Objective To examine the clinical application of pulsed Doppler tissue imaging(DTI)for regional left ventricular function assessment in normal subjects. Methods We examined 50 healthy subjects(range 12-42 years,mean a...Objective To examine the clinical application of pulsed Doppler tissue imaging(DTI)for regional left ventricular function assessment in normal subjects. Methods We examined 50 healthy subjects(range 12-42 years,mean age 28.3 ± 6.9 years)using pulsed Doppler tissue imaging to characterize the diastolic and systolic velocity profiles of mitral annulus. Recordings were made along the long axis in the apical 4-chamber, 2-chamber, and long apical views of 6 sites(posterior-septum, lateral, anterior, inferior, anterior-septum, posterior)at the mitral annulus. Myocardial velocities were determined with use of variance F statistical analysis. Correlation analysis was employed to test the relationship between age and mitral annular velocities. Results Both early diastolic and systolic velocities at the septum were lower than other sites. There were no differences in mitral annulus late diastolic velocities. Mean early diastolic and systolic velocities was negatively correlated with age. Conclusions Doppler tissue imaging can directly reflect regional left ventricular function.展开更多
Background Heart failure(HF)is a leading cause of hospitalization and mortality for older chronic kidney disease(CKD)patients.However,the epidemiological data is scarce.We aimed to determine the prevalence of left ven...Background Heart failure(HF)is a leading cause of hospitalization and mortality for older chronic kidney disease(CKD)patients.However,the epidemiological data is scarce.We aimed to determine the prevalence of left ventricular(LV)dysfunction and HF,and to explore the risk factors for HF among those patients.Methods This is a cross-sectional analysis of the China Hypertension Survey conducted between October 2012 and December 2015.A total of 5,808 participants aged≥65 years were included in the analysis.Self-reported history of HF and any other cardiovascular diseases was acquired.2-D and Doppler echocardiography were used to assess LV dysfunction.CKD was defined as either estimated glomerular filtration rate(eGFR)<60 mL/min per 1.73 m2 or urinary albumin to creatinine ratio(ACR)≥30 mg/g.Results Among CKD patients aged≥65 years,the weighted prevalence of HF,heart failure with preserved ejection fraction(HFpEF),heart failure with mid-range ejection fraction(HFmrEF),and heart failure with reduced ejection fraction(HFrEF)was 4.8%,2.5%,0.8%,and 1.7%,respectively.The weighted prevalence of HF was 5.0%in patients with eGFR<60 mL/min per 1.73 m2,and was 5.9%in patients with ACR≥30 mg/g.The prevalence of LV systolic dysfunction was 3.1%,and while it was 8.9%for moderate/severe diastolic dysfunction.Multivariate analysis showed that smoking was significantly associated with the risk of HF.Furthermore,age,smoking,and residents in rural areas were significantly associated with a risk of LV diastolic dysfunction.Conclusions The prevalence of HF and LV dysfunction was high in older patients with CKD,suggesting that particular strategies will be required.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
Objective： To observe the effect of different combination antihypertensive therapies on plasma endothelin-1 （ET-1） concentration and left ventricular diastolic function of essential hypertension patients with left ...Objective： To observe the effect of different combination antihypertensive therapies on plasma endothelin-1 （ET-1） concentration and left ventricular diastolic function of essential hypertension patients with left ventricular hypertrophy （LVH） Methods： A total of 111 patients with essential hypertension were selected, including 60 cases （34 males, 26 females） aged （60.7±5.6） years with simple hypertension, and 51 cases （28 males, 23 females） aged （61.8±7.0） years with essential hypertension complicated with LVH. Essential hypertension patients with LVH were randomly divided into the group of amlodipine （2.5 mg/d） combined with telmisartan （40 mg/d, n=26） and the group of amlodipine （2.5 mg/d） combined with amiloride （half tablet/d, n=25）,and the treatment lasted for 1 year. Echocardiography was performed before and after the treatment. Left ventricular mass index （LVMI）, left ventricular isovolumic relaxation time （IVRT） and other indicators were detected, and plasma ET-1 concentrations were measured for comparative analysis. And 56 patients （31 males, 25 females） aged （59.3±6.7） years with normal blood pressure in the same period in our hospital were selected as the normal control group. Results： The general clinical characteristics were similar between hypertensive LVH group, simple hypertensive group and normal healthy control group. Plasma ET-1 concentrations, LVMI and IVRT of hypertensive LVH group were significantly higher than those of normal control group and simple hypertension group, and the difference was statistically significant. The patients＇ baseline blood pressure, ET-1, LVMI, interventricular septal thickness （IVST）, left ventricular posterior wall thickness （LVPWT）, left ventricular end-diastolic diameter （LVEDd） and other clinical parameters showed no significant difference （P〉0.05） between the group of amlodipine combined with telmisartan and the group of amlodipine combined with amiloride. It was found that compared with that before treatment, blood pressure could be effectively controlled （P〈0.05）, and LVMI, IVST, LVPWT and IVRT （P〈0.05） were all lowered, and ET-1 （P〈0.01） was significantly reduced after 1 year of antihypertensive therapy in both the group of amlodipine combined with telmisartan and the group of amlodipine combined with amiloride. The group of amlodipine combined with telmisartan was better in lowering blood pressure and reducing LVMI, IVST, LVPWT, IVRT and ET-1 than the group of amlodipine combined with amiloride （P〈0.05）. Conelus｜on： Amlodipine-based combination antthypertensive therapy could reverse LVH and improve left ventricular diastolic function partly by lowering blood pressure and ET-1, and the effect of amlodipine combined with telmisartan was superior to that ofamlodipine combined with amiloride展开更多
Objective To evaluate left atrial function in essential hypertension patients with different patterns of left ventricular geometric models by real-time three-dimensional echocardiography （RT-3DE） and left atrial tra...Objective To evaluate left atrial function in essential hypertension patients with different patterns of left ventricular geometric models by real-time three-dimensional echocardiography （RT-3DE） and left atrial tracking （EAT）.展开更多
BACKGROUND:Calcium calmodulin-dependent kinase II(CaMKII) can be more active in patients with left ventricular hypertrophy(LVH),which in turn causes phosphorylation of ryanodine receptors,resulting in inactivation and...BACKGROUND:Calcium calmodulin-dependent kinase II(CaMKII) can be more active in patients with left ventricular hypertrophy(LVH),which in turn causes phosphorylation of ryanodine receptors,resulting in inactivation and the instability of intracellular calcium homeostasis.The present study aimed to determine the effect of CaMKII-ryanodine receptor pathway signaling in rabbits with left ventricular hypertrophy and triggered ventricular arrhythmia.METHODS:Forty New Zealand rabbits were randomized into four groups(10 per group):sham group,LVH group,KN-93 group(LVH+KN-93),and ryanodine group(LVH+ryanodine).Rabbits in the LVH,KN-93,and ryanodine groups were used to establish a left ventricular hypertrophy model by the coarctation of the abdominal aorta,while those in the sham group did not undergo the coarctation.After eight weeks,action potentials(APs) were recorded simultaneously in the endocardium and epicardium,and a transmural electrocardiogram(ECG) was also recorded in the rabbit left ventricular wedge model.Drugs were administered to the animals in the KN-93 and ryanodine groups,and the frequency of triggered APs and ventricular tachycardia was recorded after the rabbits were given isoprenaline(1 μmol/L) and high-frequency stimulation.RESULTS:The frequency(animals/group) of triggered APs was 0/10 in the sham group,10/10 in the LVH group,4/10 in the KN-93 group,and 1/10 in the ryanodine group.The frequencies of ventricular tachycardia were 0/10,9/10,3/10,and 1/10,respectively.The frequencies of polymorphic ventricular tachycardia or ventricular fibrillation were 0/10,7/10,2/10,and 1/10,respectively.The frequencies of triggered ventricular arrhythmias in the KN-93 and ryanodine groups were much lower than those in the LVH group(P<0.05).CONCLUSIONS:KN-93 and ryanodine can effectively reduce the occurrence of triggered ventricular arrhythmia in rabbits with LVH.The CaMKII-ryanodine signaling pathway can be used as a new means of treating ventricular arrhythmia.展开更多
This work was to determine threshold values for accurate measurements of left ventricular end-diastolic volume(EDV),end-systolic volume(ESV),and ejection fraction(EF) from electrocardiography-gated myocardial perfusio...This work was to determine threshold values for accurate measurements of left ventricular end-diastolic volume(EDV),end-systolic volume(ESV),and ejection fraction(EF) from electrocardiography-gated myocardial perfusion imaging(MPI) in Chinese,and these data were compared with those of echocardiography.A total of 110 patients with definite or suspected coronary artery disease were referred for both gated MPI and echocardiography within 1 week.The EDV,ESV,and EF automatically measured by MyoMetrix and echocardiography were analyzed using Bland-Altman plot correlation and paired t test.The results showed that these parameters quantified by MyoMetrix software were correlated,moderately to highly,with those on echocardiography(ρ,r ≥0.75,P<0.01).However,the EF was not significantly correlated,with post-exercise MPI ESV of <15 mL or resting MPI ESV of <20 mL.At or above this ESV value,EF was underestimated by MyoMetrix(t≥ 4.60,P<0.01).In a word,a small ESV was underestimated by MyoMetrix,which could lead to EF overestimation.On the contrary,a normal or large ESV was overestimated by MyoMetrix,which led to EF underestimation.展开更多
Objective A novel index based on fi-equency-domain analysis of heart rate variability （HRV） was tested on patients with reduced left ventricular systolic function. This index, namely VHFI, was defined as the very hi...Objective A novel index based on fi-equency-domain analysis of heart rate variability （HRV） was tested on patients with reduced left ventricular systolic function. This index, namely VHFI, was defined as the very high frequency （VHF） component of the power spectrum normalized to represent its relative value in proportion to the total power minus the very low frequency component. Methods Patients （n = 130） were divided into a study group, consisting 66 patients with decreased left ventricular systolic function, and a control group, consisting 64 patients with normal heart structure and function and without severe coronary artery stenosis （〈 50%）. Results VHFI in the study group was significantly higher than that in the control group （19.17 ± 13.35 vs 11.37 ± 10.77, P 〈 0.001）. Cardiac events occurred in 18 patients during follow-up （33.34 i 3.26 months）. Defining the positive test as VHFI =15 and negative test as VHFI 〈15, achieved a sensitivity of 57.58% and a specificity of78.13% for predicting decreased left ventricular systolic function, and achieved a sensitivity of 66.67% and a specificity of 64.29% for predicting cardiac events. Univariate Cox regression analysis showed that positive VHFI test was an independent variable in predictive cardiac events. Conclusions The results suggest that VHFI is a useful tool for quick evaluation of left ventricular systolic function and prediction of prognosis展开更多
Objective： To compare function recovery of left ventricle after off-pump and on-pump coronary artery bypass （OPCAB and ONCAB） using Tel index. Methods： Twenty-four patients with coronary artery disease were enroll...Objective： To compare function recovery of left ventricle after off-pump and on-pump coronary artery bypass （OPCAB and ONCAB） using Tel index. Methods： Twenty-four patients with coronary artery disease were enrolled, twelve of which received OPCAB and the others underwent ONCAB. Left ventricular ejection fraction （LVEF）, E/A ratio at mitral orifice and Tel index were measured using transthoracic echocardiography before surgery and 3-7 days, 1 month, 3 months and 6 months after surgery. Results：Tel index of both groups decreased 3-7 days after surgery, with OPCAB group＇s lower than ONCAB group＇s. The difference between pre-and post-OPCAB was significant （P〈0.01）, but not for ONCAB group （P〈0.05）. Tel index of ONCAB decreased more significant than that of OPCAB 1 month after surgery, there was statistical difference between 3-7 days and 1 month after surgery in ONCAB （P〈0.01）. Afterwards, Tel index of the 2 groups decreased steadily with no significant difference between them at other time points. LVEF and E/A ratio decreased at first, then increased gradually, with no statistical differences between the 2 groups at all time points. Conclusion： The recovery of left ventricular function after OPCAB is earlier than ONCAB. Tel index is more sensitive than LVEF and E/A ratio in detecting cardiac function recoveries and can be considered as an accurate and simple method to evaluate left ventricular systolic and diastolic function.展开更多
Fifty-six patients with chest pain underwent selective coronaryangiography,radionuclide ventriculography (RNV) and frequency domaincardiography (FCG) to evaluate left ventricular function in coronary artery dis-ease (...Fifty-six patients with chest pain underwent selective coronaryangiography,radionuclide ventriculography (RNV) and frequency domaincardiography (FCG) to evaluate left ventricular function in coronary artery dis-ease (CAD).The sensitivity,specificity and accuracy of FCG were 87.5%,77.8%and 82.9%,respectively,which were slightly less than those of RNV (92.5%,88.9% and 90.8%,respectively).The changes of FCG scores were negatively corre-lated with changes of LVEF (r=-0.586,P【0.01),and TS (r=-0.679,P【0.01).These results indicate that FCG may be useful for the evaluation of leftventricular function in patients with CAD.展开更多
Background and Objective Diastolic dysfunction of the left ventricle is a mechanical abnormality diagnosed primarily by echocardiogram, and can be distinguished into three separate degrees based on the severity of red...Background and Objective Diastolic dysfunction of the left ventricle is a mechanical abnormality diagnosed primarily by echocardiogram, and can be distinguished into three separate degrees based on the severity of reduction in passive compliance and active myocardial relaxation. Methods A literature search was performed for basic science studies, clinical studies and major practice guidelines on the subject of diastolic dysfunction and diastolic heart failure. Important findings were analyzed and correlated with regard to clinical relevance. Results Left ventricular diastolic dysfunction appears to compromise exercise tolerance and is believed to contribute to the pathophysiology in patients with diastolic heart failure. In the clinical setting, however, oftentimes no clear distinction is made between echocardiographically diagnosed diastolic dysfunction and diastolic heart failure, and adequate treatment recommendations are sparse and aimed to prevent worsening and progression of clinical symptoms. To date, there is a lack of high powered trials assessing the possible progression rate from echocardiographically diagnosed diastolic dysfunction to the clinical diagnosis of diastolic heart failure. Furthermore, there are no solid indices to assess the degree of severity of diastolic dysfunction or its progression. Pure right ventricular diastolic dysfunction appears to be even less understood and under-recognized, although it may play a role in the development of both right and left heart failure. Currently there are few but interesting data on the possible interaction between ventricles with diastolic dysfunction and the overall affect on the development of heart failure. Conclusions The timeline and progression of diastolic dysfunction to diastolic heart failure have not been well established and warrant further investigation.展开更多
Objective: To observe the effect of carvedilol injection on left ventricular function and collagen remodeling in rat with myocardial infarction. Methods: Sixty rats with a model of myocardial infarction were randomly ...Objective: To observe the effect of carvedilol injection on left ventricular function and collagen remodeling in rat with myocardial infarction. Methods: Sixty rats with a model of myocardial infarction were randomly divided into nine groups. The rats of therapeutical group were treated with carvedilol injection (2 mg/d intraperitoneal injection) and/or captopil (2 g/L drinking water) . Acute myocardial infarction ( AMI) group did not receive drug treatment. The animals were sacrificed at 4 weeks and 8 weeks after coronary artery ligation. The levels of plasma angiotensin II and plasma aldosterone and left ventricle function were determined at different time. The collagen content and the ratio of type I and III collagen of noninfarcted area were also assessed. Results: Compared with AMI group, the levels of plasma and myocardium angiotensin II and plasma aldosterone in both carvedilol and captopil group decreased at the eighth week (P<0.05). In addition, carvedilol improved systolic and diastolic function (P<0. 05). Compared with sham group, both collagen content and the ratio of type I / III collagen of noninfarcted area increased in AMI4 and AMI8 group (P<0. 05). The hydroxyproline levels and the ratio of type I/III collagen significantly decreased after carvedilol and/or captopil treatment , compared with AMI group at 4 or 8 week (P <0. 05). Conclusion: Carvedilol can improve cardiac function after myocardial infarction and has beneficial effect on left ventricular remodeling.展开更多
Background Whether patients with reduced left ventricular function present worse outcome after transcatheter aortic valve implantation （TAVI） is controversial. The aim of this study was to assess the impact of basel...Background Whether patients with reduced left ventricular function present worse outcome after transcatheter aortic valve implantation （TAVI） is controversial. The aim of this study was to assess the impact of baseline severe impairment of left ventricular ejection fraction （LVEF） on mortality after TAVI. Methods Six-hundred-forty-nine patients with aortic stenosis underwent TAVI with the CoreValve system （92.8%） or the Edwards SAPIEN valve system （7.2%）. Baseline LVEF was measured by the echocardiographic Simpson method. The impact of LVEF 〈 30% on mortality was assessed by Cox regression. Results Patients with LVEF 〈 30% （n = 63）, as compared to those with LVEF 〉 30% （n = 586）, had a higher prevalence of NHYA class 〉 2 （P 〈 0.001） and presented with a higher Euroscore （P 〈 0.001）. Procedural success was similar in both groups （98.4% vs. 97.2%, P = 1）. After a median follow-up of 436 days （25^-75th percentile, 357-737 days）, all-cause mortality [23.8% vs. 23.7%, P = 0.87, hazard ratios （HR）： 0.96, 95% confidence intervals （CI）： 0.56-1.63] and cardiac mortality （19.1% vs. 17.6%, P = 0.89, HR： 1.04, 95% CI： 0.57-1.90） were similar in patients with LVEF 〈 30% as compared to those with LVEF 〉 30%. Thirty-day all-cause mortality was not significantly different between the two groups （11.1% vs. 6.3%, P = 0.14, HR： 1.81, 95% CI： 0.814.06）. Patients with LVEF 〈 30% had a trend toward higher risk of 30-day cardiac mortality （11.1% vs. 5.3%; P = 0.06, HR： 2.16, 95% CI： 0.95-4.90）, which disappeared after multivariable adjustment （P = 0.22）. Conclusions Baseline severe impairment of LVEF is not a predictor of increased short-term and mid-term mortality after TAVI. Selected patients with severe impairment of left ventricular function should not be denied TAVI.展开更多
Objective. To investigate the effect of left ventricular diastolic dysfunction on the pathogenesis of angina decubitus (AD). Methods. The study population consisted of three groups: 20 individuals without cardiovascul...Objective. To investigate the effect of left ventricular diastolic dysfunction on the pathogenesis of angina decubitus (AD). Methods. The study population consisted of three groups: 20 individuals without cardiovascular disease were studied as group Ⅰ.Group Ⅱ included 20 patents with coronary artery disease and without AD. Thirty-one patients with AD and ejection fraction(EF)>50% were studied as group Ⅲ. Group Ⅱ and Ⅲ were matched for age, EF and extent of coronary artery disease. Results. Left ventriculography (LVG) showed that left ventricular (LV) first 1/3 filling fraction(1/3FF) was significantly lower in group Ⅲ than in group Ⅱ and Ⅰ(both P<0001),but LV late 1/3 FF was much higher in group Ⅲ than in group Ⅱ and Ⅰ(P<005, P<001). Left ventricular end-diastolic pressure(LVEDP)was markedly increased before and after LVG in group Ⅱ and Ⅲ as compared with group Ⅰ (both P<005, both P<0001). The difference of LVEDP caused by left atrial contraction (left atrial contraction pressure difference, LACPD)before and after LVG was much higher in group Ⅲ than in group Ⅰ ( P<001, P<0001). Howevere,there were significant differences in LVEDP and in LACPD between before and after LVG only in group Ⅲ (both P<001). Conclusion. The patients with AD have LV diastolic dysfunction, which may be closely related to the pathogenesis of angina decubitus.展开更多
Congenital left ventricular aneurysm or diverticulum are rare cardiac malformations described in 809 cases since the first description in 1816, being associated with other cardiac, vascular or thoraco-abdominal abnorm...Congenital left ventricular aneurysm or diverticulum are rare cardiac malformations described in 809 cases since the first description in 1816, being associated with other cardiac, vascular or thoraco-abdominal abnormalities in about 70%. It appears to be a developmental anomaly, starting in the 4th embryonic week. In an experimental study, targeted knockdown of cardiac troponin T in the chick was performed at day 3, after the heart tube has formed. Morpholino treatment of gene TNNT2 at this stage led to the development of left ventricular diver- ticula （LVD） in the primitive left ventricular wall. Diagnosis of left ventricular aneurysms （LVA）/LVD can be made after exclusion of coro- nary artery disease, local or systemic inflammation or traumatic causes as well as cardiomyopathies. Clinically, most of LVA and LVD are asymptomatic or may cause systemic embolization, congestive heart failure, valvular regurgitation, ventricular wall rupture, ventricular tachycardia or sudden cardiac death. Diagnosis is established by imaging studies （echocardiography, magnetic resonance imaging or left ventricular angiography） visualizing the structural changes and accompanying abnormalities. Mode of treatment has to be individually tai- lored and depends on clinical presentation, accompanying abnormalities and possible complications, options include surgical resection （espe- cially in symptomatic patients）, anticoagulation after systemic embolization, radiofrequency ablation or implantation of an implantable car- dioverter defibrillator （ICD） in case of symptomatic ventricular tachycardias, and occasionally combined with class I- or III-antiarrhythmic drugs. Cardiac death occurs usually in childhood, is significantly more frequent in LVA patients and caused by congestive heart failure in most of the cases, whereas patients diagnosed with LVD died more frequently from rupture of the LVD.展开更多
Background Left ventricular(LV)remodeling is the most common target organ damage in hypertension.Previously,our study found that plasma microRNA-29a(miR-29a)level was associated with the LV remodeling in hypertensive ...Background Left ventricular(LV)remodeling is the most common target organ damage in hypertension.Previously,our study found that plasma microRNA-29a(miR-29a)level was associated with the LV remodeling in hypertensive patients.However,the causal relationship between miR-29a and LV remodeling remains unknown.Thus,the aim of this study was to investigate the regulation mechanism of miR-29a in LV remodeling.Methods&Results Overexpression and knockdown miR-29a mice were generated by tail-intravenous injection of miR-29a-mimic and inhibitor lentivirus for one week respectively.Then the mice were subjected to angiotensin-II(AngII)induced LV remodeling by subcutaneous AngII capsule osmotic pumping into AngII for four weeks.AngII-induced LV remodeling mice as the model group(n=9).Age-matched male SPF C57/BL6J mice(6–8 weeks old)were treated with the pumping of saline as a vehicle(n=6).In vivo,overexpression miR-29a ameliorated AngII-induced LV remodeling,while knockdown miR-29a deteriorated LV remodeling.Simultaneously,we observed that overexpression miR-29a mice inhibited but knockdown miR-29a mice increased cardiac cross-sectional area,indicating that miR-29a has an antagonistic effect on cardiac hypertrophy.Further studies found that overexpression miR-29a inhibited the content of the LV collagen including collagen I and III.Moreover,the expression of transforming growth factor-β(TGF-β)and phosphorylated SMAD2/3 decreased with the down-regulation of collagen I and III in overexpression miR-29a mice.Conclusions Our finding indicates that overexpression miR-29a attenuates LV remodeling by inhibiting collagen deposition,TGF-β,and phosphorylated SMAD2/3 expression.Thus,intervention miR-29a may be a therapeutic target for attenuating LV remodeling.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
To test the accuracy of real-time three-dimensional echocardiography (RT3DE) imaging system for evaluating left ventricular mass (LVM) in phantom and excised canine heart. Methods Ten left ventricular (LV) wall phanto...To test the accuracy of real-time three-dimensional echocardiography (RT3DE) imaging system for evaluating left ventricular mass (LVM) in phantom and excised canine heart. Methods Ten left ventricular (LV) wall phantoms made of two rubber-bursas, ten excised canine hearts underwent RT3DE and two-dimensional echocardiography (2DE). In RT3DE "full volume" imaging, the myocardial volume was mea-sured using 2,4,8, and 16-plane method with the analysis software of RT3DE. Mass was then calculated by multiplying the resulting myocardial volume by specific density of myocardial tissue. In 2DE the masses were measured by area-length meth-od. The true LV wall phantom mass was measured by water displacement and the canine LVM was weighed by anatomy, which served as a reference standard. We compared RT3DE or 2DE with true mass. Results In LV wall phantoms, RT3DE correlated with true masses strongly (r = 0.813-0.994) and weakly correlated between 2DE and true masses (r = 0.628). In excised canine hearts, there is an excellent correlation between RT3DE and true masses (r = 0.764-0.991), while 2DE value showed a lesser correlation (r = 0.514). There are no difference between RT-3DE and true masses (P > 0.05) but different between 2DE and true masses (P < 0.05). In different planes, there was no difference between 8-plane and 16-plane (P > 0.05) but different between 8-plane and 2, 4-plane (P < 0.05). Conclusion RT3DE can accurately quantify LVM and provide a new tool to evaluate LV function. For LVM by RT3DE, 8-plane measurement method is the best choice for accuracy and convenience.展开更多
1 Introduction? Mechanical circulatory support (MCS) has increasingly become an important management opportunity for patients with stage D heart failure (HF) with remarkable impact on patient survival and quality of l...1 Introduction? Mechanical circulatory support (MCS) has increasingly become an important management opportunity for patients with stage D heart failure (HF) with remarkable impact on patient survival and quality of life. Early clinical trials have demonstrated improved outcomes of durable left ventricular assist device (LVAD) support compared with optimal medical management.[1] As technology advanced, continuous flow LVADs outperformed pulsatile flow devices in clinical trials and the field migrated to HeartMate (Abbott Laboratories, Abbott Park, IL) and HeartWare (Medtronic, Minneapolis, MN) devices due to their clinical superiority. Among the continuous flow devices.展开更多
A 54-year-old female patient with congenital heart disease had a persistent complete left bundle branch block three months after closure by an Amplatzer ventricular septal defect occluder. Nine months later, the patie...A 54-year-old female patient with congenital heart disease had a persistent complete left bundle branch block three months after closure by an Amplatzer ventricular septal defect occluder. Nine months later, the patient suffered from chest distress, palpitation, and sweating at daily activities, and her 6-min walk distance decreased significantly （155 m）. Her echocardiography showed increased left ventricular end-diastolic diameter with left ventricular ejection fraction of 37%. Her symptoms reduced significantly one week after received cardiac resynchronization therapy. She had no symptoms at daily activities, and her echo showed left ventricular ejection fraction of 46%and 53%. Moreover, left ventricular end-diastolic diameter decreased 6 and 10 months after cardiac resynchronization therapy, and 6-min walk dis-tance remarkably increased. This case demonstrated that persistent complete left bundle branch block for nine months after transcatheter closure with ventricular septal defect Amplatzer occluder could lead to left ventricular enlargement and a significant decrease in left ventricular systolic function. Cardiac resynchronization therapy decreased left ventricular end-diastolic diameter and increased left ventricular ejection fraction, thereby improving the patient’s heart functions.展开更多
文摘Objective To examine the clinical application of pulsed Doppler tissue imaging(DTI)for regional left ventricular function assessment in normal subjects. Methods We examined 50 healthy subjects(range 12-42 years,mean age 28.3 ± 6.9 years)using pulsed Doppler tissue imaging to characterize the diastolic and systolic velocity profiles of mitral annulus. Recordings were made along the long axis in the apical 4-chamber, 2-chamber, and long apical views of 6 sites(posterior-septum, lateral, anterior, inferior, anterior-septum, posterior)at the mitral annulus. Myocardial velocities were determined with use of variance F statistical analysis. Correlation analysis was employed to test the relationship between age and mitral annular velocities. Results Both early diastolic and systolic velocities at the septum were lower than other sites. There were no differences in mitral annulus late diastolic velocities. Mean early diastolic and systolic velocities was negatively correlated with age. Conclusions Doppler tissue imaging can directly reflect regional left ventricular function.
基金the China National Science&Technology Pillar Program(2011BAI11B01)the National Health and Family Planning Commission,China(No.201402002)the CAMS Innovation Fund for Medical Sciences(2017-I2M-1-004)。
文摘Background Heart failure(HF)is a leading cause of hospitalization and mortality for older chronic kidney disease(CKD)patients.However,the epidemiological data is scarce.We aimed to determine the prevalence of left ventricular(LV)dysfunction and HF,and to explore the risk factors for HF among those patients.Methods This is a cross-sectional analysis of the China Hypertension Survey conducted between October 2012 and December 2015.A total of 5,808 participants aged≥65 years were included in the analysis.Self-reported history of HF and any other cardiovascular diseases was acquired.2-D and Doppler echocardiography were used to assess LV dysfunction.CKD was defined as either estimated glomerular filtration rate(eGFR)<60 mL/min per 1.73 m2 or urinary albumin to creatinine ratio(ACR)≥30 mg/g.Results Among CKD patients aged≥65 years,the weighted prevalence of HF,heart failure with preserved ejection fraction(HFpEF),heart failure with mid-range ejection fraction(HFmrEF),and heart failure with reduced ejection fraction(HFrEF)was 4.8%,2.5%,0.8%,and 1.7%,respectively.The weighted prevalence of HF was 5.0%in patients with eGFR<60 mL/min per 1.73 m2,and was 5.9%in patients with ACR≥30 mg/g.The prevalence of LV systolic dysfunction was 3.1%,and while it was 8.9%for moderate/severe diastolic dysfunction.Multivariate analysis showed that smoking was significantly associated with the risk of HF.Furthermore,age,smoking,and residents in rural areas were significantly associated with a risk of LV diastolic dysfunction.Conclusions The prevalence of HF and LV dysfunction was high in older patients with CKD,suggesting that particular strategies will be required.
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.
基金Supported by the National Natural and Science Foundation of China(30871042)
文摘Objective： To observe the effect of different combination antihypertensive therapies on plasma endothelin-1 （ET-1） concentration and left ventricular diastolic function of essential hypertension patients with left ventricular hypertrophy （LVH） Methods： A total of 111 patients with essential hypertension were selected, including 60 cases （34 males, 26 females） aged （60.7±5.6） years with simple hypertension, and 51 cases （28 males, 23 females） aged （61.8±7.0） years with essential hypertension complicated with LVH. Essential hypertension patients with LVH were randomly divided into the group of amlodipine （2.5 mg/d） combined with telmisartan （40 mg/d, n=26） and the group of amlodipine （2.5 mg/d） combined with amiloride （half tablet/d, n=25）,and the treatment lasted for 1 year. Echocardiography was performed before and after the treatment. Left ventricular mass index （LVMI）, left ventricular isovolumic relaxation time （IVRT） and other indicators were detected, and plasma ET-1 concentrations were measured for comparative analysis. And 56 patients （31 males, 25 females） aged （59.3±6.7） years with normal blood pressure in the same period in our hospital were selected as the normal control group. Results： The general clinical characteristics were similar between hypertensive LVH group, simple hypertensive group and normal healthy control group. Plasma ET-1 concentrations, LVMI and IVRT of hypertensive LVH group were significantly higher than those of normal control group and simple hypertension group, and the difference was statistically significant. The patients＇ baseline blood pressure, ET-1, LVMI, interventricular septal thickness （IVST）, left ventricular posterior wall thickness （LVPWT）, left ventricular end-diastolic diameter （LVEDd） and other clinical parameters showed no significant difference （P〉0.05） between the group of amlodipine combined with telmisartan and the group of amlodipine combined with amiloride. It was found that compared with that before treatment, blood pressure could be effectively controlled （P〈0.05）, and LVMI, IVST, LVPWT and IVRT （P〈0.05） were all lowered, and ET-1 （P〈0.01） was significantly reduced after 1 year of antihypertensive therapy in both the group of amlodipine combined with telmisartan and the group of amlodipine combined with amiloride. The group of amlodipine combined with telmisartan was better in lowering blood pressure and reducing LVMI, IVST, LVPWT, IVRT and ET-1 than the group of amlodipine combined with amiloride （P〈0.05）. Conelus｜on： Amlodipine-based combination antthypertensive therapy could reverse LVH and improve left ventricular diastolic function partly by lowering blood pressure and ET-1, and the effect of amlodipine combined with telmisartan was superior to that ofamlodipine combined with amiloride
基金Supported by the Natural Science Foundation of Liaoning ProvinceChina(2013023010)
文摘Objective To evaluate left atrial function in essential hypertension patients with different patterns of left ventricular geometric models by real-time three-dimensional echocardiography （RT-3DE） and left atrial tracking （EAT）.
基金supported by a grant from Surface Project of Natural Science Foundation of Fujian Province(2008J0075)
文摘BACKGROUND:Calcium calmodulin-dependent kinase II(CaMKII) can be more active in patients with left ventricular hypertrophy(LVH),which in turn causes phosphorylation of ryanodine receptors,resulting in inactivation and the instability of intracellular calcium homeostasis.The present study aimed to determine the effect of CaMKII-ryanodine receptor pathway signaling in rabbits with left ventricular hypertrophy and triggered ventricular arrhythmia.METHODS:Forty New Zealand rabbits were randomized into four groups(10 per group):sham group,LVH group,KN-93 group(LVH+KN-93),and ryanodine group(LVH+ryanodine).Rabbits in the LVH,KN-93,and ryanodine groups were used to establish a left ventricular hypertrophy model by the coarctation of the abdominal aorta,while those in the sham group did not undergo the coarctation.After eight weeks,action potentials(APs) were recorded simultaneously in the endocardium and epicardium,and a transmural electrocardiogram(ECG) was also recorded in the rabbit left ventricular wedge model.Drugs were administered to the animals in the KN-93 and ryanodine groups,and the frequency of triggered APs and ventricular tachycardia was recorded after the rabbits were given isoprenaline(1 μmol/L) and high-frequency stimulation.RESULTS:The frequency(animals/group) of triggered APs was 0/10 in the sham group,10/10 in the LVH group,4/10 in the KN-93 group,and 1/10 in the ryanodine group.The frequencies of ventricular tachycardia were 0/10,9/10,3/10,and 1/10,respectively.The frequencies of polymorphic ventricular tachycardia or ventricular fibrillation were 0/10,7/10,2/10,and 1/10,respectively.The frequencies of triggered ventricular arrhythmias in the KN-93 and ryanodine groups were much lower than those in the LVH group(P<0.05).CONCLUSIONS:KN-93 and ryanodine can effectively reduce the occurrence of triggered ventricular arrhythmia in rabbits with LVH.The CaMKII-ryanodine signaling pathway can be used as a new means of treating ventricular arrhythmia.
基金supported by the Natural Science Foundation of Fujian Province(No.2015J01516)
文摘This work was to determine threshold values for accurate measurements of left ventricular end-diastolic volume(EDV),end-systolic volume(ESV),and ejection fraction(EF) from electrocardiography-gated myocardial perfusion imaging(MPI) in Chinese,and these data were compared with those of echocardiography.A total of 110 patients with definite or suspected coronary artery disease were referred for both gated MPI and echocardiography within 1 week.The EDV,ESV,and EF automatically measured by MyoMetrix and echocardiography were analyzed using Bland-Altman plot correlation and paired t test.The results showed that these parameters quantified by MyoMetrix software were correlated,moderately to highly,with those on echocardiography(ρ,r ≥0.75,P<0.01).However,the EF was not significantly correlated,with post-exercise MPI ESV of <15 mL or resting MPI ESV of <20 mL.At or above this ESV value,EF was underestimated by MyoMetrix(t≥ 4.60,P<0.01).In a word,a small ESV was underestimated by MyoMetrix,which could lead to EF overestimation.On the contrary,a normal or large ESV was overestimated by MyoMetrix,which led to EF underestimation.
文摘Objective A novel index based on fi-equency-domain analysis of heart rate variability （HRV） was tested on patients with reduced left ventricular systolic function. This index, namely VHFI, was defined as the very high frequency （VHF） component of the power spectrum normalized to represent its relative value in proportion to the total power minus the very low frequency component. Methods Patients （n = 130） were divided into a study group, consisting 66 patients with decreased left ventricular systolic function, and a control group, consisting 64 patients with normal heart structure and function and without severe coronary artery stenosis （〈 50%）. Results VHFI in the study group was significantly higher than that in the control group （19.17 ± 13.35 vs 11.37 ± 10.77, P 〈 0.001）. Cardiac events occurred in 18 patients during follow-up （33.34 i 3.26 months）. Defining the positive test as VHFI =15 and negative test as VHFI 〈15, achieved a sensitivity of 57.58% and a specificity of78.13% for predicting decreased left ventricular systolic function, and achieved a sensitivity of 66.67% and a specificity of 64.29% for predicting cardiac events. Univariate Cox regression analysis showed that positive VHFI test was an independent variable in predictive cardiac events. Conclusions The results suggest that VHFI is a useful tool for quick evaluation of left ventricular systolic function and prediction of prognosis
基金Supported by Scientific Technology development Foundation of Shanghai(024119028)
文摘Objective： To compare function recovery of left ventricle after off-pump and on-pump coronary artery bypass （OPCAB and ONCAB） using Tel index. Methods： Twenty-four patients with coronary artery disease were enrolled, twelve of which received OPCAB and the others underwent ONCAB. Left ventricular ejection fraction （LVEF）, E/A ratio at mitral orifice and Tel index were measured using transthoracic echocardiography before surgery and 3-7 days, 1 month, 3 months and 6 months after surgery. Results：Tel index of both groups decreased 3-7 days after surgery, with OPCAB group＇s lower than ONCAB group＇s. The difference between pre-and post-OPCAB was significant （P〈0.01）, but not for ONCAB group （P〈0.05）. Tel index of ONCAB decreased more significant than that of OPCAB 1 month after surgery, there was statistical difference between 3-7 days and 1 month after surgery in ONCAB （P〈0.01）. Afterwards, Tel index of the 2 groups decreased steadily with no significant difference between them at other time points. LVEF and E/A ratio decreased at first, then increased gradually, with no statistical differences between the 2 groups at all time points. Conclusion： The recovery of left ventricular function after OPCAB is earlier than ONCAB. Tel index is more sensitive than LVEF and E/A ratio in detecting cardiac function recoveries and can be considered as an accurate and simple method to evaluate left ventricular systolic and diastolic function.
文摘Fifty-six patients with chest pain underwent selective coronaryangiography,radionuclide ventriculography (RNV) and frequency domaincardiography (FCG) to evaluate left ventricular function in coronary artery dis-ease (CAD).The sensitivity,specificity and accuracy of FCG were 87.5%,77.8%and 82.9%,respectively,which were slightly less than those of RNV (92.5%,88.9% and 90.8%,respectively).The changes of FCG scores were negatively corre-lated with changes of LVEF (r=-0.586,P【0.01),and TS (r=-0.679,P【0.01).These results indicate that FCG may be useful for the evaluation of leftventricular function in patients with CAD.
文摘Background and Objective Diastolic dysfunction of the left ventricle is a mechanical abnormality diagnosed primarily by echocardiogram, and can be distinguished into three separate degrees based on the severity of reduction in passive compliance and active myocardial relaxation. Methods A literature search was performed for basic science studies, clinical studies and major practice guidelines on the subject of diastolic dysfunction and diastolic heart failure. Important findings were analyzed and correlated with regard to clinical relevance. Results Left ventricular diastolic dysfunction appears to compromise exercise tolerance and is believed to contribute to the pathophysiology in patients with diastolic heart failure. In the clinical setting, however, oftentimes no clear distinction is made between echocardiographically diagnosed diastolic dysfunction and diastolic heart failure, and adequate treatment recommendations are sparse and aimed to prevent worsening and progression of clinical symptoms. To date, there is a lack of high powered trials assessing the possible progression rate from echocardiographically diagnosed diastolic dysfunction to the clinical diagnosis of diastolic heart failure. Furthermore, there are no solid indices to assess the degree of severity of diastolic dysfunction or its progression. Pure right ventricular diastolic dysfunction appears to be even less understood and under-recognized, although it may play a role in the development of both right and left heart failure. Currently there are few but interesting data on the possible interaction between ventricles with diastolic dysfunction and the overall affect on the development of heart failure. Conclusions The timeline and progression of diastolic dysfunction to diastolic heart failure have not been well established and warrant further investigation.
文摘Objective: To observe the effect of carvedilol injection on left ventricular function and collagen remodeling in rat with myocardial infarction. Methods: Sixty rats with a model of myocardial infarction were randomly divided into nine groups. The rats of therapeutical group were treated with carvedilol injection (2 mg/d intraperitoneal injection) and/or captopil (2 g/L drinking water) . Acute myocardial infarction ( AMI) group did not receive drug treatment. The animals were sacrificed at 4 weeks and 8 weeks after coronary artery ligation. The levels of plasma angiotensin II and plasma aldosterone and left ventricle function were determined at different time. The collagen content and the ratio of type I and III collagen of noninfarcted area were also assessed. Results: Compared with AMI group, the levels of plasma and myocardium angiotensin II and plasma aldosterone in both carvedilol and captopil group decreased at the eighth week (P<0.05). In addition, carvedilol improved systolic and diastolic function (P<0. 05). Compared with sham group, both collagen content and the ratio of type I / III collagen of noninfarcted area increased in AMI4 and AMI8 group (P<0. 05). The hydroxyproline levels and the ratio of type I/III collagen significantly decreased after carvedilol and/or captopil treatment , compared with AMI group at 4 or 8 week (P <0. 05). Conclusion: Carvedilol can improve cardiac function after myocardial infarction and has beneficial effect on left ventricular remodeling.
文摘Background Whether patients with reduced left ventricular function present worse outcome after transcatheter aortic valve implantation （TAVI） is controversial. The aim of this study was to assess the impact of baseline severe impairment of left ventricular ejection fraction （LVEF） on mortality after TAVI. Methods Six-hundred-forty-nine patients with aortic stenosis underwent TAVI with the CoreValve system （92.8%） or the Edwards SAPIEN valve system （7.2%）. Baseline LVEF was measured by the echocardiographic Simpson method. The impact of LVEF 〈 30% on mortality was assessed by Cox regression. Results Patients with LVEF 〈 30% （n = 63）, as compared to those with LVEF 〉 30% （n = 586）, had a higher prevalence of NHYA class 〉 2 （P 〈 0.001） and presented with a higher Euroscore （P 〈 0.001）. Procedural success was similar in both groups （98.4% vs. 97.2%, P = 1）. After a median follow-up of 436 days （25^-75th percentile, 357-737 days）, all-cause mortality [23.8% vs. 23.7%, P = 0.87, hazard ratios （HR）： 0.96, 95% confidence intervals （CI）： 0.56-1.63] and cardiac mortality （19.1% vs. 17.6%, P = 0.89, HR： 1.04, 95% CI： 0.57-1.90） were similar in patients with LVEF 〈 30% as compared to those with LVEF 〉 30%. Thirty-day all-cause mortality was not significantly different between the two groups （11.1% vs. 6.3%, P = 0.14, HR： 1.81, 95% CI： 0.814.06）. Patients with LVEF 〈 30% had a trend toward higher risk of 30-day cardiac mortality （11.1% vs. 5.3%; P = 0.06, HR： 2.16, 95% CI： 0.95-4.90）, which disappeared after multivariable adjustment （P = 0.22）. Conclusions Baseline severe impairment of LVEF is not a predictor of increased short-term and mid-term mortality after TAVI. Selected patients with severe impairment of left ventricular function should not be denied TAVI.
文摘Objective. To investigate the effect of left ventricular diastolic dysfunction on the pathogenesis of angina decubitus (AD). Methods. The study population consisted of three groups: 20 individuals without cardiovascular disease were studied as group Ⅰ.Group Ⅱ included 20 patents with coronary artery disease and without AD. Thirty-one patients with AD and ejection fraction(EF)>50% were studied as group Ⅲ. Group Ⅱ and Ⅲ were matched for age, EF and extent of coronary artery disease. Results. Left ventriculography (LVG) showed that left ventricular (LV) first 1/3 filling fraction(1/3FF) was significantly lower in group Ⅲ than in group Ⅱ and Ⅰ(both P<0001),but LV late 1/3 FF was much higher in group Ⅲ than in group Ⅱ and Ⅰ(P<005, P<001). Left ventricular end-diastolic pressure(LVEDP)was markedly increased before and after LVG in group Ⅱ and Ⅲ as compared with group Ⅰ (both P<005, both P<0001). The difference of LVEDP caused by left atrial contraction (left atrial contraction pressure difference, LACPD)before and after LVG was much higher in group Ⅲ than in group Ⅰ ( P<001, P<0001). Howevere,there were significant differences in LVEDP and in LACPD between before and after LVG only in group Ⅲ (both P<001). Conclusion. The patients with AD have LV diastolic dysfunction, which may be closely related to the pathogenesis of angina decubitus.
文摘Congenital left ventricular aneurysm or diverticulum are rare cardiac malformations described in 809 cases since the first description in 1816, being associated with other cardiac, vascular or thoraco-abdominal abnormalities in about 70%. It appears to be a developmental anomaly, starting in the 4th embryonic week. In an experimental study, targeted knockdown of cardiac troponin T in the chick was performed at day 3, after the heart tube has formed. Morpholino treatment of gene TNNT2 at this stage led to the development of left ventricular diver- ticula （LVD） in the primitive left ventricular wall. Diagnosis of left ventricular aneurysms （LVA）/LVD can be made after exclusion of coro- nary artery disease, local or systemic inflammation or traumatic causes as well as cardiomyopathies. Clinically, most of LVA and LVD are asymptomatic or may cause systemic embolization, congestive heart failure, valvular regurgitation, ventricular wall rupture, ventricular tachycardia or sudden cardiac death. Diagnosis is established by imaging studies （echocardiography, magnetic resonance imaging or left ventricular angiography） visualizing the structural changes and accompanying abnormalities. Mode of treatment has to be individually tai- lored and depends on clinical presentation, accompanying abnormalities and possible complications, options include surgical resection （espe- cially in symptomatic patients）, anticoagulation after systemic embolization, radiofrequency ablation or implantation of an implantable car- dioverter defibrillator （ICD） in case of symptomatic ventricular tachycardias, and occasionally combined with class I- or III-antiarrhythmic drugs. Cardiac death occurs usually in childhood, is significantly more frequent in LVA patients and caused by congestive heart failure in most of the cases, whereas patients diagnosed with LVD died more frequently from rupture of the LVD.
基金supported by the National Natural Science Foundation of China(No.81570383)
文摘Background Left ventricular(LV)remodeling is the most common target organ damage in hypertension.Previously,our study found that plasma microRNA-29a(miR-29a)level was associated with the LV remodeling in hypertensive patients.However,the causal relationship between miR-29a and LV remodeling remains unknown.Thus,the aim of this study was to investigate the regulation mechanism of miR-29a in LV remodeling.Methods&Results Overexpression and knockdown miR-29a mice were generated by tail-intravenous injection of miR-29a-mimic and inhibitor lentivirus for one week respectively.Then the mice were subjected to angiotensin-II(AngII)induced LV remodeling by subcutaneous AngII capsule osmotic pumping into AngII for four weeks.AngII-induced LV remodeling mice as the model group(n=9).Age-matched male SPF C57/BL6J mice(6–8 weeks old)were treated with the pumping of saline as a vehicle(n=6).In vivo,overexpression miR-29a ameliorated AngII-induced LV remodeling,while knockdown miR-29a deteriorated LV remodeling.Simultaneously,we observed that overexpression miR-29a mice inhibited but knockdown miR-29a mice increased cardiac cross-sectional area,indicating that miR-29a has an antagonistic effect on cardiac hypertrophy.Further studies found that overexpression miR-29a inhibited the content of the LV collagen including collagen I and III.Moreover,the expression of transforming growth factor-β(TGF-β)and phosphorylated SMAD2/3 decreased with the down-regulation of collagen I and III in overexpression miR-29a mice.Conclusions Our finding indicates that overexpression miR-29a attenuates LV remodeling by inhibiting collagen deposition,TGF-β,and phosphorylated SMAD2/3 expression.Thus,intervention miR-29a may be a therapeutic target for attenuating LV remodeling.
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To test the accuracy of real-time three-dimensional echocardiography (RT3DE) imaging system for evaluating left ventricular mass (LVM) in phantom and excised canine heart. Methods Ten left ventricular (LV) wall phantoms made of two rubber-bursas, ten excised canine hearts underwent RT3DE and two-dimensional echocardiography (2DE). In RT3DE "full volume" imaging, the myocardial volume was mea-sured using 2,4,8, and 16-plane method with the analysis software of RT3DE. Mass was then calculated by multiplying the resulting myocardial volume by specific density of myocardial tissue. In 2DE the masses were measured by area-length meth-od. The true LV wall phantom mass was measured by water displacement and the canine LVM was weighed by anatomy, which served as a reference standard. We compared RT3DE or 2DE with true mass. Results In LV wall phantoms, RT3DE correlated with true masses strongly (r = 0.813-0.994) and weakly correlated between 2DE and true masses (r = 0.628). In excised canine hearts, there is an excellent correlation between RT3DE and true masses (r = 0.764-0.991), while 2DE value showed a lesser correlation (r = 0.514). There are no difference between RT-3DE and true masses (P > 0.05) but different between 2DE and true masses (P < 0.05). In different planes, there was no difference between 8-plane and 16-plane (P > 0.05) but different between 8-plane and 2, 4-plane (P < 0.05). Conclusion RT3DE can accurately quantify LVM and provide a new tool to evaluate LV function. For LVM by RT3DE, 8-plane measurement method is the best choice for accuracy and convenience.
文摘1 Introduction? Mechanical circulatory support (MCS) has increasingly become an important management opportunity for patients with stage D heart failure (HF) with remarkable impact on patient survival and quality of life. Early clinical trials have demonstrated improved outcomes of durable left ventricular assist device (LVAD) support compared with optimal medical management.[1] As technology advanced, continuous flow LVADs outperformed pulsatile flow devices in clinical trials and the field migrated to HeartMate (Abbott Laboratories, Abbott Park, IL) and HeartWare (Medtronic, Minneapolis, MN) devices due to their clinical superiority. Among the continuous flow devices.
文摘A 54-year-old female patient with congenital heart disease had a persistent complete left bundle branch block three months after closure by an Amplatzer ventricular septal defect occluder. Nine months later, the patient suffered from chest distress, palpitation, and sweating at daily activities, and her 6-min walk distance decreased significantly （155 m）. Her echocardiography showed increased left ventricular end-diastolic diameter with left ventricular ejection fraction of 37%. Her symptoms reduced significantly one week after received cardiac resynchronization therapy. She had no symptoms at daily activities, and her echo showed left ventricular ejection fraction of 46%and 53%. Moreover, left ventricular end-diastolic diameter decreased 6 and 10 months after cardiac resynchronization therapy, and 6-min walk dis-tance remarkably increased. This case demonstrated that persistent complete left bundle branch block for nine months after transcatheter closure with ventricular septal defect Amplatzer occluder could lead to left ventricular enlargement and a significant decrease in left ventricular systolic function. Cardiac resynchronization therapy decreased left ventricular end-diastolic diameter and increased left ventricular ejection fraction, thereby improving the patient’s heart functions.
