atrium volume in women. Our results suggest that there is only minimal relationship between regular alcohol consumption and cardiac morphology and function in an asymptomatic middle-aged population. [ABSTRACT FROM AUTHOR]
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- 2021
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16. Subclinical Changes in Cardiac Functional Parameters as Determined by Cardiovascular Magnetic Resonance (CMR) Imaging in Sleep Apnea and Snoring: Findings from UK Biobank.
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Curta, Adrian, Hetterich, Holger, Schinner, Regina, Lee, Aaron M., Sommer, Wieland, Aung, Nay, Sanghvi, Mihir M., Fung, Kenneth, Lukaschuk, Elena, Cooper, Jackie A., Paiva, José Miguel, Carapella, Valentina, Neubauer, Stefan, Piechnik, Stefan K., and Petersen, Steffen E.
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CARDIOVASCULAR system ,SLEEP apnea syndromes ,MAGNETIC resonance imaging ,SNORING ,VENTRICULAR dysfunction - Abstract
Background and Objectives: Obstructive sleep apnea (OSA) is a common disorder with an increased risk for left ventricular and right ventricular dysfunction. Most studies to date have examined populations with manifest cardiovascular disease using echocardiography to analyze ventricular dysfunction with little or no reference to ventricular volumes or myocardial mass. Our aim was to explore these parameters with cardiac MRI. We hypothesized that there would be stepwise increase in left ventricular mass and right ventricular volumes from the unaffected, to the snoring and the OSA group. Materials and Methods: We analyzed cardiac MRI data from 4978 UK Biobank participants free from cardiovascular disease. Participants were allocated into three cohorts: with OSA, with self-reported snoring and without OSA or snoring (n = 118, 1886 and 2477). We analyzed cardiac parameters from balanced cine-SSFP sequences and indexed them to body surface area. Results: Patients with OSA were mostly males (47.3% vs. 79.7%; p < 0.001) with higher body mass index (25.7 ± 4.0 vs. 31.3 ± 5.3 kg/m²; p < 0.001) and higher blood pressure (135 ± 18 vs. 140 ± 17 mmHg; p = 0.012) compared to individuals without OSA or snoring. Regression analysis showed a significant effect for OSA in left ventricular end-diastolic index (LVEDVI) (β = −4.9 ± 2.4 mL/m²; p = 0.040) and right ventricular end-diastolic index (RVEDVI) (β = −6.2 ± 2.6 mL/m²; p = 0.016) in females and for right ventricular ejection fraction (RVEF) (β = 1.7 ± 0.8%; p = 0.031) in males. A significant effect was discovered in snoring females for left ventricular mass index (LVMI) (β = 3.5 ± 0.9 g/m²; p < 0.001) and in males for left ventricular ejection fraction (LVEF) (β = 1.0 ± 0.3%; p = 0.001) and RVEF (β = 1.2 ± 0.3%; p < 0.001). Conclusion: Our study suggests that OSA is highly underdiagnosed and that it is an evolving process with gender specific progression. Females with OSA show significantly lower ventricular volumes while males with snoring show increased ejection fractions which may be an early sign of hypertrophy. Separate prospective studies are needed to further explore the direction of causality. [ABSTRACT FROM AUTHOR]
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- 2021
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17. Poor Bone Quality is Associated With Greater Arterial Stiffness: Insights From the UK Biobank.
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Raisi‐Estabragh, Zahra, Biasiolli, Luca, Cooper, Jackie, Aung, Nay, Fung, Kenneth, Paiva, José M, Sanghvi, Mihir M, Thomson, Ross J, Curtis, Elizabeth, Paccou, Julien, Rayner, Jennifer J, Werys, Konrad, Puchta, Henrike, Thomas, Katharine E, Lee, Aaron M, Piechnik, Stefan K, Neubauer, Stefan, Munroe, Patricia B, Cooper, Cyrus, and Petersen, Steffen E
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Osteoporosis and ischemic heart disease (IHD) represent important public health problems. Existing research suggests an association between the two conditions beyond that attributable to shared risk factors, with a potentially causal relationship. In this study, we tested the association of bone speed of sound (SOS) from quantitative heel ultrasound with (i) measures of arterial compliance from cardiovascular magnetic resonance (aortic distensibility [AD]); (ii) finger photoplethysmography (arterial stiffness index [ASI]); and (iii) incident myocardial infarction and IHD mortality in the UK Biobank cohort. We considered the potential mediating effect of a range of blood biomarkers and cardiometabolic morbidities and evaluated differential relationships by sex, menopause status, smoking, diabetes, and obesity. Furthermore, we considered whether associations with arterial compliance explained association of SOS with ischemic cardiovascular outcomes. Higher SOS was associated with lower arterial compliance by both ASI and AD for both men and women. The relationship was most consistent with ASI, likely relating to larger sample size available for this variable (n = 159,542 versus n = 18,229). There was no clear evidence of differential relationship by menopause, smoking, diabetes, or body mass index (BMI). Blood biomarkers appeared important in mediating the association for both men and women, but with different directions of effect and did not fully explain the observed effects. In fully adjusted models, higher SOS was associated with significantly lower IHD mortality in men, but less robustly in women. The association of SOS with ASI did not explain this observation. In conclusion, our findings support a positive association between bone and vascular health with consistent patterns of association in men and women. The underlying mechanisms are complex and appear to vary by sex. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). [ABSTRACT FROM AUTHOR]
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- 2021
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18. The Effect of Blood Lipids on the Left Ventricle: A Mendelian Randomization Study.
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Aung, Nay, Sanghvi, Mihir M, Piechnik, Stefan K, Neubauer, Stefan, Munroe, Patricia B, and Petersen, Steffen E
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TRIGLYCERIDES , *RESEARCH , *RESEARCH methodology , *LDL cholesterol , *MAGNETIC resonance imaging , *EVALUATION research , *MEDICAL cooperation , *HEART ventricles , *COMPARATIVE studies , *RESEARCH funding , *LONGITUDINAL method - Abstract
Background: Cholesterol and triglycerides are among the most well-known risk factors for cardiovascular disease.Objectives: This study investigated whether higher low-density lipoprotein (LDL) cholesterol and triglyceride levels and lower high-density lipoprotein cholesterol level are causal risk factors for changes in prognostically important left ventricular (LV) parameters.Methods: One-sample Mendelian randomization (MR) of 17,311 European individuals from the UK Biobank with paired lipid and cardiovascular magnetic resonance data was performed. Two-sample MR was performed by using summary-level data from the Global Lipid Genetics Consortium (n = 188,577) and UK Biobank Cardiovascular Magnetic Resonance substudy (n = 16,923) for sensitivity analyses.Results: In 1-sample MR analysis, higher LDL cholesterol was causally associated with higher LV end-diastolic volume (β = 1.85 ml; 95% confidence interval [CI]: 0.59 to 3.14 ml; p = 0.004) and higher LV mass (β = 0.81 g; 95% CI: 0.11 to 1.51 g; p = 0.023) and triglycerides with higher LV mass (β = 1.37 g; 95% CI: 0.45 to 2.3 g; p = 0.004). High-density lipoprotein cholesterol had no significant association with any LV parameter. Similar results were obtained by using 2-sample MR. Observational analyses were frequently discordant with those derived from MR.Conclusions: MR analysis demonstrates that LDL cholesterol and triglycerides are associated with adverse changes in cardiac structure and function, in particular in relation to LV mass. These findings suggest that LDL cholesterol and triglycerides may have a causal effect in influencing cardiac morphology in addition to their established role in atherosclerosis. [ABSTRACT FROM AUTHOR]- Published
- 2020
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19. Pulmonary blood volume index as a quantitative biomarker of haemodynamic congestion in hypertrophic cardiomyopathy.
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Ricci, Fabrizio, Aung, Nay, Thomson, Ross, Boubertakh, Redha, Camaioni, Claudia, Doimo, Sara, Sanghvi, Mihir M, Fung, Kenneth, Khanji, Mohammed Y, Lee, Aaron, Malcolmson, James, Mantini, Cesare, Paiva, José, Gallina, Sabina, Fedorowski, Artur, Mohiddin, Saidi A, Aquaro, Giovanni Donato, and Petersen, Steffen E
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HEART ventricle diseases ,BIOMARKERS ,BLOOD pressure ,BLOOD volume ,COMPARATIVE studies ,CONFIDENCE intervals ,CARDIAC hypertrophy ,LEFT heart ventricle ,RIGHT heart ventricle ,HEART atrium ,HEART failure ,HEMODYNAMICS ,MAGNETIC resonance imaging ,PULMONARY circulation ,TRANSESOPHAGEAL echocardiography ,MULTIPLE regression analysis ,DESCRIPTIVE statistics ,STROKE volume (Cardiac output) ,LEFT heart atrium ,ODDS ratio - Abstract
Aims The non-invasive assessment of left ventricular (LV) diastolic function and filling pressure in hypertrophic cardiomyopathy (HCM) is still an open issue. Pulmonary blood volume index (PBVI) by cardiovascular magnetic resonance (CMR) has been proposed as a quantitative biomarker of haemodynamic congestion. We aimed to assess the diagnostic accuracy of PBVI for left atrial pressure (LAP) estimation in patients with HCM. Methods and results We retrospectively identified 69 consecutive HCM outpatients (age 58 ± 11 years; 83% men) who underwent both transthoracic echocardiography (TTE) and CMR. Guideline-based detection of LV diastolic dysfunction was assessed by TTE, blinded to CMR results. PBVI was calculated as the product of right ventricular stroke volume index and the number of cardiac cycles for a bolus of gadolinium to pass through the pulmonary circulation as assessed by first-pass perfusion imaging. Compared to patients with normal LAP, patients with increased LAP showed significantly larger PBVI (463 ± 127 vs. 310 ± 86 mL/m
2 , P < 0.001). PBVI increased progressively with worsening New York Heart Association functional class and echocardiographic stages of diastolic dysfunction (P < 0.001 for both). At the best cut-off point of 413 mL/m2 , PBVI yielded good diagnostic accuracy for the diagnosis of LV diastolic dysfunction with increased LAP [C-statistic = 0.83; 95% confidence interval (CI): 0.73–0.94]. At multivariable logistic regression analysis, PBVI was an independent predictor of increased LAP (odds ratio per 10% increase: 1.97, 95% CI: 1.06–3.68; P = 0.03). Conclusion PBVI is a promising CMR application for assessment of diastolic function and LAP in patients with HCM and may serve as a quantitative marker for detection, grading, and monitoring of haemodynamic congestion. [ABSTRACT FROM AUTHOR]- Published
- 2019
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20. Does self-reported pregnancy loss identify women at risk of an adverse cardiovascular phenotype in later life? Insights from UK Biobank.
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Elmahi, Einas, Sanghvi, Mihir M., Jones, Alexander, Aye, Christina Y. L., Lewandowski, Adam J., Aung, Nay, Cooper, Jackie A., Paiva, José Miguel, Lukaschuk, Elena, Piechnik, Stefan K., Neubauer, Stefan, Petersen, Steffen E., and Leeson, Paul
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PREGNANCY complications , *PREGNANCY , *VASCULAR remodeling , *CAROTID intima-media thickness , *CAROTID artery , *MISCARRIAGE - Abstract
Cardiovascular disease (CVD) is more common in women who have had pregnancy complications such as spontaneous pregnancy loss. We used cross-sectional data from the UK Biobank Imaging Enhancement Study to determine whether pregnancy loss is associated with cardiac or vascular remodelling in later life, which might contribute to this increased risk. Pregnancy history was reported by women participating in UK Biobank between 2006 and 2010 at age 40–69 years using a self-completed touch-screen questionnaire. Associations between self-reported spontaneous pregnancy loss and cardiovascular measures, collected in women who participated in the Imaging Enhancement Study up to the end of 2015, were examined. Cardiac structure and function were assessed by magnetic resonance (CMR) steady-state free precession imaging at 1.5 Tesla. Carotid intima-media thickness (CIMT) measurements were taken for both common carotid arteries using a CardioHealth Station. Statistical associations with CMR and carotid measures were adjusted for age, BMI and other cardiovascular risk factors. Data were available on 2660 women of whom 111 were excluded because of pre-existing cardiovascular disease and 30 had no pregnancy information available. Of the remaining 2519, 446 were nulligravid and 2073 had a history of pregnancies, of whom 622 reported at least one pregnancy loss (92% miscarriages and 8% stillbirths) and 1451 reported no pregnancy loss. No significant differences in any cardiac or carotid parameters were evident in women who reported pregnancy loss compared to other groups (Table 1). Women who self-report pregnancy loss do not have significant differences in cardiac structure, cardiac function, or carotid structure in later life to explain their increased cardiovascular risk. This suggests any cardiovascular risks associated with pregnancy loss operate through other disease mechanisms. Alternatively, other characteristics of pregnancy loss, which we were not able to take account of, such as timing and number of pregnancy losses may be required to identify those at greatest cardiovascular risk. [ABSTRACT FROM AUTHOR]
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- 2019
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21. Physical activity and left ventricular trabeculation in the UK Biobank community-based cohort study.
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Woodbridge, Simon P., Nay Aung, Paiva, Jose M., Sanghvi, Mihir M., Zemrak, Filip, Fung, Kenneth, Petersen, Steffen E., and Aung, Nay
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PHYSICAL activity ,COHORT analysis ,CARDIAC magnetic resonance imaging - Abstract
Objective: Vigorous physical activity (PA) in highly trained athletes has been associated with heightened left ventricular (LV) trabeculation extent. It has therefore been hypothesised that LV trabeculation extent may participate in exercise-induced physiological cardiac remodelling. Our cross-sectional observational study aimed to ascertain whether there is a 'dose-response' relationship between PA and LV trabeculation extent and whether this could be identified at opposite PA extremes.Methods: In a cohort of 1030 individuals from the community-based UK Biobank study (male/female ratio: 0.84, mean age: 61 years), PA was measured via total metabolic equivalent of task (MET) min/week and 7-day average acceleration, and trabeculation extent via maximal non-compaction/compaction ratio (NC/C) in long-axis images of cardiovascular magnetic resonance studies. The relationship between PA and NC/C was assessed by multivariate regression (adjusting for potential confounders) as well as between demographic, anthropometric and LV phenotypic parameters and NC/C.Results: There was no significant linear relationship between PA and NC/C (full adjustment, total MET-min/week: ß=-0.0008, 95% CI -0.039 to -0.037, p=0.97; 7-day average acceleration: ß=-0.047, 95% CI -0.110 to -0.115, p=0.13, per IQR increment in PA), or between extreme PA quintiles (full adjustment, total MET-min/week: ß=-0.026, 95% CI -0.146 to -0.094, p=0.67; 7-day average acceleration: ß=-0.129, 95% CI -0.299 to -0.040, p=0.49), across all adjustment levels. A negative relationship was identified between left ventricular ejection fraction and NC/C, significantly modified by PA (ß difference=-0.006, p=0.03).Conclusions: In a community-based general population cohort, there was no relationship at, or between, extremes, between PA and NC/C, suggesting that at typical general population PA levels, trabeculation extent is not influenced by PA changes. [ABSTRACT FROM AUTHOR]- Published
- 2019
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22. Automated localization and quality control of the aorta in cine CMR can significantly accelerate processing of the UK Biobank population data.
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Biasiolli, Luca, Hann, Evan, Lukaschuk, Elena, Carapella, Valentina, Paiva, Jose M., Aung, Nay, Rayner, Jennifer J., Werys, Konrad, Fung, Kenneth, Puchta, Henrike, Sanghvi, Mihir M., Moon, Niall O., Thomson, Ross J., Thomas, Katharine E., Robson, Matthew D., Grau, Vicente, Petersen, Steffen E., Neubauer, Stefan, and Piechnik, Stefan K.
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CARDIAC magnetic resonance imaging ,FORCED vibration (Mechanics) ,RESONATORS ,CHEST (Anatomy) ,BLOOD circulation - Abstract
Introduction: Aortic distensibility can be calculated using semi-automated methods to segment the aortic lumen on cine CMR (Cardiovascular Magnetic Resonance) images. However, these methods require visual quality control and manual localization of the region of interest (ROI) of ascending (AA) and proximal descending (PDA) aorta, which limit the analysis in large-scale population-based studies. Using 5100 scans from UK Biobank, this study sought to develop and validate a fully automated method to 1) detect and locate the ROIs of AA and PDA, and 2) provide a quality control mechanism. Methods: The automated AA and PDA detection-localization algorithm followed these steps: 1) foreground segmentation; 2) detection of candidate ROIs by Circular Hough Transform (CHT); 3) spatial, histogram and shape feature extraction for candidate ROIs; 4) AA and PDA detection using Random Forest (RF); 5) quality control based on RF detection probability. To provide the ground truth, overall image quality (IQ = 0–3 from poor to good) and aortic locations were visually assessed by 13 observers. The automated algorithm was trained on 1200 scans and Dice Similarity Coefficient (DSC) was used to calculate the agreement between ground truth and automatically detected ROIs. Results: The automated algorithm was tested on 3900 scans. Detection accuracy was 99.4% for AA and 99.8% for PDA. Aorta localization showed excellent agreement with the ground truth, with DSC ≥ 0.9 in 94.8% of AA (DSC = 0.97 ± 0.04) and 99.5% of PDA cases (DSC = 0.98 ± 0.03). AA×PDA detection probabilities could discriminate scans with IQ ≥ 1 from those severely corrupted by artefacts (AUC = 90.6%). If scans with detection probability < 0.75 were excluded (350 scans), the algorithm was able to correctly detect and localize AA and PDA in all the remaining 3550 scans (100% accuracy). Conclusion: The proposed method for automated AA and PDA localization was extremely accurate and the automatically derived detection probabilities provided a robust mechanism to detect low quality scans for further human review. Applying the proposed localization and quality control techniques promises at least a ten-fold reduction in human involvement without sacrificing any accuracy. [ABSTRACT FROM AUTHOR]
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- 2019
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23. Association Between Ambient Air Pollution and Cardiac Morpho-Functional Phenotypes: Insights From the UK Biobank Population Imaging Study.
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Aung, Nay, Sanghvi, Mihir M., Zemrak, Filip, Lee, Aaron M., Cooper, Jackie A., Paiva, Jose M., Thomson, Ross J., Fung, Kenneth, Khanji, Mohammed Y., Lukaschuk, Elena, Carapella, Valentina, Kim, Young Jin, Munroe, Patricia B., Piechnik, Stefan K., Neubauer, Stefan, and Petersen, Steffen E.
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AIR pollution , *PHENOTYPES , *BIOBANKS , *HEART diseases ,CARDIOVASCULAR disease related mortality - Abstract
Background: Exposure to ambient air pollution is strongly associated with increased cardiovascular morbidity and mortality. Little is known about the influence of air pollutants on cardiac structure and function. We aim to investigate the relationship between chronic past exposure to traffic-related pollutants and the cardiac chamber volume, ejection fraction, and left ventricular remodeling patterns after accounting for potential confounders.Methods: Exposure to ambient air pollutants including particulate matter and nitrogen dioxide was estimated from the Land Use Regression models for the years between 2005 and 2010. Cardiac parameters were measured from cardiovascular magnetic resonance imaging studies of 3920 individuals free from pre-existing cardiovascular disease in the UK Biobank population study. The median (interquartile range) duration between the year of exposure estimate and the imaging visit was 5.2 (0.6) years. We fitted multivariable linear regression models to investigate the relationship between cardiac parameters and traffic-related pollutants after adjusting for various confounders.Results: The studied cohort was 62±7 years old, and 46% were men. In fully adjusted models, particulate matter with an aerodynamic diameter <2.5 μm concentration was significantly associated with larger left ventricular end-diastolic volume and end-systolic volume (effect size = 0.82%, 95% CI, 0.09-1.55%, P=0.027; and effect size = 1.28%, 95% CI, 0.15-2.43%, P=0.027, respectively, per interquartile range increment in particulate matter with an aerodynamic diameter <2.5 μm) and right ventricular end-diastolic volume (effect size = 0.85%, 95% CI, 0.12-1.58%, P=0.023, per interquartile range increment in particulate matter with an aerodynamic diameter <2.5 μm). Likewise, higher nitrogen dioxide concentration was associated with larger biventricular volume. Distance from the major roads was the only metric associated with lower left ventricular mass (effect size = -0.74%, 95% CI, -1.3% to -0.18%, P=0.01, per interquartile range increment). Neither left and right atrial phenotypes nor left ventricular geometric remodeling patterns were influenced by the ambient pollutants.Conclusions: In a large asymptomatic population with no prevalent cardiovascular disease, higher past exposure to particulate matter with an aerodynamic diameter <2.5 μm and nitrogen dioxide was associated with cardiac ventricular dilatation, a marker of adverse remodeling that often precedes heart failure development. [ABSTRACT FROM AUTHOR]- Published
- 2018
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24. Variation in lung function and alterations in cardiac structure and function—Analysis of the UK Biobank cardiovascular magnetic resonance imaging substudy.
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Thomson, Ross J., Aung, Nay, Sanghvi, Mihir M., Paiva, Jose Miguel, Lee, Aaron M., Zemrak, Filip, Fung, Kenneth, Pfeffer, Paul E., Mackay, Alexander J., McKeever, Tricia M., Lukaschuk, Elena, Carapella, Valentina, Kim, Young Jin, Bolton, Charlotte E., Piechnik, Stefan K., Neubauer, Stefan, and Petersen, Steffen E.
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LUNG disease diagnosis ,CARDIAC magnetic resonance imaging ,COMORBIDITY ,CARDIOPULMONARY system ,DISEASES ,PUBLIC health - Abstract
Background: Reduced lung function is common and associated with increased cardiovascular morbidity and mortality, even in asymptomatic individuals without diagnosed respiratory disease. Previous studies have identified relationships between lung function and cardiovascular structure in individuals with pulmonary disease, but the relationships in those free from diagnosed cardiorespiratory disease have not been fully explored. Methods: UK Biobank is a prospective cohort study of community participants in the United Kingdom. Individuals self-reported demographics and co-morbidities, and a subset underwent cardiovascular magnetic resonance (CMR) imaging and spirometry. CMR images were analysed to derive ventricular volumes and mass. The relationships between CMR-derived measures and spirometry and age were modelled with multivariable linear regression, taking account of the effects of possible confounders. Results: Data were available for 4,975 individuals, and after exclusion of those with pre-existing cardiorespiratory disease and unacceptable spirometry, 1,406 were included in the analyses. In fully-adjusted multivariable linear models lower FEV
1 and FVC were associated with smaller left ventricular end-diastolic (−5.21ml per standard deviation (SD) change in FEV1 , −5.69ml per SD change in FVC), end-systolic (−2.34ml, −2.56ml) and stroke volumes (−2.85ml, −3.11ml); right ventricular end-diastolic (−5.62ml, −5.84ml), end-systolic (−2.47ml, −2.46ml) and stroke volumes (−3.13ml, −3.36ml); and with lower left ventricular mass (−2.29g, −2.46g). Changes of comparable magnitude and direction were observed per decade increase in age. Conclusions: This study shows that reduced FEV1 and FVC are associated with smaller ventricular volumes and reduced ventricular mass. The changes seen per standard deviation change in FEV1 and FVC are comparable to one decade of ageing. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
25. Prospective association between handgrip strength and cardiac structure and function in UK adults.
- Author
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Beyer, Sebastian E., Sanghvi, Mihir M., Aung, Nay, Hosking, Alice, Cooper, Jackie A., Paiva, José Miguel, Lee, Aaron M., Fung, Kenneth, Lukaschuk, Elena, Carapella, Valentina, Mittleman, Murray A., Brage, Soren, Piechnik, Stefan K., Neubauer, Stefan, and Petersen, Steffen E.
- Subjects
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GRIP strength , *STROKE , *HEALTH outcome assessment , *CARDIAC magnetic resonance imaging ,CARDIOVASCULAR disease related mortality - Abstract
Background: Handgrip strength, a measure of muscular fitness, is associated with cardiovascular (CV) events and CV mortality but its association with cardiac structure and function is unknown. The goal of this study was to determine if handgrip strength is associated with changes in cardiac structure and function in UK adults. Methods and results: Left ventricular (LV) ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), mass (M), and mass-to-volume ratio (MVR) were measured in a sample of 4,654 participants of the UK Biobank Study 6.3 ± 1 years after baseline using cardiovascular magnetic resonance (CMR). Handgrip strength was measured at baseline and at the imaging follow-up examination. We determined the association between handgrip strength at baseline as well as its change over time and each of the cardiac outcome parameters. After adjustment, higher level of handgrip strength at baseline was associated with higher LVEDV (difference per SD increase in handgrip strength: 1.3ml, 95% CI 0.1–2.4; p = 0.034), higher LVSV (1.0ml, 0.3–1.8; p = 0.006), lower LVM (-1.0g, -1.8 –-0.3; p = 0.007), and lower LVMVR (-0.013g/ml, -0.018 –-0.007; p<0.001). The association between handgrip strength and LVEDV and LVSV was strongest among younger individuals, while the association with LVM and LVMVR was strongest among older individuals. Conclusions: Better handgrip strength was associated with cardiac structure and function in a pattern indicative of less cardiac hypertrophy and remodeling. These characteristics are known to be associated with a lower risk of cardiovascular events. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
26. The impact of menopausal hormone therapy (MHT) on cardiac structure and function: Insights from the UK Biobank imaging enhancement study.
- Author
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Sanghvi, Mihir M., Aung, Nay, Cooper, Jackie A., Paiva, José Miguel, Lee, Aaron M., Zemrak, Filip, Fung, Kenneth, Thomson, Ross J., Lukaschuk, Elena, Carapella, Valentina, Kim, Young Jin, Harvey, Nicholas C., Piechnik, Stefan K., Neubauer, Stefan, and Petersen, Steffen E.
- Subjects
- *
HORMONE therapy for menopause , *DIASTOLE (Cardiac cycle) , *CARDIAC magnetic resonance imaging , *VASCULAR medicine , *ENDOCRINOLOGY - Abstract
Background: The effect of menopausal hormone therapy (MHT)–previously known as hormone replacement therapy–on cardiovascular health remains unclear and controversial. This cross-sectional study examined the impact of MHT on left ventricular (LV) and left atrial (LA) structure and function, alterations in which are markers of subclinical cardiovascular disease, in a population-based cohort. Methods: Post-menopausal women who had never used MHT and those who had used MHT ≥3 years participating in the UK Biobank who had undergone cardiovascular magnetic resonance (CMR) imaging and free of known cardiovascular disease were included. Multivariable linear regression was performed to examine the relationship between cardiac parameters and MHT use ≥3 years. To explore whether MHT use on each of the cardiac outcomes differed by age, multivariable regression models were constructed with a cross-product of age and MHT fitted as an interaction term. Results: Of 1604 post-menopausal women, 513 (32%) had used MHT ≥3 years. In the MHT cohort, median age at menopause was 50 (IQR: 45–52) and median duration of MHT was 8 years. In the non-MHT cohort, median age at menopause was 51 (IQR: 48–53). MHT use was associated with significantly lower LV end-diastolic volume (122.8 ml vs 119.8 ml, effect size = -2.4%, 95% CI: -4.2% to -0.5%; p = 0.013) and LA maximal volume (60.2 ml vs 57.5 ml, effect size = -4.5%, 95% CI: -7.8% to -1.0%; p = 0.012). There was no significant difference in LV mass. MHT use significantly modified the effect between age and CMR parameters; MHT users had greater decrements in LV end-diastolic volume, LV end-systolic volume and LA maximal volume with advancing age. Conclusions: MHT use was not associated with adverse, subclinical changes in cardiac structure and function. Indeed, significantly smaller LV and LA chamber volumes were observed which have been linked to favourable cardiovascular outcomes. These findings represent a novel approach to examining MHT’s effect on the cardiovascular system. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
27. Fully-automated left ventricular mass and volume MRI analysis in the UK Biobank population cohort: evaluation of initial results.
- Author
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Suinesiaputra, Avan, Sanghvi, Mihir M., Aung, Nay, Paiva, Jose Miguel, Zemrak, Filip, Fung, Kenneth, Lukaschuk, Elena, Lee, Aaron M., Carapella, Valentina, Kim, Young Jin, Francis, Jane, Piechnik, Stefan K., Neubauer, Stefan, Greiser, Andreas, Jolly, Marie-Pierre, Hayes, Carmel, Young, Alistair A., and Petersen, Steffen E.
- Abstract
UK Biobank, a large cohort study, plans to acquire 100,000 cardiac MRI studies by 2020. Although fully-automated left ventricular (LV) analysis was performed in the original acquisition, this was not designed for unsupervised incorporation into epidemiological studies. We sought to evaluate automated LV mass and volume (Siemens syngo InlineVF versions D13A and E11C), against manual analysis in a substantial sub-cohort of UK Biobank participants. Eight readers from two centers, trained to give consistent results, manually analyzed 4874 UK Biobank cases for LV end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF) and LV mass (LVM). Agreement between manual and InlineVF automated analyses were evaluated using Bland-Altman analysis and the intra-class correlation coefficient (ICC). Tenfold cross-validation was used to establish a linear regression calibration between manual and InlineVF results. InlineVF D13A returned results in 4423 cases, whereas InlineVF E11C returned results in 4775 cases and also reported LVM. Rapid visual assessment of the E11C results found 178 cases (3.7%) with grossly misplaced contours or landmarks. In the remaining 4597 cases, LV function showed good agreement: ESV -6.4 ± 9.0 ml, 0.853 (mean ± SD of the differences, ICC) EDV -3.0 ± 11.6 ml, 0.937; SV 3.4 ± 9.8 ml, 0.855; and EF 3.5 ± 5.1%, 0.586. Although LV mass was consistently overestimated (29.9 ± 17.0 g, 0.534) due to larger epicardial contours on all slices, linear regression could be used to correct the bias and improve accuracy. Automated InlineVF results can be used for case-control studies in UK Biobank, provided visual quality control and linear bias correction are performed. Improvements between InlineVF D13A and InlineVF E11C show the field is rapidly advancing, with further improvements expected in the near future. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
28. The impact of cardiovascular risk factors on cardiac structure and function: Insights from the UK Biobank imaging enhancement study.
- Author
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Petersen, Steffen E., Sanghvi, Mihir M., Aung, Nay, Cooper, Jackie A., Paiva, José Miguel, Zemrak, Filip, Fung, Kenneth, Lukaschuk, Elena, Lee, Aaron M., Carapella, Valentina, Kim, Young Jin, Piechnik, Stefan K., and Neubauer, Stefan
- Subjects
- *
CARDIOVASCULAR disease diagnosis , *HEART function tests , *CARDIAC imaging , *CARDIOVASCULAR diseases risk factors , *VENTRICULAR ejection fraction - Abstract
Aims: The UK Biobank is a large-scale population-based study utilising cardiovascular magnetic resonance (CMR) to generate measurements of atrial and ventricular structure and function. This study aimed to quantify the association between modifiable cardiovascular risk factors and cardiac morphology and function in individuals without known cardiovascular disease. Methods: Age, sex, ethnicity (non-modifiable) and systolic blood pressure, diastolic blood pressure, smoking status, exercise, body mass index (BMI), high cholesterol, diabetes, alcohol intake (modifiable) were considered important cardiovascular risk factors. Multivariable regression models were built to ascertain the association of risk factors on left ventricular (LV), right ventricular (RV), left atrial (LA) and right atrial (RA) CMR parameters. Results: 4,651 participants were included in the analysis. All modifiable risk factors had significant effects on differing atrial and ventricular parameters. BMI was the modifiable risk factor most consistently associated with subclinical changes to CMR parameters, particularly in relation to higher LV mass (+8.3% per SD [4.3 kg/m2], 95% CI: 7.6 to 8.9%), LV (EDV: +4.8% per SD, 95% CI: 4.2 to 5.4%); ESV: +4.4% per SD, 95% CI: 3.5 to 5.3%), RV (EDV: +5.3% per SD, 95% CI: 4.7 to 5.9%; ESV: +5.4% per SD, 95% CI: 4.5 to 6.4%) and LA maximal (+8.6% per SD, 95% CI: 7.4 to 9.7%) volumes. Increases in SBP were associated with higher LV mass (+6.8% per SD, 95% CI: 5.9 to 7.7%), LV (EDV: +4.5% per SD, 95% CI: 3.6 to 5.4%; ESV: +2.0% per SD, 95% CI: 0.8 to 3.3%) volumes. The presence of diabetes or high cholesterol resulted in smaller volumes and lower ejection fractions. Conclusions: Modifiable risk factors are associated with subclinical alterations in structure and function in all four cardiac chambers. BMI and systolic blood pressure are the most important modifiable risk factors affecting CMR parameters known to be linked to adverse outcomes. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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- View/download PDF
29. Reference ranges for cardiac structure and function using cardiovascular magnetic resonance (CMR) in Caucasians from the UK Biobank population cohort.
- Author
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Petersen, Steffen E., Nay Aung, Sanghvi, Mihir M., Zemrak, Filip, Fung, Kenneth, Miguel Paiva, Jose, Francis, Jane M., Khanji, Mohammed Y., Lukaschuk, Elena, Lee, Aaron M., Carapella, Valentina, Young Jin Kim, Leeson, Paul, Piechnik, Stefan K., and Neubauer, Stefan
- Subjects
HEART atrium ,HEART ventricles ,AGE distribution ,STATISTICAL correlation ,LEFT heart ventricle ,HEART physiology ,RIGHT heart ventricle ,MAGNETIC resonance imaging ,REFERENCE values ,RESEARCH funding ,SEX distribution ,T-test (Statistics) ,WHITE people ,DATA analysis software ,STROKE volume (Cardiac output) ,INTRACLASS correlation ,PHYSIOLOGY ,ANATOMY - Abstract
Background: Cardiovascular magnetic resonance (CMR) is the gold standard method for the assessment of cardiac structure and function. Reference ranges permit differentiation between normal and pathological states. To date, this study is the largest to provide CMR specific reference ranges for left ventricular, right ventricular, left atrial and right atrial structure and function derived from truly healthy Caucasian adults aged 45-74. Methods: Five thousand sixty-five UK Biobank participants underwent CMR using steady-state free precession imaging at 1.5 Tesla. Manual analysis was performed for all four cardiac chambers. Participants with non-Caucasian ethnicity, known cardiovascular disease and other conditions known to affect cardiac chamber size and function were excluded. Remaining participants formed the healthy reference cohort; reference ranges were calculated and were stratified by gender and age (45-54, 55-64, 65-74). Results: After applying exclusion criteria, 804 (16.²%) participants were available for analysis. Left ventricular (LV) volumes were larger in males compared to females for absolute and indexed values. With advancing age, LV volumes were mostly smaller in both sexes. LV ejection fraction was significantly greater in females compared to males (mean ± standard deviation [SD] of 61 ± 5% vs 58 ± 5%) and remained static with age for both genders. In older age groups, LV mass was lower in men, but remained virtually unchanged in women. LV mass was significantly higher in males compared to females (mean ± SD of 53 ± 9 g/m² vs 4² ± 7 g/m²). Right ventricular (RV) volumes were significantly larger in males compared to females for absolute and indexed values and were smaller with advancing age. RV ejection fraction was higher with increasing age in females only. Left atrial (LA) maximal volume and stroke volume were significantly larger in males compared to females for absolute values but not for indexed values. LA ejection fraction was similar for both sexes. Right atrial (RA) maximal volume was significantly larger in males for both absolute and indexed values, while RA ejection fraction was significantly higher in females. Conclusions: We describe age- and sex-specific reference ranges for the left ventricle, right ventricle and atria in the largest validated normal Caucasian population. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
30. Variably severe systemic allergic reactions after consuming foods with unlabelled lupin flour: a case series.
- Author
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Bansal, Amolak A. S., Sanghvi, Mihir M., Bansal, Rhea A., and Hayman, Grant R.
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ANAPHYLAXIS , *PEANUT allergy , *ALLERGENS , *URTICARIA , *SKIN tests - Abstract
Introduction Lupin allergy remains a significant cause of food-induced allergic reactivity and anaphylaxis. Previous work suggests a strong association with legume allergy and peanut allergy in particular. Both doctors and the public have little awareness of lupin as an allergen. Case presentation Case 1 was a 41-year-old Caucasian woman without previous atopy who developed facial swelling, widespread urticaria with asthma and hypotension within minutes of eating a quiche. Her lupin allergy was confirmed by both blood and skin tests. Her lupin sensitivity was so severe that even the miniscule amount of lupin allergen in the skin testing reagent produced a mild reaction. Case 2 was a 42-year-old mildly atopic Caucasian woman with three episodes of worsening urticaria and asthma symptoms over 6 years occurring after the consumption of foods containing lupin flour. Blood and skin tests were positive for lupin allergy. Case 3 was a 38-year-old Caucasian woman with known oral allergy syndrome who had two reactions associated with urticaria and vomiting after consuming foods containing lupin flour. Skin testing confirmed significant responses to a lupin flour extract and to one of the foods inducing her reaction. Case 4 was a 54-year-old mildly atopic Caucasian woman with a 7 year history of three to four episodes each year of unpredictable oral tingling followed by urticaria after consuming a variety of foods. The most recent episode had been associated with vomiting. She had developed oral tingling with lentil and chickpeas over the previous year. Skin and blood tests confirmed lupin allergy with associated sensitivity to several legumes. Conclusions Lupin allergy can occur for the first time in adults without previous atopy or legume sensitivity. Although asymptomatic sensitisation is frequent, clinical reactivity can vary in severity from severe anaphylaxis to urticaria and vomiting. Lupin allergy may be confirmed by skin and specific immunoglobulin E estimation. Even skin testing can cause symptoms in some highly sensitive individuals. The diagnosis of lupin allergy in adults may be difficult because it is frequently included as an undeclared ingredient. Better food labelling and medical awareness of lupin as a cause of serious allergic reactions is suggested. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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31. Delayed diagnosis of anaphylaxis secondary to ondansetron: A case report.
- Author
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Goyal, Preeti, Paramesh, Kaggere, Puranik, Sarang, Proctor, Mark, and Sanghvi, Mihir
- Published
- 2016
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32. Centrifugation enhances integrin-mediated transduction of dendritic cells by conventional and RGD-modified adenoviral vectors
- Author
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Harui, Airi, Roth, Michael D., Sanghvi, Mihir, Vira, Darshni, Mizuguchi, Hiroyuki, and Basak, Saroj K.
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DENDRITIC cells , *LYMPHOID tissue , *BACTERIOPHAGES , *GREEN fluorescent protein - Abstract
Abstract: The level of antigen loading can impact on the capacity for dendritic cells (DC) to activate T cell responses. Several different approaches to adenoviral (Ad)-based transduction were therefore assessed for their effect on both transgene expression and T cell activation. While a conventional E1(−)/E3Δ Ad vector (Ad/GFP) produced a concentration-dependent expression of GFP, a modified vector expressing Arginine–Glycine–Aspartic Acid (RGD) sequence on its fiber knob (Ad-RGD/GFP) enhanced transgene expression by 9–20-fold at each MOI. The addition of centrifugal force (2000×g) during DC transduction with Ad/GFP also increased expression up to 20-fold. However, combining centrifugation with the Ad-RGD/GFP vector produced no effect on transduction rate and only a 1.5- to 2-fold increase in GFP expression, suggesting overlapping mechanisms of action. Consistent with this, exogenous RGD peptide blocked transduction regardless of the vector used, or the addition of centrifugal force, and transduction was primarily limited to DC expressing the CD51 integrin receptor. Ad vectors expressing ovalbumin (OVA) were used to assess transduced DC for their capacity to activate OVA-specific T cells. We observed a significant relationship between transgene expression and the capacity for T cell activation regardless of whether transgene expression was increased by using a higher MOI, an RGD-modified vector, or by employing centrifugal force. Furthermore, combining these approaches produced synergistic effects on T cell activation. We conclude that RGD-modified vectors and centrifugation both enhance DC transduction by increasing entry via integrin receptors and that the capacity for T cell activation can be optimized by combining approaches to achieve the highest possible level of transgene expression. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
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