Background: Right ventricular (RV) dysfunction could develop during exercise in</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">pati...Background: Right ventricular (RV) dysfunction could develop during exercise in</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">patients with both hypertension and left ventricular diastolic dysfunction and may contribute to the patient symptoms. The objective is to assess RV function, both at rest and during exercise in patients with hypertension and left ventricular diastolic dysfunction. Methods: We included 30 patients with hypertension and resting LV diastolic dysfunction. The systolic function of the right ventricle was assessed by TAPSE (Tricuspid Annular Plane Systolic Excursion) and S</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> while E/A ratio, annular lateral E’, E/E’ and E’/A’ were used to measure diastolic function. The global function of the right ventricle was assessed by measuring the right indexed myocardial performance. The dimensions and pulmonary pressures were also measured. Results: The following parameters of RV systolic function were increased significantly with exercise: TAPSE (P = 0.0054), S’ (P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">= 0.0045). Moreover, the following diastolic parameters of the RV increased significantly with exercise: E/E’ (P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">=</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.05), A’</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">(P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">=</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.04). The global RV function showed also a significant increase (P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">=</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.0011). The three RV dimensions as well as the pulmonary artery pressures also increased during exercise (P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">= 0.000004, 0.001, and 0.00000064 respectively). In addition, the presence of resting LV grade II DD predicted significantly higher pulmonary pressures during exercise (</span><span style="font-family:Verdana;">P</span><span style="font-family:Verdana;"> =</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.006). The advanced resting grade of LVDD predicted significantly the presence of advanced grade of RVDD with exercise (</span><span style="font-family:Verdana;">P</span><span style="font-family:Verdana;"> =</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.037). Conclusions: Some patients who have both hypertension and LV diastolic dysfunction showed structural and functional changes of the right ventricle at rest. However, all patients had RV functional changes during exercise.展开更多
To measure the response of left and right ventricular ejection fraction and wall motion to exercise in eighteen patients with angiogl’aphically documented coronary artery disease (CAD) and in twenty-two patients with...To measure the response of left and right ventricular ejection fraction and wall motion to exercise in eighteen patients with angiogl’aphically documented coronary artery disease (CAD) and in twenty-two patients with angiographicallynormal coronary arteries using ultrafast computed tomography(UFCT). Methods: Angiography and UFCT exercise cine studieswere performed for the evaluation of chest pain in all 40 cases, including 18 CAD patients and 22 patients with normal coronary arteries. Results: Of the 18 patients with CAD, 14(78% ) had a≥5% decrease in left ventricular ejection fraction (LVEF) duringexercise by UFCT (P< 0 .001), and 14 (78%) had an abnormal response in left ventricular wall motion during exercise, (aworsened or newly-developed reginal RV wall motion abnormality (RVWMA)) during exercise. In the 22 normal patients, onlyone had a decrease in LVEF > 5%; none had an abnormal response in LV wall motion during peak exercise or a RVWMA at restor during stress. Using a decrease of ≥5 % in LVEF or a LVWMA or RVWMA during stress as a criterion for identifying patientswith CAD, the accuracy was 88% (35/40) with LVEF, 90% (36/40) with LVWMA, and 92% (37/40) with a combination ofLVEF, LVWMA and RVWMA. The sensitivity of RVWMA alone in detecting right coronary artery disease (RCAD) was 60%(6/10) and the specificity was 78% (7/9). Conclusion: Our study suggests that exercise-UFCT appears to be a useful tool for thedetection of CAD in patients with chest pain. The abnormal response of LVEF and exercise-induced LVWMA and RVWMA as determined by UFCT were important predictors CAD. Both LVWMA and RVWMA of important value in identifying patientswith CAN from those with normal coronary arteries, as is RVWMA in defining the existence of RCAD in patients with CAD.展开更多
Intense exercise may cause heart remodeling to compensate increases in blood pressure or volume by increasing muscle mass. Cardiac changes do not involve only the left ventricle, but all heart chambers. Physiological ...Intense exercise may cause heart remodeling to compensate increases in blood pressure or volume by increasing muscle mass. Cardiac changes do not involve only the left ventricle, but all heart chambers. Physiological cardiac modeling in athletes is associated with normal or enhanced cardiac function, but recent studies have documented decrements in left ventricular function during intense exercise and the release of cardiac markers of necrosis in athlete's blood of uncertain significance. Furthermore, cardiac remodeling may predispose athletes to heart disease and result in electrical remodeling, responsible for arrhythmias. Athlete's heart is a physiological condition and does not require a specific treatment. In some conditions, it is important to differentiate the physiological adaptations from pathological conditions, such as hypertrophic cardiomyopathy, arrhythmogenic dysplasia of the right ventricle, and non-compaction myocardium, for the greater risk of sudden cardiac death of these conditions. Moreover, some drugs and performance-enhancing drugs can cause structural alterations and arrhythmias, therefore, their use should be excluded.展开更多
BACKGROUND Arrhythmogenic right ventricular(RV)cardiomyopathy is a rare and currently underrecognized cardiomyopathy characterized by the replacement of RV myocardium by fibrofatty tissue.It may be asymptomatic or sym...BACKGROUND Arrhythmogenic right ventricular(RV)cardiomyopathy is a rare and currently underrecognized cardiomyopathy characterized by the replacement of RV myocardium by fibrofatty tissue.It may be asymptomatic or symptomatic(palpitations or syncope)and may induce sudden cardiac death,especially during exercise.To prevent adverse events such as sudden cardiac death and heart failure,early diagnosis and treatment of arrhythmogenic RV cardiomyopathy(ARVC)are crucial.We report a patient with ARVC characterized by recurrent syncope during exercise who was successfully treated with combined endocardial and epicardial catheter ablation.CASE SUMMARY A 43-year-old man was referred for an episode of syncope during exercise.Previously,the patient experienced two episodes of syncope without a firm etiological diagnosis.An electrocardiogram obtained at admission indicated ventricular tachycardia originating from the inferior wall of the right ventricle.The ventricular tachycardia was terminated with intravenous propafenone.A repeat electrocardiogram showed a regular sinus rhythm with negative T waves and a delayed S-wave upstroke from leads V1 to V4.Cardiac magnetic resonance imaging showed RV free wall thinning,regional RV akinesia,RV dilatation and fibrofatty infiltration(RV ejection fraction of 38%).An electrophysiological study showed multiple inducible ventricular tachycardia as of a focal mechanism from the right ventricle.Endocardial and epicardial voltage mapping demonstrated scar tissue in the anterior wall,free wall and posterior wall of the right ventricle.Late potentials were also recorded.The patient was diagnosed with ARVC and treated with combined endocardial and epicardial catheter ablation with a very satisfactory follow-up result.CONCLUSION Clinicians should be aware of ARVC,and further workup,including imaging with multiple modalities,should be pursued.The combination of epicardial and endocardial catheter ablation can lead to a good outcome.展开更多
心理学家认为基于绩效的财务激励损害企业创造力,本文证实绩效薪酬制度对企业创新的影响取决于其结构,结构合理的绩效薪酬制度也能够促进企业创新。具体而言,本文利用中国上市公司2006-2014年股权激励计划的详细数据,研究业绩型股权激...心理学家认为基于绩效的财务激励损害企业创造力,本文证实绩效薪酬制度对企业创新的影响取决于其结构,结构合理的绩效薪酬制度也能够促进企业创新。具体而言,本文利用中国上市公司2006-2014年股权激励计划的详细数据,研究业绩型股权激励及其行权限制特征对企业创新活动的影响。本文发现,整体而言,业绩型股权激励有助于激发企业创新。相对于非股权激励公司,股权激励公司的研发投入和专利申请数量分别高4 0%和4 6.2%。更重要的是,股权激励对企业创新活动的促进作用受到股权激励计划行权限制特征的影响。行权时间限制能够提升股权激励效应,股权激励久期增加一年能相应增加15%的研发投入和18.3%的专利申请数量;但行权业绩考核会抑制企业创新,经行业调整的R O E目标增加一个标准差会使企业研发投入下降5%,专利申请数量下降8.39%。这些发现说明,管理层对短期业绩的关注是绩效薪酬损害企业创新活力的主要原因。展开更多
目的:通过建立长期大强度运动模型,研究长期不同强度耐力运动对大鼠右心室心功能和羟脯氨酸的含量影响以及基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2)和金属蛋白酶抑制剂2(tissue inhibitor of metalloproteinase-2,TIMP-2)的...目的:通过建立长期大强度运动模型,研究长期不同强度耐力运动对大鼠右心室心功能和羟脯氨酸的含量影响以及基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2)和金属蛋白酶抑制剂2(tissue inhibitor of metalloproteinase-2,TIMP-2)的调节作用,为运动性心肌纤维化和心律失常的发生机制提供实验依据。方法:24只健康成年雄性SD大鼠随机分为安静对照组、中强度运动组和大强度运动组,每组8只。中强度组和大强度组进行16周的运动,每周训练5天,休息2天,每次1 h。16周后采用小动物超声心动仪检测大鼠右心室心功能。随后,立刻麻醉处死大鼠,摘取心脏,分离出右心室。采用样本碱水解法检测羟脯氨酸的含量;荧光定量PCR检测MMP-2和TIMP-2 m RNA的相对表达。Western Blot检测MMP-2和TIMP-2蛋白的表达。结果:(1)与安静组相比,中强度组右室射血分数(RVEF)和右室缩短分数(RVFS)增加,但无显著性差异。大强度组RVEF显著低于安静组和中强度组(P<0.05),大强度组RVFS均低于安静组和中强度组,但无显著性差异。(2)中强度组羟脯氨酸的含量高于安静对照组,但无显著性差异;而大强度组羟脯氨酸的含量显著高于安静组和中强度组(P<0.01)。(3)与安静组相比,中强度组MMP-2 m RNA和蛋白的表达具有增加趋势,但无显著性差异。大强度组MMP-2 m RNA的表达显著高于安静组(P<0.05),大强度组MMP-2蛋白的表达显著高于安静组和中强度组(P<0.01);与安静组比较,中强度组和大强度组TIMP-2 m RNA的表达均无显著性差异;通过计算发现,三组间MMP-2/TIMP-2m RNA的比值无明显差异,大强度组MMP-2/TIMP-2蛋白的比值显著高于安静组和中强度组(P<0.01)。结论:长期大强度运动造成大鼠右心室羟脯氨酸含量显著增加,心肌MMP-2的表达增加,MMP-2/TIMP-2比例失调可能是右心室心功能异常和运动性心肌纤维化的发生机制之一。展开更多
文摘Background: Right ventricular (RV) dysfunction could develop during exercise in</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">patients with both hypertension and left ventricular diastolic dysfunction and may contribute to the patient symptoms. The objective is to assess RV function, both at rest and during exercise in patients with hypertension and left ventricular diastolic dysfunction. Methods: We included 30 patients with hypertension and resting LV diastolic dysfunction. The systolic function of the right ventricle was assessed by TAPSE (Tricuspid Annular Plane Systolic Excursion) and S</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> while E/A ratio, annular lateral E’, E/E’ and E’/A’ were used to measure diastolic function. The global function of the right ventricle was assessed by measuring the right indexed myocardial performance. The dimensions and pulmonary pressures were also measured. Results: The following parameters of RV systolic function were increased significantly with exercise: TAPSE (P = 0.0054), S’ (P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">= 0.0045). Moreover, the following diastolic parameters of the RV increased significantly with exercise: E/E’ (P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">=</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.05), A’</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">(P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">=</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.04). The global RV function showed also a significant increase (P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">=</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.0011). The three RV dimensions as well as the pulmonary artery pressures also increased during exercise (P</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">= 0.000004, 0.001, and 0.00000064 respectively). In addition, the presence of resting LV grade II DD predicted significantly higher pulmonary pressures during exercise (</span><span style="font-family:Verdana;">P</span><span style="font-family:Verdana;"> =</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.006). The advanced resting grade of LVDD predicted significantly the presence of advanced grade of RVDD with exercise (</span><span style="font-family:Verdana;">P</span><span style="font-family:Verdana;"> =</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">0.037). Conclusions: Some patients who have both hypertension and LV diastolic dysfunction showed structural and functional changes of the right ventricle at rest. However, all patients had RV functional changes during exercise.
文摘To measure the response of left and right ventricular ejection fraction and wall motion to exercise in eighteen patients with angiogl’aphically documented coronary artery disease (CAD) and in twenty-two patients with angiographicallynormal coronary arteries using ultrafast computed tomography(UFCT). Methods: Angiography and UFCT exercise cine studieswere performed for the evaluation of chest pain in all 40 cases, including 18 CAD patients and 22 patients with normal coronary arteries. Results: Of the 18 patients with CAD, 14(78% ) had a≥5% decrease in left ventricular ejection fraction (LVEF) duringexercise by UFCT (P< 0 .001), and 14 (78%) had an abnormal response in left ventricular wall motion during exercise, (aworsened or newly-developed reginal RV wall motion abnormality (RVWMA)) during exercise. In the 22 normal patients, onlyone had a decrease in LVEF > 5%; none had an abnormal response in LV wall motion during peak exercise or a RVWMA at restor during stress. Using a decrease of ≥5 % in LVEF or a LVWMA or RVWMA during stress as a criterion for identifying patientswith CAD, the accuracy was 88% (35/40) with LVEF, 90% (36/40) with LVWMA, and 92% (37/40) with a combination ofLVEF, LVWMA and RVWMA. The sensitivity of RVWMA alone in detecting right coronary artery disease (RCAD) was 60%(6/10) and the specificity was 78% (7/9). Conclusion: Our study suggests that exercise-UFCT appears to be a useful tool for thedetection of CAD in patients with chest pain. The abnormal response of LVEF and exercise-induced LVWMA and RVWMA as determined by UFCT were important predictors CAD. Both LVWMA and RVWMA of important value in identifying patientswith CAN from those with normal coronary arteries, as is RVWMA in defining the existence of RCAD in patients with CAD.
文摘Intense exercise may cause heart remodeling to compensate increases in blood pressure or volume by increasing muscle mass. Cardiac changes do not involve only the left ventricle, but all heart chambers. Physiological cardiac modeling in athletes is associated with normal or enhanced cardiac function, but recent studies have documented decrements in left ventricular function during intense exercise and the release of cardiac markers of necrosis in athlete's blood of uncertain significance. Furthermore, cardiac remodeling may predispose athletes to heart disease and result in electrical remodeling, responsible for arrhythmias. Athlete's heart is a physiological condition and does not require a specific treatment. In some conditions, it is important to differentiate the physiological adaptations from pathological conditions, such as hypertrophic cardiomyopathy, arrhythmogenic dysplasia of the right ventricle, and non-compaction myocardium, for the greater risk of sudden cardiac death of these conditions. Moreover, some drugs and performance-enhancing drugs can cause structural alterations and arrhythmias, therefore, their use should be excluded.
基金Natural Science Basic Research Program of Shaanxi Province,No.2020JQ-939and Science and Technology Development Incubation Fund Project of Shaanxi Provincial People’s Hospital,No.2019YXQ-08.
文摘BACKGROUND Arrhythmogenic right ventricular(RV)cardiomyopathy is a rare and currently underrecognized cardiomyopathy characterized by the replacement of RV myocardium by fibrofatty tissue.It may be asymptomatic or symptomatic(palpitations or syncope)and may induce sudden cardiac death,especially during exercise.To prevent adverse events such as sudden cardiac death and heart failure,early diagnosis and treatment of arrhythmogenic RV cardiomyopathy(ARVC)are crucial.We report a patient with ARVC characterized by recurrent syncope during exercise who was successfully treated with combined endocardial and epicardial catheter ablation.CASE SUMMARY A 43-year-old man was referred for an episode of syncope during exercise.Previously,the patient experienced two episodes of syncope without a firm etiological diagnosis.An electrocardiogram obtained at admission indicated ventricular tachycardia originating from the inferior wall of the right ventricle.The ventricular tachycardia was terminated with intravenous propafenone.A repeat electrocardiogram showed a regular sinus rhythm with negative T waves and a delayed S-wave upstroke from leads V1 to V4.Cardiac magnetic resonance imaging showed RV free wall thinning,regional RV akinesia,RV dilatation and fibrofatty infiltration(RV ejection fraction of 38%).An electrophysiological study showed multiple inducible ventricular tachycardia as of a focal mechanism from the right ventricle.Endocardial and epicardial voltage mapping demonstrated scar tissue in the anterior wall,free wall and posterior wall of the right ventricle.Late potentials were also recorded.The patient was diagnosed with ARVC and treated with combined endocardial and epicardial catheter ablation with a very satisfactory follow-up result.CONCLUSION Clinicians should be aware of ARVC,and further workup,including imaging with multiple modalities,should be pursued.The combination of epicardial and endocardial catheter ablation can lead to a good outcome.
文摘心理学家认为基于绩效的财务激励损害企业创造力,本文证实绩效薪酬制度对企业创新的影响取决于其结构,结构合理的绩效薪酬制度也能够促进企业创新。具体而言,本文利用中国上市公司2006-2014年股权激励计划的详细数据,研究业绩型股权激励及其行权限制特征对企业创新活动的影响。本文发现,整体而言,业绩型股权激励有助于激发企业创新。相对于非股权激励公司,股权激励公司的研发投入和专利申请数量分别高4 0%和4 6.2%。更重要的是,股权激励对企业创新活动的促进作用受到股权激励计划行权限制特征的影响。行权时间限制能够提升股权激励效应,股权激励久期增加一年能相应增加15%的研发投入和18.3%的专利申请数量;但行权业绩考核会抑制企业创新,经行业调整的R O E目标增加一个标准差会使企业研发投入下降5%,专利申请数量下降8.39%。这些发现说明,管理层对短期业绩的关注是绩效薪酬损害企业创新活力的主要原因。
文摘目的:通过建立长期大强度运动模型,研究长期不同强度耐力运动对大鼠右心室心功能和羟脯氨酸的含量影响以及基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2)和金属蛋白酶抑制剂2(tissue inhibitor of metalloproteinase-2,TIMP-2)的调节作用,为运动性心肌纤维化和心律失常的发生机制提供实验依据。方法:24只健康成年雄性SD大鼠随机分为安静对照组、中强度运动组和大强度运动组,每组8只。中强度组和大强度组进行16周的运动,每周训练5天,休息2天,每次1 h。16周后采用小动物超声心动仪检测大鼠右心室心功能。随后,立刻麻醉处死大鼠,摘取心脏,分离出右心室。采用样本碱水解法检测羟脯氨酸的含量;荧光定量PCR检测MMP-2和TIMP-2 m RNA的相对表达。Western Blot检测MMP-2和TIMP-2蛋白的表达。结果:(1)与安静组相比,中强度组右室射血分数(RVEF)和右室缩短分数(RVFS)增加,但无显著性差异。大强度组RVEF显著低于安静组和中强度组(P<0.05),大强度组RVFS均低于安静组和中强度组,但无显著性差异。(2)中强度组羟脯氨酸的含量高于安静对照组,但无显著性差异;而大强度组羟脯氨酸的含量显著高于安静组和中强度组(P<0.01)。(3)与安静组相比,中强度组MMP-2 m RNA和蛋白的表达具有增加趋势,但无显著性差异。大强度组MMP-2 m RNA的表达显著高于安静组(P<0.05),大强度组MMP-2蛋白的表达显著高于安静组和中强度组(P<0.01);与安静组比较,中强度组和大强度组TIMP-2 m RNA的表达均无显著性差异;通过计算发现,三组间MMP-2/TIMP-2m RNA的比值无明显差异,大强度组MMP-2/TIMP-2蛋白的比值显著高于安静组和中强度组(P<0.01)。结论:长期大强度运动造成大鼠右心室羟脯氨酸含量显著增加,心肌MMP-2的表达增加,MMP-2/TIMP-2比例失调可能是右心室心功能异常和运动性心肌纤维化的发生机制之一。
