The Experts below are selected from a list of 228 Experts worldwide ranked by ideXlab platform
Muzahir H. Tayebjee - One of the best experts on this subject based on the ideXlab platform.
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P wave indices, heart rate variability and anthropometry in a healthy South Asian population.
PloS one, 2019Co-Authors: James O’neill, Sven Plein, Katrina Bounford, Alice Anstey, Jesvita D’silva, Lisa Clark, Muzahir H. TayebjeeAbstract:Background South Asians have a low prevalence of Atrial fibrillation (AF) in comparison with White Europeans despite a higher burden of hypertension, diabetes mellitus and coronary artery disease. The reason for this disparity is unclear but may relate to electrophysiological or structural differences within the atria or variations in autonomic function. We aimed to assess these areas using a range of non-invasive cardiac investigations. Methods A prospective cohort study was performed on 200 South Asian and 200 Caucasian healthy volunteers aged 18–40 years. All subjects underwent electrocardiography (ECG), echocardiography and anthropometric measurements. Eighty subjects in each cohort underwent 24 hour ambulatory ECG and fifty subjects in each cohort underwent exercise testing. Results Compared with White Europeans, South Asians were of a smaller height with lower lean body mass and smaller left Atrial size. They had reduced P wave dispersion and P wave terminal force in lead V1. South Asians had a lower burden of supraventricular ectopy. They had a higher mean heart rate and South Asian males had lower heart rate variability, suggestive of sympathetic predominance. Exercise capacity was lower in South Asians. Conclusions South Asians have differences in left Atrial size, P wave indices, burden of supraventricular ectopy, heart rate, heart rate variability and anthropometric measurements. These differences may relate to variations in Atrial Morphology, Atrial electrophysiology and autonomic function and might help to explain why South Asians are less susceptible to developing AF.
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Left Atrial size and function in a South Asian population and their potential influence on the risk of Atrial fibrillation.
Clinical cardiology, 2018Co-Authors: James O’neill, Peter P Swoboda, Sven Plein, Muzahir H. TayebjeeAbstract:Background: South Asians have a low prevalence of Atrial fibrillation (AF) compared with Caucasians despite having a higher prevalence of conventional risk factors for the arrhythmia. The reason for this disparity is uncertain but may be due to ethnic differences in Atrial Morphology. This study examines the association between ethnicity and left Atrial (LA) size and function in South Asian and Caucasian subjects using the reference technique of cardiovascular magnetic resonance imaging (MRI). Hypothesis: South Asians have smaller LA size and therefore increased LA function. Methods: Retrospective case‐control study of 60 South Asian and 60 Caucasian patients who had undergone a clinically indicated MRI between April 2010 and October 2017 and had been found to have a structurally normal heart. LA and left ventricular (LV) volume and function were assessed and compared between the ethnicities. Results: In comparison with Caucasians, South Asians had significantly lower minimum (27.7 ± 11.1 mL vs 34.9 ± 12.3 mL, P = 0.002) and maximum LA volumes (64.7 ± 21.1 mL vs 80.9 ± 22.5 mL, P
Thomas L Spray - One of the best experts on this subject based on the ideXlab platform.
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the hypoplastic left heart syndrome with intact Atrial septum Atrial Morphology pulmonary vascular histopathology and outcome
Journal of the American College of Cardiology, 1999Co-Authors: Jack Rychik, Jonathan J Rome, Margaret H Collins, William M Decampli, Thomas L SprayAbstract:Abstract OBJECTIVES The purpose of this study was to investigate the outcome in infants with hypoplastic left heart syndrome and intact Atrial septum and to evaluate the relationship of Atrial Morphology, left Atrial decompression pathway and lung histopathology to outcome. BACKGROUND In the hypoplastic left heart syndrome, severe restriction at the Atrial level results in marked systemic hypoxemia after birth. Infants with intact Atrial septum may be at high risk for mortality after Norwood operation. METHODS Of 316 infants with hypoplastic left heart syndrome seen at our center over a 6.5-year period, 18 (5.7%) had intact Atrial septum. Medical records and echocardiograms were reviewed. RESULTS On echocardiography, three types of intact Atrial septal Morphology were identified: 1) large left atrium, thick prominent septum 2° with thin septum 1° adherent (type A, n = 12); 2) small left atrium with thick, muscular Atrial septum (type B, n = 4), and 3) giant left atrium, thin Atrial septum with severe mitral regurgitation (type C, n = 2). Seven infants had left Atrial decompression pathways that were severely obstructed (3/12 type A, 4/4 type B). Norwood operation was performed in 17 infants; one underwent emergency balloon Atrial septostomy and died. Of six early survivors, all with type A Atrial Morphology and unobstructed decompression pathway; three died after subsequent cavopulmonary surgery. Lung histopathology revealed severely dilated lymphatics and “arterialization” of the pulmonary veins in those with the severest degree of obstruction to left Atrial egress (type B Atrial Morphology). CONCLUSIONS Despite aggressive intervention, outcome for infants born with hypoplastic left heart syndrome and intact Atrial septum is poor. Maldevelopment of the pulmonary vasculature contributes to the high mortality seen. Atrial Morphology can be used as a marker for the severity of pulmonary vascular disease.
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The hypoplastic left heart syndrome with intact Atrial septum: Atrial Morphology, pulmonary vascular histopathology and outcome.
Journal of the American College of Cardiology, 1999Co-Authors: Jack Rychik, Jonathan J Rome, Margaret H Collins, William M Decampli, Thomas L SprayAbstract:The purpose of this study was to investigate the outcome in infants with hypoplastic left heart syndrome and intact Atrial septum and to evaluate the relationship of Atrial Morphology, left Atrial decompression pathway and lung histopathology to outcome. In the hypoplastic left heart syndrome, severe restriction at the Atrial level results in marked systemic hypoxemia after birth. Infants with intact Atrial septum may be at high risk for mortality after Norwood operation. Of 316 infants with hypoplastic left heart syndrome seen at our center over a 6.5-year period, 18 (5.7%) had intact Atrial septum. Medical records and echocardiograms were reviewed. On echocardiography, three types of intact Atrial septal Morphology were identified: 1) large left atrium, thick prominent septum secondary with thin septum primary adherent (type A, n = 12); 2) small left atrium with thick, muscular Atrial septum (type B, n = 4), and 3) giant left atrium, thin Atrial septum with severe mitral regurgitation (type C, n = 2). Seven infants had left Atrial decompression pathways that were severely obstructed (3/12 type A, 4/4 type B). Norwood operation was performed in 17 infants; one underwent emergency balloon Atrial septostomy and died. Of six early survivors, all with type A Atrial Morphology and unobstructed decompression pathway, three died after subsequent cavopulmonary surgery. Lung histopathology revealed severely dilated lymphatics and "arterialization" of the pulmonary veins in those with the severest degree of obstruction to left Atrial egress (type B Atrial Morphology). Despite aggressive intervention, outcome for infants born with hypoplastic left heart syndrome and intact Atrial septum is poor. Maldevelopment of the pulmonary vasculature contributes to the high mortality seen. Atrial Morphology can be used as a marker for the severity of pulmonary vascular disease.
James O’neill - One of the best experts on this subject based on the ideXlab platform.
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P wave indices, heart rate variability and anthropometry in a healthy South Asian population.
PloS one, 2019Co-Authors: James O’neill, Sven Plein, Katrina Bounford, Alice Anstey, Jesvita D’silva, Lisa Clark, Muzahir H. TayebjeeAbstract:Background South Asians have a low prevalence of Atrial fibrillation (AF) in comparison with White Europeans despite a higher burden of hypertension, diabetes mellitus and coronary artery disease. The reason for this disparity is unclear but may relate to electrophysiological or structural differences within the atria or variations in autonomic function. We aimed to assess these areas using a range of non-invasive cardiac investigations. Methods A prospective cohort study was performed on 200 South Asian and 200 Caucasian healthy volunteers aged 18–40 years. All subjects underwent electrocardiography (ECG), echocardiography and anthropometric measurements. Eighty subjects in each cohort underwent 24 hour ambulatory ECG and fifty subjects in each cohort underwent exercise testing. Results Compared with White Europeans, South Asians were of a smaller height with lower lean body mass and smaller left Atrial size. They had reduced P wave dispersion and P wave terminal force in lead V1. South Asians had a lower burden of supraventricular ectopy. They had a higher mean heart rate and South Asian males had lower heart rate variability, suggestive of sympathetic predominance. Exercise capacity was lower in South Asians. Conclusions South Asians have differences in left Atrial size, P wave indices, burden of supraventricular ectopy, heart rate, heart rate variability and anthropometric measurements. These differences may relate to variations in Atrial Morphology, Atrial electrophysiology and autonomic function and might help to explain why South Asians are less susceptible to developing AF.
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Left Atrial size and function in a South Asian population and their potential influence on the risk of Atrial fibrillation.
Clinical cardiology, 2018Co-Authors: James O’neill, Peter P Swoboda, Sven Plein, Muzahir H. TayebjeeAbstract:Background: South Asians have a low prevalence of Atrial fibrillation (AF) compared with Caucasians despite having a higher prevalence of conventional risk factors for the arrhythmia. The reason for this disparity is uncertain but may be due to ethnic differences in Atrial Morphology. This study examines the association between ethnicity and left Atrial (LA) size and function in South Asian and Caucasian subjects using the reference technique of cardiovascular magnetic resonance imaging (MRI). Hypothesis: South Asians have smaller LA size and therefore increased LA function. Methods: Retrospective case‐control study of 60 South Asian and 60 Caucasian patients who had undergone a clinically indicated MRI between April 2010 and October 2017 and had been found to have a structurally normal heart. LA and left ventricular (LV) volume and function were assessed and compared between the ethnicities. Results: In comparison with Caucasians, South Asians had significantly lower minimum (27.7 ± 11.1 mL vs 34.9 ± 12.3 mL, P = 0.002) and maximum LA volumes (64.7 ± 21.1 mL vs 80.9 ± 22.5 mL, P
Jack Rychik - One of the best experts on this subject based on the ideXlab platform.
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the hypoplastic left heart syndrome with intact Atrial septum Atrial Morphology pulmonary vascular histopathology and outcome
Journal of the American College of Cardiology, 1999Co-Authors: Jack Rychik, Jonathan J Rome, Margaret H Collins, William M Decampli, Thomas L SprayAbstract:Abstract OBJECTIVES The purpose of this study was to investigate the outcome in infants with hypoplastic left heart syndrome and intact Atrial septum and to evaluate the relationship of Atrial Morphology, left Atrial decompression pathway and lung histopathology to outcome. BACKGROUND In the hypoplastic left heart syndrome, severe restriction at the Atrial level results in marked systemic hypoxemia after birth. Infants with intact Atrial septum may be at high risk for mortality after Norwood operation. METHODS Of 316 infants with hypoplastic left heart syndrome seen at our center over a 6.5-year period, 18 (5.7%) had intact Atrial septum. Medical records and echocardiograms were reviewed. RESULTS On echocardiography, three types of intact Atrial septal Morphology were identified: 1) large left atrium, thick prominent septum 2° with thin septum 1° adherent (type A, n = 12); 2) small left atrium with thick, muscular Atrial septum (type B, n = 4), and 3) giant left atrium, thin Atrial septum with severe mitral regurgitation (type C, n = 2). Seven infants had left Atrial decompression pathways that were severely obstructed (3/12 type A, 4/4 type B). Norwood operation was performed in 17 infants; one underwent emergency balloon Atrial septostomy and died. Of six early survivors, all with type A Atrial Morphology and unobstructed decompression pathway; three died after subsequent cavopulmonary surgery. Lung histopathology revealed severely dilated lymphatics and “arterialization” of the pulmonary veins in those with the severest degree of obstruction to left Atrial egress (type B Atrial Morphology). CONCLUSIONS Despite aggressive intervention, outcome for infants born with hypoplastic left heart syndrome and intact Atrial septum is poor. Maldevelopment of the pulmonary vasculature contributes to the high mortality seen. Atrial Morphology can be used as a marker for the severity of pulmonary vascular disease.
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The hypoplastic left heart syndrome with intact Atrial septum: Atrial Morphology, pulmonary vascular histopathology and outcome.
Journal of the American College of Cardiology, 1999Co-Authors: Jack Rychik, Jonathan J Rome, Margaret H Collins, William M Decampli, Thomas L SprayAbstract:The purpose of this study was to investigate the outcome in infants with hypoplastic left heart syndrome and intact Atrial septum and to evaluate the relationship of Atrial Morphology, left Atrial decompression pathway and lung histopathology to outcome. In the hypoplastic left heart syndrome, severe restriction at the Atrial level results in marked systemic hypoxemia after birth. Infants with intact Atrial septum may be at high risk for mortality after Norwood operation. Of 316 infants with hypoplastic left heart syndrome seen at our center over a 6.5-year period, 18 (5.7%) had intact Atrial septum. Medical records and echocardiograms were reviewed. On echocardiography, three types of intact Atrial septal Morphology were identified: 1) large left atrium, thick prominent septum secondary with thin septum primary adherent (type A, n = 12); 2) small left atrium with thick, muscular Atrial septum (type B, n = 4), and 3) giant left atrium, thin Atrial septum with severe mitral regurgitation (type C, n = 2). Seven infants had left Atrial decompression pathways that were severely obstructed (3/12 type A, 4/4 type B). Norwood operation was performed in 17 infants; one underwent emergency balloon Atrial septostomy and died. Of six early survivors, all with type A Atrial Morphology and unobstructed decompression pathway, three died after subsequent cavopulmonary surgery. Lung histopathology revealed severely dilated lymphatics and "arterialization" of the pulmonary veins in those with the severest degree of obstruction to left Atrial egress (type B Atrial Morphology). Despite aggressive intervention, outcome for infants born with hypoplastic left heart syndrome and intact Atrial septum is poor. Maldevelopment of the pulmonary vasculature contributes to the high mortality seen. Atrial Morphology can be used as a marker for the severity of pulmonary vascular disease.
Sven Plein - One of the best experts on this subject based on the ideXlab platform.
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P wave indices, heart rate variability and anthropometry in a healthy South Asian population.
PloS one, 2019Co-Authors: James O’neill, Sven Plein, Katrina Bounford, Alice Anstey, Jesvita D’silva, Lisa Clark, Muzahir H. TayebjeeAbstract:Background South Asians have a low prevalence of Atrial fibrillation (AF) in comparison with White Europeans despite a higher burden of hypertension, diabetes mellitus and coronary artery disease. The reason for this disparity is unclear but may relate to electrophysiological or structural differences within the atria or variations in autonomic function. We aimed to assess these areas using a range of non-invasive cardiac investigations. Methods A prospective cohort study was performed on 200 South Asian and 200 Caucasian healthy volunteers aged 18–40 years. All subjects underwent electrocardiography (ECG), echocardiography and anthropometric measurements. Eighty subjects in each cohort underwent 24 hour ambulatory ECG and fifty subjects in each cohort underwent exercise testing. Results Compared with White Europeans, South Asians were of a smaller height with lower lean body mass and smaller left Atrial size. They had reduced P wave dispersion and P wave terminal force in lead V1. South Asians had a lower burden of supraventricular ectopy. They had a higher mean heart rate and South Asian males had lower heart rate variability, suggestive of sympathetic predominance. Exercise capacity was lower in South Asians. Conclusions South Asians have differences in left Atrial size, P wave indices, burden of supraventricular ectopy, heart rate, heart rate variability and anthropometric measurements. These differences may relate to variations in Atrial Morphology, Atrial electrophysiology and autonomic function and might help to explain why South Asians are less susceptible to developing AF.
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Left Atrial size and function in a South Asian population and their potential influence on the risk of Atrial fibrillation.
Clinical cardiology, 2018Co-Authors: James O’neill, Peter P Swoboda, Sven Plein, Muzahir H. TayebjeeAbstract:Background: South Asians have a low prevalence of Atrial fibrillation (AF) compared with Caucasians despite having a higher prevalence of conventional risk factors for the arrhythmia. The reason for this disparity is uncertain but may be due to ethnic differences in Atrial Morphology. This study examines the association between ethnicity and left Atrial (LA) size and function in South Asian and Caucasian subjects using the reference technique of cardiovascular magnetic resonance imaging (MRI). Hypothesis: South Asians have smaller LA size and therefore increased LA function. Methods: Retrospective case‐control study of 60 South Asian and 60 Caucasian patients who had undergone a clinically indicated MRI between April 2010 and October 2017 and had been found to have a structurally normal heart. LA and left ventricular (LV) volume and function were assessed and compared between the ethnicities. Results: In comparison with Caucasians, South Asians had significantly lower minimum (27.7 ± 11.1 mL vs 34.9 ± 12.3 mL, P = 0.002) and maximum LA volumes (64.7 ± 21.1 mL vs 80.9 ± 22.5 mL, P