Syncope is a concerning symptom that affects a large proportion of patients.It can be related to a heterogeneous group of pathologies ranging from trivial causes to diseases with a high risk of sudden death.However,be...Syncope is a concerning symptom that affects a large proportion of patients.It can be related to a heterogeneous group of pathologies ranging from trivial causes to diseases with a high risk of sudden death.However,benign causes are the most frequent,and identifying high-risk patients with potentially severe etiologies is crucial to establish an accurate diagnosis,initiate effective therapy,and alter the prognosis.The term cardiac syncope refers to those episodes where the cause of the cerebral hypoperfusion is directly related to a cardiac disorder,while arrhythmic syncope is cardiac syncope specifically due to rhythm disorders.Indeed,arrhythmias are the most common cause of cardiac syncope.Both bradyarrhythmia and tachyarrhythmia can cause a sudden decrease in cardiac output and produce syncope.In this review,we summarized the main guidelines in the management of patients with syncope of presumed arrhythmic origin.Therefore,we presented a thorough approach to syncope work-up through different tests depending on the clinical characteristics of the patients,risk stratification,and the management of syncope in different scenarios such as structural heart disease and channelopathies.展开更多
Background:To compare objective electrophysiological contrast sensitivity function(CSF)in patients implanted with either multifocal intraocular lenses(MIOLs)or monofocal intraocular lenses(IOLs)by pattern reversal vis...Background:To compare objective electrophysiological contrast sensitivity function(CSF)in patients implanted with either multifocal intraocular lenses(MIOLs)or monofocal intraocular lenses(IOLs)by pattern reversal visual evoked potentials(prVEP)measurements.Methods:Fourty-five cataract patients were randomly allocated to receive bilaterally:apodized diffractive-refractive Alcon Acrysof MIOL(A),full diffractive AMO Tecnis MIOL(B)or monofocal Alcon Acrysof IOL(C).Primary outcomes:1-year differences in objective binocular CSF measured by prVEP with sinusoid grating stimuli of 6 decreasing contrast levels at 6 spatial frequencies.Secondary outcomes:psychophysical CSF measured with VCTS-6500,photopic uncorrected distance(UDVA),and mesopic and photopic uncorrected near and intermediate visual acuities(UNVA and UIVA respectively).Results:Electrophysiological CSF curve had an inverted U-shaped morphology in all groups,with a biphasic pattern in Group B.Group A showed a lower CSF than group B at 4 and 8 cpd,and a lower value than group C at 8 cpd.Psychophysical CSF in group A exhibited a lower value at 12 cpd than group B.Mean photopic and mesopic UNVA and UIVA were worse in monofocal group compared to the multifocal groups.Mesopic UNVA and UIVA were better in group B.Conclusions:Electrophysiological CSF behaves differently depending on the types of multifocal or monofocal IOLs.This may be related to the visual acuity under certain conditions or to IOL characteristics.This objective method might be a potential new tool to investigate on MIOL differences and on subjective device-related quality of vision.展开更多
Objective Chronic atrial fibrillation （AF） results in dedifferentiation of atrial cardiomyocytes that plays an important role in the perpetuation of AF. In this study, we aimed to investigate the changes oftitin and...Objective Chronic atrial fibrillation （AF） results in dedifferentiation of atrial cardiomyocytes that plays an important role in the perpetuation of AF. In this study, we aimed to investigate the changes oftitin and a-smooth muscle actin （α-SMA） after long time of AF reversal. Methods Twenty-four goats were randomized into four groups： （1） sinus rhythm （SR）, （2） 3 months AF （3-too AF）, （3） 3 months SR after 3 months AF （3-mo post AF）, （4） 6 months SR after 3-mo AF （6-mo post AF）, with 6 in each group. By pacing on the anterior bottom of left atria appendage （LAA）, we established a goat model of chronic AF. Atria effective refractory period （AERP） was measured with electrophysiological methods. Ultra-structure was studied with echocardiography, light and electron microscopy. Titin and α-SMA protein expressions were determined by Western blot. Results The animals underwent high rate pacing on LAA for a mean of 42.23± 21.70 days before presenting AF. Electrophysiological analysis revealed that AERP completely resumed in 3-mo post AF goats. Echocardiography displayed that the size of left atrium resumed almost in 6-too post AF goats （P〈 0.01）. Pathological and electron microscopic examination revealed the disorder of myofibrils, augmentation of intercellular space, myolysis, accumulation of glycogen, and numerous bigger mitochondria among atrial cardiomyocytes in 3-mo AF goats. They recovered mostly in 6-mo post AF goats. Western blot showed that the band density oftitin significantly reduced in 3-mo AF goats compared to SR ones [1826 ± 319 vs 5012±854, P 〈 0.01]. In 3- and 6-mo post AF goats, titin increased gradually and it reversed completely in 6-mo post AF goats （3841 ± 601 and 4523 ±833 respectively, P 〈 0.01）. Conversely, the band density ofa-SMAwas significantly higher in 3-mo AF goats （5324 ± 948） than in SR ones （1619 ±271, P 〈 0.01）. In 3- and 6-mo post-AF goats, α-SMA decreased gradually, and it recovered mostly in 6- mo p展开更多
文摘Syncope is a concerning symptom that affects a large proportion of patients.It can be related to a heterogeneous group of pathologies ranging from trivial causes to diseases with a high risk of sudden death.However,benign causes are the most frequent,and identifying high-risk patients with potentially severe etiologies is crucial to establish an accurate diagnosis,initiate effective therapy,and alter the prognosis.The term cardiac syncope refers to those episodes where the cause of the cerebral hypoperfusion is directly related to a cardiac disorder,while arrhythmic syncope is cardiac syncope specifically due to rhythm disorders.Indeed,arrhythmias are the most common cause of cardiac syncope.Both bradyarrhythmia and tachyarrhythmia can cause a sudden decrease in cardiac output and produce syncope.In this review,we summarized the main guidelines in the management of patients with syncope of presumed arrhythmic origin.Therefore,we presented a thorough approach to syncope work-up through different tests depending on the clinical characteristics of the patients,risk stratification,and the management of syncope in different scenarios such as structural heart disease and channelopathies.
文摘Background:To compare objective electrophysiological contrast sensitivity function(CSF)in patients implanted with either multifocal intraocular lenses(MIOLs)or monofocal intraocular lenses(IOLs)by pattern reversal visual evoked potentials(prVEP)measurements.Methods:Fourty-five cataract patients were randomly allocated to receive bilaterally:apodized diffractive-refractive Alcon Acrysof MIOL(A),full diffractive AMO Tecnis MIOL(B)or monofocal Alcon Acrysof IOL(C).Primary outcomes:1-year differences in objective binocular CSF measured by prVEP with sinusoid grating stimuli of 6 decreasing contrast levels at 6 spatial frequencies.Secondary outcomes:psychophysical CSF measured with VCTS-6500,photopic uncorrected distance(UDVA),and mesopic and photopic uncorrected near and intermediate visual acuities(UNVA and UIVA respectively).Results:Electrophysiological CSF curve had an inverted U-shaped morphology in all groups,with a biphasic pattern in Group B.Group A showed a lower CSF than group B at 4 and 8 cpd,and a lower value than group C at 8 cpd.Psychophysical CSF in group A exhibited a lower value at 12 cpd than group B.Mean photopic and mesopic UNVA and UIVA were worse in monofocal group compared to the multifocal groups.Mesopic UNVA and UIVA were better in group B.Conclusions:Electrophysiological CSF behaves differently depending on the types of multifocal or monofocal IOLs.This may be related to the visual acuity under certain conditions or to IOL characteristics.This objective method might be a potential new tool to investigate on MIOL differences and on subjective device-related quality of vision.
基金Acknowledgement This work supported by the National Basic Research Program of China （973 Program, 2008CB517303）, a grant from National Natural Science Foundation of China （30800464）, a grant of pivot talents of medicine of Jiangsu Province （RC2007040）, and a grant from Provincial Natu- ral Science of Jiangsu, China （BK2005218）
文摘Objective Chronic atrial fibrillation （AF） results in dedifferentiation of atrial cardiomyocytes that plays an important role in the perpetuation of AF. In this study, we aimed to investigate the changes oftitin and a-smooth muscle actin （α-SMA） after long time of AF reversal. Methods Twenty-four goats were randomized into four groups： （1） sinus rhythm （SR）, （2） 3 months AF （3-too AF）, （3） 3 months SR after 3 months AF （3-mo post AF）, （4） 6 months SR after 3-mo AF （6-mo post AF）, with 6 in each group. By pacing on the anterior bottom of left atria appendage （LAA）, we established a goat model of chronic AF. Atria effective refractory period （AERP） was measured with electrophysiological methods. Ultra-structure was studied with echocardiography, light and electron microscopy. Titin and α-SMA protein expressions were determined by Western blot. Results The animals underwent high rate pacing on LAA for a mean of 42.23± 21.70 days before presenting AF. Electrophysiological analysis revealed that AERP completely resumed in 3-mo post AF goats. Echocardiography displayed that the size of left atrium resumed almost in 6-too post AF goats （P〈 0.01）. Pathological and electron microscopic examination revealed the disorder of myofibrils, augmentation of intercellular space, myolysis, accumulation of glycogen, and numerous bigger mitochondria among atrial cardiomyocytes in 3-mo AF goats. They recovered mostly in 6-mo post AF goats. Western blot showed that the band density oftitin significantly reduced in 3-mo AF goats compared to SR ones [1826 ± 319 vs 5012±854, P 〈 0.01]. In 3- and 6-mo post AF goats, titin increased gradually and it reversed completely in 6-mo post AF goats （3841 ± 601 and 4523 ±833 respectively, P 〈 0.01）. Conversely, the band density ofa-SMAwas significantly higher in 3-mo AF goats （5324 ± 948） than in SR ones （1619 ±271, P 〈 0.01）. In 3- and 6-mo post-AF goats, α-SMA decreased gradually, and it recovered mostly in 6- mo p
