Objective:To assess the effect of angiotensin II type 1(AT1)receptor antagonist losartan on myocardium con- nexin43(Cx43)gap junction(GJ)expression in spontaneously hypertensive rats(SHRs)and investigate possible mech...Objective:To assess the effect of angiotensin II type 1(AT1)receptor antagonist losartan on myocardium con- nexin43(Cx43)gap junction(GJ)expression in spontaneously hypertensive rats(SHRs)and investigate possible mechanisms. Methods:Sixteen 9-week-old male SHRs and 8 age-matched male Wistar-Kyoto(WKY)rats were included in this study.SHRs were randomly divided into two groups to receive losartan at 30 mg/(kg·d)by oral gavage once daily for 8 weeks(SHR-L)or vehicle(0.9%saline)to act as controls(SHR-V);WKY rats receiving vehicle for 8 weeks served as normotensive controls.At the end of the experiment,rats were sacrificed and the hearts were removed.Expressions of Cx43 and nuclear factor-kappaB p65 (NF-κB p65)proteins in all three groups were observed and further investigations on the effect of angiotensin II type 1 receptor antagonist losartan(30 mg/(kg·d),8 weeks)on Cx43 expression were conducted with Western blot and immunohistochemistry. NF-κB p65 protein in nuclear extracts was determined by Western blot.Results:Left ventricular(LV)hypertrophy was prominent in SHRs,Cx43 and NF-κB p65 protein expressions were obviously upregulated and Cx43 distribution was dispersed over the cell surface.Treatment with losarton reduced the over-expressions of Cx43 and NF-κB p65 in LV myocardium.The distribution of Cx43 gap junction also became much regular and confined to intercalated disk after losartan treatment.Conclu- sion:Cx43 level was upregulated in LV myocardium of SHR during early stage of hypertrophy.Angiotensin II type 1 receptor antagonist losartan prevented Cx43 gap junction remodeling in hypertrophied left ventricles,possibly through the NF-κB pathway.展开更多
Objective To evaluate the efficacy and safety of long-term treatment with arotinolol in patients with idiopathic dilated cardiomyopathy(IDCM).Methods Sixty-three patients with IDCM were evaluated at baseline and after...Objective To evaluate the efficacy and safety of long-term treatment with arotinolol in patients with idiopathic dilated cardiomyopathy(IDCM).Methods Sixty-three patients with IDCM were evaluated at baseline and after 12-month therapy with arotinolol.The conventional therapy for congestive heart failure was continued throughout the study with arotinolol as the only β-blocker.Left ventricular function was assessed with the New York Heart Association functional class and two-dimensional echocardiography.Results After 12-month arotinolol treatment,there was a significant improvement in left ventricular systolic function.Left ventricular end-systolic dimension significantly decreased from 59.52±8.83 mm to 50.89±8.17 mm(P<0.001).Left ventricular ejection fraction significantly increased from 27.39%±7.94% to 41.13%±9.45%(P<0.001).Left ventricular mass index decreased from 150.47±42.42 g/m2 to 141.58±34.36 g/m2(P<0.01).No adverse events leading to premature discontinuation of study drug occurred.Conclusion In this preliminary study,12-month arotinolol treatment has a favorable effect on left ventricular function in patients with IDCM,and it is safe and well tolerated.展开更多
Objectives To establish a cost-effective and reproducible procedure for induction of chronic left ventricular aneurysm （LVA） in rabbits. Methods Acute myocardial infarction （AMI） was induced in 35 rabbits via conc...Objectives To establish a cost-effective and reproducible procedure for induction of chronic left ventricular aneurysm （LVA） in rabbits. Methods Acute myocardial infarction （AMI） was induced in 35 rabbits via concomitant ligation of the left anterior descending （LAD） coronary artery and the circumflex （Cx） branch at the middle portion. Development of AMI was co n-firmed by ST segment elevation and akinesis of the occluded area. Echocardiography, pathological evaluation, and agar i n-tra-chamber casting were utilized to validate the formation of LVA four weeks after the surgery. Left ventricular end systolic pressure （LVESP） and diastolic pressure （LVEDP） were measured before, immediately after and four weeks after ligation. D i-mensions of the ventricular chamber, thickness of the interventricular septum （IVS） and the left ventricular posterior wall （LVPW） left ventricular end diastolic volume （LVEDV） and systolic volume （LVESV）, and ejection fraction （EF） were recorded by echo-cardiography. Results Thirty one （88.6%） rabbits survived myocardial infarction and 26 of them developed aneurysm （83.9%）. The mean area of aneurysm was 33.4% ＆#177; 2.4% of the left ventricle. LVEF markedly decreased after LVA formation, whereas LVEDV, LVESV and the thickness of IVS as well as the dimension of ventricular chamber from apex to mitral valve annulus significantly increased. LVESP immediately dropped after ligation and recovered to a small extent after LVA formation. LVEDP progressively increased after ligation till LVA formation. Areas in the left ventricle （LV） that underwent fibrosis included the apex, anterior wall and lateral wall but not IVS. Agar intra-chamber cast showed that the bulging of LV wall was prominent in the area of aneurysm. Conclusions Ligation of LAD and Cx at the middle portion could induce develo pment of LVA at a mean area ratio of 33.4%＆#177;2.4%which involves the apex, anterior wall and lateral wall of the LV.展开更多
Papillary fibroelastoma cardiac tumor. The most is the most common valvular common non-valvular site these minors present is the left ventricle, where they usually manifest as ischemic strokes or myocardial infarction...Papillary fibroelastoma cardiac tumor. The most is the most common valvular common non-valvular site these minors present is the left ventricle, where they usually manifest as ischemic strokes or myocardial infarction. Although these tumors also have a risk of embolization into the peripheral system, reports of such events are exceedingly rare.展开更多
We describe a rare case of a 60-year-old woman suffering from intramyocardial dissection and left ventricular aneurysm secondary to acute myocardial infarction. A rare form of ventricular septal rupture resulted from ...We describe a rare case of a 60-year-old woman suffering from intramyocardial dissection and left ventricular aneurysm secondary to acute myocardial infarction. A rare form of ventricular septal rupture resulted from intramyocardial dissection deterioration, which was iden- tified during echocardiographic follow-up. Surgical repair under beating-heart cardiopulmonary bypass was successful.展开更多
Objectives. To compare the effects of losartan, enalapril and their combination in the prevention ofleft ventricular remodeling (LVRM) after acute myocardial infarction (AMI) in the rat. Methods. AMI model was induced...Objectives. To compare the effects of losartan, enalapril and their combination in the prevention ofleft ventricular remodeling (LVRM) after acute myocardial infarction (AMI) in the rat. Methods. AMI model was induced in female SD rats by ligating left coronary artery. Forty-eight hours after the procedure, 83 surviving rats were randomized into one of the following 4 groups: 1 ) AMI control group (n =19), 2) losartan group (n= 22, 3 mg @ kg - 1 @ d - 1 ), 3 ) enalapril group (n = 20, 1 mg @ kg - 1 @ d - 1 ), 4) losartan - enalapril combinative group (n = 22, 3 and 1 mg @ kg- 1 @ d - 1 respectively). 5 ) sham-operated group ( n =10) and 6) normal rats group (n = 10) were selected randomly to serve as non-infarction controls. Losartan and enalapril were delivered by direct gastric gavage. After 4 weeks of medical therapy, hemodynamic studies were performed in each group, then the rat hearts were fixed with 10% formalin and pathologic analysis on them was performed. Complete experimental data was obtained in 56 rats, comprising 1 ) AMI controls (n = 11 ), 2) losartan group (n = 10), 3 ) enalapril group (n = 10), 4) the combination of losartan and enalapril group (n = 11 ),5) sham - operated group (n = 6) and 6) normal controls (n=8). Results. There were no significant differences among the 4 AMI groups in MI size (41.7% ～ 43.4%, all P＞ 0.05). Compared with sham group, the left ventricular (LV) end diastolic pressure (LVEDP), volume (LVV), long and short axis length (L and D), as well as LV absolute and relative weight (LVAW and LVRW)in AMI group were all significantly increased ( P ＜0.05 ～ 0. 001 ); whereas the maximum left ventricular pressure rising and droping rates ( + dp/dt) and their corrected values by LV systolic pressure ( + dp/dt/LVSP)were significantly reduced (all P ＜0.001 ), indicating LVRM occurred and LV systolic and diastolic function impaired after AMI. Compared with AMI group , LVEDP, LVV, LVAW and LVRW were all significantly decreased (P ＜0.05～0.001 ); while + dp/dt/LVSP were significantly enhanced in all 3 treatment groups (P ＜0.05～0.001 ) except -dp/dt/LVSP in losartan group (P＞ 0. 05 ). There were no significant differences in the above indices among the 3 treatment groups (all P＞ 0.05). Conclusion. Both losartan and enalapril can prevent from LVRM after AMI in the rat and improve LV function with equivalent effects. There seems no additive effect when the 2 drugs are used in combination.展开更多
OBJECTIVE: To compare the effects of high, middle and low doses of enalapril in preventing left ventricular remodeling (LVRM) after acute myocardial infarction (AMI) in rats, especially evaluating the efficacy of low ...OBJECTIVE: To compare the effects of high, middle and low doses of enalapril in preventing left ventricular remodeling (LVRM) after acute myocardial infarction (AMI) in rats, especially evaluating the efficacy of low dose enalapril. METHODS: AMI was induced by ligating the left coronary artery in 149 female SD rats. 48 hours after the procedure, the 97 surviving rats were randomized to one of the following four groups: (1) AMI controls (n = 24), (2) high-dose (10 mg x kg(-1) x d(-1), n = 25), (3) middle-dose (1 mg x kg(-1) x d(-1), n = 23), and (4) low-dose (0.1 mg x kg(-1) x d(-1), n = 25) enalapril groups. In addition, sham-operated (n = 13) and normal rats (n = 10) were randomly selected to serve as non-infarction controls. Enalapril was delivered by direct gastric gavage. After 4 weeks of therapy, hemodynamic studies were performed, then the rat hearts were fixed with 10% formalin and pathology analysis was performed. Exclusive of the dead rats and those with MI size 55%, complete experimental data were obtained from 67 rats, which were comprised of (1) AMI controls (n = 13), (2) high-dose enalapril (n = 13), (3) middle-dose enalapril (n = 12), (4) low-dose enalapril (n = 12), (5) sham-operated (n = 8) and (6) normal (n = 9) groups. RESULTS: There were no significant differences among the four AMI groups in infarction size (all P > 0.05). Compared with the sham-operated group, the left ventricular (LV) end diastolic pressure (LVEDP), volume (LVV), absolute and relative weight (LVAW, LVRW) in AMI group were all significantly increased (all P展开更多
Objective To explore the molecular mechanism underlying the decreased velocity of tension rise in rat myocardium during congestive heart failure (CHF) and left ventricular hypertrophy (LVH) induced by aortic stenosis...Objective To explore the molecular mechanism underlying the decreased velocity of tension rise in rat myocardium during congestive heart failure (CHF) and left ventricular hypertrophy (LVH) induced by aortic stenosis.Methods The maximum velocity of tension rise (+dT/dtmax) was measured in left ventricular papillary muscle and the mRNA level of myosin heavy chain (MHC) isoforms in the left ventricle were detected by Northern blot analysis.Results The value of +dT/dtmax in CHF and LVH group were 64.17% and 37.15% lower than sham-operated controls (Sham) (P<0.01); values in the CHF group were 42.99% lower than that of LVH (P<0.01). The level of α-MHC mRNA in LVH was not different from that of the Sham (P>0.05), but decreased significantly in CHF to 42.3% of Sham and 56.1% of LVH (P<0.01). The level of β-MHC mRNA was up-regulated by 88.3% (P<0.01) in LVH compared with Sham and the level of β-MHC in CHF was 1.5-fold and 3.7-fold higher than that in LVH and Sham respectively (P<0.01). The ratio of α-MHC/β-MHC mRNA in LVH and CHF decreased to 42.4% and 9.8% respectively of the value in Sham (P<0.01). Correlation between α-MHC/β-MHC mRNA level and +dT/dtmax was analyzed which showed that these values were positively correlated with a correlation coefficient of 0.875 (P<0.01).Conclusion The decreased ratio of α-MHC/β-MHC mRNA was the major molecular mechanism underlying the decreased +dT/dtmax in CHF and LVH myocardium. The decreased ratio of α-MHC/β-MHC mRNA in LVH was mainly due to the up regulation of β-MHC mRNA while in CHF both down regulation of α-MHC and up regulation of β-MHC were involved.展开更多
Objective To evaluate the immediate and follow-up results of percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy (HOCM). Methods Fifteen symptomatic...Objective To evaluate the immediate and follow-up results of percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy (HOCM). Methods Fifteen symptomatic, drug-refractory patients with HOCM underwent PTSMA procedures with application of a myocardial contrast echocardiography (MCE) intra-procedure. Before and after the procedure, clinical evaluations were obtained in all patients, who were followed up for a mean period of 8.6±3.8 (6-20) months.Results Immediate left ventricular outflow tract gradient (LVOTG) reduction was achieved (77.93±22?mm?Hg vs 14.8±15?mm?Hg, P【0.0001) after the procedure with a mean decrease of 5.75±2.87?mm?Hg of left ventricular end diastolic pressure (P【0.001). Follow up results revealed that ventricular remodelling occurred mainly 1-3 months after the procedure, but without evidence of ventricular dilation and contract dysfunction. Heart function (NYHA) was greatly improved (3.4±0.5 vs 1.1±0.4, P【0.001) and exercise endurance increased. A renewed increase of LVOTG was found in 2 patients during follow-up. Conclusions LVOTG was greatly decreased in HOCM patients undergoing a PTSMA procedure, and their symptoms were greatly improved without cardiac complications during follow-up. Sub-selection and re-opening of target vessels were the causes of renewed increase of LVOTG, and this can be avoided with the accumulation of experience. This is a promising method for the treatment of symptomatic patients with HOCM.展开更多
In the present study,we aimed to explore the protective effect of spironolactone on cardiac function in patients undergoing coronary stent implantation by determining the serum levels of GATA4 and hypoxia-inducible fa...In the present study,we aimed to explore the protective effect of spironolactone on cardiac function in patients undergoing coronary stent implantation by determining the serum levels of GATA4 and hypoxia-inducible factor-1α(HIF-1α)proteins before and after the coronary stent implantation.A total of 134 patients undergoing coronary stent implantation in our hospital from March 2019 to March 2020 were retrospectively selected using the propensity score matching(PSM)method.Of the 134 patients,67 patients taking spironolactone were used as a test group,and the other 67 patients without taking spironolactone were used as a control group.In all patients,the levels of serum GATA4,HIF-1α,and troponin I proteins were determined before as well as 24 h and 6 months after the coronary stent implantation.Left ventricular ejection fraction(LVEF)and left ventricular systolic global longitudinal strain(GLS)were determined before and 6 months after the coronary stent implantation.There were no significant differences in the HIF-1αlevel between the two groups before and 6 months after the operation,while the HIF-1αlevel was significantly lower in the test group compared with the control group at 24 h after the operation(P<0.01).There were no significant differences in the GATA4 protein level between the two groups before and 24 h after the operation,while the GATA4 protein level was significantly lower in the test group compared with the control group at 6 months after the operation(P<0.01).There was no significant difference in LVEF between the two groups before and 6 months after the operation.GLS was significantly improved at 6 months after the operation compared with that before the operation in both groups,while GLS was significantly better in the test group compared with the control group at 6 months after the operation(P<0.01).Collectively,spironolactone could protect cardiac function probably by improving myocardial hypoxia and inhibiting myocardial remodeling.展开更多
文摘Objective:To assess the effect of angiotensin II type 1(AT1)receptor antagonist losartan on myocardium con- nexin43(Cx43)gap junction(GJ)expression in spontaneously hypertensive rats(SHRs)and investigate possible mechanisms. Methods:Sixteen 9-week-old male SHRs and 8 age-matched male Wistar-Kyoto(WKY)rats were included in this study.SHRs were randomly divided into two groups to receive losartan at 30 mg/(kg·d)by oral gavage once daily for 8 weeks(SHR-L)or vehicle(0.9%saline)to act as controls(SHR-V);WKY rats receiving vehicle for 8 weeks served as normotensive controls.At the end of the experiment,rats were sacrificed and the hearts were removed.Expressions of Cx43 and nuclear factor-kappaB p65 (NF-κB p65)proteins in all three groups were observed and further investigations on the effect of angiotensin II type 1 receptor antagonist losartan(30 mg/(kg·d),8 weeks)on Cx43 expression were conducted with Western blot and immunohistochemistry. NF-κB p65 protein in nuclear extracts was determined by Western blot.Results:Left ventricular(LV)hypertrophy was prominent in SHRs,Cx43 and NF-κB p65 protein expressions were obviously upregulated and Cx43 distribution was dispersed over the cell surface.Treatment with losarton reduced the over-expressions of Cx43 and NF-κB p65 in LV myocardium.The distribution of Cx43 gap junction also became much regular and confined to intercalated disk after losartan treatment.Conclu- sion:Cx43 level was upregulated in LV myocardium of SHR during early stage of hypertrophy.Angiotensin II type 1 receptor antagonist losartan prevented Cx43 gap junction remodeling in hypertrophied left ventricles,possibly through the NF-κB pathway.
文摘Objective To evaluate the efficacy and safety of long-term treatment with arotinolol in patients with idiopathic dilated cardiomyopathy(IDCM).Methods Sixty-three patients with IDCM were evaluated at baseline and after 12-month therapy with arotinolol.The conventional therapy for congestive heart failure was continued throughout the study with arotinolol as the only β-blocker.Left ventricular function was assessed with the New York Heart Association functional class and two-dimensional echocardiography.Results After 12-month arotinolol treatment,there was a significant improvement in left ventricular systolic function.Left ventricular end-systolic dimension significantly decreased from 59.52±8.83 mm to 50.89±8.17 mm(P<0.001).Left ventricular ejection fraction significantly increased from 27.39%±7.94% to 41.13%±9.45%(P<0.001).Left ventricular mass index decreased from 150.47±42.42 g/m2 to 141.58±34.36 g/m2(P<0.01).No adverse events leading to premature discontinuation of study drug occurred.Conclusion In this preliminary study,12-month arotinolol treatment has a favorable effect on left ventricular function in patients with IDCM,and it is safe and well tolerated.
文摘Objectives To establish a cost-effective and reproducible procedure for induction of chronic left ventricular aneurysm （LVA） in rabbits. Methods Acute myocardial infarction （AMI） was induced in 35 rabbits via concomitant ligation of the left anterior descending （LAD） coronary artery and the circumflex （Cx） branch at the middle portion. Development of AMI was co n-firmed by ST segment elevation and akinesis of the occluded area. Echocardiography, pathological evaluation, and agar i n-tra-chamber casting were utilized to validate the formation of LVA four weeks after the surgery. Left ventricular end systolic pressure （LVESP） and diastolic pressure （LVEDP） were measured before, immediately after and four weeks after ligation. D i-mensions of the ventricular chamber, thickness of the interventricular septum （IVS） and the left ventricular posterior wall （LVPW） left ventricular end diastolic volume （LVEDV） and systolic volume （LVESV）, and ejection fraction （EF） were recorded by echo-cardiography. Results Thirty one （88.6%） rabbits survived myocardial infarction and 26 of them developed aneurysm （83.9%）. The mean area of aneurysm was 33.4% ＆#177; 2.4% of the left ventricle. LVEF markedly decreased after LVA formation, whereas LVEDV, LVESV and the thickness of IVS as well as the dimension of ventricular chamber from apex to mitral valve annulus significantly increased. LVESP immediately dropped after ligation and recovered to a small extent after LVA formation. LVEDP progressively increased after ligation till LVA formation. Areas in the left ventricle （LV） that underwent fibrosis included the apex, anterior wall and lateral wall but not IVS. Agar intra-chamber cast showed that the bulging of LV wall was prominent in the area of aneurysm. Conclusions Ligation of LAD and Cx at the middle portion could induce develo pment of LVA at a mean area ratio of 33.4%＆#177;2.4%which involves the apex, anterior wall and lateral wall of the LV.
文摘Papillary fibroelastoma cardiac tumor. The most is the most common valvular common non-valvular site these minors present is the left ventricle, where they usually manifest as ischemic strokes or myocardial infarction. Although these tumors also have a risk of embolization into the peripheral system, reports of such events are exceedingly rare.
文摘We describe a rare case of a 60-year-old woman suffering from intramyocardial dissection and left ventricular aneurysm secondary to acute myocardial infarction. A rare form of ventricular septal rupture resulted from intramyocardial dissection deterioration, which was iden- tified during echocardiographic follow-up. Surgical repair under beating-heart cardiopulmonary bypass was successful.
文摘Objectives. To compare the effects of losartan, enalapril and their combination in the prevention ofleft ventricular remodeling (LVRM) after acute myocardial infarction (AMI) in the rat. Methods. AMI model was induced in female SD rats by ligating left coronary artery. Forty-eight hours after the procedure, 83 surviving rats were randomized into one of the following 4 groups: 1 ) AMI control group (n =19), 2) losartan group (n= 22, 3 mg @ kg - 1 @ d - 1 ), 3 ) enalapril group (n = 20, 1 mg @ kg - 1 @ d - 1 ), 4) losartan - enalapril combinative group (n = 22, 3 and 1 mg @ kg- 1 @ d - 1 respectively). 5 ) sham-operated group ( n =10) and 6) normal rats group (n = 10) were selected randomly to serve as non-infarction controls. Losartan and enalapril were delivered by direct gastric gavage. After 4 weeks of medical therapy, hemodynamic studies were performed in each group, then the rat hearts were fixed with 10% formalin and pathologic analysis on them was performed. Complete experimental data was obtained in 56 rats, comprising 1 ) AMI controls (n = 11 ), 2) losartan group (n = 10), 3 ) enalapril group (n = 10), 4) the combination of losartan and enalapril group (n = 11 ),5) sham - operated group (n = 6) and 6) normal controls (n=8). Results. There were no significant differences among the 4 AMI groups in MI size (41.7% ～ 43.4%, all P＞ 0.05). Compared with sham group, the left ventricular (LV) end diastolic pressure (LVEDP), volume (LVV), long and short axis length (L and D), as well as LV absolute and relative weight (LVAW and LVRW)in AMI group were all significantly increased ( P ＜0.05 ～ 0. 001 ); whereas the maximum left ventricular pressure rising and droping rates ( + dp/dt) and their corrected values by LV systolic pressure ( + dp/dt/LVSP)were significantly reduced (all P ＜0.001 ), indicating LVRM occurred and LV systolic and diastolic function impaired after AMI. Compared with AMI group , LVEDP, LVV, LVAW and LVRW were all significantly decreased (P ＜0.05～0.001 ); while + dp/dt/LVSP were significantly enhanced in all 3 treatment groups (P ＜0.05～0.001 ) except -dp/dt/LVSP in losartan group (P＞ 0. 05 ). There were no significant differences in the above indices among the 3 treatment groups (all P＞ 0.05). Conclusion. Both losartan and enalapril can prevent from LVRM after AMI in the rat and improve LV function with equivalent effects. There seems no additive effect when the 2 drugs are used in combination.
文摘OBJECTIVE: To compare the effects of high, middle and low doses of enalapril in preventing left ventricular remodeling (LVRM) after acute myocardial infarction (AMI) in rats, especially evaluating the efficacy of low dose enalapril. METHODS: AMI was induced by ligating the left coronary artery in 149 female SD rats. 48 hours after the procedure, the 97 surviving rats were randomized to one of the following four groups: (1) AMI controls (n = 24), (2) high-dose (10 mg x kg(-1) x d(-1), n = 25), (3) middle-dose (1 mg x kg(-1) x d(-1), n = 23), and (4) low-dose (0.1 mg x kg(-1) x d(-1), n = 25) enalapril groups. In addition, sham-operated (n = 13) and normal rats (n = 10) were randomly selected to serve as non-infarction controls. Enalapril was delivered by direct gastric gavage. After 4 weeks of therapy, hemodynamic studies were performed, then the rat hearts were fixed with 10% formalin and pathology analysis was performed. Exclusive of the dead rats and those with MI size 55%, complete experimental data were obtained from 67 rats, which were comprised of (1) AMI controls (n = 13), (2) high-dose enalapril (n = 13), (3) middle-dose enalapril (n = 12), (4) low-dose enalapril (n = 12), (5) sham-operated (n = 8) and (6) normal (n = 9) groups. RESULTS: There were no significant differences among the four AMI groups in infarction size (all P > 0.05). Compared with the sham-operated group, the left ventricular (LV) end diastolic pressure (LVEDP), volume (LVV), absolute and relative weight (LVAW, LVRW) in AMI group were all significantly increased (all P
文摘Objective To explore the molecular mechanism underlying the decreased velocity of tension rise in rat myocardium during congestive heart failure (CHF) and left ventricular hypertrophy (LVH) induced by aortic stenosis.Methods The maximum velocity of tension rise (+dT/dtmax) was measured in left ventricular papillary muscle and the mRNA level of myosin heavy chain (MHC) isoforms in the left ventricle were detected by Northern blot analysis.Results The value of +dT/dtmax in CHF and LVH group were 64.17% and 37.15% lower than sham-operated controls (Sham) (P<0.01); values in the CHF group were 42.99% lower than that of LVH (P<0.01). The level of α-MHC mRNA in LVH was not different from that of the Sham (P>0.05), but decreased significantly in CHF to 42.3% of Sham and 56.1% of LVH (P<0.01). The level of β-MHC mRNA was up-regulated by 88.3% (P<0.01) in LVH compared with Sham and the level of β-MHC in CHF was 1.5-fold and 3.7-fold higher than that in LVH and Sham respectively (P<0.01). The ratio of α-MHC/β-MHC mRNA in LVH and CHF decreased to 42.4% and 9.8% respectively of the value in Sham (P<0.01). Correlation between α-MHC/β-MHC mRNA level and +dT/dtmax was analyzed which showed that these values were positively correlated with a correlation coefficient of 0.875 (P<0.01).Conclusion The decreased ratio of α-MHC/β-MHC mRNA was the major molecular mechanism underlying the decreased +dT/dtmax in CHF and LVH myocardium. The decreased ratio of α-MHC/β-MHC mRNA in LVH was mainly due to the up regulation of β-MHC mRNA while in CHF both down regulation of α-MHC and up regulation of β-MHC were involved.
文摘Objective To evaluate the immediate and follow-up results of percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy (HOCM). Methods Fifteen symptomatic, drug-refractory patients with HOCM underwent PTSMA procedures with application of a myocardial contrast echocardiography (MCE) intra-procedure. Before and after the procedure, clinical evaluations were obtained in all patients, who were followed up for a mean period of 8.6±3.8 (6-20) months.Results Immediate left ventricular outflow tract gradient (LVOTG) reduction was achieved (77.93±22?mm?Hg vs 14.8±15?mm?Hg, P【0.0001) after the procedure with a mean decrease of 5.75±2.87?mm?Hg of left ventricular end diastolic pressure (P【0.001). Follow up results revealed that ventricular remodelling occurred mainly 1-3 months after the procedure, but without evidence of ventricular dilation and contract dysfunction. Heart function (NYHA) was greatly improved (3.4±0.5 vs 1.1±0.4, P【0.001) and exercise endurance increased. A renewed increase of LVOTG was found in 2 patients during follow-up. Conclusions LVOTG was greatly decreased in HOCM patients undergoing a PTSMA procedure, and their symptoms were greatly improved without cardiac complications during follow-up. Sub-selection and re-opening of target vessels were the causes of renewed increase of LVOTG, and this can be avoided with the accumulation of experience. This is a promising method for the treatment of symptomatic patients with HOCM.
基金Natural Science and Technology Fund of Ningbo Science and Technology Bureau(Grant No.2017A610203)Yangtze River research project for sustainable development of hospitals in Zhejiang Province(Grant No.2020ZHA-YZJ102)。
文摘In the present study,we aimed to explore the protective effect of spironolactone on cardiac function in patients undergoing coronary stent implantation by determining the serum levels of GATA4 and hypoxia-inducible factor-1α(HIF-1α)proteins before and after the coronary stent implantation.A total of 134 patients undergoing coronary stent implantation in our hospital from March 2019 to March 2020 were retrospectively selected using the propensity score matching(PSM)method.Of the 134 patients,67 patients taking spironolactone were used as a test group,and the other 67 patients without taking spironolactone were used as a control group.In all patients,the levels of serum GATA4,HIF-1α,and troponin I proteins were determined before as well as 24 h and 6 months after the coronary stent implantation.Left ventricular ejection fraction(LVEF)and left ventricular systolic global longitudinal strain(GLS)were determined before and 6 months after the coronary stent implantation.There were no significant differences in the HIF-1αlevel between the two groups before and 6 months after the operation,while the HIF-1αlevel was significantly lower in the test group compared with the control group at 24 h after the operation(P<0.01).There were no significant differences in the GATA4 protein level between the two groups before and 24 h after the operation,while the GATA4 protein level was significantly lower in the test group compared with the control group at 6 months after the operation(P<0.01).There was no significant difference in LVEF between the two groups before and 6 months after the operation.GLS was significantly improved at 6 months after the operation compared with that before the operation in both groups,while GLS was significantly better in the test group compared with the control group at 6 months after the operation(P<0.01).Collectively,spironolactone could protect cardiac function probably by improving myocardial hypoxia and inhibiting myocardial remodeling.
