ACTA PHYSIOLOGICA, Issue 2 2010
G. D. K. Matthews
Abstract Aim:, Clinical observations suggest that alternans in action potential (AP) characteristics presages breakdown of normal ordered cardiac electrical activity culminating in ventricular arrhythmogenesis. We compared such temporal nonuniformities in monophasic action potential (MAP) waveforms in left (LV) and right ventricular (RV) epicardia and endocardia of Langendorff-perfused murine wild-type (WT), and Scn5a+/, hearts modelling Brugada syndrome (BrS) for the first time. Methods:, A dynamic pacing protocol imposed successively incremented steady pacing rates between 5.5 and 33 Hz. A signal analysis algorithm detected sequences of >10 beats showing alternans. Results were compared before and following the introduction of flecainide (10 ,m) and quinidine (5 ,m) known to exert pro- and anti-arrhythmic effects in BrS. Results:, Sustained and transient amplitude and duration alternans were both frequently followed by ventricular ectopic beats and ventricular tachycardia or fibrillation. Diastolic intervals (DIs) that coincided with onsets of transient (tr) or sustained (ss) alternans in MAP duration (DI*) and amplitude (DI,) were determined. Kruskal,Wallis tests followed by Bonferroni-corrected Mann,Whitney U -tests were applied to these DI results sorted by recording site, pharmacological conditions or experimental populations. WT hearts showed no significant heterogeneities in any DI. Untreated Scn5a+/, hearts showed earlier onsets of transient but not sustained duration alternans in LV endocardium compared with RV endocardium or LV epicardium. Flecainide administration caused earlier onsets of both transient and sustained duration alternans selectively in the RV epicardium in the Scn5a+/, hearts. Conclusion:, These findings in a genetic model thus implicate RV epicardial changes in the arrhythmogenicity produced by flecainide challenge in previously asymptomatic clinical BrS. [source]

Downregulation of oxytocin receptors in right ventricle of rats with monocrotaline-induced pulmonary hypertension

ACTA PHYSIOLOGICA, Issue 2 2010
T. L. Broderick
Abstract Aim:, Pulmonary hypertension (PH) in the rat leads to right ventricular (RV) hypertrophy, inflammation and increased natriuretic peptide (NP) levels in plasma and RV. Because the release of nitric oxide (NO) and atrial natriuretic peptide (ANP) is a function of the oxytocin receptor (OTR), we examined the effect of PH on gene and protein expression of OTR, NP (A, atrial; B, brain) and receptors (NPRs), nitric oxide synthases (NOS), interleukin (IL)-1,, IL-6 and tumour necrosis factor-, in the hypertrophied RV in a model of PH. Methods:, RV hypertrophy was induced in male Sprague,Dawley rats with monocrotaline (MCT; 60 mg kg,1) and was confirmed by the presence of an increased RV weight and RV-to-[left ventricle (LV) and septum] ratio. Results:, In the RV of MCT-treated rats, a ,40% reduction in OTR mRNA and protein was observed compared with the RV of control rats. This reduction was associated with increased transcripts of ANP and BNP in both ventricles and a corresponding increase in NP receptor mRNA expression for receptors A, B and C. Protein expression of inducible NOS was increased in the RV, whereas endothelial NOS transcripts were increased only in the LV of MCT-treated rats. In the RV of MCT-treated rats, downregulation of OTR was also associated with increased mRNA expression of IL-1, and IL-6. Conclusion:, Our results show that downregulation of the OTR in the RV of MCT-treated rats is associated with increased expression of NP and their receptors as well as IL-1, and IL-6. This reduction in OTR in RV myocardium may have an impact on cardiac function in the MCT-induced model of PH. [source]

Late Presenters with Dextro-transposition of Great Arteries and Intact Ventricular Septum: To Train or Not to Train the Left Ventricle for Arterial Switch Operation?

CONGENITAL HEART DISEASE, Issue 6 2009
Noor Mohamed Parker MBChB
ABSTRACT Objective., We report our experience in managing late presenters (older than 4 weeks) with dextro-transposition of great arteries and intact ventricular septum (d-TGA/IVS) in an effort to achieve successful arterial switch operation (ASO) in a third world setting. Design., We retrospectively reviewed the charts of all late presenters with d-TGA/IVS. Patients were divided into two groups: left ventricular training (LVT) group and non-left ventricular training (non-LVT) group. LVT group underwent pulmonary artery banding and Blalock-Taussig Shunt prior to ASO. Results., Twenty-one late presenters were included in the study. In LVT group, 11 patients with median age of 6 months (range, 1,72 months) underwent LVT. Later, 8 patients with median age of 9.25 months (range, 1.33,84 months) underwent ASO. Prior to ASO, left ventricle (LV) collapse resolved in all and left ventricle to systemic pressure (LV/SP) ratio was 0.81 (range, 0.76,0.95) in 4 patients. Two patients who had LVT for ,14 days required postoperative extracorporeal membrane oxygenation (ECMO) support due to LV dysfunction. Seven patients survived to discharge. In non-LVT group, 10 patients with median age of 2.5 months (range, 1,98 months) underwent ASO. Five patients had LV collapse, and median LV/SP ratio was 0.67 (range, 0.56,1.19) in 5 patients. Seven patients needed ECMO support. Seven patients survived to discharge. Conclusion., Late presenters with d-TGA/IVS, who have LV collapse on echocardiography and/or a LV/SP ratio <0.67 on cardiac catheterization, should be subjected to LVT preferably for duration of longer than 14 days in order to avoid potential ECMO use. [source]

Identifying Left Ventricular Dysfunction in Pulmonary Hypertension

CONGESTIVE HEART FAILURE, Issue 5 2009
Navin Rajagopalan MD
The significance of left ventricular (LV) dysfunction in patients with pulmonary hypertension (PH) is unknown. Our purpose was to quantify LV function in PH patients by measuring LV myocardial performance index (MPI) and correlating it with invasively determined hemodynamic variables. The authors prospectively measured LV MPI via transthoracic echocardiography in 50 patients with PH (53±11 years; 35 women) who also underwent right heart catheterization within 1 day of echocardiography. For comparative purposes, LV MPI was also measured in 15 healthy volunteers who served as controls. LV MPI was significantly increased in the PH group compared with controls (0.62±0.27 vs 0.36±0.08; P<.001), indicating worse LV dysfunction despite that LV ejection fraction was not significantly different between the groups (58%±4% vs 60%±3%). LV MPI demonstrated significant correlations with invasively determined mean pulmonary artery pressure (r=.50; P<.001), pulmonary vascular resistance (r=.57; P<.001), and cardiac index (r=,.64; P<.001). By receiver operating characteristic analysis, LV MPI >0.75 predicted cardiac index <2 L/min/m2 with 89% sensitivity and 78% specificity (area under the curve, 0.89). In a multivariate model, LV MPI was independently associated with cardiac index (P<.01). Patients with PH demonstrate abnormal LV function as quantified by elevated LV MPI, which correlates significantly with pulmonary vascular resistance and cardiac index. [source]

Baseline Characteristics of Patients Randomized in the Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction (REVERSE) Study

CONGESTIVE HEART FAILURE, Issue 2 2008
Cecilia Linde MD
The Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction (REVERSE) study is a randomized controlled trial currently assessing the safety and efficacy of cardiac resynchronization therapy in patients with asymptomatic left ventricular (LV) dysfunction with previous symptoms of mild heart failure. This paper describes the baseline characteristics of randomized patients; 610 patients with New York Heart Association (NYHA) class II (82.3%) heart failure or asymptomatic (NYHA class I) LV dysfunction with previous symptoms (17.7%) were randomized in 73 centers. The mean age was 62.5±11.0 years, the mean LV ejection fraction was 26.7%±7.0%, and the mean LV end-diastolic diameter was 66.9±8.9 mm. A total of 97% of patients were taking angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and 95.1% were taking ,-blockers, which were at the target dose in 35.1% of patients. Compared with previous randomized cardiac resynchronization therapy trials, REVERSE patients are on better pharmacologic treatment, are younger, and have a narrower QRS width despite similar LV dysfunction. [source]

Presence of Biventricular Dysfunction in Patients With Type II Diabetes Mellitus

CONGESTIVE HEART FAILURE, Issue 2 2007
Mohammad-Reza Movahed MD
Diabetes mellitus (DM) has been found to be associated with depressed left ventricular (LV) function. Right ventricular (RV) function in DM patients, however, has not been well studied. The goal of this study was to evaluate the occurrence of LV and RV dysfunction in patients with DM. A series of 157 patients underwent simultaneous measurement of LV ejection fraction (LVEF) and RV ejection fraction (RVEF). Four of 26 DM patients had RVEF <30% (15.4%) vs 4 of 126 controls (3.2%) (P=.01). Eleven of 27 (40.7%) patients with DM had LVEF <30% vs 9 of 128 controls (7%) (P<.0001). Using multivariate analysis, DM remained independently associated with severely decreased biventricular function (RVEF <30%; odds ratio, 5.7; confidence interval, 1.3,25.4 [P=.02] and LVEF <30%; odds ratio, 12.9; confidence interval, 3.8,43.7 [P<.0001]). These results suggest that diabetic cardiomyopathy involves both ventricles as an independent pathologic process. [source]

Feasibility of Biventricular Pacing in Patients With Recent Myocardial Infarction: Impact on Ventricular Remodeling

CONGESTIVE HEART FAILURE, Issue 1 2007
Eugene S. Chung MD
To test the hypothesis that biventricular pacing after a myocardial infarction with reduced ejection fraction can attenuate left ventricular (LV) remodeling, the authors studied 18 patients (myocardial infarction within 30,45 days, ejection fraction ,30%, narrow QRS) randomized to biventricular therapy (biventricular therapy + defibrillator) (biventricular group) or implantable cardioverter-defibrillator alone (control group). At 1, 6, and 12 months, there were no differences in functional or clinical parameters (New York Heart Association, quality of life, 6-minute walk). Twelve-month LV volume remained stable in the biventricular group, but increased in the control group (median LV end-diastolic volume increase, 6.5 mL in biventricular vs 35 mL in control; P=.03; median LV end-diastolic volume decrease, 5.5 mL in biventricular vs 30.5-mL increase in control; P=.11). Biventricular therapy also prevented an increase in sphericity index at 12 months (median, ,2% in biventricular vs 37% in control; P=.06). Delivery of biventricular therapy early after myocardial infarction appears safe and feasible and may attenuate subsequent LV dilation. [source]

Effect of reduced total blood volume on left ventricular volumes and kinetics in type 2 diabetes

ACTA PHYSIOLOGICA, Issue 1 2010
S. Lalande
Abstract Aim:, Although impaired left ventricular (LV) diastolic function is commonly observed in patients with type 2 diabetes, it remains unclear whether the impairment is caused by altered LV relaxation or changes in LV preload. The purpose of this study was to examine the influence of LV function and LV loading conditions on stroke volume in men with type 2 diabetes. Methods:, Cardiac magnetic resonance imaging scans were performed in eight men with type 2 diabetes and 11 non-diabetic men matched for age, weight and physical activity level. Total blood volume was determined with the Evans blue dye dilution technique. Results:, End-diastolic volume (EDV), the ratio of peak early to late mitral inflow velocity (E/A) and stroke volume were lower in men with type 2 diabetes than in non-diabetic individuals. Peak filling rate and peak ejection rate were not different between diabetic and non-diabetic individuals; however, men with type 2 diabetes had proportionally longer systolic duration than non-diabetic individuals. Heart rate was higher and total blood volume was lower in men with type 2 diabetes. The lower total blood volume was correlated with a lower EDV in men with type 2 diabetes. Conclusions:, Men with type 2 diabetes have an altered cardiac cycle and lower end-diastolic and stroke volume. A lower total blood volume and higher heart rate in men with type 2 diabetes suggest that changes in LV preload, independent of changes in LV relaxation or contractility, influence LV diastolic filling and stroke volume in this population. [source]

Cardiac function during mild hypothermia in pigs: increased inotropy at the expense of diastolic dysfunction

ACTA PHYSIOLOGICA, Issue 1 2010
H. Post
Abstract Aim:, The induction of mild hypothermia (MH; 33 °C) has become the guideline therapy to attenuate hypoxic brain injury after out-of-hospital cardiopulmonary resuscitation. While MH exerts a positive inotropic effect in vitro, MH reduces cardiac output in vivo and is thus discussed critically when severe cardiac dysfunction is present in patients. We thus assessed the effect of MH on the function of the normal heart in an in vivo model closely mimicking the clinical setting. Methods:, Ten anaesthetized, female human-sized pigs were acutely catheterized for measurement of pressure,volume loops (conductance catheter), cardiac output (Swan-Ganz catheter) and for vena cava inferior occlusion. Controlled MH (from 37 to 33 °C) was induced by a vena cava inferior cooling catheter. Results:, With MH, heart rate (HR) and whole body oxygen consumption decreased, while lactate levels remained normal. Cardiac output, left ventricular (LV) volumes, peak systolic and end-diastolic pressure and dP/dtmax did not change significantly. Changes in dP/dtmin and the time constant of isovolumetric relaxation demonstrated impaired active relaxation. In addition, MH prolonged the systolic and shortened the diastolic time interval. Pressure,volume analysis revealed increased end-systolic and end-diastolic stiffness, indicating positive inotropy and reduced end-diastolic distensibility. Positive inotropy was preserved during pacing, while LV end-diastolic pressure increased and diastolic filling was substantially impaired due to delayed LV relaxation. Conclusion:, MH negatively affects diastolic function, which, however, is compensated for by decreased spontaneous HR. Positive inotropy and a decrease in whole body oxygen consumption warrant further studies addressing the potential benefit of MH on the acutely failing heart. [source]

Single-beat estimation of the left ventricular end-systolic pressure,volume relationship in patients with heart failure

ACTA PHYSIOLOGICA, Issue 1 2010
E. A. Ten Brinke
Abstract Aim:, The end-systolic pressure,volume relationship (ESPVR) constructed from multiple pressure,volume (PV) loops acquired during load intervention is an established method to asses left ventricular (LV) contractility. We tested the accuracy of simplified single-beat (SB) ESPVR estimation in patients with severe heart failure. Methods:, Nineteen heart failure patients (NYHA III-IV) scheduled for surgical ventricular restoration and/or restrictive mitral annuloplasty and 12 patients with normal LV function scheduled for coronary artery bypass grafting were included. PV signals were obtained before and after cardiac surgery by pressure-conductance catheters and gradual pre-load reductions by vena cava occlusion (VCO). The SB method was applied to the first beat of the VCO run. Accuracy was quantified by the root-mean-square-error (RMSE) between ESPVRSB and gold-standard ESPVRVCO. In addition, we compared slopes (EES) and intercepts (end-systolic volume at multiple pressure levels (70,100 mmHg: ESV70,ESV100) of ESPVRSB vs. ESPVRVCO by Bland,Altman analyses. Results:, RMSE was 1.7 ± 1.0 mmHg and was not significantly different between groups and not dependent on end-diastolic volume, indicating equal, high accuracy over a wide volume range. SB-predicted EES had a bias of ,0.39 mmHg mL,1 and limits of agreement (LoA) ,2.0 to +1.2 mmHg mL,1. SB-predicted ESVs at each pressure level showed small bias (range: ,10.8 to +9.4 mL) and narrow LoA. Two-way anova indicated that differences between groups were not dependent on the method. Conclusion:, Our findings, obtained in hearts spanning a wide range of sizes and conditions, support the use of the SB method. This method ultimately facilitates less invasive ESPVR estimation, particularly when coupled with emerging noninvasive techniques to measure LV pressures and volumes. [source]

Electrophysiological determinants of hypokalaemia-induced arrhythmogenicity in the guinea-pig heart

ACTA PHYSIOLOGICA, Issue 4 2009
O. E. Osadchii
Abstract Aim:, Hypokalaemia is an independent risk factor contributing to arrhythmic death in cardiac patients. In the present study, we explored the mechanisms of hypokalaemia-induced tachyarrhythmias by measuring ventricular refractoriness, spatial repolarization gradients, and ventricular conduction time in isolated, perfused guinea-pig heart preparations. Methods:, Epicardial and endocardial monophasic action potentials from distinct left ventricular (LV) and right ventricular (RV) recording sites were monitored simultaneously with volume-conducted electrocardiogram (ECG) during steady-state pacing and following a premature extrastimulus application at progressively reducing coupling stimulation intervals in normokalaemic and hypokalaemic conditions. Results:, Hypokalaemic perfusion (2.5 mm K+ for 30 min) markedly increased the inducibility of tachyarrhythmias by programmed ventricular stimulation and rapid pacing, prolonged ventricular repolarization and shortened LV epicardial and endocardial effective refractory periods, thereby increasing the critical interval for LV re-excitation. Hypokalaemia increased the RV-to-LV transepicardial repolarization gradients but had no effect on transmural dispersion of APD90 and refractoriness across the LV wall. As determined by local activation time recordings, the LV-to-RV transepicardial conduction and the LV transmural (epicardial-to-endocardial) conduction were slowed in hypokalaemic heart preparations. This change was attributed to depressed diastolic excitability as evidenced by increased ventricular pacing thresholds. Conclusion:, These findings suggest that hypokalaemia-induced arrhythmogenicity is attributed to shortened LV refractoriness, increased critical intervals for LV re-excitation, amplified RV-to-LV transepicardial repolarization gradients and slowed ventricular conduction in the guinea-pig heart. [source]

Diagnostic utility of brain-natriuretic peptide for left ventricular diastolic dysfunction in asymptomatic type 2 diabetic patients

DIABETES OBESITY & METABOLISM, Issue 3 2007
M. Shimabukuro
Aim:, Left ventricular (LV) diastolic dysfunction has been reported to be prevalent in diabetic subjects, but this recognition could often be missed. We evaluated prevalence of LV diastolic dysfunction and diagnostic utility of brain-natriuretic peptide (BNP) in asymptomatic patients with type 2 diabetes mellitus. Research design and methods:, Plasma BNP levels and LV geometry and diastolic filling indices, including the ratio of peak early transmitral Doppler flow (E) over flow propagation velocity (Vp) measured by colour M-mode Doppler echocardiography, were analysed in 98 consecutive asymptomatic patients with type 2 diabetes mellitus and 51 age-matched controls. Results:, The LV mass index and relative wall thickness were higher in diabetic groups than controls without any differences in LV systolic function. The frequency of diastolic dysfunction defined as E/Vp , 1.5 were 31% in diabetic groups and 15% in controls (,2 = 4.364, p = 0.037). By receiver-operating characteristic (ROC) curve analysis, a BNP cutoff value of 19.2 pg/ml in controls had a 53.1% positive predictive value (53.1%) and a high negative predictive value (94.4%) for E/Vp , 1.5, whereas a BNP cutoff value of 18.1 pg/ml in diabetic groups had a 61.8% positive and 97.3% negative predictive values. Conclusions:, The frequency of E/Vp , 1.5 was higher in asymptomatic diabetic patients, suggesting that LV diastolic dysfunction was prevalent. The plasma concentration of BNP could be used to depict LV diastolic dysfunction in such population. [source]

Left ventricular diastolic dysfunction in patients with chronic renal failure: impact of diabetes mellitus

DIABETIC MEDICINE, Issue 6 2005
J. Miyazato
Abstract Aims Left ventricular (LV) hypertrophy and LV diastolic dysfunction are cardiac changes commonly observed in patients with chronic renal failure (CRF) as well as hypertension. Although the impairment of LV diastolic function in patients with diabetes mellitus has been shown, little is known about the specific effect of diabetes on LV diastolic function in patients with CRF. The present study was designed to investigate the impact of diabetic nephropathy on LV diastolic dysfunction, independent of LV hypertrophy, in CRF patients. Methods In 67 patients with non-dialysis CRF as a result of chronic glomerulonephritis (n = 33) or diabetic nephropathy (n = 34), and 134 hypertensive patients with normal renal function, two-dimensional and Doppler echocardiographic examinations were performed, and LV dimension, mass, systolic function, and diastolic function were evaluated. Results LV mass was increased and LV diastolic dysfunction was advanced in subjects with CRF compared with hypertensive controls. In the comparison of echocardiographic parameters between the two groups of CRF patients, i.e. chronic glomerulonephritis and diabetic nephropathy groups, all indices of LV diastolic function were more deteriorated in the diabetic nephropathy group than in the chronic glomerulonephritis group, although LV structure including hypertrophy and systolic function did not differ between the groups. In a multiple regression analysis, the presence of diabetes (i.e. diabetic nephropathy group) was a significant predictor of LV diastolic dysfunction in CRF subjects, independent of other influencing factors such as age, blood pressure, renal function, anaemia and LV hypertrophy. Conclusion The present findings suggest that LV diastolic dysfunction, independent of LV hypertrophy, is specifically and markedly progressed in patients with CRF as a result of diabetic nephropathy. [source]

"Supranormal" Cardiac Function in Athletes Related to Better Arterial and Endothelial Function

ECHOCARDIOGRAPHY, Issue 6 2010
Maria Florescu M.D.
Objective: Athlete's heart is associated with left ventricular (LV) hypertrophy (LVH), and "supranormal" cardiac function, suggesting that this is a physiological process. Hypertrophy alone cannot explain increase in cardiac function, therefore, other mechanisms, such as better ventriculo-arterial coupling might be involved. Methods: We studied 60 male (21 ± 3 years) subjects: 27 endurance athletes, and a control group of 33 age-matched sedentary subjects. We assessed global systolic and diastolic LV function, short- and long-axis myocardial velocities, arterial structure and function and ventriculo-arterial coupling, endothelial function by flow-mediated dilatation, and amino-terminal pro-brain natriuretic peptide (NT-proBNP) and biological markers of myocardial fibrosis and of oxidative stress. Results: Athletes had "supranormal" LV longitudinal function (12.4 ± 1.0 vs 10.1 ± 1.4 cm/s for longitudinal systolic velocity, and 17.4 ± 2.6 vs 15.1 ± 2.4 cm/s for longitudinal early diastolic velocity, both P < 0.01), whereas ejection fraction and short-axis function were similar to controls. Meanwhile, they had better endothelial function (16.7 ± 7.0 vs 13.3 ± 5.3%, P < 0.05) and lower arterial stiffness (pulse wave velocity 7.1 ± 0.6 vs 8.8 ± 1.1 m/s, P = 0.0001), related to lower oxidative stress (0.259 ± 0.71 vs 0.428 ± 0.88 nmol/mL, P = 0.0001), with improved ventriculo-arterial coupling (37.1 ± 21.5 vs 15.5 ± 13.4 mmHg.m/s3× 103, P = 0.0001). NT-proBNP and markers of myocardial fibrosis were not different from controls. LV longitudinal function was directly related to ventriculo-arterial coupling, and inversely related to arterial stiffness and to oxidative stress. Conclusions: "Supranormal" cardiac function in athletes is due to better endothelial and arterial function, related to lower oxidative stress, with optimized ventriculo-arterial coupling; athlete's heart is purely a physiological phenomenon, associated with "supranormal" cardiac function, and there are no markers of myocardial fibrosis. (Echocardiography 2010;27:659-667) [source]

Contractile Reserve Assessed Using Dobutamine Echocardiography Predicts Left Ventricular Reverse Remodeling after Cardiac Resynchronization Therapy: Prospective Validation in Patients with Left Ventricular Dyssynchrony

ECHOCARDIOGRAPHY, Issue 6 2010
F.R.C.P.C., Mario Sénéchal M.D.
Background: The presence of viable myocardium may predict response to cardiac resynchronization therapy (CRT). The aim of this study is to evaluate in patients with left ventricular (LV) dyssynchrony whether response to CRT is related to myocardial viability in the region of the pacing lead. Methods: Forty-nine consecutive patients with advanced heart failure, LV ejection fraction < 35%, QRS duration > 120 ms and intraventricular asynchronism , 50 ms were included. Dobutamine stress echocardiography was performed within the week before CRT implantation. Resting echocardiography was performed 6 months after CRT implantation. Viability in the region of LV pacing lead was defined as the presence of viability in two contiguous segments. Response to CRT was defined by evidence of reverse LV remodeling (,15% reduction in LV end-systolic volume). Results: Thirty-one patients (63%) were identified as responders at follow-up. The average of viable segments was 5.9 ± 2 in responders and 3.2 ± 3 in nonresponders (P = 0.0003). Viability in the region of the pacing lead had a sensitivity of 94%, a specificity of 67%, a positive predictive value of 83%, and a negative predictive value of 86% for the prediction of response to CRT. Conclusions: In patients with LV dyssynchrony, reverse remodeling after CRT requires viability in the region of the pacing lead. This simple method using echocardiography dobutamine for the evaluation of local viability (i.e., viability in two contiguous segments) may be useful to the clinician in choosing the best LV lead positioning. (Echocardiography 2010;27:668-676) [source]

Ventricular Mechanical Asynchrony in Patients with Different Degrees of Systolic Dysfunction: Results from AVE Registry by the Italian Society of Cardiovascular Echography (SIEC)

ECHOCARDIOGRAPHY, Issue 2 2010
Scipione Carerj M.D.
Objective: The aim of the study was to compare the prevalence of interventricular and intraventricular asynchrony in patients with different degrees of left ventricular (LV) dysfunction. Methods: We enrolled 182 patients (male 79%, mean age 64 ± 11 years) with LV ejection fraction (EF) < 50% and identified two groups: Group A (n = 79) with mild-to-moderate LV dysfunction (EF between 36% and 49%) and Group B (n = 103) with severe dysfunction (EF , 35%). An echocardiogram was performed in all patients and a delay longer than 40 msec in the time difference between the aortic and pulmonary preejection intervals was considered as an index of interventricular asynchrony. The electromechanical delays were assessed by pulsed tissue Doppler technique. A time difference between the earliest and the latest segment greater than 40 msec was considered the cutoff for intraventricular asynchrony. The sum of asynchrony was calculated by adding to the LV intraventricular delay the delay between the lateral basal right ventricular segment and the most delayed LV basal segment. Results: The prevalence of interventricular asynchrony was lower among Group A patients (19.8% vs. 37.9%; P = 0.007) while the prevalence of intraventricular asynchrony did not differ between groups (32.9% vs. 44% in Group A and Group B respectively; P = 0.18). The sum of asynchrony (cutoff >102 msec) did not differ between groups either (29.9% vs. 35.9%; P = 0.39). Conclusions: The prevalence of intraventricular asynchrony is independent of the LV systolic dysfunction severity. This could indicate the potential role of cardiac resynchronization therapy in patients with mild-moderate systolic dysfunction. (ECHOCARDIOGRAPHY 2010;27:110-116) [source]

Usefulness and Limitation of Dobutamine Stress Echocardiography to Predict Acute Response to Cardiac Resynchronization Therapy

ECHOCARDIOGRAPHY, Issue 1 2010
F.R.C.P.C., Mario Sénéchal M.D.
Background: It has been hypothesized that a long-term response to cardiac resynchronization therapy (CRT) could correlate with myocardial viability in patients with left ventricular (LV) dysfunction. Contractile reserve and viability in the region of the pacing lead have not been investigated in regard to acute response after CRT. Methods: Fifty-one consecutive patients with advanced heart failure, LV ejection fraction , 35%, QRS duration > 120 ms, and intraventricular asynchronism , 50 ms were prospectively included. The week before CRT implantation, the presence of viability was evaluated using dobutamine stress echocardiography. Acute responders were defined as a ,15% increase in LV stroke volume. Results: The average of viable segments was 5.8 ± 1.9 in responders and 3.9 ± 3 in nonresponders (P = 0.03). Viability in the region of the pacing lead had an excellent sensitivity (96%), but a low specificity (56%) to predict acute response to CRT. Mitral regurgitation (MR) was reduced in 21 patients (84%) with acute response. The presence of MR was a poor predictor of response (sensibility 93% and specificity 17%). However, combining the presence of MR and viability in the region of the pacing lead yields a sensibility (89%) and a specificity (70%) to predict acute response to CRT. Conclusion: Myocardial viability is an important factor influencing acute hemodynamic response to CRT. In acute responders, significant MR reduction is frequent. The combined presence of MR and viability in the region of the pacing lead predicts acute response to CRT with the best accuracy. (Echocardiography 2010;27:50-57) [source]

Aortic Upper Wall Tissue Doppler Image Velocity: Relation to Aortic Elasticity and Left Ventricular Diastolic Function

ECHOCARDIOGRAPHY, Issue 9 2009
Soon Yong Suh M.D.
Background: Aortic stiffening contributes to the left ventricular (LV) afterload, hypertrophy, and substrate for diastolic dysfunction. It is also known that aortic elastic properties could be investigated with color tissue Doppler imaging (TDI) in aortic upper wall. The purpose of this study is to evaluate the relation of aortic upper wall TDI and aortic stiffness and other parameters of LV diastolic function. Methods: We examined aortic upper wall by TDI at the 3 cm above the aortic valves because of patient's chest discomfort or dyspnea. We excluded the patient with arterial hypertension or reduced left ventricular ejection fraction (LVEF) or significant valvular heart disease. So a total of 126 (mean age 53.8 ± 13.9 years, male 49.2%) patients were enrolled in this study and divided normal LV filling group (N = 31) and abnormal LV filling group (N = 95). Results: Aortic upper wall early systolic velocity and late diastolic velocity were not different between the two groups. Only aortic upper wall early diastolic velocity (AWEDV) was related to aortic stiffness index (r =,0.25, P = 0.008), distensibility (r = 0.28, P = 0.003), early diastolic (Em) (r = 0.45, P = 0.001), E/Em (r =,0.26, P = 0.003), and significantly reduced in abnormal LV filling group (6.19 ± 2.50 vs 8.18 ± 2.87, P = 0.001). Conclusions: AWEDV is decreased significantly in abnormal LV filling patients. It is statistically related to aortic stiffness, distensibility and parameters of abnormal LV filling, Em, E/Em. TDI velocity of the aortic upper wall can be a helpful tool for evaluating aortic stiffness, distensibility, and diastolic function. [source]

Mitral Regurgitation Associated with Mitral Annular Dilation in Patients with Lone Atrial Fibrillation: An Echocardiographic Study

ECHOCARDIOGRAPHY, Issue 8 2009
Takashi Kihara M.D.
Background: Whether and how lone atrial fibrillation (AF) is associated with functional mitral regurgitation (MR) remain unclear. Method: We studied 12 lone AF patients without left ventricular (LV) dysfunction and/or dilatation, who underwent mitral valve annuloplasty for functional mitral regurgitation (MR). Ten lone AF patients without MR served as controls. Results: Lone AF Patients with MR had a greater mitral valve annular area and left atrial area than those without MR. There were no differences in LV volumes or LV ejection fraction. Conclusions: Therefore, we concluded that left atrial dilation and corresponding mitral annular dilation may cause MR in lone AF patients without LV dysfunction and/or dilatation. [source]

Worsening of Left Ventricular End-Systolic Volume and Mitral Regurgitation without Increase in Left Ventricular Dyssynchrony on Acute Interruption of Cardiac Resynchronization Therapy

ECHOCARDIOGRAPHY, Issue 7 2009
Suman S. Kuppahally M.D.
Background: Responders to cardiac resynchronization therapy (CRT) have greater left ventricular (LV) dyssynchrony than nonresponders prior to CRT. Aim: We conducted this study to see whether the long term responders have more worsening of LV dyssynchrony and LV function on acute interruption of CRT. Materials and Methods: We identified 22 responders and 13 nonresponders who received CRT as per standard criteria for 23.73 ± 7.9 months (median 24.5 months). We assessed the acute change in LV function, mitral regurgitation (MR) and compared LV dyssynchrony in CRT on and off modes. Results: On turning off CRT, there was no significant worsening of LV dyssynchrony in both responders and nonresponders. The dyssynchrony measurements by SPWMD, TDI and 3D echocardiography did not correlate significantly. LVESV increased (p = 0.02) and MR (p = 0.01) worsened in CRT-off mode in responders only without significant change in LVEF or LV dimensions. Discussion and Conclusion: In long-term responders to CRT, there is alteration in the function of remodeled LV with acute interruption of CRT, without significant worsening of LV dyssynchrony. The role of different echocardiographic parameters in the assessment of LV dyssynchrony remains controversial. Even after long-term CRT reversely remodels the LV, the therapy needs to be continued uninterrupted for sustained benefits. [source]

Subtle Systolic Dysfunction May Be Associated with the Tendency to Develop Diastolic Heart Failure in Patients with Preserved Left Ventricular Ejection Fraction

ECHOCARDIOGRAPHY, Issue 4 2009
Hüseyin Sürücü M.D.
Background: We looked for an answer to the question of whether diastolic heart failure (DHF) is a reality or all heart failures are systolic. Method: 300 cases (hypertensive, aged, obese, etc.), not being diagnosed DHF, with preserved left ventricular (LV) ejection fraction (EF) but having the tendency to develop DHF in future were examined. One hundred and eighty cases without exclusion criteria were selected. Cases were assigned to three groups according to noninvasively obtained pulmonary capillary wedge pressure (PCWP). Results: In cases with higher PCWP (>10 mmHg), transmitral A velocity was increased (P < 0.001) and among the pulsed wave tissue Doppler imaging (pw-TDI) parameters Ea velocity was decreased (P < 0.001) and Ea-dt was prolonged (P < 0.005). In cases with lower PCWP (<8 mmHg), transmitral E velocity was higher (P< 0.001). Furthermore, a more meaningful relationship was found between PCWP and systolic pw-TDI parameters. In all the groups, it was observed that Sa velocity was progressively decreased and Q-Sa interval was progressively prolonged as PCWP increased (for all the groups P < 0.046). Conclusion: The question whether DHF is a reality or all heart failures are systolic may be answered as follows. Subtle systolic dysfunction may be associated with the tendency to develop DHF in patients with preserved LV ejection fraction. As in systolic heart failure (EF < 45%), in patients with preserved systolic function (EF , 45%), systolic and diastolic functions may impair together. The pw-TDI method may be more sensitive than standard echocardiography parameters in detection of systolic dysfunction in cases with preserved EF. [source]

Right Ventricular Adaptations Along with Left Ventricular Remodeling in Older Athletes

ECHOCARDIOGRAPHY, Issue 3 2009
Oner Ozdogan M.D.
Background: Afterload changes and anatomic interaction between the ventricles cause right ventricle (RV) adaptation along with left ventricle (LV) remodeling. This study was designed to evaluate RV adaptations along with LV remodeling and to determine the effect of aging on both ventricles in a population of older athletes. Methods: Echocardiographic characteristics of 48 endurance trained older athletes were examined by tissue Doppler imaging (TDI) and integrated backscatter (IBS). Results: Mean LV mass index was calculated as 107.8±17.0 g/m2. Twenty-two athletes were > 55 years old. Age was found to be a risk factor for diastolic dysfunction regarding lateral TDI velocities (Em < Am) (r = 0.385, P < 0.001). RV long-axis (LAX) diameters were associated with LA volumes and LV masses (r = 0.380, P < 0.01 and r = 0.307, P < 0.05). RV LAX diameters were correlated with RV TDI E-wave (r =,0.285, P < 0.05), RV LAX average, and peak IBS values (r = 0.36, P < 0.05 and r = 0.348, P < 0.05). Conclusions: TDI and IBS are applicable methods to evaluate the relationship between the two ventricles in athletes' heart. Increased RV LAX IBS values indicate increased LV mass and LA volume as a result of RV changes along with LV remodeling. Our data suggest that RV TDI E-wave and average RV IBS values reflect cardiac adaptations of both RV and LV in older athletes. [source]

Lack of Association between Obesity and Left Ventricular Systolic Dysfunction

ECHOCARDIOGRAPHY, Issue 2 2009
Mohammad Reza Movahed M.D., Ph.D.
Background: Previous studies have demonstrated that obesity is one of the risk factors for congestive heart failure (CHF). By analyzing a large database, we investigated any association between body mass index (BMI) and left ventricular (LV) systolic dysfunction. Methods: We retrospectively analyzed 24,265 echocardiograms performed between 1984 and 1998. Fractional shortening (FS) and BMI were available for 13,382 subjects in this cohort which were used for data analysis. FS was stratified into four groups: (1) FS > 25%, (2) FS 17.5,25%, (3) FS 10,17.5%, and (4) FS < 10%. Furthermore, we also used final diagnosis that was coded by the reading cardiologist as mild, moderate, and severe LV dysfunction separately for data analysis. BMI was divided into four groups: BMI < 18.5 kg/m2 (underweight), 18.5,24.9 kg/m2 (normal), 25,30 kg/m2 (overweight), and >30 kg/m2 (obese). Results: There was no association between different BMI categories and LV systolic function. The prevalence of mild, moderate, or severely decreased LV function (based on FS or subjective interpretation of reading cardiologists) was equally distributed between the groups. Obese patients (BMI > 30%) had normal FS of >25 in 16.9%, mildly decreased FS in 18%, moderately decreased FS in 18.4%, and severely decreased FS in 20.1% P = ns. Conclusion: Our study is consistent with previous trials suggesting that obesity is not related to systolic LV dysfunction. The underlying mechanism for the occurrence of congestive heart failure in obese patients needs further investigation. [source]

Evaluation of Subendocardial and Subepicardial Left Ventricular Functions Using Tissue Doppler Imaging after Complete Revascularization

ECHOCARDIOGRAPHY, Issue 2 2009
Hüseyin Sürücü M.D.
Objective: We aim to evaluate subepicardial and subendocardial left ventricular (LV) functions in patient single coronary artery lesion at early stage after percutaneous coronary intervention (PCI). Additionally, a comparison of LV functions between patients and control cases was aimed. Method: Patients with culprit left anterior descending (LAD) lesion (n = 25) and subjects with normal coronary angiography (n = 25) were evaluated. Patients underwent PCI and at least one coronary stent was placed. After PCI, the pulsed-wave tissue Doppler imaging (pw-TDI) parameters taken from subepicardial and subepicardial layers were compared among the patients. Results: Left atrium (P = 0.050), LV end-diastolic (P = 0.049), and end-systolic (P = 0.006) diameters were larger compared to the control group. LV inflow velocities were not different between the patient and the control group. But, the myocardial performance index was different (P = 0.049). The systolic and diastolic pw-TDI parameters were apparently different between the patient and the control group. While the systolic pw-TDI parameters did not change, the diastolic pw-TDI parameters taken from both subepicardial (circumferential contraction) and subendocardial layers (longitudinal contraction) improved after PCI. After PCI, it was shown that while Ea velocity (P = 0.012) taken from the subendocardial layer increased, IVRa velocity (P < 0.001) taken from the subepicardial layer decreased. Conclusion: In our study, it could be said that LV, left atrium, and aortic valve diameter increase in patients with coronary artery disease. The systolic and diastolic functions were impaired at subendocardial and subepicardial layers. These dysfunctions can be easily presented with pw-TDI. Although systolic dysfunction persists, diastolic dysfunction improves at early stage after PCI. [source]

Unusual Cause of Heart Failure in a 65-Year-Old Woman

ECHOCARDIOGRAPHY, Issue 10 2008
Mirela Tomescu M.D., Ph.D.
Left ventricular (LV) free wall rupture is a potentially lethal mechanical complication after myocardial infarction (MI). Pericardial adhesions or slow extracardiac leak and pericardial inflammation may result in a contained cardiac rupture. LV pseudoaneurysm is a relatively uncommon clinical entity. It may occur after MI, but also as a complication of infective endocarditis, cardiac surgery, or trauma. Patients developing LV pseudoaneurysm after MI may present angina pectoris or signs of congestive heart failure (HF) but often are asymptomatic. Surgery is the treatment of choice for LV pseudoaneurysms diagnosed in the first months after MI. The management of chronic LV pseudoaneurysms is still subject of debate. This report highlights a 65-year-old patient newly hospitalized for acute decompensated HF who was diagnosed with a large chronic LV pseudoaneurysm and severe mitral regurgitation. The patient underwent successful resection of the pseudoaneurysm and patch repair of the ruptured ventricular wall. [source]

Effect of Preload on Left Ventricular Longitudinal Strain by 2D Speckle Tracking

ECHOCARDIOGRAPHY, Issue 8 2008
Jin-Oh Choi M.D.
Background: Peak systolic longitudinal strain (PSLS) obtained using the 2D speckle tracking method is a novel indicator of the long-axis function of the left ventricle (LV). We used the 2D strain profile to examine the effect of preload reduction by hemodialysis (HD) on LV PSLS in patients with end-stage renal disease (ESRD). Method and results: Twenty-nine pairs of echocardiographic evaluations were obtained before and after dialysis. Global LV PSLS was ,18.4 ± 2.9%, at baseline and decreased to ,16.9 ± 3.2% after HD (P < 0.001). Segmental analysis showed that the decrease in PSLS after dialysis was most prominent in mid-LV segments (,17.1 ± 3.5% vs. ,15.4 ± 3.4%, P < 0.001). Conclusion: PSLS obtained from the 2D strain profile is a reliable parameter that may be useful for evaluating LV systolic long-axis function. However, PSLS should be applied cautiously in ESRD patients because it could be affected by dialysis. [source]

Is There Any Relationship between Metabolic Parameters and Left Ventricular Functions in Type 2 Diabetic Patients without Evident Heart Disease?

ECHOCARDIOGRAPHY, Issue 7 2008
Mehmet Yazici M.D.
Background: The aim of the present study was to evaluate left ventricle (LV) systolic and diastolic function, using tissue Doppler echocardiography (TDE) and color M-mode flow propagation velocity, in relation to blood glucose status in normotensive patients with type 2 diabetes mellitus (T2DM) who had no clinical evidence of heart disease. Methods: Seventy-two patients with T2DM (mean age 49.1 ± 9.8 years) without symptoms, signs or history of heart disease and hypertension, and 50 ages matched healthy controls (mean age 46.1 ± 9.8 years) had echocardiography. Systolic and diastolic LV functions were detected by using conventional echocardiography, TDE and mitral color M-mode flow propagation velocity (VE). Fasting blood glucose level (FBG) after 8 hours since eating a meal, postprandial blood glucose level (PPG), and HbA1C level were determined. The association of FBG, PPG and HbA1C with the echocardiographic parameters was investigated. Results: It was detected that although systolic functions of two groups were similar, diastolic functions were significantly impaired in diabetics. No relation of FBG and PPG with systolic and diastolic functions was determined. However, HbA1C was found to be related to diastolic parameters such as E/A, Em/Am, VE and E/VE (,=,0.314, P = < 0.05; ,=,0.230, P < 0.05; ,=,0.602, P < 0.001, ,= 0.387, P < 0.005, respectively). In addition to HbA1C, LV, diastolic functions were also correlated with age and diabetes duration. Conclusion: Diastolic LV dysfunction may develop even in absence of ischemia, hypertension, and LVH in T2DM. FBG and PPG have no effect on LV functions, but HbA1C levels may affect diastolic parameters. [source]

Effect of Alcohol-Induced Septal Ablation on Left Atrial Volume and Ejection Fraction Assessed by Real Time Three-Dimensional Transthoracic Echocardiography in Patients with Hypertrophic Cardiomyopathy

ECHOCARDIOGRAPHY, Issue 7 2008
Fadi G. Hage M.D.
Alcohol-induced septal ablation (AISA) is an accepted treatment for hypertrophic cardiomyopathy (HCM) patients with left ventricular (LV) outflow obstruction who are unresponsive to medical therapy. As left atrial (LA) enlargement has been correlated with increased morbidity and mortality in HCM, we assessed LA volumes and ejection fraction (EF) prior to and after AISA using real time three-dimensional (3D) transthoracic echocardiography (TTE) in 12 patients (9 women; mean age 52 ± 15 years; 11 Caucasian). All patients underwent successful AISA with no complications and their resting left ventricular outflow gradients decreased from 40.5 ± 22.2 to 9.1 ± 17.6 mmHg (P < 0.001) while their gradients with provocation decreased from 126.2 ± 31.7 to 21.8 ± 28.0 mmHg (P < 0.001). All patients showed improvements in their New York Heart Association (NYHA) functional class. Both the LA end-systolic (45.2 ± 12.9 to 37.2 ± 13.7 ml, P < 0.0001) and end-diastolic (79.6 ± 18.9 to 77.1 ± 18.6 ml, P = 0.001) volumes decreased after AISA. The LA EF increased from 43.1 ± 9.0 to 52.5 ± 8.8% (P = 0.001). The increase in LA EF correlated with the decrease in the resting left ventricular outflow gradient (R =,0.647, P = 0.03). In conclusion, 3D echocardiography can be utilized to follow LA function after AISA for HCM. AISA results in clinical improvement in patients with HCM and in improvement of LA EF that is correlated with the decrease in the left ventricular outflow gradient. [source]

Relationship between Left Ventricular Geometry and Left Ventricular Systolic and Diastolic Functions in Patients with Chronic Severe Aortic Regurgitation

ECHOCARDIOGRAPHY, Issue 6 2008
Murat Çayli M.D.
Background: Chronic aortic regurgitation (AR) is a form of volume overload inducing left ventricle (LV) dilatation. Myocardial fibrosis, apoptosis, progressive LV dilatation, and eventually LV dysfunction are seen with the progression of disease. The aim of the study was to assess the relation between LV geometry and LV systolic and diastolic functions in patients with chronic severe AR. Methods: The study population consisted of 88 patients with chronic severe AR and 42 healthy controls. The LV ejection fraction (LVEF) was calculated. Subjects were divided as Group I (controls, n = 42), Group II (LVEF > 50%, n = 47), and Group III (LVEF < 50%, n = 41). Transmitral early and late diastolic velocities and deceleration time were measured. The annular systolic (Sa) and diastolic (Ea and Aa) velocities were recorded. Diastolic function was classified as normal, impaired relaxation (IR), pseudonormalization (PN), and restrictive pattern (RP). Results: The LVEF was similar in Group I and II, while significantly lower in Group III. Sa velocity was progressively decreasing, but LV long- and short-axis diameters were increasing from Group I to Group III. Forty-six, 31 and 11 patients had IR, PN, and RP, respectively. LV long-axis systolic and diastolic diameters were significantly increasing, while LVEF and Sa velocity were significantly decreasing from patients with IR to patients with RP. The LV long-axis diastolic diameter is independently associated with LV systolic and diastolic functions. Conclusions: The LV long-axis diastolic diameter is closely related with LV systolic and diastolic functions in patients with chronic severe AR. [source]

Right Ventricular Dimensions and Function in Isolated Left Bundle Branch Block: Is There Evidence of Biventricular Involvement?

ECHOCARDIOGRAPHY, Issue 5 2008
Jeroen Van Dijk M.D.
Background: Isolated left bundle branch block (LBBB) may be an expression of idiopathic cardiomyopathy affecting both ventricles. The present study was conducted to evaluate right ventricular (RV) dimensions and function in asymptomatic LBBB patients with mildly depressed left ventricular (LV) function. Methods: Fifteen patients with asymptomatic LBBB in whom coronary artery disease, hypertension, and valvular pathology was excluded were studied. Fifteen healthy volunteers and 15 idiopathic dilated cardiomyopathy LBBB patients served as controls. RV long axis and tricuspid annulus diameter were obtained, as were tricuspid annular plane systolic excursion (TAPSE) and peak systolic velocity (Sm) of the RV free wall annulus. Tricuspid regurgitation (TR) jets (peak TR jets) were used for RV pressure assessment. Results: RV dimensions were comparable between the asymptomatic LBBB patients and controls. RV functions of healthy volunteers and asymptomatic LBBB patients were similar (TAPSE: 24 ± 3 and 24 ± 4 mm, Sm: 13 ± 2 and 13 ± 3 cm/s, respectively), whereas functional parameters in idiopathic dilated cardiomyopathy patients were significantly reduced (TAPSE: 19 ± 5 mm, Sm: 9 ± 2 cm/s, both P < 0.01 by analysis of variance [ANOVA]). For the three groups combined, a significant inverse correlation between RV pressure (peak TR jets) and RV function (Sm) was observed (r =,0.52, P = 0.017). Conclusions: In patients with an asymptomatic LBBB, RV dimensions and function are within normal range. The present study suggests that screening of RV functional parameters in asymptomatic LBBB patients is not useful for identification of an early-stage cardiomyopathy, and RV dysfunction is merely a consequence of increased RV loading conditions caused by left-sided heart failure and does not indicate a generalized cardiomyopathy affecting both ventricles. [source]