Left bundle branch pacing vs biventricular pacing in heart failure patients with left bundle branch block:A systematic review and meta-analysis

BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore the validity of electromechanical resynchronization,clinical and echocardiographic response of LBBP-CRT.METHODS Systematic review and Meta-analysis were conducted in accordance with the standard guidelines as mentioned in detail in the methodology section.RESULTS In our analysis,the success rate of LBBP-CRT was determined to be 91.1%.LBBP CRT significantly shortened QRS duration,with significant improvement in echocardiographic parameters,including left ventricular ejection fraction,left ventricular end-diastolic diameter and left ventricular end-systolic diameter in comparison with BiVP-CRT.CONCLUSION A significant reduction in New York Heart Association class and B-type natriuretic peptide levels was also observed in the LBBP-CRT group vs BiVP-CRT group.Lastly,the LBBP-CRT cohort had a reduced pacing threshold at follow-up as compared to BiVP-CRT.

Impact of single chamber and dual chamber permanent pacemaker implantation on left ventricular function:An observational study

BACKGROUND Permanent pacemaker implantation has the potential to impact left ventricular(LV)function and hence quality of life(QoL)in the long term.AIM To assess the effect of single-and dual-chamber pacing on LV function and QoL.METHODS This study included 56 patients who underwent permanent pacing:Dual pacing,dual sensing,dual responsive and rate responsive(DDDR)for the initial 3 months,ventricular sensing,inhibited response and rate responsive(VVIR)for the next 3 months,and DDDR mode for the last 3 months.Throughout the study period,various echocardiographic parameters,functional status,and QoL were measured to assess the impact of pacing on LV function compared with baseline and at every 3 months interval.RESULTS A significant change appeared in cardiac function after VVIR pacing which was in diastolic properties of LV as shown by increase in isovolumic relaxation time from(85.28±9.54 ms)to(89.53±9.65 ms).At the 3-,6-,and 9-month follow-up,reduction in LV ejection fraction was observed to be 62.71±4.66%,61.07±4.41%,and 58.48±3.89%,respectively.An increase in the QoL scores was noted at every follow-up visit.CONCLUSION An apparent depressant effect on LV function due to right ventricular pacing,with a higher incidence of adverse outcomes in the VVIR mode.In addition,an upsurge in QoL scores for the study population was noted,which indicates improvement in the QoL of patients post-pacing,irrespective of the mode.Generally,the DDDR mode is a highly preferable pacing mode.

Effect of Salvia Miltiorrhiza Bge on Left Ventricular Hypertrophy and the Expression of Tumor Necrosis Factor-α in Spontaneously Hypertensive Rats

The effects of salvia miltiorrhiza Bge (SMB) on left ventricular hypertrophy (LVH) and the expression of tumor necrosis factor-α (TNF-α) in the left ventricle of spontaneously hypertensive rats and the action mechanism were investigated. Normal Wistar-kyoto (WKY) rats were used as negative control, and spontaneously hypertensive rats (SHR) were randomly assigned to receive pla- cebo or SMB. SMB (1 g/kg·d) was injected intraperitoneally for 12 weeks. Systolic blood pressure (SBP) and left ventricular mass index (LVMI) were measured. HE, VG and immunohistochemical staining combined with computed morphometry were employed to evaluate the cardiomyocyte size, diameter, the collagen volume fraction (CVF), perivascular circumferential area (PVCA), and tumor necrosis factor-α (TNF-α) expression in the left ventricular tissue. The results showed, as compared with WKY rats, the SBP, LVMI, cardiomyocyte size, diameter, CVF, PCVA, and TNF-α expression were increased markedly in the 20-week-old spontaneously hypertensive rats. SMB decreased LVMI (P<0.01), size of cardiomyocytes (P<0.01), collagen volume fraction (P<0.01), perivascular circum- ferential area (P<0.01), and TNF-α expression (P<0.01), but had no effect on SBP (P>0.05). It was suggested that chronic administration of SMB could inhibit and reverse the development of LVH in spontaneously hypertensive rats independent of BP. TNF-α may be involved in the reversal mecha- nism of LVH by SMB.

Deep learning echocardiographic intelligent model for evaluation on left ventricular regional wall motion abnormality

Objective To observe the value of deep learning echocardiographic intelligent model for evaluation on left ventricular(LV)regional wall motion abnormalities(RWMA).Methods Apical two-chamber,three-chamber and four-chamber views two-dimensional echocardiograms were obtained prospectively in 205 patients with coronary heart disease.The model for evaluating LV regional contractile function was constructed using a five-fold cross-validation method to automatically identify the presence of RWMA or not,and the performance of this model was assessed taken manual interpretation of RWMA as standards.Results Among 205 patients,RWMA was detected in totally 650 segments in 83 cases.LV myocardial segmentation model demonstrated good efficacy for delineation of LV myocardium.The average Dice similarity coefficient for LV myocardial segmentation results in the apical two-chamber,three-chamber and four-chamber views was 0.85,0.82 and 0.88,respectively.LV myocardial segmentation model accurately segmented LV myocardium in apical two-chamber,three-chamber and four-chamber views.The mean area under the curve(AUC)of RWMA identification model was 0.843±0.071,with sensitivity of(64.19±14.85)%,specificity of(89.44±7.31)%and accuracy of(85.22±4.37)%.Conclusion Deep learning echocardiographic intelligent model could be used to automatically evaluate LV regional contractile function,hence rapidly and accurately identifying RWMA.

Individualized anti-thrombotic therapy for acute myocardial infarction complicated with left ventricular thrombus: A case report

BACKGROUND Presently,there is no established standard anti-blood clot therapy for patients facing acute myocardial infarction(AMI)complicated by left ventricular thrombus(LVT).While vitamin K antagonists are the preferred choice for oral blood thinning,determining the best course of blood-thinning medication remains challenging.It is unclear if non-vitamin K antagonist oral blood thinners have different effectiveness in treating LVT.This study significantly contributes to the medical community.CASE SUMMARY The blood-thinning treatment of a patient with AMI and LVT was analyzed.Triple blood-thinning therapy included daily enteric-coated aspirin tablets at 0.1 g,daily clopidogrel hydrogen sulfate at 75 mg,and dabigatran etexilate at 110 mg twice daily.After 15 d,the patient’s LVT did not decrease but instead increased.Clinical pharmacists comprehensively analyzed the cases from the perspective of the patient’s disease status and drug interaction.The drug regimen was reformulated for the patient,replacing dabigatran etexilate with warfarin,and was administered for six months.The clinical pharmacist provided the patient with professional and standardized pharmaceutical services.The patient’s condition was discharged after meeting the international normalized ratio value(2-3)criteria.The patient fully complied with the follow-up,and the time in the therapeutic range was 78.57%,with no serious adverse effects during pharmaceutical monitoring.CONCLUSION Warfarin proves to be an effective drug for patients with AMI complicated by LVT,and its blood-thinning course lasts for six months.

Left ventricular thrombosis caused cerebral embolism during venoarterial extracorporeal membrane oxygenation support: A case report

BACKGROUND Venoarterial(VA)extracorporeal membrane oxygenation(ECMO),an effective short-term circulatory support method for refractory cardiogenic shock,is widely applied.However,retrospective analyses have shown that VA-ECMO-assisted cases were associated with a relatively high mortality rate of approximately 60%.Embolization in important organs caused by complications of left ventricular thrombosis(LVT)during VA-ECMO is also an important reason.Although the incidence of LVT during VA-ECMO is not high,the consequences of embolization are disastrous.CASE SUMMARY A 37-year-old female patient was admitted to hospital because of fever for 4 d and palpitations for 3 d.After excluding the diagnosis of coronary heart disease,we established a diagnosis of“clinically explosive myocarditis”.The patient still had unstable hemodynamics after drug treatment supported by VA-ECMO,with heparin for anticoagulation.On day 4 of ECMO support,a left ventricular thro-mbus attached to the papillary muscle root of the mitral valve was found by transthoracic echocardiography.Left ventricular decompression was performed and ECMO was successfully removed,but the patient eventually died of multiple cerebral embolism.CONCLUSION LVT with high mobility during VA-ECMO may cause embolism in important organs.Therefore,a"wait and see"strategy should be avoided.

Application of three-dimensional speckle tracking technique in measuring left ventricular myocardial function in patients with diabetes

BACKGROUND Diabetic cardiomyopathy is considered as a chronic complication of diabetes mellitus(DM).Therefore,early detection of left ventricular systolic function(LVSF)damage in DM is essential.AIM To explore the use of the three-dimensional speckle tracking technique(3D-STI)for measuring LVSF in DM patients via meta-analysis.METHODS The electronic databases were retrieved from the initial accessible time to 29 April 2023.The current study involved 9 studies,including 970 subjects.We carried out this meta-analysis to estimate myocardial function in DM compared with controls according to myocardial strain attained by 3D-STI.RESULTS Night articles including 970 subjects were included.No significant difference was detected in the left ventricular ejection fraction between the control and the diabetic group(P>0.05),while differences in global longitudinal strain,global circumferential strain,global radial strain,and global area strain were markedly different between the controls and DM patients(all P<0.05).CONCLUSION The 3D-STI could be applied to accurately measure early LVSF damage in patients with DM.

Evolvement of left ventricular assist device： the implications on heart failure management

Heart failure （HF） is a potentially fatal disease that affects increasing number of people worldwide. Although heart transplant is the ＂gold standard＂ therapy for HF, due to the limited availability of organs, many patients died when waiting for the transplant. Left ventricular assist device （LVAD）, as a mechanical circulatory support, has become a new light for patients with HF. With the technical advancements, LVADs work not only as a bridge to transplant, but also assist heart recovery and even as a destination therapy in long-term treatment. This observation paper reviewed the development of LVAD and its clinical roles. The challenges and possible solutions in nursing care for pa- tients with LVAD at different stage of implantation were discussed. The healthcare professionals could obtain a better understanding about the LVAD treatment for HF patients.

Off-Pump Coronary Artery Bypass Grafting in Patients with Left Ventricular Dysfunction: Short-Term Results from a Single Center in Bangladesh

Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-term outcomes and functional improvements in LVD patients post-OPCAB. Methods: The study included 200 coronary artery disease patients who underwent isolated off-pump coronary artery bypass grafting (OPCAB) at the National Heart Foundation Hospital and Research Institute between January 2019 and June 2020. Patients were categorized into Group 1, with a left ventricular ejection fraction (LVEF) of 30% - 39%, and Group 2, with an LVEF of 40% or higher. Echocardiographic assessments of left ventricular dimensions and ejection fraction were performed preoperatively, at discharge, and one month postoperatively. Results: In Group 1, preoperative left ventricular internal dimensions during diastole (LVIDd) and systole (LVIDs) were 53.48 ± 4.40 mm and 44.23 ± 3.93 mm, respectively, with a left ventricular ejection fraction (LVEF) of 35.28% ± 2.26%. At discharge, these values improved to 51.58 ± 4.04 mm (LVIDd), 41.23 ± 5.30 mm (LVIDs), and 39.25% ± 3.75% (LVEF). One month postoperatively, further improvements were observed: 46.29 ± 3.76 mm (LVIDd), 37.45 ± 3.68 mm (LVIDs), and 43.22% ± 4.67% (LVEF). Group 2 showed similar positive outcomes, with preoperative values of 47.09 ± 5.06 mm (LVIDd), 35.11 ± 5.25 mm (LVIDs), and 50.13% ± 7.25% (LVEF), improving to 42.37 ± 4.18 mm (LVIDd), 31.05 ± 4.19 mm (LVIDs), and 55.33% ± 7.05% (LVEF) at one month postoperatively. Both groups demonstrated significant improvements in left ventricular function and NYHA class, with most patients moving from class III/IV to I/II. Complications were minimal, and no mortality was observed. Conclusion: OPCAB is safe and effective for patients with LVEF 30% - 39% and LVEF ≥ 40%, providing significant short-term functional improvements without increased risk.

Multiple left ventricular myxomas combined with severe rheumatic valvular lesions: A case report

BACKGROUND Primary cardiac tumors are uncommon,of which cardiac myxoma accounts for 50%-80%.Left ventricular myxoma has been rarely reported,accounting for only 3%-4%of all cardiac myxomas.Multiple left ventricular myxomas are,relatively,even rarer.CASE SUMMARY In this report,we present a case of multiple left ventricular myxomas combined with severe rheumatic valve lesions.Symptomatically,the patient presented with fatigue,shortness of breath,and palpitation after activities.The patient underwent complete surgical resection of multiple left ventricular myxomas combined with mechanical replacement of the mitral and aortic valves,tricuspid valvuloplasty.The patient recovered well after the operation,with no obvious related complications.CONCLUSION Multiple left ventricular myxomas may coexist with severe rheumatic valve disease.Operation is an effective treatment.

Change and impact of left ventricular global longitudinal strain during transcatheter aortic valve implantation

BACKGROUND Although transcatheter aortic valve implantation(TAVI)is a safe and effective treatment for aortic stenosis,it still carries some risks,such as valve leaks,stroke,and even death.The left ventricular global longitudinal strain(LVGLS)measurement may be useful for the prediction of adverse events during this operation.AIM To explore the change of LVGLS during TAVI procedure and the relationship between LVGLS and perioperative adverse events.METHODS In this study,61 patients who had undergone percutaneous transfemoral TAVI were evaluated by transthoracic echocardiography.Before surgery,data on left ventricular ejection fraction(LVEF)and LVGLS were collected separately following balloon expansion and stent implantation.Difference in values of LVGLS and LVEF during preoperative balloon expansion(pre-ex),preoperative stent implantation(pre-im)and balloon expansion-stent implantation(ex-im)were also examined.Adverse events were defined as perioperative death,cardiac rupture,heart arrest,moderate or severe perivalvular leakage,significant mitral regurgitation during TAVI,perioperative moderate or severe mitral regurgitation,perioperative left ventricular outflow tract obstruction,reoperation,and acute heart failure.RESULTS The occurrence of perioperative adverse events was associated with differences in pre-ex LVGLS,but not with difference in pre-ex LVEF.There were significant differences between pre-LVGLS and ex-LVGLS,and between pre-LVGLS and im-LVGLS(P=0.037 and P=0.020,respectively).However,differences in LVEF were not significant(P=0.358,P=0.254);however differences in pre-ex LVGLS were associated with pre-LVGLS(P=0.045).Compared to LVEF,LVGLS is more sensitive as a measure of left heart function during TAVI and the perioperative period.Moreover,the differences in LVGLS were associated with the occurrence of perioperative adverse events,and changes in LVGLS were apparent in patients with undesirable LVGLS before the surgery.Furthermore,LVGLS is useful to predict changes in cardiac function during TAVI.CONCLUSION Greater attention should be paid to the patients who plan to undergo TAVI with normal LVEF but poor LVGLS.

The Influence of Ethnicity in the Relationship between Sedentary Screen Time and Left Ventricular Mass: Insights from the MAG-SALVAGES

Background: The influence of race/ethnicity on the relationship between sedentary screen time and left ventricular mass has been recently suggested, but remains a subject of debate, and has never been explored in Africa. Purpose: To determine whether there is a racial/ethnic influence on the relationship between sedentary screen time and left ventricular mass in MAGhreb and Sub Saharan Africa Left-Ventricul ArGEometry Study (MAG-SALVAGES) participants. Methods: 100 blacks sub-Saharan African and 187 white Maghreb aged 18 - 55 years underwent an interview on their behavioral measures, physical activity and eating habits. Their left ventricular mass has also been measured by a resting transthoracic echography according to the American Society of Echography. Generalized linear models evaluated a test-for-trend across higher levels of sedentary screen time in progressive models with left ventricular measurements as dependent variables. The study population was stratified into quartiles of sedentary screen time (separately for whites and blacks) and examined the joint association of sedentary screen time and LVM within quartiles of physical activity. Results: Among White Maghreb, higher screen time was associated with smaller left ventricular mass (P Conclusions: Sedentary screen time is associated with smaller left ventricular mass in White Maghreb, not in black sub-Saharan African. The lack of association in blacks supports a potential qualitative difference in the cardiovascular consequences of sedentary screen based behavior.

Evaluation of Left Ventricular Systolic Function after Pulmonary Valve Replacement Using Cardiovascular Magnetic Resonance Imaging

Following reparative surgery for tetralogy of Fallot or critical pulmonary stenosis(PS),patients frequently present with severe right ventricular(RV)volume overload due to pulmonary regurgitation,resulting in decreased RV function.Surgical pulmonary valve replacement(PVR)is known to improve RV function,but changes in left ventricular(LV)function after PVR have rarely been described.We sought to determine the midterm results regarding LV systolic function after PVR using cardiac MRI in 40 consecutive patients with repaired TOF(31 patients)or PS(9 patients)with an age of 29±9 years who underwent PVR from 2006 to 2011 at a single center.Cardiac MRI RV and LV volumes before and after PVR were analyzed.Demographics,clinical variables,cardiopulmonary bypass duration,and medications were reviewed.LV ejection fraction(LVEF)increased from(54±8)to(57±6)%(P=0.02).Before PVR,26 patients had depressed LVEF of(49±5)%(range 36– 54%).In this group,LVEF increased by(7±7)%(P<0.0001)after PVR.Low LVEF before PVR was correlated with increased LVEF after PVR(regression coefficient-0.7,R 2=0.59,P<0.0001).Demographics,medications,prior pregnancies,and cardiopulmonary bypass duration had no effect on LVEF after PVR.The increase in LVEF was most significant in patients with low pre-PVR LVEF.

Left Ventricular Reconstruction and Mitral Valve Annuloplasty Combined with Papillary Muscle Relocation for Severe Ischemic Mitral Regurgitation

A 46-year-old man was referred to our hospital due to severe ischemic mitral regurgitation with severe bileaflet tethering and a dilated left ventricle. We performed left ventricular reconstruction and mitral valve annuloplasty combined with papillary muscle relocation. Although left ventricular continued remodeling occurred during follow-up, left ventricular reconstruction and mitral valve annuloplasty combined with papillary muscle relocation provided durable mitral repair, and his functional status was good. Thus, this combined surgical treatment may reduce mitral regurgitation recurrence after mitral valve annuloplasty.

Impact of severe left ventricular dysfunction on mid-term mortality in elderly patients undergoing transcatheter aortic valve implantation

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.

Bicuspid aortic valve with associated aortopathy, significant left ventricular hypertrophy or concomitant hypertrophic cardiomyopathy: A diagnostic and therapeutic challenge

Due to its prevalence of 0.5%to 2%in the general population,with a 75%predominance among men,bicuspid aortic valve is the most common congenital heart defect.It is frequently accompanied by other cardiac congenital anomalies,and clinical presentation can vary significantly,with stenosis being the most common manifestation,often resulting in mild to moderate concentric hypertrophy of the left ventricle.Echocardiography is the primary diagnostic modality utilized for establishing the diagnosis,and it is often the sole diagnostic tool relied upon by clinicians.However,due to the heterogeneous clinical presentation and possible associated anomalies(which are often overlooked in clinical practice),it is necessary to employ various diagnostic methods and persist in finding the accurate diagnosis if multiple inconsistencies exist.By employing this approach,we can effectively manage these patients and provide them with appropriate treatment.Through a clinical case from our practice,we provide an overview of the literature on bicuspid aortic valve with aortophaty and the possible association with hypertrophic cardiomyopathy,diagnostic methods,and treatment options.This review article highlights the critical significance of achieving an accurate diagnosis in patients with bicuspid aortic valve and significant left ventricular hypertrophy.It is crucial to exclude other possible causes of left ventricular outflow tract obstruction,such as sub-or supra-aortic obstructions,and hypertrophic cardiomyopathy.

Genetic Association Study of KCNB1 Gene with the Susceptibility of Hypertension Related LVH （Left Ventricular Hypertrophy） Patients in Malaysia

LVH （Left ventricular hypertrophy） is an independent risk factor for the development of heart failure, cardiac arrhythmias and stroke. A recent genome-wide association study reported the involvement of a candidate gene namely KCNBI in mechanism for development of LVH in hypertension. This study aimed to replicate the finding by investigating the genetic association of KCNBI gene among the hypertensive LVH patients from Malaysia. We genotyped a SNP （single nucleotide polymorphism） located in KCNBI namely, rs6063397 among 200 subjects consisting of61 LVH and 139 non LVH patients using Sanger sequencing method. Statistical analysis revealed no significant association between the L VH susceptibility between the allele and genotype frequencies （P = 0.2719 and 0.4768, respectively）. This finding suggests that KCNBI may not playa role in LVH susceptibility in hypertensive patients in Southeast Asian populations.

Effect of aortic valve replacement on ventricular recovery and functional class in patients with reduced left ventricular function

Objective: The aim of the study was to assess the effects of aortic valve replacement (AVR) in patients with aortic stenosis (AS) or regurgitation (AR) and left ventricular (LV) dysfunction. Patients and methods: Retrospective analysis identified 75 consecutive patients with left ventricular ejection fraction (LVEF) assessed by echocardiography < 40% who underwent AVR for AS (n = 40) or AR (n = 35) between 1994 and 2011. Exclusion criteria were previous myocardial infarction or concomitant valvular disorders other than aortic disease. Follow-up evaluated the New York Heart Association (NYHA) functional class, LVEF and survival rate. Results: Mean ages were respectively 56.5 ± 9.3 and 47.9 ± 11.7 years in AS and AR groups, p = 0.001. Before surgery, 88% and 75% of patients were in NYHA III-IV respectively in AS and AR. In the AS group, the mean LVEF and aortic valve area (AVA) were respectively 32.2% ± 8% and 0.65 ± 0.15 cm2. AR group had a mean LVEF of 33.8 ± 6.7% and a mean LV systolic diameter of 62 ± 8.8 mm. All patients underwent AVR under cardiopulmonary bypass. There were 5 operative deaths (12.5%) in AS group and 6 (17.6%) in AR group, p = 0.57. LVEF increased to 49% ± 14.7% and 51.2% ± 10.9% in the AS and AR groups after echocardiography control. The survival rates at 1, 5 and 10 years were respectively 94.4%, 87% and 80% in AS group and 95.2%, 93% and 89% in AR group. Conclusion: Despite higher perioperative mortality in patients with aortic valve disease (AS or AR) and LV dysfunction, long-term outcome is excellent. We, therefore, conclude that AVR can be performed and it should not be denied to patients on the basis of low EF alone.

Plasma Norepinephrine and Hemorheology in Essential Hypertensive Patients with Different Patterns of Left Ventricular Hypertrophy

对80例不同类型高血压左室肥厚（LVH）患者的血浆去甲肾上腺素（NE）和血液流变学改变进行观察。结果显示，（1）向心性肥厚组（CH）高切变率下全血粘度（WBV230）显著升高；（2）不对称性室间隔肥厚组（ASH）血浆NE和收缩末期室壁应力（ESS）增高较明显；（3）多元回归分析显示，SBP，ESS和血浆NE是影响相对室壁厚度的重要因素。提示CH是一种对压力负荷过重而产生的代偿形式；ASH的形成除了负荷因素外血浆NE可能起更重要的作用。

Left ventricular regional and global diastolic function assessed using Quantitative Tissue velocity Imaging in patients with hypertrophic cardiomyopathy

Objectives The study was performed to assess the left ventricular (LV) regional and global diastolic function、left ventricular wall motion features in patients with Hypertrophic cardiomyopathy by Quantitative Tissue Velocity Imaging (QTVI). Methods 42 patients with hypertrophic cardiomyopathy and 36 age-matched normal subjects underwent QTVI study. Off-line LV regional muscular tissue velocity Imaging along LV apical long-axis view were obtained. Regional diastolic function was assessed in using peak tissue velocities of LV regional muscular tissue during early diastole (Ve)and LA contraction (Va), Ve/Va ratio, derived from Tissue Velocity Imaging. Global diastolic function was reflected by isovolumic relaxation time(IRT) and mitral valve peak flow velocity ( E/A ) calculated with pulsed wave doppler. The end-diastolic interventricular septal thickness (ⅣSt) was measured by conventional 2 - dimension echocardiography. Results ① Ve、 Va、 Ve/Va in the segments of hypertrophic interventricular septum (IVS) reduced wlhile E/A ratio significantly reduced and IRT markedly prolonged in HCM patients than in normal subjects。 ② Ve、 Ve/Va were significant reduced in the segments of hypertrophic interventricular septum compared with other LV segments in HCM patients . ③ There was a correlation between Ve/Va and E/A in HCM patients with abnormal E/A ratio (r = 0. 70). ④ There was a negative correlation between Ve/Va and ⅣSt in non -obstruction HCM patients (B group , r = -0.61 ) Conclusions QTVI offers a newer method in clinical practice which has a higher sensibility and accuracy in evaluating the LV regional and global diastolic function in HCM patients .